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Binkley, Laura ElysePrevalence of Cryptosporidium, Giardia, Salmonella, and Cephalosporin-Resistant E. coli Strains in Canada goose Feces Urban and Peri-Urban Sites in Central Ohio
Master of Science, The Ohio State University, 2015, Environment and Natural Resources
Large populations of resident geese can pose a pathogen exposure hazard and disease risk to humans and animals in urban areas. Evidence suggests that waterfowl play a role in pathogen dissemination and disease transmission to humans, however, more definitive data are often needed. This exploratory study sought to identify potential exposure hazards, the first step in risk assessment. This research also discusses dose-response for protozoan organisms and initiated the exposure assessment process by measuring environmental variables that may be associated with exposure. A total of 199 Canada goose fecal samples were collected from 5 peri-urban and 7 urban sites throughout the Greater Columbus, Ohio area. Samples were collected during two time periods: during 4-11 June, 2013 when geese had just begun their molt, and 16-30 August, 2013 after geese regained flight. Juveniles were distinguished from adults only during the first sample period. Antigen capture enzyme-linked immunosorbent assay (ELISA) was used to detect presence of Giardia and Cryptosporidium. Selective media were used to culture Salmonella and cephalosporin-resistant E. coli strains. Cryptosporidium was the most prevalent pathogen with 44.7% of samples testing positive. Feces collected from urban sites during the first period were 1.86 times more likely to be positive for Cryptosporidium than peri-urban sites (P = 0.10). Forward model selection methods determined that prevalence was positively associated with human population density surrounding collection sites, proportion of each site defined as pasture by the National Land Cover Database (NLCD), and distance of each site from nearest wastewater treatment plant (WWTP). Feces collected from urban sites during the second period were no more likely to be positive for Cryptosporidium than peri-urban sites (P = 1.00, Odds Ratio= 1.00). Forward stepwise model selection determined that prevalence was positively associated with human population density within study sites, distance of each site from nearest livestock farm, and distance of each site from nearest wastewater treatment plant. Giardia was present in only 3.5% of samples. None were positive for Giardia in the first period. Feces collected from urban sites during the second period were 1.9 times more likely to be positive for Giardia than peri-urban sites (P = 0.74). Prevalence of cephalosporin-resistant E. coli strains was 10.8%. Only one positive was detected during the first period. Feces collected from urban sites during the second period were 6.7 times more likely to be positive for cephalosporin-resistant E.coli than peri-urban sites (P = 0.10). No Salmonella was detected in the fecal samples. All pathogens tested, with the exception of Salmonella, showed a similar trend where a greater percentage of positives were detected at urban sites than peri-urban sites. The exposure potential of goose feces to the human population appears to be high for Cryptosporidium but low for Giardia and Salmonella. The discovery of cephalosporin-resistant strains of E.coli in fecal samples poses a potential exposure hazard because antibiotic-resistant strains are difficult to treat if infection occurs.

Committee:

Robert Gates, Dr. (Advisor); Michael Bisesi, Dr. (Committee Member); Stephen Matthews, Dr. (Committee Member)

Subjects:

Animal Diseases; Biology; Ecology; Environmental Studies; Epidemiology; Molecular Biology; Veterinary Services; Wildlife Management

Keywords:

zoonotic disease; canada goose; hazard identification; disease ecology

Yoak, Andrew JamesDisease Control through Fertility Control: Explorations in Two Urban Systems
Doctor of Philosophy, The Ohio State University, 2015, Evolution, Ecology and Organismal Biology
In many areas, wildlife populations have increased substantially in their local density because of a loss of natural controls or some artificially supplemented resource. These populations are often managed to avoid harmful effects on other wildlife species and human-wildlife conflicts. Many species are managed using lethal population reduction, but in those that are resistant to these means or where the method is unpalatable due to public concern, fertility control is becoming increasingly common. This method seeks to reduce the population size of some target problem species by capturing, sterilizing, and releasing individuals back into their habitat. Fertility control is often paired with vaccination programs because each has synergistic effects. Sterilization reduces the population size, making it easier to achieve a higher vaccination proportions for herd immunity. However, these programs have uncertain effects on both the basic biology, population demographics, and disease epidemiology. The current literature makes strongly countered species-specific conclusions. It is also unclear if fertility control is an effective method at reducing the population size in an economically viable way, compared to lethal removal. Here I use computer simulations, cross sectional surveys, and long-term monitoring of two populations, the street dogs (Canis lupus familiaris) of Rajasthan, India, and the raccoons (Procyon lotor) of the Columbus Zoo and Aquarium, to investigate what impact fertility control makes on the populations it targets. In Chapter 2, I exposed replicate simulated populations to various control schemes to see which most lowered the population size and increased vaccination coverage. In Chapter 3, I report the results of surveys of dogs from several real world Indian cities with varied histories of fertility control for several diseases. In Chapters 4 and 5, I report the results of a randomized control study on raccoons, which measured differences in parasite load and survival among control, vaccinated and vaccinated/sterilized individuals. My work demonstrates that fertility control programs can be more effective than lethal control, although the methods used to locate sexually intact individuals for treatment can significantly affect the results. In Chapter 3, I found that intact dogs living in cities with more fertility control had significantly lower prevalence of several diseases compared to those dogs living in cities with less fertility control. This is especially significant because the interventions only vaccinated against rabies, meaning that the fertility control affected local disease epidemiology. This indicates that the sterilization program buffered treated individuals’ ability to resist or spread disease enough to lower exposure to non-treated individuals. I found that sterilization and vaccination in raccoons did not affect the apparent monthly survival rates, but lowered parasite prevalence in males. However, female raccoon parasite prevalence was negatively affected by sterilization. I suggest that the sterilization method used does not eliminate hormone production, causing females to increase the length or intensity of their reproductive seasons. As a whole, this work highlights the importance of understanding the secondary effects of intervention policies. I show that altering reproductive behavior can cause dramatic changes to population dynamics and epidemiology.

Committee:

Ian Hamilton, Dr (Advisor); Stanley Gehrt, Dr. (Advisor); Rebecca Garabed, Dr. (Committee Member); Liza Comita, Dr. (Committee Member)

Subjects:

Animal Diseases; Ecology; Organismal Biology; Parasitology; Veterinary Services; Wildlife Management; Zoology

Keywords:

lethal control; fertility control; procyon lotor; raccoon; domestic dog; free roaming dog; street dog; canis lupus familiaris; agent based modeling; individual based modeling; dog population management;

LeShure, Shirron NicoleUse of Naturally Occurring Anthelmintics to Control Gastrointestinal Parasites in Small Ruminants
Doctor of Philosophy, The Ohio State University, 2014, Animal Sciences
There is a critical need to identify natural anthelmintics for food animal production because of the increased resistance of intestinal parasites to commercial anthelmintics and the inability to use commercial anthelmintics for certified organic food production. Condensed tannins (CT) and flavonoids have been investigated and shown varied efficacy as natural anthelmintics. This research was done to investigate the effects of utilizing by-products of the juice and wine making industries, pomegranate husk (PH) and grape pomace (GP), which both contain these bioactive compounds of interest. An extraction was done on both by-products to determine the concentration of CT available. Pomegranate husk varieties of interest, Parifanka and Desertnyi, contained approximately 1.49 and 2.02% CT on a dry matter (DM) basis, respectively. Grape pomace varieties, Shiraz and Cabernet Sauvignon, contained 4.83 and 3.68% CT, respectively. In vitro batch culture was conducted in a slope ratio design to determine the effects of the by-products on dry matter degradation (DMD) when compared to and mixed with a control, alfalfa hay. Both varieties of GP had lower (P <0.05) DMD at 96 h with greater than 70% dry matter remaining (DMR), however both varieties of PH had similar digestibilities as alfalfa with approximately 40% DMR. There was an inverse response in DMD when GP was mixed with the ground alfalfa hay; as the proportion of GP to alfalfa increased, the DMD decreased (P < 0.05). Parifanka PH had a DMD similar to alfalfa and did not have a significant effect (P > 0.10) on DMD in mixed ratios. Desertnyi PH was observed to have slightly better digestibility than alfalfa, and the DMD decreased with increasing alfalfa. In vitro parasitology studies were done on stage three larvae of O. ostetagia using extracts of PH and GP. There were several varieties of PH available, so preliminary studies were done to determine two varieties showing highest efficacy on larvae to use in subsequent studies. The Sogidana and Wonderful varieties were used for the PH, and Shiraz and Cabernet Sauvignon varieties were used for GP. Overall, both PH and GP extracts had approximately twice the number of inactive larvae present (P < 0.05) in the well at 24 h when compared to the control, 32 to 41% inactivity versus 17% inactivity, respectively. Grape pomace extracts had a marginally greater (P < 0.05) efficacy on reducing the viability of the parasites than the pomegranate husk extracts at 24 h when observed at 12.5 mg/mL of crude extract. The PH had a higher extractability than GP was able to reach 50 mg/mL of crude extract. The Wonderful variety of PH had the highest (P < 0.05) efficacy against the parasites when compared to Sogidana at the same concentration and against the control. Two trials were conducted for evaluating the effect of GP on mixed gastrointestinal helminth parasite infestation in growing lambs. The first trial examined the effect of a GP diet (28 g CT/kg DM) against a positive (Cydectin, no CT, normal alfalfa pellet diet) control and a negative control (no CT, normal alfalfa pellet diet). The second trial examined the effects of GP diets containing 25 (GPD1) or 45 (GPD2) g CT/kg DM against a negative control. Lambs were assessed for body weight (BW), FAMACHA© (anemia eye score), fecal egg count (FEC), average daily gains (ADG), packed cell volume (PCV) and feed intake (FI). In trial 1, there was an increase (P < 0.05) in BW observed each week which would be expected as the lambs grew, irrespective of treatment. As the weeks progressed, the treatments varied in ADG with the Cydectin treatment group having the highest (P < 0.05) ADG by week 3. FI and FAMACHA© were not different (P > 0.10) between treatments but FI increased (P < 0.05) weekly. There was no difference (P > 0.10) observed between treatments for PCV until the second week in which the Cydectin treatment had the highest (P < 0.05) PCV at 33.2±1.8% and continued to have the highest (P < 0.05) PCV for the duration of the trial. Cydectin treated lambs also had the lowest (P < 0.05) FEC with there being no differences (P > 0.10) between the negative control and GP treatment groups. I expected to observe a decrease in FEC with the positive control and GP diet compared to the negative control, but this result was not observed. Body weight also increased (P < 0.05) with time in trial 2. ADG was higher (P < 0.05) for GPD1 during the first week when compared to the control and other GP diet. After the first week, the negative control had the highest (P < 0.05) ADG but by week 3 there was no difference (P > 0.10) observed between treatments. PCV also increased (P < 0.05) over time with there being no differences (P > 0.10) between treatments. There were no differences (P > 0.10) observed between treatments for FEC. FAMACHA© scores and FI increased (P < 0.05) over time but there were no differences (P > 0.10) between treatments. An egg hatch and larval development study was done on feces from parasitized lambs from different farming practices (organic versus conventional) in the presence or absence of GP extract (38 g CT/kg DM) to evaluate the effects of GP on egg hatchability and larval development. The GP treatment showed a 100% inhibition (P < 0.05) of egg hatch into developing larvae when compared to the control distilled water treatment. The data from the research conducted has shown that GP from the wine industry and PH have efficacy against larval helminth stages of GIP and GP also has efficacy against egg hatchability and larval development. The PH and GP could potentially have practical application in becoming a natural anthelmintic for small ruminants, but more in depth studies are needed to verify and finalize application methods.

Committee:

Maurice Eastridge (Advisor); Steve Loerch (Committee Member); Normand St-Pierre (Committee Member); Jeffrey Firkins (Committee Member); Sandra Solaiman (Committee Member)

Subjects:

Animal Diseases; Animal Sciences

Keywords:

gastrointestinal parasites; grape pomace; sheep; pomegranate husk; condensed tannins; natural anthelmintics

Hamberg, Alexander DavidStudies of circular single stranded DNA viruses of swine
Doctor of Philosophy, The Ohio State University, 2009, Veterinary Biosciences
Porcine circovirus 2 (PCV2) and porcine torque teno virus (TTV) are single stranded DNA (ssDNA) viruses that have the ability to cause disease in conjunction with other pathogens or sources of immunomodulation and are emerging pathogens of swine. PCV2 is the necessary infectious cause for the production of post-weaning multisystemic wasting syndrome (PMWS), and the sudden global emergence of epidemic PMWS remains unexplained. Immunohistochemical and in vitro culture-based methodologies have suggested that macrophages are likely sites of viral replication; however the tissues and cells involved in PCV2 replication have not been fully delineated. Current immunohistochemical (IHC) methodologies identify PCV2 antigens but are not capable of differentiating replicating virus from non-replicating virion particles in vivo. In Chapter 1, a combination of IHC with commercial monoclonal antibodies specific for single stranded (ss) and double stranded (ds) DNA and PCV2 specific in situ hybridization (ISH) was used to show the specificity of the former for PCV2 DNA in tissue sections from PCV2-infected gnotobiotic pigs. Cold-ethanol-fixed tissue sections were superior to formalin-fixed tissues for detection of PCV2 DNAs, presumably due to the lack of protein cross-linking in the former. These data demonstrate that conventional IHC detects PCV2 DNA forms in mononuclear cells of experimentally infected, PCV2-positive gnotobiotic porcine tissue sections that are minimally compromised by either formalin fixation or the harsh conditions needed for ISH. In chapter 2, we investigated a PCV2 reference pathogenic isolate engineered to contain a unique genotype identified in archival porcine clinical samples collected 26 years prior to the first reports of epidemic PMWS. This three amino acid threonine-glycine-asparagine to alanine-threonine-alanine (Thr-Gly-Asn to Ala-Thr-Ala) sequence in the C-terminus region of the nucleocapsid protein distinguishes archival PCV2 from contemporary PCV2. Groups of gnotobiotic piglets inoculated with each virus demonstrated that this region of the PCV2 genome was critical for the spread of PCV2 beyond lymphoid tissues and suggest that genetic mutations in avirulent PCV2 may account for the emergence of virulent PCV2 and PCVDs including epidemic PMWS. The pathogenic ability of TTV has recently been demonstrated in gnotobiotic swine and is supported by experimental and epidemiologic data from conventional swine. In chapter 3 we used quantitative PCR to examine the course of TTV progression through tissues in vivo and assessed viral copy numbers of both PCV2 and genogroup 1 TTV (g1-TTV) DNAs with respect to clinical disease outcomes and co-infection with both viruses. While bone marrow was an important source of TTV DNA during early infection, spleen, liver and lung contained the highest levels of TTV during the late infection time periods. Currently little is known about the intra-cellular effects of TTV infection. In chapter 4 we examined a variety of g1-TTV-infected tissues from gnotobiotic piglets to explain the ultrastructural basis for histological lesions characteristic of g1-TTV. Transmission electron micrographs of porcine tissues infected with g1-TTV identified 35nm diameter electron-dense structures in serum and the cytoplasm of mononuclear cells in the bone marrow, lung and inguinal lymph nodes. The viral inclusion bodies observed by light microscopy did not contain virus-like particles.

Committee:

George Krakowka, PhD DVM (Advisor); Charles Brooks, PhD (Committee Member); John Ellis, PhD DVM (Committee Member); Michael Lairmore, PhD DVM (Committee Member); Michael Oglesbee, PhD DVM (Committee Member)

Subjects:

Animal Diseases; Livestock; Microbiology; Molecular Biology; Pathology; Virology

Keywords:

Porcine circovirus type 2; PCV2; porcine torque teno virus; TTV; qPCR; electron microscopy

Ladrick, AliceIsotope
Master of Arts, Miami University, 2012, English
By referencing elements of the domestic and positioning the female body within that space, this thesis attempts to create non-traditional, partially autobiographical narratives that delve into gendered representations of selfhood as well as women’s relationships with the world around them (including relationships to men, other women, etc.). The epistolary form of Dear Alice emphasizes the role of address in narration and the representation of the self through written text. This form draws attention to the relationship between author and speaker, speaker and reader, and author and reader, as well as to the artifice of intimacy that direct address can create. Meanwhile, Isotope and The love of my life is emotionally inept use pop culture references, punning, and inventive line breaks to address similar questions of intimacy and representations of female desire and sexuality.

Committee:

Catherine Wagner (Committee Chair); cris cheek (Committee Member); Keith Tuma (Committee Member)

Subjects:

Aging; Animal Diseases; Canon Law; Dance; Dental Care; Fish Production; Gynecology; Wood

Keywords:

poetry; feminist; women; pop culture; Fugazi; Jonathan Lohr; cat butt

Walker, Jennifer B.Towards a Better Understanding of the Epidemiology of Naturally Occurring Staphylococcus aureus Intramammary Infections
Doctor of Philosophy, The Ohio State University, 2010, Veterinary Preventive Medicine

Staphylococcus aureus (SA) is the most prevalent contagious mastitis pathogen on US dairies and contributes significantly to cow mortality and loss of revenue. Despite its prevalence, our understanding of the epidemiology of naturally occurring SA intramammary infections (IMI) is limited. The research described herein attempts to provide a basic understanding of the epidemiology of naturally occurring SA IMI.

Using samples collected during two studies, we found that the sensitivity of microbiologic culture for detecting SA IMI using a 0.01mL inoculum was 91% and the specificity was 99.4%. Using a larger (0.1mL) inoculum the sensitivity increased to 96.8% and the specificity was 99.3%. This study demonstrated a clear benefit of using a larger inoculum volume (0.1mL) for culture in the microbiologic detection of SA IMI.

The daily shedding patterns of SA over three 21 day sample periods was evaluated. Although the amount of SA recovered from infected quarters varied tremendously, 97.7% of the samples were culture positive. There were no consistent patterns of shedding or a relationship between shedding of SA and SCC. Using pulse field gel electrophoresis (PFGE) to evaluate the association of strain type and shedding of SA, quarters grouped into PFGE pulsotype 1 shed at consistently higher levels and with comparatively little variability, (median cfu/0.01mL=100) while quarters placed in PFGE pulsotype 2 shed SA at consistently lower levels (median cfu/0.01mL=59, p< 0.0001).

The second study examined naturally occurring SA IMI on 2 different dairies over an entire lactation further demonstrating a consistent recovery of SA from naturally infected quarters provided a large enough (0.1mL) inoculm was used. The sensitivity of culture was 95%, compared to 85% when using a smaller volume (0.01mL). There were no consistent shedding patterns, other than that of consistently higher versus consistently lower. Quarters shedding consistently higher levels of SA were again grouped into PFGE pulsotype 1 further supporting the influence of strain type on either persistence or pathogenicity. Strains clustered into PFGE pulsotype 1 had a median cfu/0.01mL of 83 while strains grouped into PFGE pulsotype 2 had a median cfu/0.01mL of 17.

The third study examined the effect of strain type on SA IMI cure rates. Evaluating cure by parity, 42% of the first lactation cows cured while only 10% of the multiparous cows cured. We found no significant difference (p=0.64) in cure rates in quarters with low quarter level SCC (200,000 cells/mL) and high SCC. Nor was there any significant difference (p = 0.35) when evaluating cure using composite test day information.

In conclusion, when using a larger inoculum volume, the influence of bacterial shedding on the microbiological diagnosis of SA IMI is minimal. While there were no shedding pattern or cycle identified in shedding, quarters infected with bacteria in pulsotype 1 shed at significantly higher levels and experience fewer cures over the dry period. This highlights the potential for pre-screening heifers prior to parturition for SA IMI and possible dry cow therapy providing a cure for SA IMI before the heifer enters the milking parlor.

Committee:

Fred DeGraves, PhD (Advisor); Paivi Rajala-Schultz, PhD (Committee Member); Thomas Wittum, PhD (Committee Member); Wondwossen Gebreyes, PhD (Committee Member)

Subjects:

Animal Diseases

Keywords:

Staphylococcus aureus; Intramamamry Infection

Korfel, Chelsea AnneDistribution and environmental correlates between amphibians and the fungal pathogen, Batrachochytrium dendrobatidis
Doctor of Philosophy, The Ohio State University, 2012, Evolution, Ecology and Organismal Biology
Amphibian populations worldwide are vulnerable to a variety of threats, and one serious cause of population declines and extinctions is the amphibian pathogenic fungus Batrachochytrium dendrobatidis (Bd). Amphibian species of tropical, montane regions have suffered the greatest impacts of Bd- related declines, extirpations, and extinctions. Bd is also present in temperate regions, but the effects of Bd on temperate amphibian species appear to be less severe although remain poorly understood. Bd impacts populations, species, and individuals differentially and environmental factors affect host – pathogen relationships. Temperature varies along seasonal, altitudinal, and landscape gradients and is much more variable in temperate ecosystems than in tropical montane ecosystems. I examine the relationship between amphibian hosts and the pathogen Bd in the framework of temperature along these gradients and in these ecosystems. I reviewed the literature and identified a need to support Bd temperature regimes identified by laboratory studies with research conducted among wild populations. In a temperate ecosystem, I found high rates of Bd with widespread geographic (19.5% Bd positive) and amphibian taxonomic distribution (68% of species infected) in Ohio, USA. When patterns were examined more closely among green frogs (Lithobates clamitans) and bullfrogs (L. catesbeianus), I found high rates of Bd prevalence were associated with cooler temperatures such as those experienced in springtime (89% prevalence) and stream habitats (54%). In contrast, I found high infection intensities among amphibians were associated with warmer temperatures such as those experienced in summer (8,240 ± 31,852 ZE) and emergent streams (72,645 ± 18,092 ZE). In a tropical montane ecosystem, I found that Bd is geographically widespread but persists at low prevalence (7%) among Gastrotheca pseustes tadpoles collected from mid to high elevation sites in the Ecuadorian Andes. Infected tadpoles were of poor body condition compared to their uninfected conspecifics. Bd persists in high montane environments despite cool temperatures and negatively impacts tadpole growth, but may be less virulent at mid to high elevation sites compared to low altitudes. This may provide rationale for the persistence of an endemic harlequin frog, Atelopus exiguus, that persists at 3100 masl while many harlequin frog species distributed at lower elevations have recently gone extinct. Together, these chapters provide perspective on the relationship between amphibians and the fungal pathogen, Bd and recommendations to inform future efforts in global amphibian conservation.

Committee:

Thomas Hetherington (Advisor); Thomas Mitchell (Committee Member); Stanley Gehrt (Committee Member); David Stetson (Committee Member)

Subjects:

Animal Diseases; Biology; Conservation; Ecology; Organismal Biology; Wildlife Conservation

Keywords:

amphibian disease; Bd; conservation; temperature gradient

Morrow, Luke AdamFactors limiting the dietary inclusion level of dried distillers grains with solubles in ruminant diets
Master of Science, The Ohio State University, 2012, Animal Sciences

Dried distillers grains with solubles (DDGS) are a byproduct of the ethanol industry that may be cheaper than corn and nearly equal to corn in energy content. However, including DDGS in ruminant diets can reduce feed intake, average daily gain (ADG), and negatively impact animal health due to sulfuric acid that is added during ethanol production. Sulfuric acid lowers rumen pH and contributes to dietary sulfur (S). Low rumen pH is associated with reduced dry matter intake (DMI), ADG, and protein, and fiber digestibility. Increases in dietary S are associated with reduced DMI, ADG, and increased incidence of polioencephalomalacia (PEM). A series of experiments was conducted in cattle and lambs to discover management strategies that would allow for the increased use of DDGS in ruminant diets by alleviating the negative impacts that dietary acid and S have on ruminant species.

Chapter 3 describes two experiments conducted with cattle to determine effects of two levels of hay in corn and DDGS-based diets on feedlot performance, rumen pH, rumen short chain fatty acids, rumen S metabolism, and in situ dry matter disappearance of soy hulls. Cattle fed DDGS had 5.7% reduced DMI, 2.7% decreased final BW (P < 0.05), and tended to have decreased (P = 0.09) ADG compared to those fed corn. Increasing supplemental hay from 7 to 14% of the diet did not improve performance or lower ruminal hydrogen sulfide gas (H2S) concentration of cattle fed corn or DDGS-based diets. However, supplemental hay tended to improve rumen pH and measures of fiber digestion.

Chapter 4 describes two experiments that were conducted with lambs to determine effects of DDGS treated or untreated with 2% NaOH and two levels of dietary S on feedlot performance, ruminal H2S concentration, and apparent nutrient digestibilities. Lambs fed NaOH treated DDGS had 4% greater (P =0.05) final BW and tended (P < 0.07) to have greater DMI and ADG than lambs fed untreated DDGS; however, NaOH treatment did not affect (P > 0.42) G:F. Increasing dietary S by 0.2% with Na2SO4 tended (P < 0.08) to reduce DMI compared to lambs fed diets not supplemented with S; however, dietary S did not affect (P > 0.17) ADG, G:F, or final BW. Rumen gas samples collected on d 32 and 60 were not (P > 0.17) affected by dietary S or DDGS treatment. Treating DDGS with NaOH reduced (P = 0.05) NDF digestibility by 10% compared to lambs fed untreated DDGS. Urine pH for lambs consuming treated DDGS was increased (P = 0.01) 1.74 pH units compared with urine from lambs fed untreated DDGS. Nitrogen intake and retention was not affected (P > 0.35) by dietary S concentration or NaOH treatment of DDGS.

Committee:

Steven Loerch, PhD (Advisor); Francis Fluharty, PhD (Advisor); Kristy Daniels, PhD (Committee Member)

Subjects:

Agriculture; Animal Diseases; Animal Sciences

Keywords:

DDGS; sulfur; polioencephalomalacia; acidosis; cattle; lambs; rumen pH;

Tabacca, Natalie EllenEpithelial Migration on the Canine Tympanic Membrane
Master of Science, The Ohio State University, 2011, Veterinary Clinical Sciences
The tympanic membrane and external auditory canal serve auditory and non-auditory functions. Both the luminal surface of the external auditory canal and the lateral surface of the tympanic membrane are composed of a stratified squamous, keratinizing epithelium. Epithelial migration is a process that serves as a self-cleaning and repair mechanism for the external auditory canal and tympanic membrane. Epithelial migration has been evaluated in humans and several other species, but not in dogs. The majority of these studies employ an ink drop method in which discrete markers of ink are placed on the lateral surface of the tympanic membrane and the pattern and rate of these markers are monitored over time. Failure or abnormal epithelial migration has been implicated as a potential cause of some otic diseases in humans and has been assessed in otitis externa, keratosis obturans, external auditory canal cholesteatomas, retraction pockets, and middle ear cholesteatomas. The objectives of this study were to determine the rate and pattern of epithelial migration on the tympanic in clinically normal laboratory dogs and to describe a technique for ink drop placement on the canine tympanic membrane to be used for future studies. Eighteen dogs were anesthetized, and three drops of waterproof drawing ink were placed on two sites of the pars tensa and one on the pars flaccida. Images were recorded with a video otoscope and digital capture system. Each dog was evaluated and images recorded every six to eight days for four evaluations. Migration pattern analysis and epithelial migration rate calculation were performed with image processing software. Descriptive statistics for epithelial migration rate (mean, standard deviation, 95% confidence interval) were calculated for all ink drop locations on the tympanic membrane (pars tensa 1 [PT1], pars tensa 2 [PT2], and pars flaccida [PF]) at each time point. Eight fox hounds had digital images from both ears that met the criteria for image analysis, while all beagles and two fox hounds only had images from one ear that met the criteria for image analysis. No significant differences in the mean epithelial migration rates were identified between right and left ears of the eight fox hound dogs, between breeds (beagle, fox hound), or between locations PT1 and PT2. The mean overall epithelial migration rates (±standard deviation) were 96.4 (±43.1) and 225.4 (±128.1) micrometers per day for the pars tensa and pars flaccida, respectively. All ink drops moved outwards, the majority (48 of 53) in a radial direction, from the original location to the periphery of the tympanic membrane. Migration of the ink drops off the tympanic membrane was observed during the study period for all three locations. The ink drop placement method used in this study can be used in future studies to determine the epithelial migration rate of the canine tympanic membrane. Future investigations of epithelial migration should focus on dogs of different ages, dogs predisposed to otic diseases, as well as dogs with existing otic conditions.

Committee:

Lynette Cole, DVM, MS (Advisor); Andrew Hillier, DVM, MS (Committee Member); Paivi Rajala-Schultz, DVM, PhD (Committee Member)

Subjects:

Anatomy and Physiology; Animal Diseases; Audiology

Keywords:

tympanic membrane; canine; epithelial migration; otology; veterinary medicine; ear drum; dog

Karnik, KetakiAccuracy of Computed Tomography in Determining Lesion Size in Canine Osteosarcoma of the Appendicular Skeleton
Master of Science, The Ohio State University, 2011, Comparative and Veterinary Medicine
Multidetector contrast enhanced computed tomography with acquisition of 0.625 mm thick axial transverse images was used to measure the extent of appendicular osteosarcoma (OSA) in 10 dogs. The measured length of tumor based on CT was compared to the true length of tumor using histopathology. There was good correlation of the true length of OSA compared to the length of intramedullary/endosteal abnormalities on CT with a mean overestimation of 1.8% (SD = 15%). There was poor correlation of the true length of OSA compared to the length of periosteal proliferation on CT with a mean overestimation of 9.7% (SD = 30.3%). There was poor correlation of the true length of OSA compared to the length of abnormal contrast enhancement by 9.6% (SD = 34.8%). The measured extent of intramedullary/endosteal abnormalities using sub-millimeter thick axial transverse acquisition of images with multidetector CT should be of value in assessing patient candidacy and surgical margins for limb spare surgery. It may also be useful for evaluating response to therapy in dogs that receive chemotherapy or radiation therapy when surgery is not performed.

Committee:

E Green, DVM (Advisor); Steven Weisbrode, DVM (Committee Member); Cheryl London, DVM (Committee Member)

Subjects:

Animal Diseases; Animal Sciences; Animals; Medical Imaging; Medicine; Veterinary Services

Keywords:

CT; computed tomography; OSA; osteosarcoma; multidetector; appendicular; canine; dog; neoplasia; bone

Ghanem, Mostafa Ghanem AhmedDevelopment of Advanced Molecular Tools for Sequence Typing and Epidemiological Investigation of Avian Mycoplasma in Poultry
Doctor of Philosophy, The Ohio State University, 2017, Comparative and Veterinary Medicine
There are four avian mycoplasma species (spp.) that are pathogenic to poultry; Mycoplasma gallisepticum (MG), Mycoplasma synoviae (MS), Mycoplasma iowae (MI), and Mycoplasma meleagridis (MM). Avian mycoplasma caused infections represent significant economic burden on commercial poultry industry in the form of decreased egg and meat production efficiency, decreased market value of breeder flocks, carcass condemnation, and medication costs. Avian mycoplasma strain differentiation is a cornerstone for outbreak investigation, understanding infection dynamics, and epidemiology as well as planning future prevention and control strategies. Currently, avian mycoplasma strain differentiation is based on two main approaches; DNA fingerprinting and single or multiple locus based sequence typing. Despite that sequence typing approaches have many advantages over DNA fingerprinting approaches, they have many limitations. Recently due to the advanced next generation sequencing technologies, microbial whole genome sequencing (WGS) has become more feasible and resulted in a paradigm shift in the efficiency of outbreak investigation, understanding infection dynamics and epidemiology as well as planning future prevention and control strategies for many human and animal pathogens. The efficiency of WGS based strain differentiation approaches have superseded that of single or multiple loci based sequence typing approaches. The aim of this work was to improve and upgrade the currently used molecular typing tools for avian mycoplasma strain differentiation and in turn, epidemiological outbreak investigation via the development and application of state-of-the-art molecular typing approaches. This should be reflected in better prevention and control strategies and ultimately increasing the chances of successful eradication of avian mycoplasma spp. from commercial poultry. This dissertation is organized into an introduction and five chapters; the first chapter of this dissertation presents a review of literature about the history and development of microbial typing approaches since the discovery of bacteria with a focus on sequencing-based molecular typing approaches and the current state-of-the-art, whole genome sequence based typing approaches. This review should convey to the readers a basic understanding of advantages and disadvantages of main bacterial typing approaches and the context of these different typing approaches that are used in veterinary clinical microbiology. The second chapter describes the development and evaluation of a multilocus sequence typing assay (MLST) for Mycoplasma iowae. This assay is based on the amplification sequencing, and sequence analysis of six gene segments (total of 5019bp) (dppC, ulaA, valS, rpoC, leuS, kdpA) from tested samples. It allowed the differentiation of 47 MI samples into 23 unique sequence types. MLST generated phylogenetic trees and clonal groups displayed a high degree of agreement with geographical and temporal information of the tested samples. This assay allowed sequence typing of MI directly from clinical samples and minimized the need for MI isolation that was indispensable for MI strain differentiation using the DNA fingerprinting technique, Random Amplified Polymorphic DNA (RAPD). Online databases for MI sequence typing and archiving of isolates epidemiological information were launched on the PubMLST website. This assay and the database could be used to better understand the global epidemiology of MI population as well as facilitating the application of better control and eradication strategies. The third chapter describes the development and evaluation of whole genome sequence (WGS) based typing approach, Core Genome Multilocus Sequence Typing (cgMLST) scheme for Mycoplasma gallisepticum (MG), the most pathogenic avian mycoplasma spp. This scheme uses the same concept of conventional MLST however, instead of using the sequence information of 6 to 7 genes; it uses the sequence information of 425 different genes to differentiate between the WGS of MG isolates. A diverse collection of 81 MG samples from five countries in four continents were typed using this scheme. Forty five out of the 81 MG whole genome sequences were generated in this study alone. This scheme successfully differentiated between closely related samples of the same outbreak with a high degree of resolution, reliability, and reproducibility which could not be resolved by conventional multilocus based sequence typing schemes. M. gallisepticum cgMLST could serve as a standard method for MG strain differentiation. To the best of our knowledge, M. gallisepticum CgMLST is the first whole genome based typing scheme to be used for typing and epidemiological investigation of a strict poultry and livestock pathogen like MG. This project was disclosed as an invention with reference number IDF-036332 at The Ohio State University technology and commercialization office. The fourth chapter is also describing the development of a Core Genome Multilocus Sequence Typing (cgMLST) scheme for Mycoplasma synoviae. High prevalence and pathogenicity of MS infections have been reported in recent years, intensifying the need for more efficient molecular typing tools for outbreak investigation than the currently used schemes. A cgMLST was developed based on 302 core genes and used to type a diverse set of 44 MS isolate’s whole genomes from six countries in 4 continents. A total of Forty out of the 44 whole genome sequences were generated in this study. cgMLST typing of these isolates allowed differentiation between samples of the same MLST type. Moreover, cgMLST allowed evaluation of two currently available conventional MLST schemes. cgMLST provided stable and expandable nomenclature, allowing for comparing and sharing the typing results between different laboratories worldwide. In addition, it represents an example to harness the tremendous power of next generation sequencing technology in applied avian mycoplasma epidemiology at local and global levels. This project was disclosed as an invention with reference number IDF-036339 at The Ohio State University technology and commercialization office. The fifth chapter is a statement of research work done in this dissertation and future directions of that research.

Committee:

Mohamed El-Gazzar (Advisor)

Subjects:

Animal Diseases; Epidemiology; Microbiology; Veterinary Services

Keywords:

avian mycoplasma, Mycoplasma gallisepticum, Mycoplasma synoviae, mycoplasma Iowae, Whole genome sequencing, Multiple locus sequence typing;MLST, Core genome multilocus sequence typing cgMLST

Kathayat, DipakIdentification of Novel Small Molecule Growth Inhibitors Specific to Avian Pathogenic Escherichia coli
Master of Science, The Ohio State University, 2017, Comparative and Veterinary Medicine
Avian Pathogenic E. coli (APEC), an extraintestinal pathogenic E. coli (ExPEC), is one of the most common bacterial pathogens affecting chickens, turkeys, and other avian species. It causes multiple extra-intestinal infections which subsequently lead to high morbidity and mortality, production losses, and increased slaughter condemnation resulting severe economic loss to the global poultry industry. Antimicrobial medication is the major approach currently employed to reduce the incidence and mortality associated with this infection. However, multi-drug resistant (MDR) APEC strains are reported nowadays worldwide. Furthermore, vaccination which is used as a subsidiary approach to prevent infection frequency is not sufficient to provide protection against diverse heterologous APEC serotypes. Therefore, the objective of this study is to identify novel small molecule (SM) growth inhibitors of APEC and to evaluate toxicity and efficacy of identified SMs, in vitro and in vivo. Here, using a Tecan Sunrise™ absorbance plate reader, a pre-selected enriched SM library containing 4,182 SMs was screened at 100 µM concentration against a predominant field APEC serotype, APEC O78, grown in minimal M63 media. Of the total 4,182 SMs, 41 SMs inhibited APEC O78 growth. The majority of growth inhibitory SMs were found belonging to chemical groups; quinolines, piperidines, pyrrolidinyls, and imidazoles. Among 41 SMs, 30 SMs exhibited bacteriostatic activity, while remaining 11 SMs displayed bactericidal activity and were selected for further studies. Dose-response analysis of these selected SMs revealed their dose-dependent activity with minimal inhibitory concentration (MIC) ranging 12.5 µM to 200 µM. These selected SMs were found broadly effective against various APEC serotypes such as O1, O2, O8, O15, O18, O35, O109, and O115. Six of these SMs exhibited narrow-spectral activity affecting 1-3 tested commensal bacteria. Except SM11, other SMs were least toxic to Caco-2 epithelial (<10%) and HD11 macrophage cells (<10%) at 200 µM concentration. Seven of these SMs were least hemolytic (<10%) to avian and sheep red blood cells, whereas remaining four SMs were more hemolytic (>20%) at 200 µM concentration. All of the selected SMs were found effective in significant (P<0.01) reduction of intracellular APEC O78, O1, and O2 survival in infected Caco-2, HD11 and THP-1 cells at varying concentrations ranging from 1X to 2X of MIC. No resistance was observed to any of these selected SMs when APEC O78 was treated at lethal (2X MBC) or sub-lethal (0.75X MIC) concentration of SMs. In vivo evaluation of these SMs using greater wax moth (Galleria mellonella) revealed their low toxicities (<10%), except for SM1. Furthermore, treatment with these SMs significantly (P<0.0001) extended the survival of infected larvae, except for SM8, and significantly (P<0.05) reduced the APEC load inside the larva, except for SM8 and SM9. In summary, we have identified 11 novel anti-APEC SMs. Our future studies will focus on investigating; effects of these SMs on APEC preformed biofilms, interactions with antimicrobials that are currently being used, effects in infected chickens, and elucidation of their mechanism of actions. We expect that these studies will enable the development of novel narrow-spectrum SM antimicrobials for the control of APEC infections.

Committee:

Gireesh Rajashekara (Advisor); Chang-Won Lee (Committee Member); Anastasia Vlasova (Committee Member)

Subjects:

Animal Diseases; Microbiology; Therapy; Veterinary Services

Keywords:

Small molecules, novel antimicrobials, avian pathogenic Escherichia coli, antimicrobials resistance

Finney, Sarah KathrynEpidemiology of Non-typhoidal Salmonella in Veal Calves
Master of Science, The Ohio State University, 2017, Comparative and Veterinary Medicine
Non-typhoidal Salmonella in lymphatic tissues of animals at slaughter is believed to be a source of foodborne Salmonella infections. Prevalence of Salmonella has not been determined in veal calves. This longitudinal observational study used a vertically integrated veal production system to determine the prevalence of Salmonella on-farm and at slaughter. Producer treatment records were analyzed in order to understand the burden of disease and frequency of antimicrobial use associated with the recovery of Salmonella. Fecal samples, health records, and environmental and water samples were collected from 9 cohorts of calves. Calves from four cohorts were followed to slaughter, where mesenteric and pre-femoral lymph nodes and fecal samples were collected. Salmonella prevalence was 1.07% (4/374), 3.75% (6/160), 20.9% (33/158), and 0.68% (1/148) for on-farm fecal, slaughter fecal, mesenteric lymph nodes, and pre-femoral lymph nodes, respectively. There was no significant association between the presence of Salmonella in farm fecal samples, slaughter fecal samples, and mesenteric lymph nodes. Calves with positive mesenteric lymph nodes tended to be more likely to have positive pre-femoral lymph nodes (p=0.07).

Committee:

Gregory Habing, Dr. (Advisor); Thomas Wittum, Dr. (Committee Member); Margaret Masterson, Dr. (Committee Member)

Subjects:

Animal Diseases

Keywords:

Salmonella, veal calves

Elshafae, Said Mohammed AbbasPathogenesis and Treatment of Canine Prostate Cancer
Doctor of Philosophy, The Ohio State University, 2017, Comparative and Veterinary Medicine
Prostate cancer (PCa) is the most common malignant neoplasm among men in Western countries and the second leading cause of cancer mortalities after lung cancer. It is expected that by 2016, 180,890 men will be diagnosed with prostate cancer and 26,120 will die due to the disease. One of the most frequent complications of prostate cancer in patients is bone metastasis. Osteoblastic bone metastasis is the predominant finding at sites of skeletal metastases. Understanding the pathogenesis of prostate cancer progression and bone metastasis and targeting these processes are very important to control this aggressive disease. The main objectives of this work were to identify the role of signaling pathways that have shown to be upregulated in prostate cancer, evaluate a histone deacetylase inhibitor in treatment of prostate cancer metastasis and develop an osteoblastic PCa model for further understanding the molecular mechanisms of bone metastases. Intensive studies have been performed for better understanding the role of various signaling pathways in PCa progression and metastasis. Importantly, gastrin-releasing peptide receptor (GRPr) signaling was shown to be upregulated in human prostatic intraepithelial neoplasia (PIN), invasive prostatic carcinoma and related skeletal metastases. Our objective in this study was to determine the importance of this signaling in the pathogenesis of PCa progression. By activation of GRPr signaling using bombesin (BBN), there was an increase in proliferation and migration of canine prostate cancer cells. GRPR signaling also modulated the expression level of genes that are implicated in epithelial-mesenchymal transition (EMT), growth, invasion and metastasis of PCa. Histone deacetylase inhibitors (HDACi) are a class of therapeutics that can prevent tumor growth and induce differentiation and apoptosis in a wide group of cancers. AR-42, a HDACi, was shown to be efficient against multiple myeloma, lung cancer and hepatocellular carcinoma. In this study, we evaluated AR-42 as an anti-metastatic drug against canine prostate cancer. AR-42 decreased the mRNA expression level of anoikis resistance and osteomimicry genes in vitro. AR-42 declined the incidence of xenograft bone metastases and tumor growth and increased apoptosis and stemness of metastatic tumors. Osteoblastic bone metastasis is very common finding in PCa patients. During PCa progression, cancer cells acquire osteomimicry properties that facilitate their metastasis and support their proliferation and survival in the bone microenvironment. The pathogenesis of osteoblastic bone metastasis and osteomimicry is still not well understood. For this reason, we developed and characterized a novel canine prostatic cancer cell line (LuMa) that had osteomimicry properties and induced osteoblastic bone metastasis in vivo. The predominant sites of LuMa cells metastasis were bone, brain and adrenal glands.

Committee:

Thomas Rosol (Advisor); James DeWille (Committee Member); Beth Lee (Committee Member); Ahmad Shabsigh (Committee Member)

Subjects:

Animal Diseases; Animal Sciences; Biology; Medicine; Molecular Biology; Oncology; Pathology; Toxicology; Veterinary Services

Keywords:

Canine Prostate Cancer, Metastasis, Osteoblast Bone Metastasis, HDACi, AR-42, EMT, GRPR

Moreno Torres, Karla IrazemaThe Wildlife-Livestock Interface of Infectious Disease Dynamics: A One Health Approach
Doctor of Philosophy, The Ohio State University, 2016, Comparative and Veterinary Medicine
Surveillance for wildlife diseases is critical to our understanding of the emergence, transmission, persistence and control of infectious diseases at the interface of humans, domestic animals, and wildlife populations. Neospora caninum is a protozoan parasite capable of infecting a wide range of canid and ungulate species. The importance of the disease relates to economic losses, mainly derived from endemic or epidemic abortions in cattle. In the United States, coyotes and dogs are believed to be the main definitive hosts and white-tailed deer and cows are the main intermediate hosts. Our overall aim was to better understand the wildlife-livestock interface of N. caninum in natural settings. First, we estimated the true prevalence of N. caninum in three ruminant species by using Bayesian inference. We identified and discussed differences between apparent and true prevalence (TP). Differences in TP for some species suggest differences in the epidemiology of N. caninum for these co-located populations. Second, we evaluated the environmental phase of N. caninum shed in wild canid scats. Results suggested that the role of this environmental phase in the transmission to ruminants is likely minor. Finally, we evaluated the role of host species heterogeneity in the epidemiology of N. caninum circulating in a community. We identified differences in the patterns of immunity, age structure, and maternal and/or fetal antibody duration in three intermediate (ruminant) host species. Also, we estimated the species-specific contributions to the persistence of this pathogen in a community. This research was approached from the One Health perspective and provided a better understanding of N. caninum dynamics at the wildlife-livestock interface in an ecosystem.

Committee:

Rebecca Garabed (Advisor); Mark Moritz (Committee Member); Barbara Wolfe (Committee Member); William Saville (Committee Member)

Subjects:

Animal Diseases; Applied Mathematics; Biology; Biostatistics; Computer Science; Conservation; Cultural Anthropology; Ecology; Environmental Health; Epidemiology; Geographic Information Science; Health Sciences; Livestock; Parasitology; Veterinary Services; Wildlife Conservation; Zoology

Keywords:

multi-host parasites; Neospora caninum; wildlife-livestock interface; infectious disease modeling; disease ecology; epidemiology; One-Health; community; human dimensions; prevalence; wildlife conservation; multidisciplinary; complexity; parasitology

Barragan, Adrian AEFFECT OF CALVING MANAGEMENT PRACTICES ON STILLBIRTH IN HOLSTEIN DAIRY COWS WITH EMPHASIS IN CONFINEMENT SYSTEMS
Master of Science, The Ohio State University, 2015, Comparative and Veterinary Medicine
The objectives of the present study were to: (1) assess the effectiveness (quantity and quality of data) of an application (APP) for hand-held smart-devices to collect calving related events, and (2) assess compliance with calving practices (colostrum administration and time in labor) in Holstein dairy cows. Calving personnel (n = 23) from six large dairy farms (range: 900-5,000 cows) participated in the study. Participants received training (a workshop regarding calving management practices and functioning of the APP) prior to recording events. Pre- and posttest evaluations were administrated to measure the gain in knowledge of calving personnel. Calving personnel recorded calving-related events (n = 323) using the APP during 7 days after training. Calving personnel reported that the information provided during the training was relevant (agree = 14.3% and strongly agree = 85.7%) and of great immediate use (agree = 33.3% and strongly agree = 66.7%). The presented materials and hands-on demonstrations substantially increased (P < 0.05) the knowledge level of the attendees by 23.7 percentage points from pre- to posttest scores. The APP recorded 52% more records than traditional on-farm records under field conditions, and integrated multiple calving-related data, such as dam information (e.g., date-time of calving), colostrum management (e.g., timing, quality, and quantity) and newborn calf (e.g., presentation, vigor), with personnel performance (including shift change). The follow-up assessment with participants revealed that the APP was easy to use (91.3%) and that they would keep using it (100%). Furthermore, the records collected by the APP could be used to assess the quality of records (i.e., missing and incorrect data) and calving personnel compliance with calving management practices (i.e., recording time in labor and timing of feeding first colostrum). Frequency of incorrect (r=0.77) and missing (r=0.76) data were positively correlated with the calvings:personnel ratio per day. Furthermore, calving personnel compliance with recording labor length for the dam and time from birth to first colostrum administration to the calf was significantly (P < 0.05) different within and between herds. Additionally, the proportion of stillbirth was significantly higher (P < 0.05) during the night work shift (11%) compared to the day work shift (2.8%). Dairymen, consultants, and veterinarians often trouble-shoot calving-related losses (e.g., stillbirth) within herds; however, the lack of meaningful records makes it difficult to make meaningful corrective measures. These results substantiated the great variation in compliance with calving management practices within and between dairy farms. Furthermore, the APP may serve as a tool to monitor, in real time, the prevalence of stillbirth (e.g., day vs night shifts) and personnel compliance with calving protocols (e.g., colostrum, time to intervention). This will allow decision-makers to adjust or pre-plan the management (calvings:personnel ratio) according to actual calving rate to improve the overall quality of data (frequencies of incorrect and missing) and calf well-being (survival and performance).

Committee:

Gustavo Schuenemann (Committee Chair); Jeffrey Workman (Committee Member); Katy Proudfoot (Committee Member); Santiago Bas (Committee Member)

Subjects:

Agricultural Education; Animal Diseases; Veterinary Services

Keywords:

Dairy cattle, calving personnel, application, records, stillbirth

Wallace, Bethany FCoyote Spatial and Temporal Use of Recreational Parklands as a Function of Human Activity within the Cuyahoga Valley, Ohio
Master of Science, University of Akron, 2013, Biology
In recent decades, the urban landscape has been infiltrated by a species once considered to be intolerant of human activity. The coyote has become one of the largest and most successful carnivore species to inhabit human dominated landscapes throughout North America. Parks and green spaces are important and heavily used habitats for humans and wildlife within urban landscapes but remain a relatively understudied component of urban coyote habitat. Concerns for human and pet safety have resulted in the need to understand the spatial and temporal relationship between humans and coyotes in recreational parklands. We examined the potential conflict that exists between coyotes and humans in recreational parklands by investigating the temporal relationship of humans and coyotes along designated recreational trails. In addition, we also examined the spatial relationship of coyotes in proximity to trails. Specifically, we predict that coyotes will shift their activity to more nocturnal periods, and avoid areas of intense human use, particularly designated recreational trails, as a function of human activity occurring within the study area. In order to test this relationship, human and coyote activity was quantified within the Cuyahoga Valley region of northeast Ohio from 2009 through 2012. The study area is 14,052 hectares of public land maintained by the Cuyahoga Valley National Park and adjoining Cleveland Metroparks, and Metro Parks, Serving Summit County. It is located within the Cuyahoga River Watershed in Northeast Ohio between the cities of Cleveland in the north and Akron to the south. The study area receives over 2.8 million visitors a year, and has over 120 kilometers of designated recreational trails. Human use was monitored throughout the study area with infrared trail monitors installed at designated trail heads in 2012, and supported with data collected from traffic monitors installed in parking lots from 2008-2012. As expected, human activity within the Cuyahoga Valley park region was greatest during diurnal periods with the least amount of human activity occurring during nocturnal periods. This pattern was consistent across seasons as defined by coyote life history cycles. Annual human use was highest during the pup rearing season (April-August), and lowest during the breeding season (January-March). To quantify coyote activity, we collected data on 36 radio collared individuals in the Cuyahoga Valley park region. Coyotes were captured during three separate trapping seasons between the months of October and January in 2009, 2010 and 2011 by a professional wildlife trapper. We used padded foothold traps and live catch cable restraints. For trapping purposes, the study area was divided into a north, central, and south section, and we attempted to distribute radio collars evenly by sex in each of these areas. Once an animal was captured, it was removed from the field to avoid interactions with the public and domesticated animals and processed by a veterinarian. Care and use of research animals was approved by the University of Akron&#x2019;s Institutional Animal Care and Use Committee (IACUC #11-2B). Radiolocations of VHF-collared animals were determined by triangulation at 15-30 minute intervals during approximately 12 hour tracking shifts overnight and throughout the day. GPS collars were deployed for 45-72 weeks from the date that it was placed on an animal, at which time the preset drop-off mechanism fired and the collar was retrieved and refurbished. GPS locations were recorded every 90 minutes at night and every 3-5 hours during the day. Once per week the schedule was reversed to increase the number of diurnal locations. Distance to nearest designated trail was calculated for each coyote location within an individuals home range and coyote activity was measured as the rate of travel between sequential locations. Our results were consistent with those of other researchers in urban areas who found that coyote activity varied by diel period with most coyote activity occurring during nocturnal periods. This suggests that coyotes may be avoiding the risks associated with encountering humans within the study area through behavioral modifications. Coyote trail proximity was highly variable individually and did not show a general pattern within the population as a whole. Resident coyotes shifted their locations further away from trails during the day, which coincides with increased human activity, and shifted closer to trails during nocturnal periods when human activity was the lowest. Despite this overall pattern, it was not consistent among individual resident coyotes and could potentially be explained by differing patterns of visitation by humans to the particular trails in which these animals encounter or simply individual variation within the population of coyotes that we studied. In stark contrast to resident coyotes, transients did not exhibit general shifts in their location relative to trails across a 24 hour period. In general, transient coyotes were located closer to trails through-out the day than resident coyotes. The nomadic nature of transient coyotes may explain their relative proximity to trails as travel routes where they can move quickly and avoid encounters with territorial resident coyotes. The potential for conflict between humans and coyotes will exist wherever coyotes persist. We found significant variation among individual coyotes and the overall generalizations about their activity and spatial patterns may oversimplify complex behavioral patterns that can vary between individuals and family groups. Management of coyotes should recognize that not all coyotes have the same potential for conflict with humans and pets. Normal established trail systems rarely access all of the locations that visitors want to go, and the result is the establishment of visitor-created or informal trails. The ability of a coyote to avoid an encounter with humans on recreational trails is dependent upon predictable human activity in time and space. Off -trail human activity, or the use of undesignated trails can lead to unavoidable encounters between humans and coyotes and significantly increase the potential for negative interactions. For coyotes in the Cuyahoga Valley park region, the pup rearing season coincided with the greatest amount of human use and is the season most often associated with increased aggression, especially towards other canids as coyotes defend territory, mates, and pups. Clearly marked and designated trail systems, in combination with strict prevention of off-trail use by park visitors, will help avert unwanted encounters between coyotes and humans, and should be a priority of park managers and law enforcement officials. In addition, rigid enforcement of pet-leash laws, particularly during seasons when coyotes are known to be most aggressive will reduce the likelihood of a conflict.

Committee:

Stephen Weeks, Dr. (Advisor); Gregory Smith, Dr. (Committee Member); Randall Mitchell, Dr. (Committee Member); Stanley Gehrt, Dr. (Committee Member)

Subjects:

Animal Diseases; Animal Sciences; Animals; Area Planning and Development; Behavioral Sciences; Behaviorial Sciences; Biology; Conservation; Ecology; Forestry; Geographic Information Science; Natural Resource Management; Wildlife Conservation; Wildlife Management

Keywords:

coyote; canis latrans; cuyahoga valley national park; Metro Parks, Serving Summit County; Cleveland Metroparks; coyote activity; coyote and recreation; coyote and trails; urban carnivore; coyote home range; Ohio coyote; coyote serology; coyote mortality

Rutt, Julianne EileenMolecular Analysis Of The Epiphyseal Growth Plate In Rachitic Broilers: Evidence For The Etilogy Of The Condition
Master of Science, The Ohio State University, 2008, Animal Sciences
There is a lack of data in the literature concerning calcium-deficient rickets, which requires recognition due to to the economic and welfare concerns of leg weakness in broilers, as well as being an ideal disease model to study the effect of calcium on chondrocyte maturation. Broilers were raised on an adequate and calcium-deficient diet, and the rickets condition was confirmed using visual assessment, histology, and blood plasma analysis. The expression of known chondrogenic genes as well as genes from a previous rickets-based microarray was analyzed using real-time PCR with control and deficient growth plate chondrocytes. Indian hedgehog (Ihh) was decreased in rickets, parathyroid-hormone receptor (PTHR-1) was increased in rickets, and parathyroid hormone related-peptide (PTHrP) showed no difference. The calcium-sensing receptor had a 20-fold increased expression in rickets. Three of the four bone morphogenic proteins (Bmp) analyzed (-2, -4, -6) and both Bmp receptors were expressed lower in rickets. Eukaryotic elongation factor 1-δ showed a trend of being decreased in rachitic plates, and annexin-V and fibrillin-I were decreased in rickets. ATP analysis of the growth plates using a luciferase assay revealed a trend of ATP being increased in the rickets growth plates. An attempt at developing an in vivo chondrocyte cell culture model was unsuccessful primarily due to lack of cell proliferation and contamination.

Committee:

David Latshaw, J. (Advisor); Kichoon Lee (Committee Member); Pasha Lyvers-Peffer (Committee Member)

Subjects:

Agriculture; Animal Diseases

Keywords:

chondrocytes; cell culture; broiler chickens; leg abnormalities; rickets; chondrogenic gene expression

Somineni, Hari KrishnaPhysical exercise training but not metformin attenuates albuminuria and shedding of ACE2 in type 2 diabetic db/db mice
Master of Science (MS), Wright State University, 2013, Pharmacology and Toxicology
Angiotensin II (Ang II), a potent vasoconstrictor cleaved from Ang I, is responsible for renal damage in diabetes. Angiotensin converting enzyme 2 (ACE2) is highly expressed in the kidney and has been shown to be renoprotective by degrading Ang II to Ang-(1-7). A Disintegrin and Metalloproteinases (ADAMs) were recently identified as an ectodomain sheddases of transmembrane proteins. ADAM17 mediated shedding of renal ACE2 could contribute to the pathogenesis of diabetic nephropathy. In our previous study, rosiglitazone treatment normalized hyperglycemia and improved renal injury by preventing ACE2 shedding. The aim of this study is to test the hypothesis that improved glucose homeostasis with exercise and/or metformin attenuates albuminuria, renal ADAM17 protein and prevents shedding of ACE2 in db/db mice. Seven week old normal and db/db mice were subjected to physical exercise training and/or metformin treatment (150 mg/kg/day) for 10 weeks. Exercised mice ran on a mouse forced exercise walking wheel system for 1 hr a day for 7 days a week at a speed of 8 meters/minute. At juvenile stages (6 week old), db/db mice demonstrated higher levels of blood glucose, urinary albumin and ACE2 excretion. Urinary ACE2 is enzymatically active and 20 kDa shorter as demonstrated by immunoblotting. Renal ADAM17 and ACE2 protein levels were significantly upregulated in db/db mice compared to non-diabetic controls. In diabetic kidney, upregulated ADAM17 and ACE2 proteins co-localized in the tubular cortex. However, physical exercise training significantly attenuated blood glucose, urinary albumin and ACE2 excretion of db/db mice throughout the study period, whereas metformin treatment was effective in lowering hyperglycemia only in the initial stages of diabetes. The increased renal ADAM17 protein levels in db/db diabetic mice were normalized by exercise training but not by metformin. In addition, exercise training reduced plasma triglycerides and enhanced insulin levels of db/db mice. The combination of exercise and metformin was effective against lowering plasma glucagon. Results demonstrated a significant association between blood glucose, urinary albumin, plasma insulin, glucagon and triglycerides with urinary ACE2 excretion. In conclusion, co-localization of ADAM17 with ACE2 suggests a possible interaction in diabetic kidney. Exercise training with or without metformin prevented shedding of renal ACE2 by attenuating ADAM17 protein. Elevated plasma insulin by exercise could be responsible for improved glucose homeostasis, at least in partial. Urinary ACE2 could serve as a prognostic tool in the progression of kidney damage and its attenuation by exercise may partially contribute to its renal protection.

Committee:

Khalid Elased, Pharm D, Ph.D. (Advisor); Gregory Boivin, D.V.M. (Committee Member); Courtney Sulentic, Ph.D. (Committee Member)

Subjects:

Animal Diseases; Animal Sciences; Pharmacology

Keywords:

Urinary ACE2; Albuminuria; Biomarkers; Diabetic nephropathy; ADAM17; Timp3; Collagen; PAS staining; type 2 diabetes; db/db mice; Physical exercise training; Metformin

Swan, Kathie LanetteSorption Characteristics of Veterinary Ionophore Antibiotics Monensin and Lasalocid and Soil Clay Constituents Kaolinite, Illite and Montmorillonite
Master of Science, University of Toledo, 2012, Geology

Monensin and Lasalocid are veterinary ionophore antibiotics used for therapeutic and non-therapeutic treatment of livestock. Manure containing un-metabolized compounds is in turn used as beneficial amendment for agricultural crops, thus, these compounds may be available for transport through soils. These antibiotics have been detected in run-off, surface water, and groundwater and may be toxic to soil and aquatic biota. This research focuses on adsorption mechanisms of Monensin (MON) and Lasalocid (LAS) to clay constituents common in agricultural soils. Methods were developed to extract these compounds from water, soil, and sludge and for subsequent analysis using liquid chromatography tandem mass spectrometry. Batch equilibrium experiments indicated that Monensin and Lasalocid have unique adsorption mechanisms that are highly pH-dependent. Predicted order of adsorption strength and desorption capabilities were not observed.

Illite (ILL) had optimal adsorption conditions for and showed strong affinity for both LAS and MON. Desorption was very high in the competitive study. Kaolinite (KAO) showed moderate adsorption and desorption was nearly twice as high when the compounds were paired. Montmorillonite (MTM) displayed low adsorption and desorption was higher in the non-competitive study. More retention of LAS by MTM was apparent in the competitive study. Manure (MAN) used in this study did not show a strong affinity for the MON and LAS complexes. Desorption from this manure was low, particularly for LAS in the competitive study. Ottawa sand (OTS) showed little adsorption as was expected. Desorption was generally moderate, except for MON which was high, particularly in the non-competitive study. Soil (GLRI) adsorption was generally high and there was a one order of magnitude difference between the non-competitive and competitive studies.

Adsorption was rapid and partially irreversible unto all sorbents indicating that portions of these compounds may remain in soils, possibly toxic to biota until degradation occurs. Remaining adsorbed compound has limited availability for transport via runoff to surface waters, leaching to groundwater, transformation, and/or bioaccumulation. More research regarding the fate of Monensin and Lasalocid is necessary to fully understand their behavior in soil, particularly in Northwest Ohio which is a large agricultural region spatially proximate to the Great Lakes.

Committee:

Alison Spongberg, PhD (Committee Chair); David Krantz, PhD (Committee Member); James Martin-Hayden, PhD (Committee Member)

Subjects:

Agriculture; Animal Diseases; Environmental Geology; Environmental Management; Environmental Science; Geochemistry; Geology; Land Use Planning; Livestock; Soil Sciences

Keywords:

Veterinary Antibiotics; Monensin; Lasalocid; Clays; LC-MS/MS

Breit, Megan NBiologic Activity of the Novel SINE Compound KPT-335 Against Canine Melanoma Cell Lines
Master of Science, The Ohio State University, 2014, Veterinary Clinical Sciences
Background: Exportin 1 (XPO1, also known as CRM1), is a protein responsible for the export of over 200 target proteins out of the nucleus. XPO1 is upregulated in several human cancers and its expression is also linked to the development of chemotherapy resistance. Recent studies using both human and murine cancer cell lines have demonstrated that XPO1 is a relevant target for therapeutic intervention. The present study sought to characterize the biologic activity of an orally bioavailable selective inhibitor of nuclear export (SINE), KPT-335, against canine melanoma cell lines as a prelude to future clinical trials in dogs with melanoma. Results: We evaluated the effects of KPT-335 on 4 canine malignant melanoma cell lines and found that KPT-335 inhibited proliferation and induced apoptosis of treated cells. Additionally, KPT-335 downregulated XPO1 protein while inducing a concomitant increase in XPO1 messenger RNA. Lastly, KPT-335 treatment of cell lines induced the expression of the tumor suppressors p53 and p21, with enhanced nuclear localization. Conclusion: KPT-335 demonstrates biologic activity against canine melanoma cell lines at physiologically relevant doses, suggesting that KPT-335 may represent a viable treatment option for dogs with malignant melanoma.

Committee:

Cheryl London, DVM, PhD (Advisor); William Kisseberth, DVM, PhD (Advisor); Emma Warry, BVSc (Hons) (Committee Member)

Subjects:

Animal Diseases; Animal Sciences; Veterinary Services

Keywords:

Canine; Melanoma; CRM1; XPO1; SINE; KPT

Dudley, Alicia AAn Investigation of the Multifaceted Platelet Dysfunction in Dogs with Naturally-Occurring Chronic Kidney Disease
Master of Science, The Ohio State University, 2014, Comparative and Veterinary Medicine
Bleeding is a complication of chronic kidney disease (CKD) in humans and can occur despite normal coagulation times and platelet counts. These abnormalities are caused, in part, by platelet dysfunction and abnormal platelet-vessel wall interactions. Dogs with experimentally induced CKD have prolonged mucosal bleeding times, however this test is variable and error prone. In dogs with naturally occurring CKD, coagulation defects and platelet dysfunction have not been evaluated using new point-of-care tests of platelet function and global coagulation. Our objective was to compare platelet function between healthy dogs and dogs with CKD using the PFA-100 and thromboelastography (TEG) and to determine if changes in these tests can be explained by alterations in platelet GPIb and GPIIb-IIIa expression, membrane receptors for vWF and fibrinogen, respectively or in changes in platelet activation as determined by platelet P-selectin expression. Blood samples from 11 dogs with naturally occurring CKD and 10 healthy control dogs were collected. Routine CBC with platelet count, serum biochemistry and urinalysis with urine protein to creatinine ratio were performed in both groups. Platelet function was assessed by measuring PFA-100 closure times (CT) using collagen and epinephrine (Col+EPI) or collagen and adenosine diphosphate (Col+ADP) agonists. Reaction time (R), clot formation time (K), alpha-angle, maximal amplitude (MA) and global clot strength (G) TEG variables were analyzed. Soluble coagulation factor function testing was performed including PT, aPTT, fibrinogen concentration and AT activity. Platelet GPIb, GPIIb-IIIa and P-selectin expression was assessed by flow cytometry and expressed as mean fluorescence intensity (MFI). Hematocrit was significantly decreased in CKD dogs (p < 0.0001). Platelet counts were not different between groups (p = 0.57). Dogs with CKD had significantly prolonged PFA-100 Col+ADP CT compared to healthy dogs (p = 0.01). No significant difference in Col+EPI CT was found between healthy and CKD dogs. There was a significant increase in TEG MA (p < 0.01) and G (p = 0.01) and a significant decrease in K-time (p = 0.035) in dogs with CKD compared to healthy controls. The remaining TEG variables (R, and angle) were not significantly different between CKD and healthy dogs. CKD dogs had increased platelet GPIIb-IIIa and P-selectin MFI compared with control dogs (p = 0.01 and 0.03 respectively). There was no difference in GPIb MFI between groups. No correlation was found between platelet surface receptor expression and any TEG value or PFA-100 closure times. Dogs with CKD appear to have platelet dysfunction despite normal platelet counts. However, despite platelet dysfunction, these patients are hypercoagulable based on their significantly elevated MA and G TEG values. This discrepancy may be explained by the significantly decreased hematocrit and significantly increased fibrinogen concentrations in CKD dogs. However, platelet receptor expression cannot be used to explain changes in platelet function and changes in whole blood coagulation identified in these patients. Additional studies are needed to identify the underlying platelet defect(s) in dogs with CKD and what role they play in whole body coagulation, as well as their clinical significance.

Committee:

Julie Byron, DVM, MS, DACVIM (Advisor); Mary Jo Burkhard, DVM, PhD, DACVP (Committee Member); Emma Warry, BVSc (HONS), DACVIM (Committee Member)

Subjects:

Animal Diseases

Keywords:

Platelet; Coagulopathy; Hypercoagulable; Kidney; PFA; TEG; GPIb; GPIIb-IIIa; P-selectin; Fibrinogen

Hall, Melanie JPharmacology of the GLP-1 Analog Liraglutide in Healthy Cats
Master of Science, The Ohio State University, 2014, Comparative and Veterinary Medicine
GLP-1 is an intestinal hormone that induces glucose-dependent stimulation of insulin secretion while suppressing glucagon secretion and increasing beta cell mass, satiety and gastric-emptying time. Liraglutide is a fatty-acid derivative of GLP-1 with a protracted pharmacokinetic profile that is used in people for treatment of type II diabetes mellitus and obesity. The aim of this study was to determine the pharmacokinetics and pharmacodynamics of liraglutide in healthy cats. Hyperglycemic clamps were performed on days 0 (HGC) and 14(LgHGC) in eight healthy cats. Liraglutide was administered subcutaneously (0.6 mg/cat) once daily on days 8 through 14. Compared to the HGC (mean ± SD; 455.5 ± 115.8 ng/L), insulin concentrations during LgHGC were increased (760.8 ± 350.7 ng/L; P = 0.0022), glucagon concentrations decreased (0.66 ± 0.4 pmol/L during HGC vs. 0.5 ± 0.4 pmol/L during LgHGC; P = 0.0089) and there was a trend towards an increased total glucose infused [median (range) of 1.61 (1.11 – 2.54) g/kg during HGC vs. 2.25 (1.64 – 3.10) g/kg during LgHGC; P = 0.087]. Appetite reduction and decreased body weight (9% ± 3; P=0.006) were observed in all cats. Liraglutide has similar effects and pharmacokinetics profile in cats to those reported in people. With a half-life of approximately 12 hours, once daily dosing might be feasible, however significant effects on appetite and weight loss may necessitate dosage or dosing frequency reductions. Further investigation of liraglutide in diabetic cats and overweight cats is warranted.

Committee:

Chen Gilor, DVM, PhD, DACVIM (Advisor); Susan Johnson, DVM, MS, DACVIM (Committee Member); Christopher Adin, DVM, DACVS (Committee Member); Jeffrey Lakritz, DVM, DACVIM (Committee Member)

Subjects:

Animal Diseases; Animal Sciences; Animals; Endocrinology; Veterinary Services

Keywords:

feline, diabetes, insulin, glucagon, incretin

Whalin, Rebekah ChristineThe Detection of Mycoplasmas in Migratory Birds
Bachelor of Arts, Miami University, 2009, College of Arts and Sciences - Zoology

Mycoplasma is a genus of bacteria that lack a cell wall and are sometimes found as pathogenic organisms in humans and animals. Mycoplasma gallisepticum has been isolated in a number of economically significant birds, notably turkeys and chickens and causes chronic respiratory disease, reduced feed efficiency, decreased growth and decreased egg production (2,5). M. gallisepticum has not been studied extensively in smaller birds such as cardinals (Cardinalis cardinalis) and catbirds (Dumetella carolinensis), and these small migratory birds are the species on which this research was focused. There is concern that the wild birds may transmit M. gallisepticum infections to commercial flocks, causing economic losses due to disease (7). Deceased birds as well as live specimens were analyzed. Samples were plated on SP4 with thallium acetate. Extensive DNA analysis was performed on dead bird tissues after culturing yielded no growth. PCR was used to systematically amplify 16S rDNA to allow identification of variable regions with both genus- and species-specific sequences (12). After PCR the products were run through gel electrophoresis, and bands at 1500 bp were identified. The DNA was extracted from the gel and Escherichia coli DH5α cells were transformed for blue/white screening. White colonies were scraped from the plates and allowed to grow in broth media. The DNA from these cultures was prepared using miniprep digestion. After ensuring amplification of the desired 16S DNA through gel electrophoresis the samples were purified and sequenced. There was no growth of either live or dead bird samples. The DNA extraction and amplification performed on the dead bird tracheas produced the desired 16S amplification, and white colonies in blue/white screening. Sequences yielded flat lines, indicating that sequencing failed, and others resulted in sequences similar for Mycoplasma amphroiforme, Mycoplasma pirum, Lentiviral transfer vector and expression vector pHF5Na. Culturing of mycoplasmas was unsuccessful for both live bird swabs as well as plating of tracheal specimens. None of the DNA sequencing yielded relevant results, producing sequences instead that indicated cross contamination or failing to sequence the sample. From these results the hypothesis that mycoplasmas constitute normal flora in the respiratory tracts of small migratory birds is not supported.

Committee:

Mitchell Balish, PhD (Advisor); Kelly Abshire, PhD (Committee Member); Paul Schaeffer, PhD (Committee Member)

Subjects:

Animal Diseases; Microbiology; Zoology

Keywords:

mycoplasma; Mycoplasma gallisepticum; migratory birds; birds

Voris, Hillary ClaireCharacterization of Advertisements for Puppies Sold Online: Determinants of Cost and a Comparison with Parent Club Breeders
Master of Science, The Ohio State University, 2010, Veterinary Preventive Medicine
Each year, hundreds of thousands of puppies are bred and sold in the United States. The newest market for puppy sales is the Internet. Consumers can view multiple advertisements for puppies in just minutes but there is no information available regarding what information is standard in online advertisements. In addition, within a breed, puppies vary widely in cost. It is difficult for a consumer to determine why one puppy might cost so much more than another. The goal of this project was to characterize the online market for puppies by documenting the contents of Internet ads for five common breeds (Labrador Retriever, Yorkshire Terrier, Bulldog, Boxer and Shih Tzu) over a period of three months. Traditional breeders, for example American Kennel Club (AKC) breeders, have been around for generations. The services these breeders provide are well documented. Internet breeders are less well understood. The second part of this study compared puppies sold by Internet breeders with puppies sold by AKC Parent Club breeders. In a period of 14 weeks, 3,485 advertisements were reviewed. Small breed puppies were most frequently advertised with 35.2% (1,228/3485) of advertisements for Yorkshire Terriers and 23.0% (802/3485) for Shih Tzus. Almost one quarter of Internet breeders 768/3,474 (22.2%) advertised four or more different dog breeds. Champion bloodlines increased the cost of a puppy of all breeds. AKC Parent Club breeders 21/25 (84%) were more likely to mention breed-specific health screening tests when compared to Internet breeders 7/25 (28%). The Internet is a large and growing source for puppies. Currently, breeders who sell puppies online directly to consumers are not subject to any type of regulation. As this industry grows, some type of oversight will be important. The most important difference between Internet and AKC Parent Club breeders is the knowledge and use of breed-specific health screening tests. Internet breeders are less likely to perform these screening tests on their breeding dogs and may breed dogs with undesirable heritable health risks.

Committee:

Linda Lord (Advisor); Paivi Rajala-Schultz (Committee Member); Thomas Wittum (Committee Member)

Subjects:

Animal Diseases; Animals; Epidemiology

Keywords:

puppies; cost; health; breed-specific screening tests; breeders; Internet

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