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Amino Acid-Fermenting Bacteria from the Rumen of Dairy Cattle - Enrichment, Isolation, Characterization, and Interaction with Entodinium caudatum

Gano, Jacqueline Maxine
http://rave.ohiolink.edu/etdc/view?acc_num=osu1374146958

Abstract Details

2013, Master of Science, Ohio State University, Animal Sciences.
Excess ammonia emissions are a major concern for the dairy industry due to the detrimental impact ammonia emissions have on the environment and wastage of dietary nitrogen. Hyper-ammonia-producing bacteria (HAB) and protozoa in the rumen are the major contributors of excessive ammonia excretions from cattle. Besides Clostridium aminophilum, C. sticklandii, and Peptostreptococcus anaerobius, little is known about the HAB present in the rumen. In addition, rumen protozoa prey on bacteria and other microbes, excreting considerable amounts of amino acids and/or peptides that could promote the growth of HAB. In addition, inhibition of HAB by plant secondary metabolites may ultimately reduce ammonia production by HAB, thereby lowering excess nitrogen emissions. The studies presented in this thesis investigate HAB characterizations and interactions. In the first study, mixed microbes were obtained from the rumen of three fistulated dairy cows and further enriched and isolated for amino acid-fermenting bacteria. As a result, new isolates displayed high rates of ammonia production, ranging from 0.87 to 2.45 mg N/dL, and identified through 16S rRNA gene sequencing as a Bacillus sp. and Proteus mirabilis. In the second study, HAB enrichment cultures were co-cultured with an Entodinium caudatum culture. The co-culturing experiment was conducted with or without a feed substrate for E. caudatum and Micrococcus luteus to assess the impact of feeding the protozoan. Ammonia concentrations were higher in the E. caudatum alone treatments, both with and without the addition of the feed substrate compared with HAB alone or co-culture of HAB and E. caudatum, with 20.5 &#xb1; 0.8, 18.5 &#xb1; 0.2, 23.9 &#xb1; 0.3, and 23.2 &#xb1; 1.1 mg ammonia N/dL in treatment groups E. caudatum with feed substrate, E. caudatum without feed substrate, E. caudatum with feed substrate and with M. luteus, and E. caudatum without feed substrate but with M. luteus, respectively. Ammonia concentration was also significantly (P < 0.05) increased by M. luteus addition in the E. caudatum alone treatment group without feed substrate but with M. luteus. In the third study, HAB in enrichment cultures were examined for inhibition by varying plant secondary metabolites in terms of ammonia concentration. Results indicate that carvacrol, origanum oil, clove oil, and vanillin all successfully (P < 0.01) reduced ammonia concentration 24 h post incubation both in the presence and absence of a feed substrate. Overall, results indicate the presence of additional amino acid-fermenting bacteria in the rumen, capable of rapid ammonia production. These amino acid-fermenting bacteria, when grown in co-cultures with E. caudatum may interact with protozoa present within the rumen. These amino acid-fermenting bacteria are also sensitive to certain plant secondary metabolites, therefore decrease in ruminal ammonia concentration and shifts in ruminal microbe populations may be achieved through dietary supplementation with some of these plant secondary metabolites.
Zhongtang Yu, Dr. (Advisor)
Jeffrey Firkins, Dr. (Committee Member)
Macdonald Wick, Dr. (Committee Member)
128 p.
Animal Sciences
Rumen, Hyper-ammonia-producing bacteria, Ammonia

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Citations

  • Gano, J. M. (2013). Amino Acid-Fermenting Bacteria from the Rumen of Dairy Cattle - Enrichment, Isolation, Characterization, and Interaction with Entodinium caudatum [Master's thesis, Ohio State University]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=osu1374146958

    APA Style (7th edition)

  • Gano, Jacqueline. Amino Acid-Fermenting Bacteria from the Rumen of Dairy Cattle - Enrichment, Isolation, Characterization, and Interaction with Entodinium caudatum . 2013. Ohio State University, Master's thesis. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=osu1374146958.

    MLA Style (8th edition)

  • Gano, Jacqueline. "Amino Acid-Fermenting Bacteria from the Rumen of Dairy Cattle - Enrichment, Isolation, Characterization, and Interaction with Entodinium caudatum ." Master's thesis, Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1374146958

    Chicago Manual of Style (17th edition)

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This open access ETD is published by The Ohio State University and OhioLINK.