Recipient Organization
UNIVERSITY OF VERMONT
(N/A)
BURLINGTON,VT 05405
Performing Department
Animal Science
Non Technical Summary
Moose are interesting herbivores. They prefer a diet of bark, twigs and leaves from various tree species, and in the summer they consume aquatic vegetation from swamps and other waterways. During the winter, when food is scarce and lower in calories, moose can lose up to 20% of their body weight without suffering the typical health side effects. Moose are ruminants, like cows, sheep, and goats, and have a specialized four-chambered stomach which allows them to host symbiotic microorganisms to ferment the fibrous plant matter diet that is mostly indigestible to them. Little research has been done on the type of microorganisms (i.e. bacteria, methanogens, protozoa, fungi, etc) which are able to live in the dynamic rumen of the moose, or their ability to digest different types of plant matter. This project will expand our basic knowledge of the microorganisms responsible for plant matter digestion in the rumen of the moose using culturing techniques and DNA sequencing. The research goals are to identify the microorganisms present in the digestive tract of the moose (some of which may be new species or strains), to determine which of these bacterial species degrade plant matter, and to measure their cellulolytic efficiency of degrading plants. Bacteria species which are more efficient at degrading plant matter will be selected and introduced into the rumen of newborn lambs. By allowing efficient bacteria to colonize early, it is hypothesized that these lambs will gain more weight, or gain weight faster, and potentially grow wool faster than lambs in the control group. This project will have widespread applications in agriculture, food systems, waste reclamation and green energy. Animal production can be very costly, and in order to meet the challenges of increased demand for food production using fewer resources and land mass, its efficiency needs to be increased/improved. Microorganisms, by-products, or enzymes from the rumen can be used in a wide variety of systems; such as increasing animal production, using enzymatically pre-treated forage to increase digestibility for livestock, improving the ensiling process, or digesting plant biomass for bioethanol production. Through journal article publications, conference presentations, and public seminars, project findings will be disseminated to members of the public and the scientific community.
Animal Health Component
50%
Research Effort Categories
Basic
40%
Applied
50%
Developmental
10%
Goals / Objectives
My research goals are to: (1) identify the microorganisms present in the digestive tract of the moose (some of which may be new species or strains), (2) determine which of these degrade fiber, (3) measure their fibrolytic efficiency, (4) determine whether these microorganisms can be introduced into other systems to improve fiber degradation. For the last gosl, I will introduce microbes isolated from the rumen of moose into the rumen of sheep, and it is hypothesized that the bacteria from the moose will improve fiber degradation and production.
Project Methods
1. Culture bacteria using the eight moose rumen samples collected in Vermont. a) Identify isolates by sequencing the 16S rRNA gene (UVM DNA Facility), deposit sequences into GenBank (NCBI). b) Maintain fresh and frozen stocks for each isolate. Describe isolates via cell staining, oxygen tolerance, carbohydrate utilization and optimal growth parameters. c) Determine catalytic efficiency of fiber digestion using culturing techniques for a selected set of isolates that show ability to digest cellulose, cellobiose, or hemicellulose. 2. Cultivate bacteria with high cellulase enzyme efficiency, and inoculate into lambs. a) Purchase 22 neonatal lambs from local farms and house at the UVM Paul Miller Research Complex in Burlington, Vermont. One lamb per group may be discounted from the experiment for health reasons, etc., without adversely affecting statistical significance of results. b) PCR amplify the 16S gene from fresh rumen samples from all lambs prior to inoculation to determine if any bacteria are present in the rumen. If positive, high-throughput sequencing can be used to determine which bacteria are present. c) Randomly assign lambs to the inoculation group (n=11), which will receive a bacterial culture, and the control group (n=11), which will receive media. Cultures and media will be delivered using milk-replacer as a vector during one feeding/day. d) Sample the rumen at 24, 48, and 72 hours (prior to the daily re-inoculations), either by stomach tubing or rumen fistulation, then weekly for eight weeks to measure the presence of the bacteria of interest in the rumen. Samples may be sent out for high-throughput sequencing to measure any shifts in overall bacterial population over the course of the experiment, or analyzed in the lab using PCR and specific primers designed to amplify the inoculant bacteria from a mixed rumen sample. The inoculant will routinely be re-cultured from the rumen to ascertain that it is thriving. e) Measure several parameters to determine the effect of the inoculant and measure significant health changes in the animals, as animal health is of paramount importance if this bacterium is to be used as a probiotic supplement. Significant weight loss or adverse changes in wool growth or quality may indicate decreased feed intake or dietary efficiency, and may require medical intervention. f) Measure dietary efficiency using in vitro nylon mesh bags inserted into the rumen biweekly [19], and containing a sample of the diet that the lambs will be fed for the duration of the experiment. Measure volatile fatty acid production using gas chromatography in the lab, as well as rumen pH. All production/performance data will be submitted for publication in a livestock science and nutrition journal, such as the Journal of Animal Science. 3.Process samples and analyze data. a) Amplify the 16S rRNA gene of bacteria from the samples collected during Step 2 , prepare amplicon libraries and send out for Roche 454 pyrosequencing. b) Analyze DNA sequencing data, write and submit manuscripts, present data at conferences, write and submit graduate thesis.