2009 Annual Report
1a.Objectives (from AD-416)
The overall goal of this research is to develop practical pig production technologies resulting in increased nutrient utilization and gastrointestinal and manure microbial ecology modification leading to a reduction of the impact of swine production on the environment.
1) Manipulate dietary ingredients to improve nutrient utilization and reduce nutrient excretion and the production of volatile organic compounds.
2) Identify microbial populations and modify in situ microflora in the pig gastrointestinal tract to reduce the formation of volatile organic compounds.
3) Quantify the impact of dietary regimen on nutrient metabolism of the gastrointestinal tract and the whole animal.
4) Characterize and quantify the production of impact odorants in vapor phase and on particulates from production facilities, and determine how the manure matrix influences emissions of odorants in the solution phase.
1b.Approach (from AD-416)
First, dietary ingredients (corn, soybean meal, distiller dried grains, soybean meal, beet pulp, crystalline amino acids, etc.) will be manipulated to improve nutrient utilization in the animal; and reduce nutrient excretion and the emission of volatile organic compounds into the environment; second, gastrointestinal microbial populations will be identified and subsequently modified to reduce the formation of volatile organic compounds; third, the impact of dietary regimen on nutrient metabolism of the gastrointestinal tract and the whole animal will be quantified; and fourth, the production of impact odorants in vapor phase and on particulates from production facilities will be characterized and quantified, and determine how the manure matrix influences emissions of odorants in the solution phase. Additional studies will be conducted for the enhancement of energetic efficiency as a means of improving nutrient utilization in swine production systems in Objectives 1 and 3 of the current project.
Objective 1: A series of trials were conducted and completed evaluating the metabolizable energy concentration of various corn milling co-products and relating these values to analyzed ingredient composition and in vitro organic matter digestion. Data show that several co-products can be used as an alternative energy source in swine diets, but with the moderate levels of dietary fiber, they will likely have limited inclusion levels in practical feed formulation. Collaborative studies were initiated evaluating the energy value of corn milling co-products in broilers and the on the impact of diet changes on nutrient digestion adaptation.
Objective 2: Gas chromatography-olfactometry techniques have been successfully used to identify odors from swine and cattle production facilities. Application of this technique showed that the nature of odor changed with distance. At the source, key odorants included volatile fatty acids and phenol and indole compounds; 400 meters downwind, key odorants included only phenol and indole compounds, with a minor component being volatile fatty acids; while 3200 meters downwind, key odorants included indole compounds with phenol compounds being more minor.
Objective 3: Studies were conducted in growing pigs to determine the impact of low dietary fiber sources, sugar beet pulp and wheat bran, on pig growth, markers of energy metabolism, tissue mitochondrial DNA content, and the expression of genes involved in energy metabolism. Despite no differences in animal growth or feed intake, each fiber source differentially regulated energy metabolism. Adding sugar beet pulp to the diet increased serum non-esterified fatty acids and the expression of adipose triglyceride lipase in adipose tissue. Increasing dietary fiber level by adding wheat bran increased the content of mitochondrial DNA and the expression of genes involved in mitochondrial biogenesis and oxidative metabolism in intestinal tissue. This indicates that a non-soluble fiber source, such as wheat bran, increases the capacity of the intestinal tract to utilize energy metabolites. Taken together, the results of these studies suggest that different sources of fiber differentially impact energy metabolism in growing pigs.
Objective 4: Samples from different sections of the intestinal tract in pigs fed either traditional diet or one with high levels of dried distillers grain with solubles have been analyzed by fluorescence in situ hybridization for bacteria, archaea (methanogens), and eukarya, as well as total microbial counts. There were significant differences in the numbers of bacteria and methanogens in the different segments and the microbial community structure is not homogenous. This will further elucidate the relationship between diet and the microbial community response in pig and determine the different bacteria and archaea that dominate in each section of the gastrointestinal tract.
Identification of key odorants from livestock production facilities. Odors from livestock production facilities have been researched for years, but to date, there is no agreement on key chemicals responsible for "odor" generated from livestock production facilities. Using gas chromatography-olfactometry, research was successful in identifying key odors produced from swine and beef production facilities and indicating that the nature of odor changed with distance. At the source, key odorants included volatile fatty acids and phenol and indole compounds; 400 meters downwind, key odorants included only phenol and indole compounds, with a minor component being volatile fatty acids; while 3200 meters downwind, key odorants included indole compounds with phenol compounds being more minor. This data is key for personnel in the animal industry in addressing issues related to odors generated from livestock production facilities.
Weber, T.E., Kerr, B.J., Spurlock, M.E. 2008. Regulation of hepatic peroxisome proliferator-activated receptor-alpha (PPAR-a) expression but not adiponectin by dietary protein in finishing pigs. Journal of Animal Physiology and Animal Nutrition. 92(5):569-577.
Alexander, L.S., Ou, A., Cutler, S.A., Mahajan, A., Lonergan, S.M., Rothschild, M.F., Weber, T.E., Kerr, B.J., Stahl, C.H. 2008. Response to Dietary Phosphate Deficiency is Affected by Genetic Background in Growing Pigs. Journal of Animal Science. 86(10):2585-2595.
Lammers, P.J., Kerr, B.J., Weber, T.E., Bregendahl, K., Lonergan, S.M., Prusa, K.J., Ahn, D.U., Stoffregen, W.C., Dozier III, W.A., Honeyman, M. 2008. Growth performance, carcass characteristics, meat quality, and tissue histology of growing pigs fed crude glycerin-supplemented diets. Journal of Animal Science. 86(11):2962-2970.
Corzo, A., Kidd, M.T., Dozier, W.A., Kerr, B.J. 2009. Dietary Glycine and Threonine Interactive Effects in Broilers. Journal of Applied Poultry Research. 18(1):79-84.