Animal & Dairy Science: Personnel
Mark A. Froetschel
Mark A. Froetschel B.S., West Virginia University Edgar L. Rhodes Center for ADS |
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Description of Research Interests
The primary area of research interest involves measuring gastrointestinal factors that influence intake regulation in livestock. Increasing caloric intake above maintenance requirements maximizes feed efficiency and profitability of livestock. Intake regulation of ruminant species as compared to nonruminants is highly dependent on gastrointestinal fill and motile processes because of the relative amounts of fiber in the diet. There are several substances of both dietary and exocrine origin that influence motile processes of the digestive tract. The research has focused on dietary and salivary peptides that exert opioid and cholecystokinin reversible activity on reticulo-ruminal and gastric motility, incretin release and intake. In addition, the influence of silage biogenic amines on reticulo-ruminal motile process, incretins and intake is under investigation.
A second area of interest involves developing a value-added feed product that will support growth of cattle based on low-cost byproduct feeds readily available in Georgia. A feed product is being developed that contains broiler litter(45%), whole cottonseed (25%) and molasses (30%) and is fed as a supplement block to growing cattle. The product has been found to support daily gains at a cost of $.25 to .50/lb in cattle that have free choice access to marginal quality hay. Recently the product was found to be limited in protein quality and may be made even more cost effective by including a blend of ruminally undegradable protein into the feed product. Future research will explore the opportunity to use poultry byproduct meal, another regionally produced byproduct, as an economical source of ruminally undegradable protein.
Courses Taught
Feeds and Feeding (ADSC 3310): A study of the composition and properties of the important feedstuff's and the application of the basic principles of nutrition in the use of these feedstuff's in the scientific feeding of livestock (3 credit hours). Average enrollment: 50 students; class is taught during spring semesters. The course consists of lecture and laboratory periods. The laboratories are spent in the computer teaching classroom. Ration formulation using spreadsheet and least-cost programs are emphasized in the 3 h laboratory periods.
Bioenergetics (ANNU 8310): A detailed treatment of energy transformations in animals. Application of thermodynamic principles to the conservation and conversion of energy in animals. The energy values of feedstuffs as determined by various methods are discussed (2 credit hours). Average enrollment: 7 graduate students. The class is taught during alternate fall Semesters.
Selected Recent Publications
Froetschel, M. A. 1996. Bioactive peptides that regulate gastrointestinal function and intake. J. Anim. Sci. 74:2500-2508.
Froetschel, M.A., J.K. Courchaine, S.W. Nichols, H.E. Amos, and A.C. Murry, Jr. 1997. Opioid-mediated responses of dietary protein on reticular motility and plasma insulin. J. Dairy Sci. 80:511-518.
Phuntsok T., M. A. Froetschel, H. E. Amos, M. Zheng, and Y. W. Huang. 1998. Biogenic amines in silage, apparent post-ruminal passage and their relationship to digestive function and intake of cattle. J. Dairy Sci. 81:2193-2203.
Nichols, S. W., M. A. Froetschel, H. E. Amos, and L. O. Ely. 1998. Effects of fiber from tropical corn and forage sorghum on intake, digestion and performance of lactating dairy cattle. J. Dairy Sci. 81:2383-2393.
Wickliffe, J. A., M. A. Froetschel, C. A. McPeake, and H.E. Amos. 1999. Development of an economical feed product for growing cattle based on whole cottonseed, broiler litter and molasses. J. Anim. Sci. 77(Suppl. 1):1.