Dr. Duff

Dr. Glenn Duff

Associate Professor, Ruminant Nutritionist

Office: Shantz Building 217
520-621-5573
gduff@ag.arizona.edu

Degrees:

Classes Taught:

Dr. Glenn Duff grew up in southwest Iowa. He gained an appreciation for the livestock industry at an early age through active participation in FFA. His main project was raising purebred Spot hogs, which was initially started as a gilt chain. During his first year showing, Dr. Duff won Reserve Champion boar and Champion Litter in the FFA show at the Iowa State Fair. During the second year, he won Champion and Reserve Champion Boar, Champion Sow, and Champion Litter at the Iowa State Fair. A love of livestock and a passion for science led Dr. Duff major in Animal Sciences. He received his B. S. degree in Animal and Dairy Science from Northwest Missouri State University, M. S. degree in Animal Physiology from the University of Arkansas, and Ph.D. in Animal Nutrition from New Mexico State University.

After finishing his Ph.D., he worked for two years as a Research Specialist at the University of Arkansas, one year as a Sales Nutritionist for Farr Better Feeds in Garden City, Kansas, and seven years at the Clayton Livestock Research Center for New Mexico State University as a postdoctoral Research Associate and Assistant Professor and Superintendent of the station. He accepted his current position with the University of Arizona in 2001 with an 80 percent research:20 percent teaching appointment. During the past 10 years, Dr. Duff has authored or co-authored more than 40 refereed journal articles. He has also served two terms on the Editorial Board for the Journal of Animal Science, on the editorial board for the Professional Animal Scientist and as ad hoc reviewer for several international journals. In addition, I served for three years as Section/Associate Editor for the Journal of Animal Science.

For the graduate experience in the Advanced Nutrition and Management - Feedlot course, graduate students design, conduct, analyze and write a paper suitable for publication in a refereed journal. The first study was published in the Canadian Journal of Animal Science (Bailey et al., 2004; Can J. Anim. Sci. 84:741-743). Another manuscript is currently being prepared for submission in the Journal of Applied Animal Research as a result of a project conducted in the class

Outside of the classroom, Dr. Duff serves on the Department of Animal Science Undergraduate and Graduate Committees and as chair of the College of Agriculture and Life Sciences Curriculum Committee. He also serves on other committees in the department. Besides my involvement in the university, Dr. Duff is also involved in the Tucson community as President Elect of the Rotary Club of Tucson - Sunset and has served as Sergeant at Arms and as director of Club Service. He and his wife Donna reside in Tucson.

Research Interests

Research focuses on nutrition and management factors to improve the health and performance of newly-received beef calves in the feedlot, growing programs for beef cattle, and factors affecting finishing performance and carcass characteristics after harvest.

Receiving cattle: Morbidity in newly-received feedlot cattle continues to be a major concern to producers. It has been suggested that bovine respiratory disease (BRD) is one of the most economically important disease for feedlot cattle. In 1994, the USDA-APHIS reported that 70 pecent of death losses in feedlot cattle can be attributed to respiratory disease. In addition, recent research suggests that cattle that succumb to respiratory disease do not perform as well or grade as well as cattle that has not experienced respiratory disease. Probably as important, is the diagnosis of BRD and the subsequent treatment. Our goals are to evaluate nutrition and management factor to both reduce the incidence and also the recovery from respiratory disease.

Growing programs: One problem facing the industry once the cattle are straightened out is what growing program optimized performance during this period and subsequent performance. The optimum growth during this period under different environmental conditions needs to be examined. Our objectives are to evaluate different growth rates under varying environmental conditions on overall feedlot performance.

Finishing programs: A significant percentage of cattle entering the feedlot are heifers, however, we treat heifer the same as steers with respect to protein requirements, roughage levels, etc. With different implant regimes available, requirements for the various nutrients may exist. Likewise, Holsteins continue to make up a significant number of feedlot cattle in the southwestern United States and nutrient requirements may differ because of the selection criteria for the dairy breeds. New technologies allow evaluation of the effects of nutrition on gene expression. In cooperation with another laboratory in the Department of Animal Sciences, we have the capability to evaluate the effects or nutrition on gene expression in the digestive tract of ruminants. Our objectives for finishing cattle will be to characterize nutrient requirements for both sex and breeds of cattle.

Selected Publications

Duff Lab

Duff Lab
Shantz Building Room 220
Phone; 520-626-3890
Fax: 520-621-9435

Grad Students

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