Elliot T. Stevens1, MS, DVM; Daniel U. Thomson1*, PhD, DVM; Christopher D. Reinhardt2, PhD; Nels Lindberg3, DVM
1Department of Clinical Sciences, Kansas State University, Manhattan, KS 66506
2Department of Animal Science and Industry, Kansas State University, Manhattan, KS 66506
3Animal Medical Center, Great Bend, KS 67530
*Corresponding author: Dr. Dan Thomson, College of Veterinary Medicine, 1800 Denison Avenue, Manhattan, KS 66506, Email: email@example.com, Phone: 785-532-4254
Twelve lots of auction-derived steers totaling 1,577 head with an unknown health history (initial body weight 660 lb [300 kg]) were used to investigate testing and removal of feeder calves persistently infected with bovine viral diarrhea virus (PI-BVDV) upon arrival at a single feedlot in central Kansas. Pens with a PI-BVDV calf present at arrival were considered exposed and were compared to pens of steers that arrived without a PIBVDV calf in the group. Both exposed and non-exposed pens of steers were followed from arrival through harvest to investigate the impact of exposure on health, performance, and carcass characteristics of feedlot cattle. A significant difference in the morbidity between exposed (2.3%) and non-exposed (7.2%) cattle was found (P<0.01). No differences in retreatment or mortality rates were found between groups. Exposure to a PI-BVDV animal for less than 48 hours after arrival did not have an effect on performance parameters. There was an increased percentage of USDA yield grade 4 and 5 (P=0.01) carcasses in the exposed cattle, but no other differences in carcass characteristics were found between groups.
Keywords: bovine, BVDV, persistently infected, PI, feedlot
Stevens ET, Thomson DU, Reinhardt CD, Lindberg N: Bov Pract 43:117-121, 2009.