Location: Livestock Issues Research
Project Number: 3096-32000-008-08-T
Project Type: Trust Fund Cooperative Agreement
Start Date: May 1, 2015
End Date: Apr 30, 2020
The specific objective of this experiment is to determine if supplementing the diet of newly received beef calves with a yeast product will mitigate the negative impact of a controlled bovine respiratory disease challenge and improve beef cattle health and performance.
The scope of work is similar to the scope of work in the existing agreement in that ARS scientists will be responsible for conducting intensive blood sample collections from cattle from indwelling jugular catheters. Additionally, ARS scientists will be responsible for conducting a bovine respiratory disease challenge on 32 head of feedlot heifers. Heifers will be transported to the USDA-ARS Livestock Issues Research Unit’s Bovine Immunology Research and Development Complex and then all calves will be weighed, fitted with an indwelling temperature recording device, and then challenged intra-nasally with approximately 1 x 108/mL plaque forming units of bovine herpesvirus-1. Three days later, all calves will be challenged intra-tracheally with 50 mL of 1 x 106 colony-forming units of Mannheimia haemolytica /mL. Blood samples will be collected at 0, 1, 2, 3, 4, 5, 6, 7, 8, 12, 24, 36, 48, 60 and 72 hours post-bacterial challenge via the indwelling jugular catheter.