Project Number: 3625-32000-106-00
Project Type: Appropriated

Start Date: Oct 01, 2011
End Date: Sep 30, 2016

Objective:
Objective 1: Determine the impact of variant and emerging viruses on the development and control of respiratory disease in ruminants. Develop means to detect and survey for variant viruses and develop models for evaluating infections with emerging variant viruses. Subobjectives: (1a) Determine impact of variant and emerging viruses; (1b) Improve current surveillance methods and diagnostic tools used to detect and control emerging viruses. Objective 2: Elucidate the host-pathogen interactions associated with the Bovine Respiratory Disease Complex (BRDC) by defining host pathways modulated as a result of viral infections and characterizing the role of stress and immunological related host effector molecules in BRDC. Subobjectives: (2a) Define interactions of viral pathogens that may contribute to the development of respiratory disease; (2b) Define modulation of host immune response to viral infection associated with stress caused by vitamin D insufficiency. Objective 3: Evaluate formulations and delivery systems for vaccination of neonates by identifying means to modulate stress and immunological factors associated with BRDC. Generate identification criteria and means to generate “vaccine ready” calves to develop intervention strategies for controlling viral respiratory infections of ruminants. Subobjectives: (3a) Identify factors, associated with common management practices, that modulate immune function in neonatal calves; (3b) Evaluate candidate vaccine for use in calves.

Approach:
The goal of this project is to reduce the incidence and impact of viral infections in ruminants with particular emphasis on viral infections that contribute to respiratory disease in cattle. The project encompasses three distinct but interrelated research efforts. The first is to determine the incidence and impact of variant viruses, such as subgenotypes of bovine viral diarrhea virus (BVDV), and emerging viruses, such as HoBi-like viruses, to bovine respiratory disease. The purpose of this research is to determine if new antigens, representing variant and emerging viruses, need to be included in vaccines. The second is to examine the interaction of host and virus in respiratory disease. Included in this effort will be the study of host immune dysfunction, resulting from viral infection, nutrition, or stress. The purpose of this research is to define factors that contribute to respiratory disease in order to develop means of intervention that negate or ameliorate those factors. The third is to determine means by which host resistance to viral infection can be enhanced with emphasis on improving protective innate and acquired immune responses in calves. The information generated from these three research areas will be used in the development of intervention strategies to control and eliminate viral pathogens. Improved control of viral pathogens will benefit consumers by ensuring a healthful food supply, enhance animal health and well-being, and reduce production costs for farmers and ranchers.