UC scientists tackle deadly BRD


Sharif Aly

A UC Davis team of veterinarians and other scientists has undertaken a project dedicated to improving the prevention, diagnosis and treatment of bovine respiratory disease (BRD) in dairy calves. The group was awarded $600,000 in September to conduct the project, “Risk assessment, welfare analysis, and Extension education for dairy calf respiratory disease management in California.” 

BRD, also known as pneumonia, is the leading natural cause of death in U.S. beef and dairy cattle. It causes losses of more than one million animals and $700 million every year.

Principal Investigator Sharif Aly, a School of Veterinary Medicine faculty member based in the Veterinary Medicine Teaching and Research Center, states, “Control and prevention of pneumonia are difficult because the disease has multiple causes. Also, the many risk factors interact in complex ways, forming a web that is a challenge to untangle.” Adding to the difficulty is the fact that no standardized method exists to diagnose cases in the field in a timely way. 

Current field diagnosis and treatment decisions are based on mostly subjective clinical criteria that do not adequately predict the underlying pathology. The result is a high proportion of false negative and false positive diagnoses, leading to more severe disease, misuse of antibiotics, loss of production and negative impacts on animal welfare.

Using surveys and interviews focused on a representative sample of California’s herds, Sharif and his co-investigators are collaborating with UCCE dairy farm advisors, Extension specialists and other veterinarians to identify, analyze and validate a set of significant risk factors. Assessment of the housing, nutrition and management of calves and replacement animals in a dairy herd, for example, will help veterinarians develop herd-specific control and prevention programs. Such an approach is used nationwide for Johne’s disease, a disease with production losses and animal welfare concerns similar to those of respiratory disease in cattle. 

This project combines the expertise of key individuals from the School of Veterinary Medicine, the UC Davis College of Agricultural and Environmental Sciences, UC Cooperative Extension and the California Department of Food and Agriculture. In addition to extensive surveys, the program includes training of two veterinarians enrolled in the Graduate Group in Epidemiology doctoral degree and the Master of Preventive Veterinary Medicine program; outreach and continuing education; and immunology-related research. 

The risk assessment project complements genomics work being conducted in an associated USDA grant aimed at identifying DNA-based genetic markers associated with reduced bovine respiratory disease incidence in cattle. (See www.brdcomplex.org/)  

“We hope to provide important gains in preventing, managing, and reducing the severity of one of the most important endemic diseases in dairy cattle,” says Aly. “Reducing the costs of respiratory disease will help California dairy farmers maintain an affordable, safe, and secure milk supply to consumers in California, the U.S. and throughout the world.” 

About ANR Grants

The dairy calf project addresses an Agricultural and Natural Resources strategic initiative for “Sustainable Food Systems” and is one of 16 projects funded by a competitive proposal process. A full list of funded projects, collaborators, award amounts and funding sources is posted at http://ucanr.org/sites/anrstaff/Divisionwide_Programs/2012grants

Project leaders

Sharif Aly, principal investigator, and Alison Van Eenennaam, co-principal investigator, both at Veterinary Medicine Teaching and Research Center, School of Veterinary Medicine; Terry Lehenbauer, co-principal investigator, VMTRC; and Department of Animal Science, College of Agricultural and Environmental Sciences.

Other collaborators include: Randall Anderson, Alejandro Castillo, Carol Collar, Christiana Drake, Jennifer Heguy, Lindsey Hulbert, Betsy Karle, Frank Mitloehner, Nyles Peterson, and Noelia Silva-del-Rio.

• To contact Sharif Aly, e-mail him at saly@ucdavis.edu or for more information, call Communications Officer, Trina Wood, UC Davis School of Veterinary Medicine, (530) 752-5257.