Calf Scours: Prevention and Treatment

Scours is one of the deadliest diseases for cow-calf producers to manage. According to U.S. Department of Agriculture (USDA) data, scours and other digestive problems cause 17.2 percent of non-predatory calf loss in U.S. cattle operations.1 Calf scours is associated with several diseases and characterized by diarrhea, which prevents the absorption of fluids from the intestines. Death from scours usually results from dehydration, acidosis and loss of electrolytes.2

Once an animal has scours it can be time-consuming and spread rapidly so it is often easier to focus on prevention rather than treatment. One option for prevention is to handle cows before their calf arrives. Guardian® is a vaccine from Merck Animal Health labeled for use in pregnant cows and heifers that provides broad-spectrum protection against the leading causes of calf-scours. “Guardian helps ensure that high levels of maternal antibodies are produced by the dam and are then available to the calves through colostrum for protection against scours," says Kevin Hill, D.V.M., Merck Animal Health.

By vaccinating pregnant cows and heifers prior to calving with Guardian it activates the maternal antibodies so each calf doesn’t have to be handled again to get what they need from their mothers’ colostrum. It can take five weeks for cows to respond to vaccinations and transfer antibodies to colostrum so allow ample time for treatment.

If this timeline has passed, producers should look for signs of infectious agents that can lead to scours and then work with their veterinarian proactively to determine options. Frequent causes of neonatal scours include rotavirus, coronavirus, E. coli and Clostridium perfringens. “Coronavirus is far more prevalent than producers realize and therefore the opportunity to actively immunize very young calves at high risk for scours is vitally important,” says Dr. Hill.

At this stage, an additional treatment option could be Bovilis® Coronavirus from Merck Animal Health, an intranasal vaccine that protects against enteric diseases caused by Bovine Coronavirus. The vaccine has shown to demonstrate a 72 percent reduction in scours when given to calves intranasally after colostrum intake on the first day of age.  The results of another study indicate that scours in Bovilis Coronavirus vaccinated calves were reduced by nearly half, and the average duration of clinical signs was reduced to 3.40 days, versus an average of nearly seven days in the control group. 3

Knowing which products to use can be difficult when it comes to scours, and it’s best to tailor vaccination protocols to each herd differently with your veterinarian. “Sometimes you need one product and sometimes you may need both,” says Dr. Hill. “When used as part of a complete vaccination protocol, Bovilis Coronavirus works to produce an active immune response that works with passive colostral antibodies to provide protection against enteric disease in young calves.”

The combination of vaccinating both dams and calves is a huge step forward in best management practices for scours protection. “Consistent vaccination of dams with Guardian and calves with Bovilis Coronavirus can greatly reduce the impact of calf scours in the beef industry and save more calves from the deadliest disease they face in the first month of their life,” says Dr. Hill.
1. “Cattle and Calves Nonpredator Death Loss in the United States,” National Agricultural Statistics Service (NASS) and the Animal and Plant Health Inspection Service, 2010.
2. White, G., D.V.M. & Wohlgemuth, K., D.V.M. (2011, May 4). Calf Scours: Causes, Prevention and Treatment. Retrieved January 24, 2018, from  https://www.drovers.com/article/calf-scours-causes-prevention-and-treatment-0.
3. An Efficacy and Immunogenicity Study Using a Modified Live Intranasal Bovine Coronavirus Vaccine for the Protection of Calves against Enteric Disease Caused by Bovine Coronavirus Challenge (n.d.) Retrieved November 14, 2017, from https://www.merck-animal-health-usa.com/pdfs/cattle/eddicacy_enteric_technical_bulletin_tcm96-210965.pdf