Calf scours is one of the most important and costly calf health issues affecting dairy operations in North America. According to the USDA, scours, diarrhea and other digestive problems are responsible for more than half of all pre-weaned heifer calf deaths.
The National Animal Health Monitoring Survey attributes six in 10 deaths of calves under the age of 2 months to calf scours.
Financial losses are not measured solely by calf mortality; veterinary care, medications and increased labor to treat sick dairy calves are also costly. More importantly, scours impairs growth and reduces performance and overall profitability throughout the lifetime of the animal.
Calves that scour in the first 14 days of life are at a higher risk for mortality due to secondary infection during the first 90 days of life. According to Iowa State University, the normal cost of raising a heifer varies from $1,661.50 to an excess of $2,200 from weaning to calving. Those numbers are compounded when a calf scours, especially since it’s 2.5 times more likely to be culled earlier than its healthy counterparts.
Calf scours is caused by any number of micro-organisms. They range from viruses such as rotavirus or coronavirus to bacteria such as E. coli, salmonella or protozoa such as cryptosporidia. Scours can also be incited by nutritional challenges like changing dietary inputs, unpasteurized waste milk, transport and vaccinations.
Climatic factors such as wet environments, freezing temperatures and wind chill make calves particularly susceptible.
Whatever the cause, scours severely dehydrates newborn calves, whose bodyweight is around 70 percent water. Calves can lose 5 to 10 percent of their bodyweight in water within a single day of scouring. More than 14 percent loss of water can cause death. Unfortunately, once a calf starts scouring, replacing lost fluids is not enough.
An effective oral rehydration program must provide sufficient amounts of fluids, offer an effective solution for correcting acid-base balance and provide nutrition.
