A Definition of Calf Scours

Calf scours is not a specific disease but a broad description that covers any disease or condition causing diarrhea in a calf. Scours can be caused by bacteria, viruses, parasites or bad or moldy food. When a calf is having scours it loses body fluids, electrolytes and body condition rapidly. The digestive tract also gets damaged causing stomach cramps, abdominal pain and gas. It is important to get a veterinarian to determine the cause of scours and treat it immediately, and to feed the calf electrolytes to prevent dehydration, the leading cause of death from scours.

  1. Symptoms

    • The symptoms of scours are diarrhea -- watery stools. No matter what causes the scours, the calf's body reacts by trying to flush it out. A good farmer or livestock owner will keep a regular check on his calves and notice any changes immediately. The greatest danger with scours is that the calf loses an enormous amount of water from its body. Essential electrolytes -- potassium, sodium and chloride -- exit the body in the water, which impairs the calf's ability to function. The scouring calf's body does not absorb any nutrients, and the calf weakens rapidly.

    Non-infectious Scours

    • Like all young creatures, the digestive system of a calf is immature and weak. It reacts to sudden changes in feed. If a calf has been feeding on one particular type of feed that is changed totally in one day, the calf's digestive system may not be able to adapt to the change immediately, causing scours. Any change in diet should be made gradually to prevent scours. Moldy hay can also cause scours, and the feed should be checked at the first sign.

    Infectious Bacterial Scours

    • Certain strains of bacteria may contaminate a calf's feeding area, causing scours. These bacteria produce toxins that invade the calf's intestinal lining, causing irritation. These may include the enteric, enteroxigenic, or septicemic types of e-coli bacteria. They attack a calf in the first 14 days of its life. Salmonella and clostridium perfringens are more serious and affect the calf's organs as well as causing scours, and death often occurs rapidly. All of these are easily transmitted to other calves, and affected calves must be isolated immediately and the pen disinfected.

    Infectious Viral Scours

    • Rotavirus and coronavirus are the most common viruses that may be associated with calf scours. They cause scours in calves 10 to 14 days old by attacking the intestinal lining and multiplying. This causes the calf to weaken and become more susceptible to bacterial infections. Bovine Viral Diarrhea (BVD) can also cause scours, but most calves are protected by their mothers' colostrum, the milk she produces at birth, because older cows are vaccinated against the disease.

    Parasites

    • Coccidia, cryptosporidia and guardia -- protozoal micro-organisms -- enter the calf's body through contaminated water or feed and live in the intestine. Coccidia's life cycle is 21 days, so the calf usually gets scours at 18 to19 days after birth, while cryptosporidia can infest the calf seven to 21 days after birth.