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Coccidiosis Is a Controllable Disease

Dairy Pipeline: June 1998

Tom L. Bailey
Dairy Production Medicine
Virginia-Maryland Regional College of Veterinary Medicine
Virginia Tech
(540) 231-3936; email:

Coccidiosis is a controllable disease that affects calves from as early as 10 days of age to calving. This disease causing diarrhea and dehydration is completely preventable with good management and strategic medication. However, your local veterinarian should diagnosis scours of any type with a good history, examination and laboratory test. The most common signs of coccidia are watery scours with flakes of blood, dull listless calves, mucus in the feces, dehydration and weight loss. These signs are usually coupled with a recent stress such as moving or regrouping calves, severe weather changes, feed changes, or with impending parturition. Several coccidiostats (delays the development of the coccidia during the life cycle) are available as a feed additive. These would include Deccox®, Rumensin®, and Bovatec®. It is very important for producers to understand however, that each works at a different stage of the life cycle within the calf. Rumensin and Bovatec also have the added advantage of increasing feed efficiency and controlling coccidiosis. Adequate control should be initiated as early as 5 to 7 days of age when calves begin to consume calf starter. Problems may arise when coccidiostats are switched, since they work at different stages of the life cycle, allowing development of the arrested coccidia. Blending feeds that contain different coccidiostats may not give adequate controlling levels of either coccidiostat, leading to a break in coccidiosis control. Make sure adequate levels of one coccidiostat are supplied to the calf. It is also important to realize that once coccidiosis is clinical or causing a disease problem, these products will not rid the calf of the infection. This is where a coccidiocide is to be used. Some veterinarians may choose to use a sulfa drug or a drench or feed additive such as amprolium, (Corid®). If calves are too sick to eat, the drench is a more effective means of medication. Extremely ill calves may also need to be treated with fluids and other supportive therapy. Once the disease is under control the calves are then placed on a preventative as previously mentioned. Sanitation plays a major role in prevention. Always keep calf hutches, pens, and pastures, clean, dry, and comfortable. Thoroughly clean and disinfect hutches between calves. Isolate calves with coccidiosis or other scouring problems to prevent spread of any disease. Clean and disinfect your boots and wash your hands after treatment of sick calves. Keep feed off the ground and in a bunk to avoid possible oral ingestion of coccidia. Remember to contact your veterinarian with any scour problems and attain a positive diagnosis.

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