Coccidiosis: A Variable That Can be Managed on Arrival

Fall is a transition time in the cattle business. Unfortunately, transition equals stress for calves, which can result in increased incidence of disease. Dr. Nels Lindberg, AnimalMedicalCenter, Great Bend, Kan., says coccidiosis is one disease producers should pay extra attention to as calves enter the feeder or stocker phase.

"We try to focus on variables we can manage," he says. "We cannot control if calves were preconditioned or how long they spent on the truck, but one thing we can help prevent is coccidiosis."

Dr. Lindberg explains that coccidiosis is commonly seen in beef calves. In fact, it is so common that it can affect calves from all environments and geographies,1 and the prevalence of infection can be up to 100%.2

"Coccidiosis is a stress-induced disease," Dr. Lindberg says. "During the fall, calves are separated from their mothers, shipped and have to adjust to a new diet all of which can be stressful, and a trigger for coccidiosis."

For this reason, Dr. Lindberg recommends that his clients help calves fight coccidiosis as part of their receiving routines.

"With coccidiosis, it is important that we knock out the parasite quickly to help avoid the costly effects of the disease," he says. "That is why I recommend that calves are given a coccidiostat on arrival, especially in starter yards or yards receiving high-risk or light-weight calves."

Dr. Lindberg adds that most coccidiosis cases are subclinical, which adds another level of urgency to helping calves fight the disease. Research has shown that 95% of all cases are subclinical and are never diagnosed.3 If visible signs do occur, it is not until three to eight weeks after the initial infection. By then, much of the damage has already been done.1 Coccidia destroy the lining of the small intestine, which results in incomplete absorption of nutrients and electrolytes.3 The result is dehydration and reduced feed efficiency. One study showed a 30% reduction in feed efficiency in animals that were infected with coccidia.3

"A calf's job during the stocker or early feeding phase is to stay healthy and gain efficiently," says Dr. Joe Dedrickson, associate director, Merial Veterinary Services. "Coccidiosis can make both of those things next to impossible resulting in decreased productivity that the calf may not be able to make up."

Dr. Dedrickson adds that the good news is CORID® (amprolium) can be used as an aid in the prevention and treatment of coccidiosis, and it is available in multiple formulations.

"CORID is a convenient option for all producers because it can easily be mixed with any type of drinking system or used as a drench," Dr. Dedrickson says. "The in-feed formulation also provides a convenient, user-friendly option as producers can mix it in with the ration or provide it as a top-dress."

Producers should consult their veterinarian and follow label instructions. For coccidiosis prevention, Dr. Dedrickson recommends producers use CORID at the prevention dose rate (5 mg/kg) for 21 consecutive days. If clinical signs of coccidiosis do occur, cattle should be treated with CORID daily for five consecutive days at the treatment dose rate (10 mg/kg) according to the label.

For another level of flexibility, CORID can be used in calves in USDA Natural and NE3 programs.4,5

"Cattle can't fight coccidiosis on their own, so it is important for producers with all types of operations to help cattle defend against this costly disease by using CORID as part of their regular receiving routine," Dr. Dedrickson says.

Dr. Lindberg says the costly effects of coccidiosis and the high incidence of the disease make it one producers should focus on as calves enter the feeding phase.

"When we look at the big picture, coccidiosis can cause malabsorption of nutrients, losses in performance and efficiency and an overall increase of health costs," he says. "If we can use a product that will help prevent coccidiosis, it more than pays to do so."

In addition to Natural and NE3 programs, CORID is an optional protocol for the MERIAL® SUREHEALTH® Calf Preconditioning Program. For more information, visit or call 1-888-MERIAL-1.

CORID (amprolium): Withdraw 24 hours before slaughter. Do not use in calves to be processed for veal.

1Kvasnicka, B. Coccidiosis in beef cattle. Cattle Producer's Library CL685. University of Nevada Extension Beef Cattle Resource Committee. 2003;223(12):1738.
2Daugschies A, Najdrowski M. Eimeriosis in cattle: current understanding. J Vet Med B 2005;52:417-427.
3Quigley J. Calf Note #17 A review of coccidiosis in calves. Available at: Accessed May 15, 2009.
4Federal Register. Rules and regulations. 2008;73(197):59479–59482.
5Data on file at Merial.