Coccidiosis is a widespread and economically significant disease of livestock caused by protozoan parasites of the genus Eimeria. This disease is worldwide in occurrence and costs the animal agricultural industry many millions of dollars to control.

Coccidiosis is a disease caused by a protozoan parasite called Eimeria spp or Isospora spp that affects mostly young animals. This parasite is widespread and a huge risk to livestock and their farmers. If the animals get sick, it can cause severe dehydration and sometimes death.

Diseases such as Coccidiosis can greatly affect your cattle’s health, growth rates, milk production, and profit margins, so it’s essential to be aware of these diseases, the causes, symptoms, and how to go about preventing and treating them.

What is Coccidiosis?

Coccidiosis is an acute invasion and destruction of cells inside the intestines of animals by parasites called Eimeria spp or Isospora spp. Eimeria species, when present in sufficient numbers, cause severe enteritis and necrosis of the gut and invade the intestinal mucosa or epithelial cells. There are many different genera and species that can infect a wide variety of mammals, birds, reptiles, and fish. Typically, Eimeria or Isospora parasites are host specific and cannot infect species other than their target species.

These parasites are widespread and only some animals will get sick with Coccidiosis. Farm animals are most likely to get sick if they consume a large number of these parasites. Animals such as cattle or sheep can internalise the parasites through eating infected pasture and feed, drinking contaminated water, or by grooming themselves.

To find out more read this technical bulletin from AgriHealth NZ

What is Coccidiosis in Cattle?

In cattle, coccidiosis may produce clinical symptoms in animals from 3 weeks to a year old, but it can infect all age groups. Coccidia has the ability to multiply rapidly and cause clinical disease.

The disease tends to occur when animals consume large numbers of parasites. They are at higher risk if they are exposed to stress, such as overcrowding or poor weather conditions. The disease can present as mild or severe, and severe cases can lead to death.

Coccidiosis usually takes between 16 and 30 days from when the animals get infected for them to start showing symptoms. The worst of it usually lasts 5 to 7 days from the onset of symptoms and, if the animal is lucky enough to survive, recovery usually starts after those 7 days.

A full recovery from the disease can take weeks due to the damage that has been done to the animal’s intestines. Cattle will likely lose a lot of weight and subsequently lose a lot of their needed daily nutrition.

What are the Symptoms of Coccidiosis in Cattle?

If your animals get sick with Coccidiosis, the first noticeable clinical signs are likely to be diarrhoea that may contain mucus or blood or the animal may have difficulty passing faeces. The animals may have a decreased appetite and mild depression on top of this.

In more severe infections, this may progress to severe depression, dehydration, pale mucous membranes, straining and severe weight loss. Some cattle with coccidiosis may present with neurologic symptoms and in extreme cases, they can die from the disease. For more info please refer to DairyNZ

How Does Coccidiosis Occur?

Coccidiosis is a parasitic disease that infects the intestinal tract when animals consume large numbers of the parasites. If an animal is infected with the parasites, they pass the eggs in their faeces. The disease can spread from one animal to another by contact with infected faeces or ingestion of infected tissue.

The life cycle of the coccidia eggs can survive up to 2 years in moist conditions, so the infection can be passed on from one season to the next in the soil of the pastures or in the barns. It can be killed, however, by drying or using high temperatures. Steam cleaning or drying out barns and feeding equipment will eliminate the build-up of eggs and help to reduce infection.

What is the Best Treatment for Coccidiosis?

Coccidiosis is a self-limiting disease, and recovery without treatment is possible when the multiplication stage of the parasite has passed. The most popular treatment for coccidiosis is Amprolium, an antibiotic that blocks the parasite’s ability to uptake and multiply. Amprolium is commonly added to the animal’s water supply, however, in some cases, where sick animals aren’t eating or drinking enough, the medication is given orally or as an injectable. Another form of treatment is with Baycox, a coccidiostat to treat parasitic diseases. In virtually all cases, Eimeria spp is implicated when this method is effective.

Management and Prevention

Good hygiene, management, and cleanliness are integral for the prevention of Coccidiosis. Investing in indoor farming practices enables farmers and their teams to monitor health issues and feed intake. Disinfecting buildings and feeding equipment by steam cleaning, water blasting, and spraying with a product that kills coccidia eggs is common practice. As coccidia can survive outdoors in warm and moist conditions, it’s good practice to divide the farm into separate areas for different generation groups. Occasionally, each section can be depopulated, cleaned, and sanitized.

Farms can also prevent the parasites from infecting their livestock by adding coccidiostats to their feed. These drugs slow the growth of coccidia but need to be administered correctly to be effective.

If you experience an outbreak of coccidiosis, isolate the affected calves separately from those with no symptoms, although treatment should be given to all cattle in the group even with no clinical signs as they have been exposed and likely infected by the parasite. Move all your calves to an uncontaminated area where stressful procedures are minimised to prevent outbreaks in more animals.

Calves that survive this disease may have experienced extreme weight loss and may struggle to maintain a healthy growth rate. It’s recommended to administer preferential feeding to those affected to bring growth rates back to normal.