Coccidiosis generally rears its head in calves from about three weeks of age, and is most commonly associated with profuse watery brown/green diarrhoea, frequently containing blood.
It has become a problem on some farms this year with prolonged housing of three- to six-week-old calves. In severe cases, an affected calf can show continuous signs of straining to pass faeces, with a raised tail. These calves can sometimes pass mucus or gut-lining along with faeces.
Once affected, calves can excrete up to a billion oocysts over the course of a full infection, leading to the rapid spread of this highly contagious disease. Infected calves can become stunted in nature, have dry coats and generally never reach their growth potential. There are a number of products on the market to treat coccidiosis, but they are most efficient when used as preventatives in at-risk calves prior to clinical signs.
Calves on farms where coccidiosis has been diagnosed should be strategically treated with coccidiostats at seven to 10 days of age, and again two weeks later where environmental contamination is high. Infected calves showing clinical signs should also be removed from the group as soon as possible, and strict hygiene measures employed in relation to feeding utensils and footwear used.
Proper power washing and disinfection of calf creeps and sheds with an effective disinfectant is also extremely important. Discuss treatment options with your vet.