Emily Payne explains the causes, symptoms and treatment of coccidiosis in lambs.
Causes of Coccidiosis in Lambs
Coccidiosis is a commonly seen, serious issue in lambs. It is caused by a single-celled protozoan parasite that affects growth rates, causes scouring and, at worst, can lead to death.
The cycle initially starts with the ewes shedding oocysts in their muck. As the muck builds up in housed environments, the lambs ingest more and more oocysts. The ewes themselves have a degree of immunity, but the younger lambs are susceptible.
Signs of Coccidiosis in Lambs
The oocysts are very resilient and can build up on pasture, creating a problem after lambs have been turned out. Once lambs start suffering with coccidiosis there will be an initial drop in the growth rate, followed by scour and, if left untreated, gut damage and eventual death.
Often there can be subclinical disease present and diminished growth rates are not noticed until clinical disease develops. Lambs typically are at the highest risk when one to three months old. If this coincides with the risk period for nematodirus (variable each year, but often in May), mixed coccidia and nematodirus infections can occur, resulting in very severe disease.
Treatment of Coccidiosis
Coccidia oocysts are easily identified by carrying out a faecal egg count. Once identified, a treatment and prevention plan can be put in place.
As a faecal-oral disease, one of the major factors in controlling coccidiosis is hygiene. In sheds, this means mucking out and disinfecting with a coccidia-approved disinfectant; outdoors this means rotating grazing, moving feed troughs and minimising poaching to avoid the ingestion of large numbers of oocytes.
There are multiple oral drenches available once a diagnosis has been made, or in more severe cases in-feed preparations can be prescribed from your vet.