Coccidiosis in lambs – an update

• Coccidiosis caused by a single celled parasite, Eimeria, is most often seen in young lambs from 4-8 weeks of age that have been exposed to a high level of oocyst challenge

• Clinical signs include weight loss; profuse diarrhoea containing mucus and often flecks of blood; staining of the perineum and tail; straining; abdominal pain; a tucked-up stance; dehydration and death if left untreated

• High levels of infection most often occur in intensive husbandry systems where there are high stocking densities and/or lambs under stress
– Can be a problem for lambs born and reared indoors as well as grass reared lambs

• Coccidia (Eimeria) are highly host specific so infection can only originate from other lambs and sheep

• Prevention of infection is dependent on good hygiene and husbandry so keep pens and feeding troughs clean and dry

• An adequate intake of colostrum will assist the lamb in coping with coccidial and other infections

• If possible avoid grazing mixed age groups of lambs on the same pasture and on fields which have carried ewes and lambs within the previous 2-3 weeks

• Diagnosis of coccidiosis should be based on farm history, clinical signs, faecal  analysis and, where animals have died, from a post-mortem examination of the gut

• As many species of coccidia do not cause disease, total oocyst counts may not always provide a good indicator of the cause of scouring – ask for the oocysts to be  identified (speciated)

• Since a range of pathogens can cause scouring in young lambs, e.g. Nematodirus, it is vital to obtain a diagnosis from your vet

• Oral and “in feed” treatments are available for the control and prevention of coccidiosis

• Oral anticoccidial treatment should be administered as soon as a positive diagnosis has been confirmed

• Lambs with severe scouring due to coccidiosis may also require supportive rehydration therapy