Cattle ectoparasites in Great Britain

Ectoparasites are almost ubiquitous on British cattle, reflecting the success of these parasites at retaining a residual population in the national herd.

Lice infestation is common and may be associated with significant disease especially in young moribund calves. The chewing louse Bovicola bovis is a particular challenge to eradicate given its limited response to various therapies and emerging evidence of reduced susceptibility to pyrethroids.

Chorioptes is the most common cause of mange in cattle and given its surface feeding habits can be difficult to eradicate with current treatments.

Psoroptic mange has re-emerged in British cattle in recent years and while the prevalence of infestation is low this parasite poses a significant challenge for treatment especially in dairy cattle. Scabies is rare in British cattle but, like psoroptic mange, can cause significant pruritus and skin disease. Furthermore it is a potential zoonosis.

Diagnosis of such ectoparasites is usually made by interpretation of signs of skin disease; definitive diagnosis requires microscopic examination of the ectoparasite which can more accurately inform the implementation of control measures.

In the future, control measures for such ectoparasites may need to move away from the reliance on synthetic pyrethroids and macrocyclic lactones, to consider alternative topical agents.