The prevalence and pathogenicity of Chorioptes bovis (Hering, 1845) and Psoroptes cuniculi (Delafond, 1859) (Acari: Psoroptidae) infestations in feral goats in New Zealand.

Between October 1976 and January 1980 a total of 368 feral goats was examined in New Zealand for the presence of Chorioptes bovis and 434 for the presence of Psoroptes cuniculi. The seasonal pattern of C. bovis infestation in feral goats was similar to that seen in sheep and cattle. The prevalence of infestation reached 100% in July and August (winter) and declined to 27% in February and March (summer). Fewer goats were infested with P. cuniculi and prevalence of infestation reached a maximum of 41% in July. No goats were found infested in the December and January samples. Chorioptes bovis infestation was independent of the age and sex of hosts. Infestation with P. cuniculi was independent of the sex of the hosts, but older goats were more frequently infested (16%) than younger goats (8.6%). Unilateral infestation with P. cuniculi was more common (74.5%) than bilateral infestation. No severe lesions were associated with C. bovis, but 21.3% of goats with P. cuniculi had the external auditory meatus blocked by waxy material and 12.8% had scabby encrustations on the ears. The importance of goats as a possible source of infestation to domestic animals is discussed.