Mange in alpacas, llamas and goats in the UK: incidence and risk

A retrospective postal questionnaire was used to obtain information about the prevalence of mange and its association with husbandry-related risk factors, in alpaca, llama and goat herds in the UK. In total 1797 questionnaires were sent out to members of the British Alpaca Society, the British Llama Society and the British Goat Society, giving response rates of 40.4%, 29.3% and 22.8% from the three groups, respectively. Between January and December 2007, mange was reported in 52.2% (151 of 292), 14% (9 of 66) and 21% (41 of 194) alpaca, llama and goat herds, respectively. However, these figures must be treated with some caution as only 37-51% of the farmers had their diagnosis of mange confirmed by a veterinarian or animal health laboratory. In herds where the causal agent was confirmed: psoroptic, sarcoptic, chorioptic and mixed infections were all reported, with chorioptic mange reported most frequently. Risk analysis showed that the prevalence of reported cases mange in alpacas was significantly associated with herd size and the country from which the animals were imported. Alpaca farmers who had larger herds were more likely to report mange and farmers who imported their animals from Peru were 1.5 times more likely to report mange than farmers who imported animals from elsewhere or who did not import. There was no significant confounding between these two risk factors. The results show that mange continues to be a major problem for camelids and goats in the UK, and suggests that inadequate control on farms and lack of control when in quarantine are two factors that contribute to ongoing problems with mange. However, given the relatively low contribution of imported animals to the national herd each year, it is likely that poor on-farm control may be of greatest importance.