The owner of a small hobby farm in the Tweed on the far north coast of NSW notified the Emergency Animal Diseases Hotline.
The owner reported hair loss around the eyes and ears in a 17 month old Damara x Dorper ewe. Two in-contact lambs were not affected. Four Boer goat kids, six month of age and introduced four weeks previously, were reported to have lesions around the ears and head. They were in poor condition and two died about two weeks after arrival, with what the owner suspected to be Haemonchosis. The three in-contact adult Boer goats had no signs. The owner drenched the sheep and goats with Q drench two weeks previously and the two remaining kids responded in condition.
The owner had a rash develop on the lower legs two days after drenching the sheep and goats. This consisted of multiple raised nodules about 2mm in diameter which were mildly pruritic. The itchiness settled after treatment with antihistamine cream and at the time of notification the nodules had developed a scab and were in the process of healing.
On examination the ewe had bilateral periorbital alopecia, giving the sheep a spectacled appearance. There was also hair loss at the base of the external pinna and thickening and proliferative appearance to the inner pinna, with a dark greasy exudate (Figure 1). The appearance of the ears was very similar to ear mite infection in cats. The two goat kids had a scaly dandruff appearance to the external pinna. The lesions on the owner were near resolution.
Twenty-four hours after examining the stock the examining veterinarian developed multiple, mildly pruritic raised nodules 1-2mm diameter on the palmar aspect of the left wrist (Figure 2). The nature and appearance were characteristic of human Sarcoptes infection. The lesions were self limiting, did not spread and resolved within 3 weeks.
Sarcoptes mite infection was suspected in the ewe and mild Dermatophilus infection in the kids.
Skin scraping from the external pinna of one goat kid: Gram stain examination for Dermatophilus was positive and Dermatophilus congolensis was isolated on culture. No organisms were seen and culture was negative on the periorbital and internal pinna skin scraping from the ewe.
Dermatophilus congolensis in the goat kids. Suspect Sarcoptes infection in the ewe, the owner and the author; diagnosed on epidemiologic observation, clinical signs and treatment response.
The owner was recommended to treat the ewe 3 times with Ivermectin, at 7 day intervals. The ewe responded well to the recommended treatment. The mild Dermatophilus lesions in the goat kids were seen as self limiting and no recommendations made, other than to seek advice if the lesions progressed. Despite wet weather in the weeks that followed, the lesions resolved without treatment. Given the possibility of a zoonosis protective clothing and gloves were recommended when handling the stock.
Given that the case had been reported to the EAD Hotline and that there appeared to be possible human health implications, NSW DPI requested a response to this notification.
Dermatophilus is common in young sheep, goats and cattle, particularly during wet humid summers on the NSW North Coast. The majority of cases in calves are self limiting, however some calves can progress to an extensive debilitating condition with death due to fluid and protein loss. The author has sampled several of these individuals and found these to be Pestivirus virus positive 'Persistently Infected' calves.
This is the author's first experience with a suspected case of Sarcoptic Mange in sheep.