Sarcoptes scabiei var ovis is rare in sheep and is reportable in the USA. It affects the nonwooly skin, usually starting on the head and face. In goats, S scabiei var caprae is responsible for a generalized skin condition characterized by marked hyperkeratosis. Lesions start usually on the head and neck. In both species, the injectable formulations of ivermectin, doramectin, or moxidectin at 200 μg/kg are efficient treatments.
Chorioptes bovis is common in Europe, New Zealand, and Australia during the winter. It has been eradicated in sheep in the USA and is a reportable disease. The distribution of lesions is the same as that in cattle. C caprae is fairly common in goats. Papules and crusts are seen on the feet and legs. If necessary, the animals can be treated using sprays or dips containing organophosphates (diazinon, metrifonate, propetamphos) or pyrethroids (deltamethrin, flumethrin) as permitted.
Psoroptic Mange (Sheep Scab)
Psor-optes ovis infestation is a reportable disease. No cases have been reported in the USA since 1970, but sheep scab is still present in many countries, including some in western Europe. Large, scaly, crusted lesions develop almost exclusively on woolly parts of the body. Intense pruritus manifests by biting and scratching. Left untreated, sheep often become emaciated and anemic. Mites are sometimes found in the ears. Ivermectin and moxidectin (200 μg/kg) given twice with a 7- or 10-day interval, respectively, are effective. Doramectin (300 μg/kg) given once is also effective. Dipping is most effective if done within 2 wk after shearing and must be repeated after 14 days. Approved treatments for mange in sheep are 0.3% coumaphos, 0.15–0.25% phosmet, 0.03–0.1% diazinon, and 2% hot lime-sulfur. Outside the USA, other sprays or dips such as propetamphos, phoxim, amitraz, or flumethrin are available.
Psoroptic mange (ear mange) in goats, caused by Psoroptes cuniculi, usually affects the ears but can spread to the head, neck, and body and cause severe irritation. This occurs particularly in Angora goats, in which the mohair is considerably damaged. The disease in Angora goats is reportable in Texas. Although the course is chronic, the prognosis is good. Any of the acaricides approved for use in sheep will eliminate P cuniculi in goats. Lactating dairy goats should be treated only with lime-sulfur solution.
This has been reported in sheep (Demodex ovis) and goats (D caprae), in which it causes lesions similar to those in cattle. In goats, nonpruritic papules and nodules develop, especially over the face, neck, shoulders, and sides. The nodules contain a thick, waxy, grayish material that can be easily expressed; mites can be found in this exudate. The disease can become chronic. Localized lesions in goats can be incised, expressed, and infused with Lugol's iodine or rotenone in alcohol (1:3). For generalized cases in goats, treatments include ronnel in propylene glycol (180 mL of 33% ronnel in 1 L of propylene glycol) applied to one-third of the body daily until cured, and rotenone in alcohol (1:3) applied to one-fourth of the body daily. Trichlorfon (2%) has been reported to be effective for demodicosis in sheep.
Psorergatic Mange (Itch Mite, Australian Itch)
Psorergates ovis is a common skin mite of sheep in many parts of the world; it has been eradicated in the USA and is a reportable disease. The disease is characterized by intense generalized pruritus and scaliness, with matting and loss of wool. Because of their small size, the mites are difficult to find in skin scrapings. This disease can cause significant economic losses through weight loss and wool damage. Dipping or spraying with 2–3% lime-sulfur, 0.2% malathion, or 0.3% coumaphos is effective in controlling the disease; 2 treatments with a 14-day interval are needed. Ivermectin and other avermectins/milbemycins given SC have been reported to be curative.
Last full review/revision July 2011 by Bertrand J. Losson, DVM, PhD, DEVPC; Bernard Mignon, DVM, PhD, DEVPC