The whole life cycle of Sarcoptes occurs on the host, although transmission can occur through life cycle stages that survive for short periods (probably days) in the environment. The primary clinical sign of sarcoptic mange in cattle and sheep is intense pruritus, which may interfere with meat and ilk production, and there may also be scaliness and hair loss, as well as damage to the skin resulting from attempts to relieve the itching.
Order: Astigmata (Sarcoptiformes)
As well as the Order Astigmata, the Subclass Acari consists of the Order Ixodidae containing the hard (Family Ixodidae) and soft (Family Argasidae) ticks, and several other Orders (Mesostigmata, Prostigmata and Orbatidae) containing the parasitic and free-living mites. Other members of the Order Astigmata of importance in veterinary medicine include Chorioptes, Otodectes and Psoroptes.
In Canada, Sarcoptes mites and sarcoptic mange are found on dogs and free-ranging canids, on pigs, very rarely on cattle, and on people. Sarcoptes on other susceptible domestic animal hosts, for example horses, sheep and goats, are probably very rare in Canada or do not occur. It is uncertain whether the mites on these different hosts are members of a single species.
Host range and geographic distribution
Life cycle - direct
Life Cycle: Sarcoptes species
Sarcoptes mites spread easily among their hosts by direct contact and also, to a lesser extent, by fomites. In cattle these would include fencing, scratching posts and perhaps bedding. The mites probably cannot survive off the host for more than a few days.
On a global basis, the incidence and severity of human sarcoptic mange seems to follow an approximately ten year cycle, possibly because of the waxing and waning of an infestation-induced "herd immunity". The existence of such a cyclical pattern of disease in domestic animal hosts is less certain.
Pathology and clinical signs
Treatment and control
There are several products approved in Canada for treatment of sarcoptic mange in cattle: injectable and topical (pour-on) doramectin (DECTOMAX), and ivermectin (VARIOUS) and topical moxidectin (CYDECTIN) and eprinomectin (EPRINEX). Some of these products have milk withdrawal and slaughter delay requirements.
Additional information on the products mentioned is available from the Compendium of Veterinary Products (Twelfth Edition, 2011), or from the manufacturers.
For control of sacoptic mange in cattle it is very important to isolate infested animals, and to treat all cattle at risk.