Symptoms of Contagious Ecthyma in Sheep

New Zealand Journal of Agriculture, Volume 87, Issue 1, 15 July 1953, Page 15

Symptoms of Contagious Ecthyma in Sheep

By

R. M. SALISBURY,

Chief Diagnostic

Officer, Department of Agriculture Animal Research Station, Wallaceville \- " v - . THE disease contagious ecthyma is perhaps better known as "scabby mouth", but as the scabs are by no means confined to the mouth, the term may be misleading. Recently some outbreaks of contagious ecthyma have been reported in which the main features have been scabs on the feet. The symptoms of the disease are described in this article to enable sheep farmers to recognise it in its various forms. CONTAGIOUS ecthyma is a virus v-/ disease which is confined to sheep and goats, though odd cases have been recorded in men, mainly sheep farmers, shepherds, etc., who have developed pustular lesions on the hands as a result of handling infected sheep. The disease is most commonly seen in lambs, though older sheep are equally susceptible. Lambs are principally affected because older animals are usually immune, either as a result of vaccination as lambs or because they have acquired a natural infection at an early age. The main features of the disease are the development of little pustules on

the lips which eventually coalesce into a thick, hard scab which prevents the affected animals from suckling properly, the result being that the lamb loses condition rapidly. A similar type' of scab may develop just above the feet and may extend as high as the knees and hocks. This year there have been a number of outbreaks where the scabs were mainlv confined to the legs, with a small percentage of cases showing scabs on the mouth also. A few sheep which were kept under observation made a good recovery without treatment in

about 14 days, but another when first examined was badly fly blown around the feet. Cracking of the skin at the coronet had produced an ideal spot for the fly to strike. Where lambs are affected and the ewes on which they are running are susceptible the disease will be transferred to the udder of the ewe. Some very serious complications have arisen as a result of udder infection, because

gangrenous mastitis, is a common sequel. \ Contagious ecthyma may therefore be manifested in many ways, but it is usual to expect a percentage of cases with the scabs on the mouth. Rams have been seen where the infection has extended to the scrotum. .These features are pointed out so that the disease may be \ recognised whether it is found on the lips, legs, scrotum, udder, or on : any other portion of the body. It is usually confined to the unwoolled parts and those most susceptible to injury from thistles, etc., through which the virus is allowed to enter. \ Scabby mouth is a disease which can be readily controlled by preventive vaccination. The method was described in the “Journal of Agriculture” for July 1950, though the Animal Research Station, Wallaceville, no longer provides vaccine as it did at that time. However, the vaccine is readily available at small cost and those requiring it should inquire from . their local veterinary surgeon or Livestock Instructor. If a property is known to be infected, and ewes are brought in, it would be a wise precaution to vaccinate these ewes before lambing; otherwise they may pick up the disease from the lambs later, with the disastrous results mentioned earlier. The virus is very hardy and will live for several years under ordinary conditions of temperature, etc. It may be assumed therefore that once a property has had infected sheep on it it is infected for all time and the only safe method of control is by vaccination. At the same time it would be unwise to vaccinate lambs unless the disease had been diagnosed on the property.