378 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



occupy space in this work except by a reference to the serious 

 disease which is produced by this variety of mite through certain 

 characteristics natural to it. We find Sarcoptic mange in the follow- 

 ing domesticated animals: Horse, sheep, goat, dog, cat, and pig. 



This variety dig galleries under the outer layer of the skin and 

 live on the cells of the middle layer of the skin. They multiply in 

 these galleries and occasion a very intense inflammation of the skin. 

 Because of the depth to which the Sarcoptes burrow Sarcoptic mange 

 is exceedingly hard to eradicate. It would, therefore, seem fortu- 

 nate that this form of the disease is not common to cattle. It is 

 rebellious to all medication, and very frequently recurrences of the 

 disease are seen after treatment which has been prolonged for months. 



Transmissibility of Mange. Concerning the transmissibility of 

 the different manges to animals and man, we find that all Sarcoptes 

 may live for a considerable period upon man's skin, but the common 

 mange mites, the first variety described, and the tail-mange mites, 

 the second variety described, die very rapidly and occasion but slight 

 irritations. The horse may contract Sarcoptic mange of the sheep, 

 pig, dog, and cat. The ox takes the Sarcoptes of the horse, sheep, 

 goat, and cat. The sheep contracts Sarcoptic mange of the goat. 

 The dog takes the Sarcoptes of man, pig, cat, sheep, and goat. The 

 pig contracts Sarcoptic mange of the goat. From this it will be 

 seen that Sarcoptic mange, unlike the common and tail manges, 

 is transmissible from one species of animal to another. 



Mange is never developed except by contagion. The period of 

 incubation that is, the interval that elapses between the moment 

 when the mites are deposited upon the surface of the body and the 

 appearance of the disease on the skin varies according to the num- 

 ber of mites transmitted. When in small numbers, the first mani- 

 festations of mange are sometimes seen as late as four to six weeks, 

 while at other times the disease may be clearly apparent at the end 

 of 15 days. Contamination takes place either by direct contact 

 that is, immediate, as on pasture, at the stable, etc. or by inter- 

 mediary agents. 



Disinfection. What has already been said with regard to the 

 contagious character of scabies in cattle of the number of scab mites 

 which may be found in a small quantity of the debris of the skin and 

 their ability to live and remain active for a considerable length of 

 time under unfavorable conditions will indicate the importance 

 of the thorough disinfection of corrals, sheds, or other buildings in 

 which affected cattle may have been kept. It is therefore necessary, 

 in order to attain success in the treatment of this disease, to destroy 

 parasites which have fallen off or have been dislodged from the ani- 

 mals, as well as those that are upon them ; otherwise there is danger 

 of their becoming reinfected from the premises after the effects of 

 the remedy applied to the animals have disappeared. 



Treatment. Methods in operation for the treatment of scabies 

 in sheep have become more or less familiar to all people interested 

 in sheep husbandry, and it may be said that the same treatment so 



