176 Veterinary Medicine. 



the ox. Upon the horse the transferred acarus disappears in a 

 few days (Neumann), and on the ox (debilitated), in twenty 

 days (Delafond and Bourguignon). They do not live when 

 placed on any of the other domestic animals, nor on man. 

 Schir6metewsky claims to have found the bovine symbiotes in 

 scabies and alopecia in man, but there is not sufficient evidence 

 to show that the presence of the acarus was more than accidental. 

 Contagion from ox to ox, standing in adjacent stalls is infrequent. 



Symptoms. The lesions are usually confined to the root of 

 the tail, the rump and the parts around the anus and the acarus 

 may confine its ravages to this part for years without material 

 extension. There is loss of hair, and accumulation of scurf, 

 going on to the formation of scabs and cracks in which the para- 

 site can be found in abundance. Itching is comparatively slight, 

 so that abrasions and sores by rubbing are less marked than in 

 other forms of scabies. Extension from the original focus, takes 

 place mainly in foul, ungroomed animals, [and then along the 

 back, chine, and neck, or to the perineum, udder and inner sides of 

 the thighs. Johne has found them on the pasterns without pro- 

 ducing any irritation. In summer the irritation is least and may 

 seem to have entirely disappeared, but only to reappear when 

 housed on the following winter. In animals in poor condition it 

 may contribute to emaciation, and marasmus, but in ordinary 

 cases the health is little affected. 



The diagnosis is to be made by the location and slow advance 

 of the lesions, but especially by the discovery of the symbiotes 

 with its moderately sized rostrum and the long stout nature of the 

 three first pairs of limbs as contrasted with the dwarfed appear- 

 ance of the fourth pair. The presence of lice, easily visible to 

 the naked eye and of the psoroptes, is not unknown, but as the 

 same treatment is applicable to all, the complex infestment is of 

 less account. 



Treatment. Symbiotic scabies in cattle is easily dealt with, 

 any of the applications recommended for sarcoptic scabies in the 

 horse proving effectual. It is all the more satisfactory that the 

 disease is usually circumscribed to a limited area, so that the clip- 

 ping and dressing of the entire skin is unnecessary. Precautions 

 should be taken against infection from stalls and litter, but this is 

 of far less account than in the ca,se of other forms of scabies. 



