694 Veterinary Medicine. 



a brown scab, under which was very foetid pus, with extensive 

 inflammation. The affection usually occurred on the lower por- 

 tion of the lips of the vulva, in heifers and cows, and in steers 

 around the anus or root of the tail. The scabs which formed 

 seemed to spread very rapidly, destroying more and more of the 

 underlying tissue and forming a thicker and thicker scab. The 

 scab, if pulled off, would expose a raw surface which would 

 bleed very readily. In a short time a new scab would be 

 formed." 



Steddom says : ' 'The vulvar lips thickened and continued to 

 discharge for four or five days. In the meantime certain pus- 

 tules appeared, O.I to 2.5 centimeters in diameter. About the 

 fifth day these ruptured and discharged yellowish pus. ' ' The 

 mucous membranes of the vulva and vagina were dry and 

 slightly congested. The ulcers were covered with brown, leath- 

 ery scabs, which adhered tenaciously and when detached left an 

 angry, red, purulent, granular, elevated and pitted surface. In 

 some of the more severe cases, one or both lips of the vulva had 

 sloughed off, and the sore had extended 10 to 15 centimeters on 

 the skin of the escutcheon. The pus from this sore did not cor- 

 rode the adjacent skin. 



The more severe cases showed loss of appetite, constipation,, 

 hurried breathing, tucking up of the abdomen, with general dull- 

 ness and dejection, and great tenderness of the affected skin with 

 stiff, straddling gait. 



Pathology. This is very obscure. The primary cause of the 

 sores is not evident, though their occurrence on the anus and 

 vulva only, and especially on the latter would suggest an elective 

 affinity of the pciison (microbian or chemical) for these structures- 

 and their products. If we assume a pathogenic microbe (Ba- 

 cillus necrophorus) in the faeces, the question arises as to the 

 cause of the habitual immunity of the steer, and of the margin, 

 of the anus in the majority of the affected heifers. The sus- 

 ceptibility of heifers rather than cows may imply a previous ex- 

 posure and acquired immunity on the part of the mature animal. 



Again if we suspect the existence of a necrobiotic agent of 

 organic origin (like ergotin, secalin, sphacelin) we must assume 

 a superadded microbian infection, implanted in the primary sore 

 and rapidly extending it. The prompt recovery under antiseptic 



