276 VETERINARY HYGIENE 



remain alive outside the body. The mortality is variable, and such 

 deaths as occur are due to septic infection following retention of 

 the placenta. 



PREVENTIVE MEASURES. One attack is said to produce 

 immunity and a second abortion in the same animal is said to be 

 rare. Preventive measures should follow in principle those laid 

 down for bovine abortion. Newly purchased mares should be 

 isolated and separate attendants provided. Should abortion occur 

 in a stud strict isolation and disinfection are essential for the pre- 

 vention of its spread. Aborted mares should not be again used 

 for breeding for at least two months, and then only when treatment 

 by uterine washings has been practised (see Joint-Ill). 



JOINT - ILL. 



Joint-Ill (navel ill) is a pysemic affection of newly-born animals. 

 Infection frequently occurs in foals but also in calves, lambs and 

 pigs. The disease is very widespread both in Europe and on the 

 American Continent, and is probably not confined to any particular 

 breed or strain of animal. Various bacteria have been associated 

 at times by different authors with joint-ill, namely, streptococci, 

 staphylococci, pasteurellae, and colon bacilli. Within recent years 

 however, the confusion which previously existed regarding the 

 etiology of joint-ill has been to a great extent removed by the 

 researches of Polajkow, Dassonville and Riviere, Good and Smith, 

 Schofield, and by M'Fadyean and Edwards* in Great Britain. The 

 latter state that at least a large proportion of cases of equine abortion 

 and some cases of joint-ill occurring in this country are caused by 

 the bacillus dbortivo-equinus previously described by Smith and 

 Kilborne, de Jong, Good and Corbett and others. It is in those 

 cases in which joint-ill in the foal is associated with abortion in the 

 mare that the bacillus abortivo-equinus is the chief offender. 

 M'Fadyean and Edwards succeeded in isolating this organism from 

 foals ; from six of these the bacillus was recovered from the joints, 

 and in three of the latter cases the foal was born dead and free from 

 any sign of joint disease. It therefore appears most probable that 

 in some cases joint-ill is intimately associated as regards its etiology 

 with abortion in mares. Infection would, therefore, be prenatal 

 and of the foals some are born dead, and those which survive are 

 especially liable to suffer from joint affections. In a proportion of 

 cases there is at the same time suppuration at the umbilicus. This 

 may be due to the common pyogenic micrococci, but it is also quite 

 * Journ. Comp. Path., 1917, Vol. XXX., p. 321. 



