INFECTIVE DISEASES OF COW 211 



udder are caused by bacteria, which may set up diseased conditions 

 in the bodies of persons consuming the milk. The specific organ- 

 ism of mastitis is a diplococcus or streptococcus, and it may be 

 readily found in the milk of animals whose udders are so affected. 

 The causal bacteria gain access to the interior of the udder, in all 

 probability, by way of the milk duct in the teat, and the disease 

 may therefore be conveyed from one cow to another by the 

 hands of the milker. The relationship between mastitis and 

 disease in persons drinking the milk, is at present obscure. Many 

 abnormal conditions, including some epidemic infective diseases 

 and outbreaks of sore throat, have been attributed to mastitis in 

 the cows supplying the incriminated milk. But little is known of 

 the exact conditions set up.^ Streptococci are frequently found 

 in milk derived from presumably healthy udders, and in such 

 cases have apparently gained access from the air, or as a result 

 of unclean handling or manipulation. Under certain circumstances, 

 these organisms set up marked changes in the milk containing 

 them. 



The organisms, setting up enteritis in the milch cow, may be 

 responsible for setting up diarrhoea in man. In any case there is 

 evidence of the capacity which milk has, under certain circum- 

 stances, of causing gastric and intestinal disturbance in persons 

 consuming it. 



Foot-and-mouth Disease in milch cows is occasionally accom- 

 panied by vesicles on the udder, especially at the opening of the 

 milk duct. This condition often leads to sores and crusts being 

 formed, preventing the ready flow of milk, and leading to a marked 

 pollution therein. The infection of the disease may be con- 

 veyed for long distances by persons and things which have come 

 into contact with the diseased animals. Dr Thome was one of 

 the first to investigate some apparent cases of transmission of the 

 disease to man by means of infected milk.- He concluded " that 

 a disease appears sometimes to have been produced in the human 

 subject when the milk of cows suffering from Foot-and-mouth 

 Disease has been freely used without being boiled. There is no 

 evidence to show whether this affection is of a specific nature or 

 not." But Dr Thorne had to acknowledge " that in a very large 



* Jour, of Comp. Path., vol. xv., p. 163. Report of Roy. Vet. Coll., 1903, pp. 

 19-21. 



2 Report of Medical Officer of the Privy Council, 1869, p. 294. See also 

 record of outbreak affecting fourteen persons reported by Siegel, Jour, of State 

 Med., 1898, p. 178. 



