Influence of Disease. 



of lower specific gravity, but richer in albumin (Jensen). The 

 injection of the contagion of pox into the ducts of the udder results 

 in the development of pox vesicles on the walls of the milk ducts. 

 After 2 to 3 days a swelling of the udder, with increased sensitive- 

 ness, develops and the secretion is changed. It becomes purulent 

 and bloody on the eighth to the tenth day (Lienaux and Hebrant). 

 Transmission from animal to animal may be brought about 

 by milking, and the entire herd in a stable may rapidly become af- 

 fected. The course of cow pox is usually benign. According to 

 Herz the milk becomes rich in cells, contains colostral bodies, and 

 it has an unpleasant taste. Careful examination showed the fol- 

 lowing results : 



Beginning of After 13 After 40 



observations days days 



Specific gravity of the milk 1 . 0265 1 . 0270 1 . 0215 



Specific gravity of the whey 1 . 0245 1 . 0235 1 . 0209 



Acidity according to Soxhlet-Henkel . 5.3 6.6 4.1 



Fat 5.36% 4.02% 5.54% 



Solids 13.31 11.82 12.25 



Fat-free solids 7.95 8.81 6.72 



Ash 0.72 0.72 0.8 



Transmission of pox from cattle to man is of course very 

 readily possible, and is not at all uncommon as a result of milking 

 affected animals. After the ingestion of infected raw milk the pox 

 exanthema may develop on the face (Jensen). 



The so-called false or gangrenous variola which may be fre- 

 quently observed on the teats of fine-skinned, fresh milking animals 

 should not be mistaken for true pox. These eruptions are pro- 

 duced by the ordinary pus-producing organisms, which have been 

 rubbed into the skin during milking or have penetrated the skin 

 by means of various injuries. Small furuncles and skin abscesses 

 result, which heal without influencing the formation or secretion 

 of the milk. Healing is of course retarded through the act of milk- 

 ing, and during the presence of the pus cells, blood and pyogenic 

 organisms may pass into the milk in small quantities. These false 

 pox lesions are not very important. 



Of much greater importance than cow pox is foot-and-mouth 

 disease which sometimes appears extensively. This is a highly 

 acute febrile disease which is transmitted to cloven-footed animals 

 with remarkable ease. The most striking symptom which occurs 

 in association with the disease, the vesicular eruptions, may also 

 affect the udder, and especially the teats. 



The udder swells, becomes painful, and red-bordered vesicles 

 develop in sizes up to that of a walnut, which burst during milking 

 or spontaneously, leaving painful ulcers. During the beginning 

 of foot-and-mouth disease the yield of milk is considerably dimin- 

 ished, sometimes one-quarter less than the usual yield, as a result 



