DISEASES FOLLOWING PAETURITION. 237 



of the bag, and from that it may extend to the others as it does from 

 cow to cow through the milker's hands. 



Another form almost universally prevalent in this district of cen- 

 tral New York in 18S9 broke out on the teats and udders as blisters 

 strongly resembling coAvpox, but which were not pi'opagated when 

 inoculated on calves. It was only exceptionally that this extended 

 through the teat to the gland tissue, yet in some instances the bag 

 Avas lost from this cause. Scarlatina in man was very prevalent at 

 the time (many schools were closed in consequence), but no definite 

 connection seemed to exist between this and the cow disease, and on 

 different dairy farms there were families of young children that had 

 never had scarlet fever and who did not at that time contract it. 



The most common cause of contagious mammitis in cattle is a 

 spherical bacterium in chain form (Sfreptococcus) (Moore, Ward). 

 Yet it is clear that contagious mammitis is not a single affection, but 

 a group of diseases which have this in common, that they attack the 

 udder. 



Prevention. — Prevention is to be especially sought in all such cases. 

 In purchasing new cows see that they come from a herd where the 

 teats and udder are sound. If a new cow with unknown antecedents 

 comes from a public market, let her be milked for a week by a person 

 who does not milk any other cows. Keep her in a separate stall from 

 others, so that there may be no infection from litter or flooring. 

 Wash the udder with soap and water, and wet with a solution of two 

 teaspoonfuls of carbolic acid in a pint of water before letting the 

 regular milker of the other cows take her. If any cow in the herd 

 shows the indurated end of the teat or the inflammation and nodular 

 tender character of the gland, sequestrate her at once and give her a 

 separate milker. If another cow is to be put into the stall she occu- 

 pied, first clean and scrape it, and wet it with a strong solution of 

 bluestone, 5 ounces in a gallon of water. The milk maj' be drawn off 

 with a teat tube, or spring teat dilator (PL XXIV, figs. 3 and 4) , and 

 the milk ducts injected frequently with a solution of peroxid of 

 hydrogen or iodoform. I have had little success in checking the up- 

 ward progress of the disease through the teat with carbolic acid or 

 boric-acid solutions. Used on the outside of the other teats, how- 

 ever, they may serve to prevent them from becoming infected. In the 

 absence of peroxid of hydrogen the affected teat may be injected 

 with a solution of 1 grain corrosive sublimate in a pint of water, 

 and the same may be used on the other teats, provided it is washed 

 off every time before milking. 



As additional precautions, no cow with a retained afterbirth or 

 unhealthy discharge from the womb should be left with the other 

 cows. Such cows doubtless infect their own udders and those of the 



