.1/./.1/.W77.S' OR MASTITIS. 689 



The structure of the teat and arran^'einent of the inilk- sinuses and 

 ducts in the Mare, Ruminants, and Swine, are, in the opinion of Franck, 

 favourable for the reception of infection ; and this accounts for the 

 readiness with which parenchymatous inflammation of the udder occurs 

 very early in foot-and-mouth disease, the virus of this specific malady 

 finding its way from the surface of the gland into the teat. The wider 

 prevalence of mammitis in close sultry weather during summer, than in 

 cold winter weather, may be accounted for by the readiness with which 

 organic matters putrefy. By the way of infection, those extensive out- 

 breaks of mammitis which occur among flocks of sheep may also 

 be explained. Those cases of the disease which follow abortion, or 

 accompany metritis or vaginitis, may also be attributed to auto-infection, 

 instead of metastasis; indeed, in Franck's view those maladies which 

 lead to the formation of putrid or septic matter — such as parturient 

 fever, omphalitis in the progeny, retention and putrefaction of the after- 

 birth, etc. — may all be productive of mammitis in this way. Disease of 

 the progeny may also give rise to it, the infection being conveyed to the 

 teat by the young in the act of sucking. The hands of milkers or others, 

 or soiled litter or gi'ound on which the animal lies, may also be the 

 means of conveying the infection. Franck believes that the column of 

 milk in the sinuses and ducts is first tainted, and that this is effected 

 through the milk at the end of the teat — a drop or two of which may 

 be suspended therefrom. A chemical change is thereby brought about 

 in the milk, and this altered secretion leads to the inflammation, wliich 

 is secondary. An alteration in the character of the milk is, it will be 

 remembered, one of the first symptoms — if not the first — of mammitis. 

 Consequently, "dry"' Cows, or those to which the infection cannot 

 obtain access, are not attacked by the malady ; and " dry " Cows 

 suffering from foot-and-mouth disease never have parenchymatous 

 mammitis. 



In 1SS4, Nocard bad an opportunity of confirming Franck's views 

 while investigating an enzooty of mammitis that had prevailed among a 

 number of Cows for six years. In milk from the affected udders, he 

 constantlj' found a special micro-organism which could be readily culti- 

 vated in milk and other fluids ; when the twelfth culture of this germ 

 was injected into the teat of a Cow or Goat the milk become acid and 

 clotted, and the tissue of the gland after a time was denser than in 

 health. This injection had no effect on the Bitch. 



what consistt^nt, slightly f)r not at bII sensitive, .ind dark or blftck in \\\\v. Tlie line oi 

 demarcation between the healthy and diseaoed portion in perfectly defined ; the former 

 being of a ro'v colotir, and normal in nizn and consistency. The diseased condition 

 spread.** l>eyond the tidder to beneath the alnlonien, and when an ulcer apfiears on the 

 ^land. di<chart;ini,' a f<itid sanguinolent fluid, the animal then becomes depressed and 

 le\eri^h, debility and emaciation set in, and the cr'ature succumbs to an attack rif 

 septika'mia. 



The numerous necroscopical examinations made by Kivulta confinn, in his opinion, the 

 distinction he has establi."he<l lH;tween this special malady and erysipelatous mammitis. 

 With reijard to the causeo, the shepherds affirm that the malady attacks those sheep 

 which are kept for a long time "n a thick bed of litter ; others, again, .i.Hsert that it 

 appears when they .tre allowed to pasture in the oj>en air, and are not confined. The 

 same uncertainty prevail- with regard to its contagiousne«s. The shej>herds carefully 

 isolate the affecte<l animals : and it would seem that, by their doing so, the disease is 

 limited to those first attacked. 



Rivelta is of opinion that this form of mammitis is produced and maintained by 

 special micrococci and bacteria, which penetrate by the teats, or at some part of the skin 

 covering the gland. 



44 



