The general treatment of contagious mammitis does not differ from that of the simple form, except that antiseptics should be given by the mouth as well as applied locally (hyposulphite of soda, one-half ounce daily).
COWPOX.
This is another form of contagious inflammation of the udder which does not spread readily from animal to animal except by the hands of the milker. It is held to occur spontaneously in the cow, but this is altogether improbable, and so-called spontaneous cases are rather to be looked on as instances in which the germs have been preserved dry in the buildings or introduced in some unknown manner. It is not uncommon in the horse, attacking the heels, the lips, or some other inoculated part of the body, and is then easily transferred to the cow, if the same man grooms and dresses the horse and milks the cow. It may also appear in the cow by infection, more or less direct, from a person who has been successfully vaccinated. Many believe that it is only a form of the smallpox of man modified by passing through the system of cow or horse. It is, however, unreasonable to suppose that this alleged modified smallpox could have been transmitted from child to child (the most susceptible of the human race) for 90 years, under all possible conditions, without once reverting to its original type of smallpox. Chauveau's experiments on both cattle and horses with the virus of smallpox and its inoculation back on the human subject go far to show that in the climate of western Europe, at least, no such transformation takes place. Smallpox remains smallpox and cowpox, cowpox. Again, smallpox is communicable to a person who visits the patient in his room but avoids touching him, while cowpox is never thus transferred through the air unless deliberately diffused in the form of spray.
The disease in the cow is ushered in by a slight fever, which, however, is usually overlooked, and the first sign is tenderness of the teats. Examined, these may be redder and hotter than normal, and at the end of two days there appear little nodules, like small peas, of a pale-red color, and increasing so that by the seventh day they may measure three-fourths of an inch to 1 inch in diameter. The yield of milk diminishes, and when heated it coagulates slightly. From the seventh to the tenth day the eruption forms into a blister, with raised margins and a depression in the center, and from which the whole of the liquid can not be drawn by a single puncture. The blister, in other words, is chambered, and each chamber must be opened to evacuate the whole of the contents. If the pock forms on a surface where there is thick hair it does not rise as a blister, but oozes out a straw-colored fluid which concretes on the hairs in an amber-colored mass. In one or two days after the pock is full it becomes yellow from contained pus and then dries into a brownish-yellow scab, which finally falls, leaving one or more distinct pits in the skin. Upon the teats, however, this regular course is rarely seen; the vesicles are burst by the hands of the milker as soon as liquid is formed, and as they continue to suffer at each milking they form raw, angry sores, scabbing more or less at intervals, but are slow to undergo healing.
The only treatment required is to heal the sores. As milking is the main cause of their persistence, that must be done as gently as possible, or even with the teat tube or dilator. ([Pl. XXIV], figs. 3 and 4.) It is essential to check the propagation of the germ, and for this purpose the sore teats may be washed frequently with a solution of half an ounce hyposulphite of soda in a pint of water. This will usually check the inflammation and cut short the malady.
SUPPRESSION OF MILK.
The absence of milk in the udder may result from ill health, debility, emaciation, chronic disease of the bag, wasting of the gland from previous disease, or insufficient feed, but sometimes it will occur suddenly without any appreciable cause. The treatment consists in removing the cause of the disease, giving rich albuminoid feed made into warm mashes, and administering ounce doses of aromatic carminatives, like anise seed, fennel seed, etc. Rubbing and stripping the udder are useful; the application of oil of lavender or of turpentine, or even a blister of Spanish flies, will sometimes succeed.
BLOODY MILK.
Blood may escape with the milk when the udder has been injured by blows; also when it is congested or inflamed, when the circulation through it has been suddenly increased by richer and more abundant feed, or when the cow is under the excitement of heat. The milk frothing up and assuming a pink tinge is often the first sign of red water, and it may result from eating acrid or irritant plants, like the Ranunculaceæ, resinous plants, etc. Deposits of tubercle or tumors in the udder, or induration of the gland, may be efficient causes, the irritation caused by milking contributing to draw the blood. Finally, there may be a reddish tinge or sediment when madder or logwood has been eaten.
In milk which becomes red after it is drawn it may be from the presence in it of the Bacillus prodigiosus. This also grows on bread, and is the explanation of the supposed miracle of the "bleeding host."