MILK AND TUBERCULOSIS.

Otago Witness, Issue 3031, 17 April 1912, Page 20

MILK AND TUBERCULOSIS.

HOW PIGS ARE AFFECTED. The cause of tuberculosis In pigs would appear to bo associated with the use of milk from affected cows. Investigations made in .parts of China where milk of any kind is never fed to pigs, have revealed' almost absolute immunity from the disease. An American paper recently stated that tuberculosis seems to be gaining ground in ite ravages among pigs throughout the country. United States Federal inspections show_ that approximately 2 per cent, of the animals slaughtered were affected, and of these 10 per cent, wore eo badly diseased that they were of no value except as a fertiliser. Many farmers who have sold diseased pigs have done so without suspecting that the animals were unsound, because few pigs manifested tine presence of this scourge by outward symptoms when they left the farm. In some instances tho pig that discloses the disease after shipment is frequently the finest-looking animal in the herd. Where indications of tuberculosis are evident they usually consist of general unthriftincss, and such symptoms, of course, accompany other diseases, and, therefore, do not afford definite signs of tuberculosis. —Surprise and Disappointment.— In the majority of oases no sign of the disease will bo given until the animal is slaughtered, and a discovery of tuberculous pigs in a drove of prime, well-finished individuals is often the cause of great surprise and disappointment. Yet the lesions may be so great as to render the meat unfit for food. It is evident that the suppression of this trouble would mean a saving of thousands of pounds annually to the country. The question involved is how pigs become infected with germs which cause the disease. Best authorities say that return products from creameries, such as raw or hand-separated milk from tuberculous cows, feeding after diseased cattle and tuberculous oaroases, are great distributors. The first two causes are very similar. The second is moro easily controlled, and usually affects only a single farm, which does not injure neighbouring stock. Of course, the return products from a creamery might be sold and the milk from one farm affect any

number of herds. Serious results of feeding milk from diseased cows are realised when 83 per cent, of a herd fed on tuberculous milk for three days have contracted the disease. Other pigs fed l for 30 days upon mdlk from tuberculous cows were all diseased. Feeding behind tuberculous cows is more or less local in nature but is far more important than generally thought, since many feeders keep a number of hogs in the yards. In herds where cattle are not infested this is commended because of its economy. The United States Federal Government reports a case of 34 pigs marketed by farmers, 23 of which were diseased. In this instance the pigs were not fed on any milk nor allowed to mingle'with the cattle, but worked the manure over, which was the cause of the infection. —A Serious Question. — Large numbers are not likely to be diseased by eating tuberculous carcases, but when pigs are kept around the slaughterhouse there is considerable danger. Tnis is a serious question when it is known that the pigs are kept for food. Since pigs invariably contract tuberoulosis through eating infected material, the best means of eradication are in using pure feeds, free from tuberculous matter. . This means that we must avoid feeding milk that is returned from the creamery without the assurance that it contains no germs. Pigs must not be allowed to follow cattle, unless it is known that these animals are disease free. The tuberculin test has made it possible to eliminate diseased animals, and when individuals have been discarded it is neoessary to observe pigs as closely as cattle. A tuberculous mother may transmit this disease to her offspring through the milk. The U.S.A. Bureau of Animal Industry pointed out a case where practically every pig from one farm was diseased, and upon further examination found that all the poultry was infected. The chickens that died were fed to the pigs, which thereby contracted the disease. Keports from inspectors show that the disease is rapidly decreasing in localities where strenuous efforts have been made to fight it. Means for eradication are thoroughly outlined, and much better understood now than formerly.— Weekly Times.