The Farmer's Veterinarian: A Practical Treatise on the Diseases of Farm Stock

by Charles William Burkett

BLACKHEAD.

—A germ disease affecting turkeys and chickens. It is characterized by a dark purple appearance in the comb and wattles. Fowls attacked by the disease show dullness and laziness; at the same time indigestion disturbances and diarrhœa is observed. The best treatment is to kill the fowls affected just as soon as they become affected. This will prevent the disease from spreading. It is advisable to burn the bodies of the dead so as to prevent the spreading of the germs. Thorough disinfection is necessary.

BLACKLEG.

—An infectious disease produced by the blackleg bacillus, a parasite which lives and propagates in the soil of infected districts and in the bodies of diseased animals. Certain kinds of soil are very favorable to the existence of the parasite, and such, when once infected, easily remain so permanently and thus constitute the source of the disease. Years ago blackleg was regarded as a form of anthrax. This has been proved erroneous, however, for blackleg and anthrax are two distinct and independent diseases, each being caused by a specific germ. One diseased animal does not transmit the disease directly to a healthy one. When caused, it is the result of self-inoculation, that is, by the germ entering a wound in the skin or mucous membrane of the body, produced on the legs while the animals are roaming over the fields, or at the mouth while grazing; these are the places by which the blackleg germs get into the system.

An animal dying of blackleg is fairly alive with germs, which remain in virulent condition for a long time. It behooves the farmer, therefore, to completely destroy this kind of dead; not by burying, for then the germs remain in the soil. The best way is to burn the animal right on the spot where it died. If the animal is moved to another place, the infection is spread, thereby, and not only the death place, but the grass over which the animal has been moved, should be thoroughly disinfected that no germs may survive. The disease is characterized in the appearance of large swellings on various parts of the body, usually on one of the upper portions of the legs, and never below the hock or knee joints. Swellings vary in size, and are always formed by the presence of gas that has collected in the tissue just beneath the skin. This gas is a product of the germ. You will notice a peculiar crackling sound when you pass your hand over these swellings. When punctured with a knife these swellings emit a bloody fluid possessing a disagreeable and sickening odor.

Associated with the disease are loss of appetite, high fever and lameness. Death follows just a few days from the time of attack. So far no medicinal treatment for cure has been discovered. Stock should not be admitted to infected regions. The only safe practice in regions where blackleg is prevalent is in the use of protective inoculation or vaccination. Such vaccination renders the animals immune, and even if attacked, there is almost no appearance of the disease at all.

Using Blackleg Vaccine.

—The blackleg vaccine now so well known is made from diseased flesh taken from a calf that has died from blackleg. This flesh, after being dried and powdered, is then properly prepared and injected into the animal. There are two kinds—a weak and a strong vaccine and single and double vaccine. The single vaccine requires but one inoculation. The latter is believed to be superior and gives better protection. The vaccine is usually available from the state experiment stations, or can be obtained through your veterinarian. About the only skill required in doing the work is in having the instruments thoroughly cleaned and disinfected. A hypodermic syringe is used and the injection made on the underside of the tail, a few inches from the tip, or just beneath the skin of the neck or shoulder. The point of the syringe should not puncture the muscle at all; simply pick up the skin and draw it away from the muscle and admit the fluid in the loose space between the two.

When vaccinated, the treatment is supposed to last about a year. If calves are vaccinated the operation should be repeated at about the age of yearling. Two periods of vaccination are suggested: when turned to pasture in the spring or when turned to dry food in the fall. Full directions as to the use of vaccines always accompany the preparations and further detail is unnecessary here.

Preventive medicines cannot be relied upon, although a common one is used throughout the West, made as follows: 4 ounces of sulphur, 1 ounce of saltpeter, 2 pounds of sulphate of iron, and 1 pound of air-slaked lime. After being thoroughly pulverized and mixed, this is added to one-third of a gallon of common salt and used in the place of salt.