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Show Vaccination for Blacklty. Blackleg ia one of tho most dreaded diseases affecting cattle. Vaccination of the animals hai proved to be the most cll'ectivo preventive treatment yet discovered, and its uso and wht if known ol its valuo woro discmied by Dr. John K. Mohler, of tho United States Bureau of Animal Industry, m r. papor prepared at the request of Secretary Secre-tary F. D. Coburn of tho Kamaa Board of Agriculture and prosentod at the board's recent annual weotlng. . Dr. Mohler said In part: "Blackleg is an infectious disease, caused by u specific germ which la almost al-most universally prosent in the ground In nil districts where tho disease if known to prevail. This Microbe, upon gaining entrance Into tho system, usually us-ually through punctured wounds madr by briars or stubbles, develops rapidly and causes hemorrhagic, bluish-black gas filled swellings. The course of the disease la very rapid, and, the animal usually dies within tweqty-four hours after thu appearance of the flrsV symptom.' .WW. By vaccination we understand the injection into the system of a minute amount of attenuated or artiflciallj weakened blackleg virus for thopurpoee of producing a mild and clinically un-rccognlzablo un-rccognlzablo case of blackleg. Tho virus ia obtained from animals which have-died have-died from blackleg by securing the -affected muscles, catting them into strips and drying thorn In tho air. When per-foctly per-foctly dry thoy aro pulverized, mixed with water to form a paste, smeared In a thin layer on flat dishes, placod in an oven nnd heated for six hours at a tem-poraturo tem-poraturo which approaches that of boiling boil-ing water. Tho paste is heroby transformed trans-formed Into n hard crust, which It-pulverized It-pulverized anl sifted and measurod-oul into packets containing cither ten or twonty-flvo doses. This powder con. stitutes tho vaccine, tho strongth of which is thoroughly tested on experiment experi-ment nniumls before it is distributed nmong the cattle owners. |