366 Agricultural Journal of Victoria. 



evaporation during the processing, water at 200^ is to be occasionally 

 added. By means of a hypodermic syringe, a teaspoonful, when 

 cooled, of the vaccine thus prepared should be injected beneath the 

 skin behind the shoulder, into each beast, as a preventive of the 

 disorder. A more efficient and permanent vaccine can be prepared 

 by taking pieces of muscle from the swelling and drying them by 

 exposing them to the wind in the sun. This process, however, takes 

 some time to get the vaccine prepared ; but by this means a vaccine 

 can always be kept on hand. When the pieces of muscle are dried 

 they are finely ground, and the powder is then subjected to a 

 temperature of 200" Fah. for six hours. The powder is again 

 pulverised as finely as possible, and if kept dry will keep a year or 

 more. The dried powder contains the spores of the germ of blackleg 

 which have been attenuated in virulence by the treatment. The 

 injection of the attenuated virus confers a lasting immunity on an 

 animal over six months of age. The dose is about 1-2 grains of 

 the powder. The powder is mixed up with a teaspoonful of water, 

 and injected beneath the skin. To remove sediment the solution 

 should be filtered through a little cotton-wool before use, so as not 

 to clog the hypodermic needle. 



Tetanus. 



Tetanus is a disease common to man, and certain of the higher 

 animals. Outbreaks of tetanus or locked-jaw in lambs and sheep 

 occasionally occur, and in cases that have come under notice some 

 considerable number have been affected. At the starting point of 

 infection the^e is usually redenia. The cause of the disease is a 

 bacillus, the spores of which reside in the earth. Under the 

 microscope the bacillus may appear as a slender elongated rod, or it 

 may have a drum-stick appearance. In the case of animals con- 

 tracting the disease spontaneously it is found only in the tissue 

 around the wound of entrance. It does not pass into the general 

 system. It acts upon the animal solely through the medium of the 

 soluble poison which it manufactures. The germ does not grow in 

 the presence of oxygen, and it liquefies gelatine. It gains entry into 

 sheep through wounds inflicted during shearing, castration, and other 

 operations. In some cases, indeed, there may be no visible channel 

 of entrance. The presence of a wound, however small, is essential 

 for the virus to gain entrance. The disease generally begins with 

 involuntary spasmodic motions of the head and lockjaw. The jaws 

 may be so tightly locked that they cannot be separated. The head 

 may be drawn backwards through the contraction of certain groups 

 of muscles, or from the contraction of other sets of muscles other 

 peculiar attitudes may be observed. This stiffness may relax, and 

 generalised muscular spasms may come on, followed again by stiffness. 

 Death may occur pretty rapidly, and the post-mortem examination 

 may reveal no appearances of any importance except at seat of 

 infection. On the intiiction of a wound during shearing or other 

 operation, the part should be washed with a strong solution of 

 permanganate of potash, and then covered with Stockholm tar. 



