THE HORSE AS A PRODUCER OF ANTITOXINES. 
393 
fluid substrate charged with the toxine. The whole process is 
by no means simple, but calls for tedious work, painstaking 
accuracy and patience, and in spite of all of this may bring 
disappointments and unexpected difficulties, which must be 
overcome before further steps can be taken and success 
attained. 
Having thus prepared the toxins, the animal for inocula¬ 
tion is selected, and it has been found that the horse is prefer¬ 
able to any other animal. He is most susceptible to these 
toxins, most tractable in the almost painless operation of 
remittent injections; he yields the largest amount of blood 
serum from one bleeding, aud most of all produces a thera¬ 
peutic serum of the strongest immunizing value. The horses 
selected at our college for this purpose are healthy, strong 
and large animals of good disposition, between the ages of 
six and eight years, and they make a favorable impression 
upon those timid visitors who yet entertain doubts as to the 
value of serum therapeutics. 
What interests us most, as veterinarians, is the effect which 
the injections of the different toxins have upon the organism 
of the horse. There are certain symptoms, such as the rise 
of temperature, which are common to all toxins; otherwise, 
however, they are so widely different that it is well to give a 
separate description of each. 
The inoculation with diphtheria-toxine has been lately de¬ 
scribed by Dr. Gill, of New York, and I shall, therefore, only 
briefly mention our own method. As the best places for in¬ 
jection we select the thorax and flanks, the proximity to the 
extremities being avoided on account of subsequent oedema- 
tous swellings. A piece of skin of the size of a dollar is 
shaved, washed and disinfected with a solution of bichloride 
of mercury. The toxin is then drawn into a sterilized syringe 
of the capacity of 10-50 cc. and slowly injected subcutaneously. 
We commence with a small injection of 2 cc. of a weak toxin, 
and gradually increase during several weeks to 50 cc. 
The effect of diphtheria-toxine upon the system of the horse 
is mainly a rise in temperature of to 3 degrees, a quickened 
circulation and accelerated respiration, but not in a very pro- 
