Sterility 195 
Spermatozoa are present, they will be observed as 
small swimming tadpole-like organisms. Should the 
spermatozoa be absent, or should the fresh speci- 
mens be inactive, the trouble is clearly located in the 
spermatic fluid, which is formed in the testicle. It 
is very rare for males ever to recover their fertility 
if the spermatozoa are not found in the spermatic 
fluid. Sometimes, however, this absence is due to 
some temporary disorder, which can be removed. 
Abnormal growths and diseases of the genital system 
in the male must be dealt with according to cireum- 
stances. In such cases it is frequently an economical 
plan to castrate the animal and fatten him for the 
market. 
Sterility in the female may be due to an absence, 
or to an abnormal condition, of the ovum, or egg, 
which develops in the ovary and is discharged into 
the uterus or womb periodically at the time of “heat.” 
These conditions are not frequent, however, as those 
animals which come in heat regularly and with the 
normal symptoms are usually fertile, so far as the 
egg is concerned. It is difficult to determine when 
sterility is due to an absence, or to sterility, of the 
egg-cell. 
Another cause of sterility in the female is an altered 
secretion of the mucous membrane which lines the 
genital organs. If this secretion be acid in reaction, 
it is fatal to the male cells, or spermatozoa. The 
mucous membrane may be diseased, and this condition 
may cause sterility. In some animals, especially cows, 
there is often observed a disease, known as nymphomania, 
