196 Diseases of the Genital Organs 



The direct influence of certain foods upon fertility has 

 frequently been asserted but is difficult to trace. It is a 

 favorite habit of the breeder and dairyman, when his herd 

 shows a low rate of reproduction, to attribute it directly to 

 food — ensilage, alfalfa, clover, cottonseed meal, and well- 

 nigh every food. Indirectly, foods modify reproduction 

 greatly because the general vigor depends more upon the 

 quantity and quality of food than upon any other one ele- 

 ment. 



D. Idleness and Overfeeding 



Impotence of the male is sometimes expressed chiefly by 

 an absence of sexual desire in the presence of females prop- 

 erly in estrum, without any visible changes of the reproduc- 

 tive organs. Sometimes he may pay attention to the female, 

 with more or less complete erection of the penis, then desist 

 in his attentions, and turn away. When the next female is 

 presented, he may show normal sexual vigor. 



In some cases, there is said to be an individual psychic in- 

 fluence which prevents the male from copulating with a cer- 

 tain female. This is alleged to be especially true of individ- 

 ual stallions, to which certain mares seem to be repulsive, so 

 that they refuse to copulate with them. The presence of 

 young at the side of the dam is sometimes alleged to repress 

 the sexual appetite of the male. This is usually seen, however, 

 only in those males depressed in their vitality. It is almost, 

 if not always, erroneous to attribute absence of sexual de- 

 sire to the caprice or idiosyncracies of the male, by which 

 a female of a certain type or color becomes repulsive to 

 him and fails to arouse his sexual appetite ; the real cause 

 lies in bad management or in disease. 



The tendency to loss of vigor on this account is usually 

 not noticeable in the young, but, as soon as the animal has 

 become mature and grown quite fat, the disposition becomes 

 marked. This form of impotence is seen almost exclusively 

 in those animals which are closely confined, highly fed, and 

 not properly exercised. It is commonest in draft stallions, 

 but is observed in bulls, especially of the beef breeds, and in 

 male breeding animals of all species. It tends to disappear 



