1 42 Veterinary Obstetrics 



vigorous exercise, which will, as a rule, though not always, re- 

 store the sexual powers. 



In a general way, the food of a breeding male needs be rich in 

 protein, as compared with the amount of hydrocarbons and car- 

 bohydrates. The most common foods, when well grown and 

 cured, are the best for the breeding animal, such as bright, aro-. 

 matic hay and clean, well developed oats, along with grass, to 

 which may be added, in the winter, roots and tubers. Rarely, 

 if ever, is it necessary or even advisable or permissible to add to 

 the food any .sexual stimulant like pepper or mustard. 



3. Excessive Sexual Use. The number of services which 

 a male animal can effectively render is an important question for 

 the breeder. It probably varies greatly with different indi- 

 viduals. Naturally, the power of a male does not rest so much 

 upon the number of females which he is expected to serve as 

 upon the number of copulations essential to cause fertilization. 

 It has been determined by careful investigation that, when the 

 number of copulations during a given day is increased, the 

 abundance of spermatozoa in the semen rapidly decreases and, 

 if this service is pushed too far, the spermatozoa fail almost en- 

 tirely, causing an interruption of the fertility of the animal. 

 Much will depend upon the age and vigor of the male animal. 

 Zschokke states that 80 to 100 cows may be bred to a single bull 

 when the animal is kept confined and his service somewhat regu- 

 lated by the breeder but, if allowed to con.sort with the cows at 

 pasture, not more than 50 should be allowed. In the western 

 range country of America, the allowance is very much smaller 

 and it is considered safer that there be one bull to each 20 or 25 

 cows. This is necessitated largely by the fact that, during the 

 principal breeding season, the bulls have not yet fully recovered 

 their vigor from the long and trying winter with scant food sup- 

 ply. Zschokke further holds that the bull should not be allowed 

 to serve more than three cows in any one day and that, under 

 such conditions, there should be one or two days per week of 

 complete rest. 



In the stallion, similar rules as to numbers and conditions are 

 applicable. The total number of females, however, may be 

 greatly increased over that suggested by Zschokke, if the service 

 is distributed throughout the year, and noted stallions have been 

 known to serve successfully, and without apparent injury, two 



