Feeding and Handling the Herd 27 



or two months. It is safer, however, not to force him 

 to the limit of his powers. As already stated, it is usually 

 better not to use the pig until he is a year old. If well 

 developed, however, he may be allowed two or three 

 services a week when eight months of age. If used to 

 excess when young, the effect is seriously to retard develop- 

 ment and to injure the future breeding powers. 



Some boars are naturally more vigorous than others 

 and can settle twice the number of sows in a breeding 

 season. Boars from prolific mothers are believed to be 

 more fertile than those selected from sows which do not 

 produce large litters. The way the boar has been fed, 

 the amount of exercise he has had during the season when 

 he was not in service, the sanitary conditions under 

 which he has been kept, have a great influence on his 

 performance during the breeding season. For these 

 reasons, good judgment is the only reliable guide in 

 determining the extent to which the boar can be used 

 with safety. 



A careful distribution of the services is important. 

 Nothing is gained by allowing the boar two services when 

 the sow is bred. If the first service is a good one, millions 

 of male germ-cells, called sperms, will be present to 

 fertilize the female germ-cells, or eggs, of the sow. Since 

 one sperm only is required to fertilize each egg, it is 

 obvious that the practice of giving the sow a double 

 service is not only unnecessary, but a waste of the energies 

 of the boar. An important fact to remember at this point 

 is that the successful union of the male and female germ- 

 cells depends to a large extent on the vigor and activity 

 of the male cells. It is usually necessary for these male 

 germ-cells to travel a considerable distance in the uterus 

 and Fallopian tubes of the sow before reaching the female 



