28 Pork Production 



germ-cells or eggs. This they are able to do by the 

 movement of a tail-like appendage. If the boar is not 

 vigorous, as the result of over-use, or is too fat or in 

 a run-down condition, experiments indicate that the 

 sperms which he produces will themselves lack in vigor 

 and activity. The thing to seek, therefore, is vigorous 

 lively germs, and these can be produced only by a vigorous 

 boar whose services have been regulated carefully. (See 

 page 122.) 



Records. 



The breeder of market hogs does not, as a rule, make 

 a record of the date each sow is bred. When the sows 

 are bred early, however, and the farrowing season is in 

 February or March, a knowledge of the time each sow 

 is due will make possible that preparation and individual 

 attention at farrowing time which are necessary to save 

 the pigs in cold weather. Without a knowledge of the 

 date of service, it will be necessary to depend on careful 

 observation and judgment to indicate when the sows are 

 due. Even with the most careful supervision, the ex- 

 perienced hog raiser makes many bad guesses, and as 

 a consequence a number of the sows farrow with the 

 general herd and imder conditions not favorable to the 

 survival of the pigs. Such experiences suggest that it 

 might be practical for the producer of market hogs, 

 especially when early pigs are attempted, to have his 

 sows tagged and a record made of the time of breeding. 

 In any case, a definite record should be made of the first 

 and last services. 



With pure-bred herds, breeding records are a practical 

 necessity. When more than one boar is in service, as is 

 commonly the case, the record must be depended on in 



