360 Pork ProdvxAion 



The figures in the above tables afPord an opportunity 

 of comparing the cost of the finished market pig under 

 four general systems of production. In making this 

 comparison with the idea of determining the most profit- 

 able system to follow, however, several important con- 

 siderations should be made. The first is that the gilt 

 does not produce nor raise, on the average, as large litters 

 as the mature sow. The number of pigs farrowed 

 normally increases up to and including the fourth litter 

 (see Fig. 8, page 99). A second important fact is 

 the impossibility of having as early pigs when gilts are 

 exclusively depended on as when more mature sows are 

 used. This means a later and usually a lower market for 

 pigs farrowed by gilts. More important in the long run, 

 probably, is the difficulty of improving, or even of main- 

 taining, a high average of breeding performance when 

 gilts only are employed. The exclusive use of gilts for 

 the production of the pig crop sacrifices the opportunity 

 of improving the herd by selection based on breeding 

 performance. Too often, also, sole dependence on gilts 

 results in a deterioration of the herd in size and feeding 

 capacity. 



The figures emphasize strongly the importance of raising 

 two litters every year from mature sows. Two litters 

 every year after maturity resulted in an average reduc- 

 tion of 45 cents a hundred in the cost of production as 

 compared with the system of raising only one litter 

 annually. 



Finally, the importance of the size of the litter as a 

 factor in economy of production is strikingly emphasized 

 by the results. With the smallest number of pigs to the 

 litter, the average cost of production was practically $1.25 

 a hundredweight greater than when the largest number 



