100 Pork Production 



ing her fourth litter. From the fourth litter on, she may 

 be expected to produce a decreasing number with each 

 succeeding litter. The number of sows with records 

 here of seven, eight, nine, or ten litters is too small, how- 

 ever, to make the averages for these litters reliable. The 

 extreme fluctuations shown in the latter part of the 

 curve would be made to disappear if a larger number of 

 records of these litters was available. As a result of this 

 limitation of numbers, the dotted line is the more reliable 

 indication of the average performance. 



No attempt was made in this study to allow for 

 a sow producing two litters a year. It is believed, 

 however, that she will as closely approximate the curve 

 shown, as she would if producing but one. The large 

 increase of the second litter over the first was probably 

 due to the fact that few of the young sows produced their 

 second litters without a rest of six months. The average 

 size of all the litters here reported was slightly over nine 

 pigs, which is probably above the record of the average 

 herd. This, however, would not tend in any way to 

 change the general direction of the above curve. 



Feeding and condition of the sow. 



That the way a sow is fed the week or two before breed- 

 ing exerts an important influence on the number of eggs 

 secreted when she comes in heat and the consequent 

 size of the resulting litter is strongly supported by the 

 observations of the best hog-men. It is not so much 

 the direct effect of the feeding alone which is believed to 

 produce this result, as it is the state of health and breed- 

 ing thrift brought about by the proper combination of 

 judicious feeding and liberal exercise. Thin active sows, 

 when fed liberal rations before breeding, respond to the 



