210 SWINE 



tation with a cow is approximately nine months, and the 

 period of lactation from nine to eleven months. Thus it 

 will be seen that a cow for a considerable portion of each 

 year is caring for two offspring at the same time; one is 

 being developed within while the other is being cared for 

 at the udder. In dairying operations this is still more in- 

 tensified. Such a cow has been developed to give suffi- 

 cient milk for two or three calves which is taken from her 

 artificially and used for commercial purposes while at 

 the same time she is producing a calf annually. In the 

 case of a mare conditions are the same as for the beef cow 

 except that the period of gestation is somewhat longer, 

 and the period of lactation not quite so long. 



A sow may be bred, and then may farrov^^ and raise her 

 litter within six months' time. Thus she can produce two 

 litters a year and never be caring for more than one at a 

 time. With this in view it can easily be seen then that a 

 sow, with proper care and feed, should be able to produce 

 two litters a year as well, or even better, than the cow 

 can produce one calf a year. All this is borne out by the 

 facts, namely, that if sows are properly fed and cared for 

 after coming to maturity, they can produce two litters 

 annually and do it apparently just as well as to produce 

 only one. If there is any difference the advantages seem 

 to be in favor of two litters per year, because if the sow is 

 allowed to go over one season, or produce only one litter 

 per year, she is likely not to be so sure a breeder as if she 

 were bred immediately after weaning the litter. 



The arguments for the statement that sows can pro- 

 duce only one good litter per year apparently originated 

 from the fact that very often swine are not as well cared 

 for as they should be and are considered only as the scav- 

 engers of the farm, allowed to get along as best they can 



