MILK PRODUCTION 435 



Relative milk-giving capacity. But little information 

 can be given with reference to the milk-giving capacity 

 of any of the classes of live stock, except cows, that is based 

 on American experience. Nor can it be said that the 

 question is greatly important except in the prospective 

 sense, that is, in so far as it relates to the possible sources 

 other than cows, from which milk may be obtained. In 

 discussing the question, therefore, something may be said: 

 (i) Regarding the milk-giving capacity of cows; (2) the 

 probable milk giving capacity of other domestic animals, 

 as mares, ewes, and female goats, usually spoken of as 

 nannies and (3) the probable sources of milk production in 

 the future. 



The difference in capacity in cows to give milk, is 

 simply surprising. In well regulated dairies, 6,000 pounds 

 a year per cow may be set down as the minimum of pos- 

 sible production. It would be safe to affirm that the average 

 annual yield of all the cows milked at the present time in 

 the United States and Canada is not more than half that 

 amount. With individuals of some breeds and also of some 

 grades, it is easily possible to obtain 10,000 pounds of milk 

 a year without resorting to feeding unduly forced. For 

 the facts regarding maximum production, see page 418, and 

 for the discussion of the influences that affect quantity in 

 production, see page 424. 



While no data based on American experience with 

 reference to the amount of milk produced by mares dur- 

 ing lactation is available, the average amount given by a 

 mare is fully equal to and probably more than that given 

 by the cow which merely suckles her calf up to the period 

 of weaning. Basing the amount of milk given on the in- 

 crease in the weight resulting, the average foal will con- 

 sume more milk than the average calf. It would seem 

 probable, therefore, that mares could be so managed as to 

 produce milk yields fully equal to those of cows. At the 

 Wisconsin experiment station it was ascertained that 

 through weighing the lambs, both before and after nursing, 



