CIRCUMSTANCES AFFECTING PRODUCTION 185 



Milking the cows at equal intervals has reduced the 

 difference in fat content of milk from -93 per cent, to 

 03 per cent. 



8. Time of Calving. Trials carried out by the 

 Department of Agriculture for Ireland (1907-8) indi- 

 cate that the November calvers gave, on an average, 

 1 60 to 1 80 galls, more milk in a year than the April 

 calvers (see p. 199). 



Effect of Pood. 



Pasture is the natural food of the dairy cow during 

 the summer months, and if a sufficient supply is available 

 of " good quality," the milk-yield will most likely be 

 kept up to the maximum. It is very doubtful, in this 

 case, whether the feeding of concentrated foods in 

 addition to pasture would have any permanent effect in 

 improving the yield of milk, or the percentage of fat 

 in it. 



If, however, the pasture is only poor in quality, and 

 the cow is not receiving an adequate amount of nutrient 

 material in the form of forage crops, etc., the most 

 notable effect of the addition of suitable concentrated 

 food to the ration would be to increase the milk-yield ; 

 but there may be, at the same time, an increase in the 

 proportion of fat in the milk, z.., the milk may also 

 be, and possibly would be of better quality. Liberal 

 feeding of concentrates would therefore push the yield 

 of milk to the maximum ; above this point fattening 

 would most likely take place. The cost of producing 

 this increased flow of milk has also to be kept in mind. 



During the winter months, however, the pasture 

 grass, if available, has not the same feeding value, and 

 it is necessary on dairy farms generally, to lay up a 

 store of hay, straw, roots, and either home-grown or 



