FEEDING OF ANIMALS. 323 



exercising such care and reservation in regard to the num- 

 erous results of ourselves and others which are at command, 

 it may be taken as clearly indicated that, within certain 

 limits, high feeding, and especially high nitrogenous feeding, Highfeed- 

 does increase both the yield and the richness of the milk. !^f^^ 

 But it is evident that, when high feeding is pushed beyond a milk. 

 comparatively limited range, the tendency is to increase the 

 weight of the animal — that is, to favour the development of 

 the individual, rather than to enhance the activity of the func- 

 tions connected with the reproductive system. This is, of 

 course, a disadvantage when the object is to maintain the 

 milk-yielding condition of the animal ; but when a cow is to 

 be fattened off it will be otherwise. 



It has been stated that, early in the period of six years in Food ai- 

 which the Eothamsted results that have been quoted were lowa . nce 



i-Ti <••!*_• -it i graduated 



obtained, the amount ot oil-cake given was graduated accord- according 

 ing to the yield of milk of each individual cow ; as it seemed to y™ ld °f 

 unreasonable that an animal yielding, say, only 4 quarts per 

 head per day, should receive, beside the home foods, as much 

 cake as one yielding several times as much. The obvious 

 supposition is, that any excess of food beyond that required 

 for sustenance and milk-production would tend to increase 

 the weight of the animal, which, according to the circum- 

 stances, may or may not be desirable. But there remains 

 the important question — Whether the period of lactation is 

 lengthened, or the yield of the higher yielding cows is main- 

 tained the longer, by an increased amount of food ; or whether, 

 on the other hand, the period of lactation, or the yield of 

 milk, is reduced by the limitation of the supply of food? 

 The point is, at any rate, deserving of careful experiment and 

 observation. 



It may be observed that direct experiments at Eothamsted 

 confirm the view, arrived at by common experience, that roots, 

 and especially mangels, have a favourable effect on the flow 

 of milk. Further, the Eothamsted experiments have shown influence 

 that a higher percentage of butter-fat, of other solids, and of °/ d jff erent 



, P, r -i • -i • i -II • i •■! foods on 



total solids, was obtained with mangels than with silage as yield of 

 the succulent food. The yield of milk was, however, in a m%lk ' 

 much greater degree increased by grazing than by any other 

 change in the food ; and with us, at any rate, the influence 

 of roots comes next in order to that of grass, though far 

 behind it, in this respect. But, with grazing, as has been 

 shown, the percentage composition of the milk is considerably 

 reduced ; though, owing to the greatly increased quantity 

 yielded, the amount of constituents removed in the milk 

 whilst grazing may, nevertheless, be greater per head per day 

 than under any other conditions. 



