INFLUENCE OF FEEDING.

Dominion, Volume 5, Issue 1405, 3 April 1912, Page 8

INFLUENCE OF FEEDING.

SIDELIGHTS Ob' EXPERIMENTS. A controversy has been proceeding in tlio American dairying journals upon the point, of tlio possibility of increasing ttio proportion ot butter-rat in a cow's .milk by special feeding, l'rol'essor (J. JI. Ecklcs, of iussouri Agricultural College, has wnlten instructively on the subject, ami his statement of the ease can nuvantagcoiiily Ik quoted. He says: "lor. a number of vears the question of increasing the-per cent, of fat in.milk has been a subject of discussion .at almost every farmers' meeting. Tlio limner, as a rule,.assumes thai tlio richness'of the milk can be-in-creased by heavy feeding. College and experiment station men, basing their conclusions upon tlio results of numerous investigations in different parts of the world, teach that the percentage of butterfat cannot be influenced by the character of tho ration, except as the. work done at the New York Experiment Station indicates that phosphorus compounds may produco a slight effect. "During tho last few years considerable data have been gathered in our experimental work here with dairy cows which indicato that it is possible in another way to increase the percentage, of fat to ,an .abnormal degree for a short time, and probably to a less degree for a longer ! time. The rule .seems to be that wnen tlio ration of a' cow is insufficient to support her milk production and she draws on the fat stored on her body, that tho percentage of fat in the milk is increased, -"in the course of one of our investigations a. flolstein heiier calved in as lat condition as was possible to get her by continuous heavy iceding from birth. Another heifer, of practically the same age and breeding, was fed trom birth until she came in milk on ration of skim milk and hay without any grain whatever. As_ ■a consequence, she was decidedly thin at' calf birth. The milk of the heifer in good condition tested over 1 per cent, at the start, while the milk from the one in thin condition tested about 3 per cent. The fat heifer declined in weight tor several weeks and during this time continued to show a high percentage u* lat. When her weight became stationary her percentage of fat declined until it was practically the same as the other. The thin heiier made no decline in weight, and showed no decline in the fat of her milk. Eater she began to gain in live weight, she having been put on a liberal grain ration immediately after calving, tier percentage of fat increased slightly until the two became practically together. Similar results have been obtained with two other pairs of heifers under similar treatment. The most marked example of how this works out is shown in the tollowing:— "A mature Jersey cow was fed a liberal ration for two months before calving, in order to get her unusually fat. Immediately after the birth of the calf, she was put on a ration that was sufficient only to maintain her body weight, according to the maintenance values as usually estimated. She was fed for 30 days on a ration of 3SIb. grain and 71b. hay a day, which was estimated body maintenance. At tho beginning she produced 211b. of milk a day. During the 30 days the de- i clino in milk was very slight. Indeed, | at the end of the 30-day period she was producing I'JIIb. a day. During this time she lost 1151b. in live weight. In the beginning she was smooth and excessively fat for a Jersey cow, but at the end of the | 30 days she wa's decidedly thin and emaciated. Beginning with the 28th day it was ob-erved that she was becoming weak and she staggered as she walked. "On the 29th day she could scarcely get un when down, yet she produced 1911b. of milk. It was not considered safe to continue the test any longer and her ration was increased to a normal amount. During the 30 days this cow produced milk continuously without any feed whatever to supply' the nutrients. It is evident that th? solids in the milk must have been taken from the body, and the decline of 1151b. in weight shows this was the case. During the 30 days, <131b. of fat and 521b. of other solids were produccd_ in the milk. The average percentage of fat during the 30 days was fi.fl; the normal test for this cow is slightly under 5 per cent.' Within 48 hours,after her feed was increased, at the end of the 30-days period, the percentage of butter-fat in the milk declined abint'2 per cent. If a cowwill nroduce milk for a month without having anv food to furnish the neeesasry material, it is evident that tho effect of any feed cannot be measured in a short period. In an experimental way it also has a bearing on methods of carrying out many lines' of investigation, as, for example, the effects of feeds on the compositions of milk, since here we will have to avoid the probability that milk fat taken from that stored in the body and secreted in the milk is if different composition from normal milk fat."