FEEDING DAIRY CATTLE

New Zealand Herald, Volume LXX, Issue 21617, 9 October 1933, Page 16

FEEDING DAIRY CATTLE

RATIONS AND MILK EXPERIMENTAL WORK A thorough study lias been made of the figures representing the detailed analyses of more than 1000 samples of milk obtained over a period of several years from cows fed widely different amounts of protein, tho rations ranging from 1:2 to I*l3 in nutritive ratio according to tho 51st annual report of tho Ohio Experimental Station. None of tho major constituents of the milk (fat, lactose, ash and protein), as ordinarily determined, were perceptibly increased or decreased by even tho most radical change in tho protein content of the ration. Tho properties of tho milk fat and the character' of tho milk protein were also unaffected by these changes. One minor group of constituents of the milk, often referred to collectively as non-protein nitrogen is tho only portion which appears to be regularly affected by the level of protein feeding. This non-protein nitrogen ordinarily comprises about 5 per cent of the total nitrogen of the milk. There was nearly twice as much non-protein nitrogen in the milk of tho cows receiving the 1:2 ration as in tho milk from those receiving tho 1:13 ration. Of tho several materials in this group, some of them unknown, urea was tho one most affected by the level of protein feeding, tho amount being eight times as much in tho milk from the 1:2 as in that from the 113 ration. Tests With Calves Six Friesian male calves were used in an experiment to determine the ellect of a whole milk diet upon the number of red blood corpuscles and the hemoglobin content of the blood and to determine tho value of copper and iron supplements. Three of the calves, acting as a check group, lot 1 received as their ration whole milk alone; the other calves, lot 2, received whole milk with copper and iron supplements. The experiment lasted approximately eight and a half months. Red blood cell counts and hemoglobin determinations were made at two-week intervals. Nutritional anemia was produced in those calves receiving whole milk exclusively. The addition of copper and iron supplements maintained the hemoglobin and erythrocytes at a high level. Some of tho calves in both groups exhibited external symptons of rickets. These observations were confirmed by blood studies, and after slaughtering, by bono ash determinations and breaking strengths of the cannon bones. Feed Value of Wheat Experiments have been conducted to determine tho feeding value of wheat for dairy cows. Two grain mixtures-were compared. One contained approximately one-half wheat with maize and oats making up the remaining half. The check ration contained only wheat, bran and linseed oil meal in addition to maize and oats. The results of these two mixtures were about on a par when fed with lucerne hay. A third group of cows, fed this wheat mixture continuously during tho winter period, produced normally and to all appearances suffered no ill effects from such heavy feeding of wheat. .In order to give wheat feeding an even more drastic trial, two cows wore placed on a ration composed of ground wheat containing 2 per cent steamed bonemeal with lucerne bay as the sole roughage. After four months 4 of this feeding these cows arc doing nicely. Therefore it appears that liberal amounts of wheat may lie safely included in dairy rations when prices warrant.