MILK YIELDS.

New Zealand Herald, Volume LXVI, Issue 20255, 15 May 1929, Page 16

MILK YIELDS.

Sir, —Mr. M. N. Trotter, member N.Z.J.G.8.A., has referred to my statement that the weight in milk production in the case of the average Jersey cow is 60001b to 70001b and sa\s it warrants correction. I would point out that the actual figures quoted by Mr. Trotter are the special records of a few Jerseys placed under C.O.R. testing during the year 1927. Let us consider the mature cow class quoted by him, 9669.91b milk. This was the average of 78 cows milking 553 days in the year and calving within 15 months. Undoubtedly they were specially selected cows, representatives from many herds and the best each breeder had to place under C.O.R. test, highly fed and nursed during their lactation periods and probably in some cases milked three times daily. Do these truly represent the records of the average Jersey cows, and are such records put up under average herd conditions year after year ? The average yield of butter-fat from these 78 cows with 9669.91b milk was 545.631b. Who will submit that 545.631b butter-fat is the yield from the average Jersey cow in the Dominion. The Dominion dairy record for a herd of 91 cows under the supervision of the Group Herd Testing Association shows an average yield of just over 4001b butterfat, the herd being a pedigree milking Shorthorn herd owned by Messrs. Conlan Brothers, Oroua Downs. The average test of the 78 Jersey cows under C.O.R. test is 5.64. On a return of 5001b butterfat average, which is not a bad one for a herd, this gives the total milk at 53191b, with 3501b butter-fat average, 62051b milk. I conclude that the figures quoted by me were, therefore, above rather than below the actual yield of the average Jersev cow. .A. W. Gbeen. May 14, 1923. '