FARM NOTES.

Hauraki Plains Gazette, Volume XXXV, Issue 4670, 5 March 1924, Page 4

FARM NOTES.

A VALUABLE EXPBBIMENT. COMPARISON OF BREEDING. The 630,000 dairy cows In California produce annually about 100,0001 b of butter-fat, or a little less than 1601 b per cow. The latest figures available show that under present conditions a cow, in order to be profitable, must produce at least 2251 b of butter-fat a year. A majority, then, of the cows in tbe State are unprofitable, and if the dairy industry is to develop and keep pace with the demand of an ever-in-creasing population for dairy products the production of our dairy cows must bo Professor William M. Regan con--siders that this may be accomplished in two ways: (1) By better feeding and care of the cows that we already have, and (2) by producing better animals. A vast amount of work has been done on dairy cattle feeding and management, so that problems of better feeding and care are very well understood. But a consideration of the methods to be used in producing better animals reveals very little information of value. Very little experimental evidence exists, and there is lack of agreement among practical breeders.

A study of the methods used by practical breeders in their attempt ‘.b fix the transmission of high production in dairy cattle shows three methods that have been followed : (1) Inbreeding, (2) line-breeding, and (3) out-crossing. Bach method has its following. There are those who believe that to follow the method of line-breeding is to be insured 1 of success, whereas to in-breed is to meet with certain disaster. There are others who think in-breeding the most successful method to follow, while others practice out-crossing. rhe wild 'cow from whicji our present dairy cow descended gave very little milk, probably only enough to nourish her calf for two or three months at most. Through thousands of years of patient selection man has developed animals capable of giving great quantities of milk, until further progress can be made only with great difficulty.

Because of 'the fact that there is a tendency for the offspring of highproducing animals to revert in production towards' the average of the breed it is difficult to maintain the high production that has been developed m our better animals. Is thete some method of breeding by the use of which a breeder may be insured that the daughters of his high-producing animals will themselves, with a rea-. sonable degree of certainty, be piofitable animals? In other words, can we prevent this tendency io revert to the average of the breed ? Is there any merit in any of the systems of breeding now being used? If. so, which one of these is the best ? Is there any other system that may be used ?

These are .some of the Questions that the University of California, through its Department of Animal Husbandry, is attempting to answer for tlie dairy cattle breeders of the State, in a breeding experiment that is now being carried on in co-opera-tion with the Dairy Division of the United States Department of Agriculture.

The first part of this experiment is comparison of in-breeding to outcrossing as a means of fixing and in-, suring the transmission of high milk production. This experiment was started at the New Jersey Experiment Station in 1918. The cattle, 32 purebred Jerseys, together with four years of data that has been collected on them, have been recently purchased by the University of California, and the animals are now at Davis. The experiment started with three Jersey bulls and 18 cows. These three bulls are unrelated. One of. these, Lucky Fern, is a son of Lucky Farce, a cow that until recently held the world’s record as a yearling. At present we have a number of his daughters which are about to freshen. The second bull is Pogis Torono Experimenter, a son of Exile’s Bonnie Gold Bug, by Options Pogis of Lusscroft.

The females of the Jersey group are divided into three groups. Each grouo is mated with one of these bulls. The females resulting from the first mating, or the first generation of female progeny of each bull, are bred directly back to their sires. The females resulting from this mating, or the second generatioin of inJired animals, will be mated again with their sire, giving the third generation of in-bred females. These will contain 87.5 per cent, of the blood of the sire. After the (i--st generation of in-bred animals has been mated back tp. the sires, in the next breeding they will be out-crossed on each of the other bulls in the experiment. Likewise, the same comparison will!be possible with the second and third generations. The effects of these two methods of breeding will be detertained by direct comparison. Three generations of inbred heifers will be compared with three generations of out-cressed heifers.

Complete records are being kept on every animal in the experiment. The effect of the different systems of breeding is noted by comparing : (1) The production of the animals ; the amount, of milk and the per cent, of fat is taken daily from each cow. (2) Size and development; the animals are weighed, and height measurement (at withers') is taken monthly from birth. (3) Constitutional vigour; measurements of heart girth are taken monthly. (4) Reproduction; complete breeding records, are being kept, including data on size and vigour of calves, age at sexual maturity, sterility. susceptibility to abortion, and sex ratios. (5) The general conformation of all animals is recorded by pictures.