PROGENY TESTING

Bay of Plenty Beacon, Volume 08, Issue 91, 20 July 1945, Page 8

PROGENY TESTING

INCREASING BUTTERFAT PRODUCTION USE OF PROVEN" SIRES The following article has been supplied to us by Mr N. Secretary of the Eastern Bay of Plenty Herd Improvement Association:— We read with interest in the Beacon issue of the ,10th instant the 9 suggestions for increasing buttcrfat production put forward by an Opotiki farmer Mr J. Armstrong. J There is no doubt that Mr Armstrong is on the right lines when he suggests that thousands of potential producers, are slaughtered as bobbie. calves every year } particularly as quite a large percentage of these would, be heifer calves. Compulsory testing has often been suggested by people enthusiastic for general Herd but with our twenty years experience of Do-minion-wide Group Herd Testing on the voluntary basis, we do not suprport compulsion. Rather would we have the individual costs of testing to farmers reduced by the Avhole Vlairy industry of New Zealand agreeing to submit to a levy on butterfat to be used for this purpose. The industry as a whole is at present benefiting from the Herd Improvement work carried out every year by one-fifth of its members, who bear the whole cost apart from a small subsidy received from the Government and the Dairy Board. Group Herd Testing to be valuable from a national point of view, must have the redely co-operation of its members. The proper identification of cows particulars of age } calving dates etc., the tattooing of calves with recordingj of sire, as well as dam must be carried out conscientiously and correctly. Wcruld this done uiulcr compulsion? A large number of farmers could not supply this information even if they were agreeable. Branding of Cull Cows Mr Armstrong's suggestions re-

garding the branding of cull cowls 1 are not new to us. This lias been a problem we have often considered. "Let the buyer beware." We have a national system of identification by tattoo available for all Group Hei'd tested and will supply certificates of production for any of these. Further, owing to the wide variation of feeding and management from farm to farm one farm--9 ers culls are often payable producers on another farm. The reverse is often brought to our notice. A farmer buys a -1001b fat cow from a good nutrition takes her home and on, poor feeding and management gets 250 of fat or less!. He feels that he has been 'deceived.. Better feeding and management alone would have a marked effect on total Dominion production. "Marked" Calves Mr Armstrong's information on "marked" calf standards is a little out of Jdate. The standard for the "marking" of calves from mature cows used to be as he suggests 300 lbs of fat in 305 days; and the sire had be. a registered pedigree bull of certified standard of butterl'at back-j

ing. However since 1936 we have been carrying out extensive sire survey investigational work anld found that from a national point of view, the i herd sires arc ot greater importance than the individual cows with which they are mated. Progress is very .slow when attention, is given only to performance of dams. As a result all calves from herds under test are identilied by tattoo lid the oars soon after birth. These calves are known as identified calves and the only qualification requijed is that the dam and sire be kn »wn by the testing member—irrespective of their breeding or butterfat ability. This is the. foundation, of our sire survey work. The term "marked calf" was used in conjunction wilh the use of the 'T tattoo mark, and certain standards of breeding and butterfat backing Avere required of the parents. The use of the term "marked" has been discontinued and the T tattoo is only aidded to the identification marks of calves sired by a "proven" 50 per cent, of whose daughters have produced 3501bs of or whose daughters show' a sufficient improvement on their

dams to warrant classification as equal to a 35011) standard. These calves arc known as "merit" calves and. are of such quality that they arc not often ofTerekl for public sale. Sire survey makes possible a great advance in Herd Improvement in the future. "Approximately 12 to 15 heifer calves Avill be sired by the average, bull and as he lias a working lifetime oL approximately three to four years, it follows that some 40 to 50 heifer calves would be available from the average butt as compared with 2 or 3 heifer calves from the average cow. Therelore the bull is, about twentj" times more important than the average cow in determining the quality of future generations pf dairy stock." There is a definite advantage in selecting calves from the highest producing half of the herd, but the difference is much smaller than is generallj- appreciated. Actually the difference, is only 15 to 20 per cent, of the difference in the production of the dams. The highest producing cow in the herd, does not always leave a high producing daughter—in fact an extensive analysis of surveys shows that in 40 per cent, of cases tlip daughter of the top cow was lower in production than the average of all whereas in the same proportion of cases, the daughter of the lowest producing filam in the survey was better than the average of all daughters. To the 30/11/44 surveys have been made of 1833 sires in the industry. This included the comparison of 26 } 839 daughter-fclam pairs. 2G per cejit. of the sires were leaving daughters better than their dams. 28 per cent, of the sires were leaving daughters equal to their dams. 46 per cent, of the sires were leaving daughters lower than their dams. These figures are alarming when it is realised that it is the 1 more progressive farmer intent on improvement who spares no effort to obtain better sires ? places them under survey and gets, these results.

On the other side of the ledger however it must be conceded that these bulls got into tested herds ■which arc better than average for the same reasons. Sire survey is the comparison of actual production under test of all of the daughters of the 3irc with the actual production under test of the dams of these daughters. It is the only really worth while progeny test, as all of the available daughters must be included. Space cannot be taken up here to explain the technique or interpretation of sire survey. But enough has been written here to assure readers that the industry now has Herd Improvement on a sound basis. Any further information required by farmers or others interested in increasing butterfat production may be obtained by contacting the Manager of the Bay of Plenty and East Coast Herd Improvement Association Box 79 Wha'katane or the N.Z. J t Dairy Board Consulting care of the. same address.