Measuring Performance Of Cattle

Press, Volume CV, Issue 30953, 8 January 1966, Page 10

Measuring Performance Of Cattle

Real progress In the improvement of New Zealand beef cattle herds can only be achieved by a marriage of the practical skills of the breeder and the knowledge of the scientist, Mr I. M. Caimey, executive officer of the New Zealand Meat and Wool Boards’ Sheep and Beef Cattle Survey, said in an address to the annual meeting of the New Zealand Aberdeen Angus Cattle Breeders’ Association in Dannevirke.

Mr Cairney complimented the Angus breed association for its forward-looking policy of encouraging practical research into producing, under New Zealand conditions, the most suitable type of beast required by the meat trade.

Both the breeder and the scientist can contribute much and without full-co-operation rapid progress in herd improvement is impossible, he said. There are now 100 herds over New Zealand including four beef breeds participating in this scheme. The New Zealand Sheep and Beef Cattle Survey has established a committee with representatives from each beef breeders’ association to keep in touch with this work.

Aim For Quality “Our objective is to breed cattle which will produce the greatest quantitj of meat of the highest quality in the shortest possible time, with the smallest quantity of feed. In this endeavour there are a number of important considerations. These are: regular breeding for high calving percentages; fast growth; milking ability and heavy weaning claves; and carcase; quality. Growth rate is universally acknowledged to be the most important step towards progress in beef cattle herd improvement. “Weight gain performance testing depends on two principles—animals with the capacity to make good weight gains pass on this quality to their progeny—it is strongly inherited. Relative weight gains between different animals can only be determined effectively by weighing.

“There are a number of general considerations about weight gain performance testing. Breeders should regard it as an additional valuable tool which they can use to select their most productive cattle. It is of particular value in detection of animals and breeding lines which are poor

producers in spite of attractive appearance and conformation. Culling of these is important as one of the main aims should be a high average level of production in our stud herds. Stud cattle with this genetic quality for high production must raise the level of production also in our commercial cattle.

“The aims are well stated in the introduction to the booklet describing the scheme being operated by the American Angus Association. Today’s tools are not designed to alter the type or kind of cattle we have been breeding. Rather, they are inteded to identify and propagate more of those animals which come closest to meeting the requirements of the breeder, feeder, packer, retailer and consumer.

Warning Issued “It must be stressed that because of differences of feeding and environment in weight gain performance testing, comparison must not be made between herds or between animals in different herds. In fact, valid comparisons cannot be made in the same herd between animals or groups of animals on different levels of feeding. In this regard care must be taken on the question of nurse cows. “Weight gain performance testing does not replace the skill of the breeder but rather provides him with more precise methods for the exercise of his judgment and skill. Other features of animals which are related to production must also be considered —for instance feet, jaws and temperament. There is, of course, a record of the performance of animals which is much more permanent than a breeders’ memory, very good as these often are. There is strong evidence that these cattle, with good weight gaining ability are efficient users of their feed and have good carcase quality. There is great difficulty in herd improvement based solely on eye

appraisal of conformation, because we cannot see what is under the skin and frequently what should be good red meat is fat or other undesirable tissue, which is not wanted by anyone.

“Now for the operation of the scheme itself. Each herd is visited with mobile scales and on the average we can weigh cattle at the rate of one a minute. A nominal charge has been made and this covers nearly half of the cost All male and female calves in the herd should be weighed. “There are two main weighings of each animal—at weaning and finally at about 18 months. In addition we have made an intermediate weighing, but this is not essential.

“Weaning Weighing This is purely used as a means of selecting the best cows in the herd—those that wean the heaviest calves. Culling of cows which would wean light calves is of course very important.

Final Weighing “Each weight is adjusted to bring the calves all to the same age—by adding or subtracting the gain for the number of days concerned. Further adjustments are made to allow for cows of different ages 15 per cent, 10 per cent or 5 per cent is added to the weight of 2YO, 3YO and 4YO cows calves. The final list shows the number- of pounds above or below the herd average of the adjusted weight of each calf. The average daily gain for each animal is also shown.

“Final Weight at About 18 Months —This weighing is carried out at the same time as the weaning weighing of the subsequent season’s calves. It shows the animal’s own capacity to make good weight gains. This has, of course, been inherited by it and will be passed on to its progeny. “The figures returned to each breeder show final weight gain since weaning and average daily gain for each animal. Weights are again listed showing how much they are above or below the herd average. All figures are treated in strict confidence.

“The principles of using this information for herd improvement are: (1) Bulls and replacement heifers should be retained from high producing cows only. (2) Select your top group of cows—those which wean the heaviest calves, (3) Mate these top cows to fast weight gaining bulls.

“What results can be expected from the use of weight gain performance testing?”

“(1) There is very little New Zealand data to answer this question. However, some work done by Ruakura Animal Research Station showed the progeny of fast gaining sires to average 251 b heavier than the herd average at 550 days and the progeny of the slow gaining sires to average 251 b lighter than the herd average—that is 501 b difference in weight between the two groups, i.e., between the best and the worst progeny.

“(2) In one large herd in New South Wales where this selection has been practised it was found that bulls which gain jib per day more than their mates up to 15 months of age sired progeny which as yearlings averaged over 301 b heavier than the progeny of the slower gaining bulls. This indicates the capacity of good bulls to transmit high weight-gaining characteristics of their progeny.

“(3) In this same herd in New South Wales culling of cows with light calves at weaning has given an overall average weaning weight increase of 151 b in three years.

“A comparison of the weights of calves weaned by two cows of the same age, similar conformation, run under identical conditions and sired by the same bull further illustrates the value of selection of cows on the correct weaned weight of their calves: