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BREED SOCIETIES | |
Breed Improvement of Maine Anjou Beef Cattle in New ZealandMany beef cattle producers point to low current International prices and dependence on trading of commodity products as a major cause of our current beef price downturn. However examination of beef prices from 1970 to their projected values in the year 2000 show that real beef prices in 1997 dollars have fallen from an estimated $3.70 per kg in 1970 to around $1.80 per kg in 1997 suggesting a gradual decline in real returns from beef production over a thirty year period (Figure One). In the face of declining incomes, some beef cattle producers choose to retrench and decrease expenditure and also lower productivity. However other beef cattle producers offset this decrease in price by increasing the economies of scale through purchasing more land or increasing the efficiency of production, thus making greater use of existing resources. One method of increasing the efficiency of production is through seeking and exploiting genetically more profitable animals for your beef cattle production system. Figure One: Trends in Real Beef Prices (1970-2000 est.)
Some industry commentators compare the beef industry with that of the dairy industry and point out that higher incomes from dairy production result from either higher prices or improved management. Figure Two shows the inflation adjusted milksolids price from 1950 to its projected level in 2000. Real milksolids prices have declined at approximately eight cents per year over this fifty year period. However the dairy industry has been able to offset this decrease in price somewhat by increasing production through changes in management. One area of management change for the dairy industry has been an accelerated rate of genetic improvement accomplished by using modern genetic and reproductive technologies such widespread AI. Figure Two: Changes in real milksolids prices (1950 to 2000 Genetic improvement of any livestock species should focus on selection for economically important traits. The relative importance of such traits will differ depending on which perspective we take, traits of importance should meet the requirements of:
Using cow weaning rate as an example of traits differing in importance between sectors of the beef industry, his trait is of considerable importance to beef cattle producers but of no importance to processors or beef consumers. Saleable meat yield is of primary importance to processors but little interest to consumers. Traits such as meat tenderness, taste, juiciness and flavour are all important to consumers but are of little importance to beef cattle producers when they are not financially rewarded for improving such traits. Objectives of a Beef Cattle Breed Society A beef cattle Breed Society often has a range of objectives, some of which relate to improvement of the cattle and others of which concern the well-being of the Society and its members. Three objectives frequently quoted by many Breed Societies include:
Often the major goal of beef cattle Breed Societies tends to focus on promotion and marketing related activities such as showing cattle and publication of articles for magazines. It has been recently estimated that in United States beef cattle Breed Societies as much as 70% of total expenditure has been on promotion related activities. In contrast, a relatively small portion of funds are spent on breed improvement which includes developing a performance recording package and obtaining Estimated Breeding Values (EBVs) on cattle. However, performance recording and genetic evaluation (the process where EBVs are obtained) can contribute to sustainable improvement of a breed provided these measures are used to improve traits of economic importance. Maintaining breed purity does not directly contribute to Breed Improvement unless one requirements of reaching a purity status is that animals must be performance recorded and breeders base their selection decisions on these performance records. Ingredients for Successful Breed Improvement A number of key elements are required to ensure the success of any breed improvement programme. Firstly motivated breeders should be selecting cattle which are genetically superior for traits of economic importance. Figure Three - Elements of a Beef Cattle Improvement Programme
To drive this genetic improvement requires committed buyers who will purchase bulls if they will increase profit for their own farming conditions. At the other end of the spectrum a database containing pedigree and performance information such as birth weights and weaning weights. BV processing is simply using pedigree and performance information to calculate a series of Estimated Breeding Values (EBVs). Research may be focused on determining what customer requirements are (what bull-buyers want) and how EBVs can help meet these customer requirements. Finally, extension should focus on ensuring that breeders are comfortable with using EBVs for making selection decisions and that bull-buyers are able to use such information to improve profitability of their herds. Three essential ingredients are required for successful Breed Improvement, these are:
In New Zealand we have some 64,000 cows (all breeds) within registered herds and 1.3 million cows within commercial herds. Improvement in registered herds relies on selection for traits of economic importance. However, for our beef industry to obtain maximum benefit from this improvement, superior genes (in the form of bull sales or semen) need to be transferred from registered to commercial herds. This can be accomplished through selling bulls and semen. Breeders can be motivated to sell more bulls if they receive a higher price per bull sold. Likewise bull buyers will be encouraged to purchase bulls for higher prices if they are convinced these bulls will increase profit for their farm. It is important to determine which of these ingredients (improvement, transfer of bulls or cash-flows back to breeders) is limiting progress for a particular breed. If improvement within registered herds is limiting progress for your breed a greater uptake of performance recording and genetic evaluation will be required. If a low numbers of bull sales result in sub-optimal cash-flows then market research is required to determine the needs of your bull-buying customers and then meeting or exceeding these customer requirements. Table One: Some selected beef cattle populations in New Zealand
An important feature of Table One is that for each breed the number of commercial animals greatly exceeds numbers within registered populations. From a breed improvement viewpoint there are limited opportunities to select genetically superior animals from within registered herds since there are only few animals within registered herds. In contrast, commercial herds contain vastly more cattle and thus provide a valuable opportunity from which to select superior cattle. Suppose a method became available to identify genetically superior cattle for meat tenderness, if this method were applied to 28 000 registered bull calves born annually, a few individuals could be identified. In contrast however if such technologies were applied to some 500 000 bull calves born in the commercial sector many more superior individuals could be identified. In this instance, some bulls calves born in commercial herds might become very desirable as for use as breeding bulls or alternatively, through sire trace-back their own sires might be identified from within registered populations. Where does this leave New Zealand Maine Anjou breeders ? Firstly, recording Maine Anjou crossbred cattle may allow some superior individuals to be identified for traits such as meat tenderness which would otherwise not have been identified. Such animals can be used within breeding programmes. Secondly, animals can be evaluated for traits which usually cannot be measured from within registered populations. It is likely that the majority of registered cattle are sold for breeding purposes and that very little carcass and meat quality data is collected for selection purposes. Maintaining a large database incorporating carcass and meat quality traits would enable sires with superior merit for such traits to be identified. This requires recording commercial cattle. Grading Up Some Breed Societies are very stringent in their requirements for breed purity. As an example, the former Maine Anjou grading up requirements were that purebred Maine Anjou cows could be 15/16 pure whilst bulls were required to be 31/32 pure. Figure Four Grading Up Process Requiring Five Generations
This grading up process required four generations to reach purebred status for cows and five generations for bulls. Given that the average age of beef breeding cows in New Zealand when their progeny are born is five years, then on average it would require 25 years to reach purebred bull status. Figure Five Grading Up process Requiring Three Generations
It would be desirable to shorten this grading up process so that breeders can selects bulls and females from a larger pool of available animals. For example, if the Maine Anjou breeding cow herd is currently 700 cows in New Zealand, then approximately 300 potential breeding bulls would be born annually. If through decreasing the purity requirements the breeding cow herd increased to some 2000 cows then 900 potential breeding bulls would be born annually. A greater selection intensity and consequently higher potential rate of genetic progress is possible when there are larger numbers of bulls available to be selected from. Figure Five shows an example grading up process requiring only three generations to reach the status of purebred sires. This grading up process now allows purebred females and males which are 7/8 to be considered as pure-bred. Note that in this case selection is through the female line, that is superior dams are selected to breed ¾-bred and 7/8-bred cows. Opportunity exists to use bull selection to grade up to purebred status. In this example, both females in addition to bulls can be used to achieve purebred status. The advantage of using bulls as well as females to grade up to purebred is that the intensity of selection is much higher for bulls than for females and thus the few most superior bulls (say the top 2 bull calves from a mob of 50) be selected rather than selecting the top 50% of heifer calves annually. Figure Six. Alternative Grading Up Strategy using bull selection
One advantage of the new grading up schemes are the higher selection intensity from including foreign genes (from both overseas Maine Anjou cattle which were previously not eligible for registration and from other breeds) into the New Zealand Maine Anjou breed. Another advantage of alternative grading up schemes is that New Zealand Maine Anjou breeders can capitalise on databases built up by overseas Breed Societies which may contain EBVs for a large number of traits. Disadvantages of a new grading up scheme are that undesirable genes may be introduced into the Maine Anjou breed such as extreme size. Since it would be the responsibility of Maine Anjou breeders to determine their own breeding objectives, it is unlikely that such extreme cattle would be introduced into the breed. Another possible disadvantage of the new grading up schemes is that some Maine Anjou breeders may relax within-breed improvement and rely on other breeds for future genetic progress. The practicality of introducing cattle from other breeds is somewhat limited at this stage by the fact that we cannot as yet directly compare the genetic merit of Maine Anjou cattle with those of other breeds In conclusion, breeding Maine Anjou cattle which meet requirements of commercial cattle farmers and modern beef markets requires prudent use of all possible sources of genetic improvement. Introduction of outside genes will only be successful if coupled with increased adoption of a genetic evaluation by New Zealand Maine Anjou breeders. Paul Charteris and Dorian Garrick
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