The New Zealand Hereford Association is involved in an International Genetic Evaluation – Group Breedplan Programme. The Australian Hereford Society, the Australian Polled Hereford Society and the New Zealand Hereford Society (in which horned and polled breeds are combined), combine their databases to produce an Australisian (Trans-Tasman) Genetic Evaluation for white faced cattle.
This has a number of advantages:
- A larger database of performance records leads to more accurate estimations of EBV's.
- All breeders in these three societies have their cattle ranked in a comparable way.
- Marketing of breedplan cattle is enhanced as all are evaluated on the same standard.
The service is run by the Agricultural Business Research Institute (ABRI) at the University of New England, Armidale, NSW., Australia. Breedplan research and development is carried out by the Animal Genetics and Breeding Unit (AGBU), also at the University of New England.
Breedplan is all about increasing accuracy of selection decisions, and when properly understood and used, can be a significant aid to a cattleman's decision making when selecting stock and can be used to estimate the relative performance of an animal or its progeny compared to the herd or breed benchmark.
Note: Breedplan is the same technology that has been used by the pig, poultry and dairy industries to make such dramatic production changes over the last decade or so. It has worked wonderfully well for those industries, and works just as well for the genetic evaluation of beef cattle.
What you see in an animal is the result of both the genes they inherit from their parents and non-genetic effects such as feeding and parasite control, sex, age of dam etc.
To improve your herd by selection, you need to evaluate the genetic merit of cattle - that is the proportion of the animals performance which is controlled by its genetics, and not its overall performance which has been influenced by environmental and other non-genetic effects.
The final evaluation of how an animal will breed (its true breeding value) is never achieved until long after the animal is dead. Fortunately, its estimated breeding value (EBV) can be calculated by using analysing performance information, from both the animal itself as well as from its progeny and close relatives, and adjusting for known heritability factors and non-genetic effects.
AN ESTIMATED BREEDING VALUE IS THE ESTIMATED GENETIC MERIT OF AN ANIMAL FOR EACH RECORDED PRODUCTION TRAIT. EBV’s reflect the difference that can be expected in an animal’s performance relative to the breed baseline of zero for each trait. On average, half of this difference will be passed on to the animal’s progeny.
Breedplan represents a major improvement over the more traditional methods of performance recording. It uses all the records available on the animal and its relatives to disentangle genetic and environmental factors, giving the best estimate of the animals breeding value that is possible from the available information.
To allow comparison of animals from between management groups or even different properties genetic links between contemporary groups are essential. A genetic link is achieved when animals in one group/herd have a parent in common with an animal in another group/herd. For sires, this cross linkage is usually achieved through AI but could also be through common dams.
Breedplan uses "multiple trait" evaluation which further increases the accuracy of the EBVs. There is usually an association between two different traits; this may be positive or negative and vary from weak to strong. For example, 200 day weight has a positive association with 400 day weight - that is, as 200 day weight increases so does 400 day weight. These associations between traits are taken into account when carrying out the evaluation and are particularly beneficial when animals have a limited number of relatives with performance records.
The multiple trait analysis also helps to reduce the "bias" which can be introduced by a previous selection decision, for example selective joining or dis-proportional culling. For example, selection of heavier calves at weaning is expected to lead to higher than average 400 day weights. The fact that the remaining animals are expected to be heavier as a result of previous culling is accounted for in Breedplan as long as the records on which the earlier selection was based are included in the evaluation.
The EBVs, expressed in the same units as they were measured (eg, kg) and are calculated relative to the breed benchmark of zero, which was established some 20 years ago when the first performance information was recorded.
It provides the best estimate of an animals breeding value from the information available.
EBVs are more accurate than conventional indices of cattle performance, such as ratios, which is why their use in selection allows genetic progress to be greatly accelerated.
Breedplan is a useful aid to selection, not because you are a poor judge of cattle but because when it comes to making simultaneous adjustments for known environmental effects over a number of traits, human brainpower is no match for a computer.
Observed differences of performance between animals resulting from environment can be large, but are not inherited by their progeny, and as such can lead our selection decision astray. Genetic factors are the result of genes inherited from the parents and are the blueprint for future performance, both of the individual and its progeny.
You buy a bull not for what he looks like but how his progeny will perform. It is only when environment factors are either standardised or adjusted for that real genetic differences become apparent. Breedplan uses sophisticated computing technology to adjust for known environmental effects over a number of selection traits.