Breeding Selection
We chose the Angus breed in 1988 after experimenting with some other breeds. We did so because of the breed’s ease of calving, suitability for cooler temperate climates, well-established statistical information about individual breeding characteristics, and its premium prices in most markets. The following explains the criteria we apply when selecting cattle for breeding.
In summary we look for calving ease, moderate cow size and feed efficiency, fertility, good growth, carcase quality and sound structure. It is not possible in practice to find a perfect bull which meets all criteria equally well, and compromise is always necessary, taking into account the price the buyer is prepared to pay.
When we started the Hidval Angus Stud we aimed to breed good bulls for the commercial producer. Over the years we have raised our sights and steadily improved the quality of our herd. In Spring 2023 our sale bulls will be in the top fifteen percent of the breed as measured by the $A Selection Index.
Using Estimated Breeding Values
The Angus Society uses the Trans Tasman Angus Cattle Evaluation (TACE) program to generate Estimated Breeding Values (EBV’s) for a range of production traits. EBV’s are expressed as the difference between an individual animal’s genetics and a historical genetic level of Angus cattle. While EBV’s are important in selecting breeders, the percentage level of accuracy provided with each EBV should be noted. A low level of accuracy (less than 50%) means that the actual value of the trait could be within quite a wide range either side of the predicted value. For example, a 600 Day weight EBV with an accuracy of 50% will have a confidence range of plus or minus 16.8kg. At 90% accuracy this reduces to plus or minus 8.5kg.
Accuracy depends on numerous factors including heritability of the trait, accuracy of parental EBV’s, performance information available and correlation with other measured traits.
Despite these caveats, EBV’s provide a great deal of useful data for comparing the breeding value of Angus cattle, but obviously must always be compared with observation of their physical characteristics.
Calving ease
In using EBV’s to help select breeding cattle, we have two requirements that must be met before we consider other EBV’s. First, it is essential that they have strong positive EBV’s for predicted calving ease and moderate birthweight. It is basic to the economics of beef production to maximise the percentage of live calves on the ground. This avoids feeding unproductive cows, deaths of cows or calves during calving, and time lost in frequent inspections of heifers and yarding and assisting females with calving problems. We are sometimes surprised at how much buyers will pay for bulls with high birthweight and negative calving ease.
We give priority to breeding bulls with good calving ease, but it should be recognised that the bull only provides half the genetics, so if you have cows with poor calving ease then they may still have calving problems.
Mature cow weight
Second, we only buy bulls that are predicted to produce cows with a substantially lower mature cow weight than the bull’s estimated 600-day weight. Large-framed heavy cows look good in the sale ring but eat a lot to keep their big bodies going, and often lose condition faster than smaller cows when feed is not plentiful. Our aim is to breed moderate framed cows that can be run in larger numbers and produce more calves per area.
Historically, Angus cattle became too small, but this trend has been reversed in recent decades with the extensive use of United States Angus genetics and in our view is in danger of going too far the other way. The Angus Society has recognised this by discounting for high mature cow weights when calculating the Angus Breeding Index. Many breeders state that their aim is to produce efficient, fertile cattle but in practice high growth is often given more emphasis than other desirable characteristics that determine lifetime productivity.
Growth
After selecting for calving ease and moderate cow size, we seek a balance of other desirable attributes. We look for ‘curve benders’ which have moderate birthweights but subsequent high predicted rates of growth. Because we sell a high proportion of weaners, we particularly look for good growth at 200 days. As noted previously, we prefer a low estimated Net Feed Intake as an indicator of feed use efficiency, although this has the limitation of being based on feedlot performance.
We like bulls that we buy to have a high weight for age compared to the cohort they have run with. Actual weight sometimes tells a different story from the bull’s estimated EBV’s for growth.
Carcase
Good figures for muscularity and intramuscular fat are essential when buying bulls. The latter is not sufficiently rewarded in many markets for its contribution to eating quality. At auctions of commercial cattle often the only information available is weight and appearance. The importance of carcase information like intramuscular fat will hopefully be increasingly recognised as beef marketing becomes more sophisticated.
Rib and rump fat cover should be positive because they contribute to hardiness in cold conditions and provide a reserve for periods when feed availability is lower.
Fertility
Good scrotal size and shorter than average days to calving are indicators of higher fertility. To maintain a fertile herd, we sell any female which is not in calf when pregnancy tested after joining. Sale bulls can be fertility tested if 18 months or older: the test is not reliable before this age.
Temperament
We remove any animal which shows repeated signs of poor temperament. We do not buy bulls which have a low BreedPlan estimate for docility. But this figure does not always reflect reality because poor past handling can create bad temperament. Signs of nervousness can often be detected in the yards; for example the animal that constantly has its head up looking at you or is quick to move away.
Phenotype
Desirable phenotypical or physical attributes can be subjective: some semen catalogues suggest that certain bulls have ‘presence’. We do not like the noticeably concave backline that seems to be accepted particularly for bulls in the USA. Some buyers do not like the longer heads that are sometimes attributed to USA bloodlines. However, such considerations may be less important than the bull’s other qualities and must be balanced against these.
Freedom of movement is important to ensure that the bull can get around the paddock easily and serve females. EBV’s are available for claw set and foot and leg angle, but these must be checked visually. Many stud breeders use external assessors to grade these attributes and others like docility. Where these are scored on a scale of one to ten where five is ideal, we will only buy bulls scored mostly at five but no worse than four or six.
There are numerous other physical attributes that must be considered such as length, depth and thickness of body, muscularity, scrotal size and evenness, and sheath conformation.
Angus Selection Indices
The Angus Society calculates several selection indices for each animal based on its EBV’s. These can be used as a quick reference for the merits of the animal for different purposes. For example, the $A Index estimates the genetic differences in net profitability per cow joined in a typical commercial self-replacing herd. We aim to produce bulls which are in the top fifteen percent or better of the breed for the $A Index. To continually improve our herd, we only buy or use for AI bulls in the top ten percent or better. This is subject to the qualification that EBV’s change as new information is received, or if the Angus Society alters the basis for calculation.
The Angus Society will not reveal the weighting of individual EBV’s used to calculate the selection indices, only the weightings for groups of traits. We think that more detail would be helpful in understanding the nature of individual selection indices.
Herd Improvement and Artificial Insemination
As well as using our own bulls, we AI about 25 percent of our herd each year with semen from Australian, US or New Zealand bulls which best meet our breeding objectives. We give preference to Australian bulls. This has helped to bring about continued improvement in our herd over the years. Yearling bulls we will have for sale in Spring 2024 rank in the top fifteen percent of Australian Angus measured by the $A Index.
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