Taking Stock: Cow or bull: where is the gain?

And in the past fortnight the 19-month-old heifer, Battalion Heartbreaker R16, has broken a Speckle Park world record, selling for $100,000, while the 13-month-old fullblood Wagyu heifer Sunnyside S0014 has set a new ceiling at $400,000 - the highest price paid at an Australian beef cattle auction.

But at the Sydney Royal Show three weeks ago I heard a statistic which surprised me.

In a judge's closing comments on a cattle class she said that up to 75 per cent of the attributes of a fresh crop of calves will be derived from the dam-side, and not from the sire.

So is it sire-power or the cow's influence that we should be concentrating on the most?

Will good cows "carry" a less favourable bull in a commercial setting? Or is it now more important than ever to select our bulls wisely?

Do we know the true value of our females? And are we paying for them?

What we do know is that one calf will receive about 50pc of their genetics from mum and 50pc from dad. And we know that in a single joining of 100 commercial females, the dam will contribute about 50pc of the genetics of one calf successfully born.

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Meanwhile, the sire will influence about 50pc of the genetics of 36 calves, assuming two bulls are joined to 100 cows with an 80pc conception rate after two cycles and a 90pc calving.

And that is why so much emphasis is placed on the bull, says one stud breeder from the Hilltops region.

Damien Thomson, with his family, runs Shaccorahdalu Angus, Berramangra, 20 minutes south of Yass.

"The cow contributes more to the performance of a calf by influencing its environment. Bulls on the other hand are a purely genetic influence and have no impact on environment," he says.

"We select bulls on temperament, structure, phenotype and estimated breeding values.

"In terms of making genetic improvement, the management of the cow side is responsible for improving the bottom end of performance while the bull side is responsible for increasing the genetic potential of the top-end of performers."

Of course, the ability of the cow to calve safely and to feed its progeny in the early months of its life has a significant impact on the progeny's performance. That learned behaviour to feed and to graze is from mum.

While commercial producers only select cows when choosing replacement females, stud breeders will select them specifically to purchase or to flush, culling them for less favourable traits, including late or no pregnancy, lameness due to structural issues and poor temperament.

"We improve the bottom line of fertility, structure, docility and longevity by continuously removing the underperforming ones," Mr Thomson says.

"This improves the performance of the herd, not the individual, and is a result of management practices, not genetic selection."

He says longevity in the cow herd is achieved by process of elimination.

"I think the most important thing for improving quality in our cows is to strictly cull underperforming cows to remove those poor genetics from the herd," he says.

And while some producers will select their replacements before joining, we could be culling the ones with favourable traits that we cant' see, like fertility.

The justification for this is to select progeny who we think will grow bigger or better - but the influence of fertility outweighs the influence of higher growth.

Meanwhile, bulls are bought in to improve the genetic potential in these areas.

Angus Australia says that too often, the value placed on a bull has a short-term focus, with high expectations on him and his immediate influence. It means that good bulls receive a less then representative assessment of the value they have delivered to a herd and poorer bulls receive higher praise than they deserve.

Just as one calf will receive about 50pc of their genetics from dad, he will receive about 25pc of his genetics from his maternal sire and 12.5pc from his maternal grandsire. Put simply, up to 87.5pc of the calf's genetics are from sires used in the past three generations.

It means that bulls will directly influence the siring of progeny for one to five years, they will have another three- to 10-year impact on the cow herd and a reduced impact on the cow herd in 20-plus years' time.

The contribution of cow and bull to overall profitability is far too difficult to calculate. And while that debate is interesting, it could be irrelevant. It doesn't lead to improvements; it's in delving into the individual aspects of genetic improvement where valuable insights can be found.

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