NSW DPI beef industry leader Bill McKiernan, who has headed the beef cattle breeding selection program since the 1990s.

A preoccupation with assessing females for visual traits of dubious value at weaning or yearling age comes at the cost of highly profitable carcase traits.

Recent research by the NSW Department of Primary Industries (DPI) highlights the impact of having reasonable levels of muscularity in beef females to achieve high levels of muscle and hence meat yield in their progeny.

According to DPI beef industry leader, Bill McKiernan, sire selection alone for carcase traits like muscling achieves little progression in their progeny if not combined with a similar contribution from the female.

'The best muscle bulls in the world, particularly within breed won’t progress carcase traits or ‘beef’ traits if all he has to work with is dairy cattle look-a-likes,'he said.

'Although the use of high muscle bulls on poor or average muscle females produces a response in the first generation, it is not enough to attract premiums in the market place.

'However if the resultant females of higher muscularity are selected to go back into the herd and then mated again to high muscle bulls then the resultant progeny will be sufficiently superior in muscularity to achieve the desired premiums.'

Research results from DPI’s muscle selection lines at Glen Innes clearly demonstrate the effect of muscle selection in second and subsequent generations.

The overall level of muscling and meat yield in the Australian Beef herd has not increased over the last 40 years because beef producers are actively selecting against muscling in females, according to Mr McKiernan.

'Females with the ability to be both productive and add to their calves’ carcase worth are being culled before they even got the chance to demonstrate their contribution,' he said.

'Many producers, when selecting replacement females for their beef herd, place undue emphasis on ill-defined traits like ‘femininity’ and ‘motherability’ when in fact these sort sof traits can be easily measured.

'Femininity or more importantly fertility can be simply measured by allowing heifers access to a bull - what better assessment can be made than if she gets in calf or not,' he said.

'Her future performance can also be measured by her ability to calve naturally and, at the weaning of her first calf, her ability to milk or ‘motherability’ can be assessed against her peers.'

Mr McKiernan suggests over mating the heifers by 10 percent or more in order to allow selection and culling to be made post mating and then again on poor performers based on their calves weaning performance.

Contact: Bill McKiernan,Orange on 02 6391 3431.

This story appears in Agriculture Today.