31 August 2001

High Beef Value bulls do sire better offspring

HIGH Beef Value bulls produce progeny with superior slaughter and carcass weights, compared with lower Beef Value bulls, according to Harper Adams research.

As part of the whole-crop feeding study, the performance of bull and heifer calves, sired by either high BV bull Ronwick Hawk or low BV bull Staveley Hurricane were recorded. Market-bought heifer calves of unknown breeding were included in the study.

"Calves sired by Ronwick Hawk recorded significantly higher carcass weights than both Staveley Hurricane and market-purchased calves," says Simon Marsh (see below).

"The Ronwick Hawk calves also recorded higher daily liveweight gain, slaughter weights, conformation scores and killing out percentage."

Only 25% of heifers out of the high BV sire failed to meet minimum carcass specifications demanded by the abattoir, whereas 62% of the low BV sires missed targets.

Achieving higher weights meant the Ronwick Hawk bull and heifer calves took an extra 4.8 and 15 days, respectively, to reach slaughter condition, compared with the other bulls progeny.

"But taking into account extra feed and increased semen costs, the higher carcass weight meant average economic benefit of using the high BV sire was £17.10 a calf."

Based on the economic evidence, Mr Marsh believes beef producers must use high BV bulls to improve the genetic merit of breeding herds to survive financially.

The market-bought heifer calves performance was similar to the low BV heifers. "This highlights the fact that many dairy producers are not using high genetic beef sires, but are probably more concerned with ease of calving.

"Perhaps if calves sired by high genetic bulls were somehow identifiable at market, dairy producers could receive premiums on their sale value."

Pedigree beef herds should also be recording performance to formulate Estimated Breeding Values for sale bulls in order to achieve market premiums, he adds. &#42

Performance of high v low

beef value in bull progeny

BV 29 BV7

Slaughter wt (kg) 631.6 609.3

Days to slaughter 486.7 481.9

Daily lwt gain (kg) 1.19 1.16

Carcass wt (kg) 358.8 341.6