Early scans can ID fat sheep

“There is a very strong correlation between young and older animals for fat, and this is the same for muscle and weight,” says University of Adelaide researcher Sam Walkom.

“For producers, this means that selection for improved condition score in the young breeding ewe can be useful.”

Walkom’s work was supported by Australia’s Sheep CRC and investigated the potential to breed lines better able to maintain condition in tough times through adaption of fat reserves.

He found superior genetics could indeed be an “insurance policy”, especially when managing pregnant ewes.

“Having sheep with superior genetics for fat storage gives producers more flexibility in their management, for example being able to delay supplementary feeding because individuals will have more condition when entering tough times,” he suggests.

Management of feed is still paramount to maintaining condition of ewes, but Walkom says genetics may be used to provide an “edge” in many breeds and environments.

“Across all breeds and sites our results were very similar with differences in the genetics for weight, fat, muscle and condition remaining constant; meaning that ewes will maintain their genetic superiority for body composition traits during tough times providing the potential to hold off supplementary feeding for longer.

“This is gives producers a better chance of getting more lambs on the ground in good condition and maintaining or improving their weaning rates.”

However, the benefit of breeding sheep for increased fatness may be of limited value in areas that have high certainty of good feed conditions, he adds.

“In production systems where there is reliable pasture production, breeding programs can focus on traits that will have more impact on profit such as growth and reproductive performance – it is therefore important that every producer should be selecting for fat that matches their particular management and production systems.”