19 May 1995

Profitable pigs greedier young

PIG producers could gain an extra £5 a pig by matching the nutritional needs of finishing pigs to genetic potential for lean growth.

Evidence comes from a Cotswold Pig Development Company trial to determine genetic potential for lean growth and appetite.

Results revealed that lean tissue growth rate could exceed 370g/day between 20-40kg liveweight, increasing to a maximum of 520g/day at 80kg lw. After that stage the pig was likely to eat too much in relation to lean growth potential and get fat.

"In the early stages of growth appetite, rather than lean growth potential, can be limiting, but later on pigs may eat too much and become fat," said Cotswold geneticist Dr John Webb.

He suggested greedy pigs may be the most profitable if they grow lean faster. "The aim is to select those pigs which eat more early in their lives, when they convert feed into muscle most efficiently, and have the genetic potential to convert the extra feed to lean tissue."

Cotswold nutritionist Felicity Jones said the trial results highlighted the need to change diets at more stages throughout the finishing stage to balance daily nutrient intake with requirement for lean gain. The benefit would be faster growth, a higher feed conversion ratio and better grading.

"Feeding one finisher feed will fail to maximise efficiency because the type of feed needed by a 50kg pig is different to that required for a 95kg pig," she said.

&#8226 Some 280 pigs were fed ad-lib with intake recorded through Cotswold Hunday electronic equipment. Pigs slaughtered at six stages from 20-120kg liveweight were dissected at Bristol University to determine lean tissue and fat content.