Peter Shelton, European managing sales director for JSR Genetics points out that due to the strong trade, cull sows have been making well over £100 per head. "This goes a long way towards the cost of a genetically-improved replacement gilt," he said.

"During the foot-and-mouth disease restrictions, many units used what they had to maintain production, including old sows, cull sows and gilts out of the fattening house. All this seemed better than nothing at the time but, with the industry currently averaging only 17.5 pigs sold per sow per year, clearly this is not acceptable today."

To maximise herd performance the average parity should be close to three. "Inevitably, the old sow lets you down in terms of numbers born and an empty farrowing pen is even worse."

Peter Shelton points to the fact that younger animals are much more productive. "Some units have improved performance over the last few months and these largely appear to be those with younger herds. Several JSR-owned herds are exceeding 28 pigs born alive per sow a year and weaning over 26 strong, viable pigs," he said.

Source: JSR Genetics - 30th November 2004