Gordon McKen fears pressure from animal-rights groups will lead to future problems with loose farrowing systems that could end up with more piglets being killed by their mothers and the creation of a new welfare issue.

Mr McKen, speaking at the Scottish Agricultural College’s pig health event in Edinburgh, said a full debate was required so that any decision is made on the best scientific evidence.

He added: “Confinement of the sow in a farrowing crate is an issue facing us. The problem is the debate is being influenced by some people with no practical experience of the sector. The purpose of confining sows is that it saves piglets’ lives, allows for sow management and protects stockspeople.”

The plea from Mr McKen, the managing director of Huntly-based Scottish Pig Producers, stems from changes being made to production systems elsewhere in Europe and the RSPCA’s Freedom Foods label which has, since 23 January, prevented the use of farrowing crates by any new producer signing up to it. Existing producers can still use the crates for up to five days after piglets are born up to the end of 2013.

SAC research scientist, Emma Baxter, said there was increasing pressure by animal-welfare groups to force changes, according to The Press and Journal. They were “naming and shaming” retailers sourcing pigmeat from indoor farrowing crate systems. The problem does not exist outdoors as sows build nests.

Sweden is the only EU country where farrowing crates are not allowed. It, however, has a concession that allows problem sows to be constrained in crates for the first few days after they give birth.

Ms Baxter said the European Food Safety Authority had concerns about crates as they were detrimental to movement and did not allow sows to naturally build a nest before farrowing. But it also said loose farrowing should only be implemented if piglet mortality is no greater.

She said various studies were ongoing to find the best alternative system to avoid the welfare problems created by sows crushing their piglets or attacking them.

Mr McKen said scientists and producers had to be given time to find the best regime. His concern was that retailers would respond to the animal rights groups and do their own thing without thinking of the implications on producers. “My real fear is that we get bulldozed into something that does not work,” he added.

Ms Baxter said SAC was also undertaking work aimed at preventing pre-weaning mortality and stillbirths. An average of two piglets in every litter die before weaning. Across the UK, it is estimated that equates to two million deaths at an annual cost to industry of between £72 to £92 million. The main causes are disease, starvation, sows lying on their offspring and piglets becoming chilled after birth.

Ms Baxter said achieving more even litter sizes may address the issue. That would mean making sure sows received optimum nutrition during gestation and lactation. Research had shown piglets that reached udders quickly were more likely to survive, while sows under stress savaged their piglets.

Genetic selection might help too. SAC animal behaviour expert, Simon Turner, said genetics could also assist reduce pig aggression.

A study on the use of peas and beans as an alternative feed to imported soya is continuing. A survey has found support, but it has highlighted concerns about the availability of both products in sufficient quantities.