Both stockmen and industry researchers are in agreement that a combination of cross-fostering and colostrum hold the key to reducing piglet mortality.

According to Dr Sylvaine Boulot of the French Institute for the pig industry, over half of piglet deaths occur on farrowing day and in excess of 85 per cent are recorded in the first week on French farms.

Using data from applied studies on real farms, Dr Boulot told the Breed+3 audience that French units are benchmarked on having below 20 per cent mortality and recording 14 piglets at farrowing.

But, large litters are not the answer, they are just the start, she explained. Each piglet needs a minimum of 200g of colostrum to survive, and the bigger the litter, the greater the challenge.

“As litter sizes increase, total production of colostrum does not change,” said Dr Boulot.

Furthermore, colostrum quality reduces rapidly, meaning piglets have a limited time to receive immunoglobulins. For this reason, cross-fostering must not be done too early, added Dr Boulot.

This is to ensure immunity is transferred to the entire litter before sizing up piglets according to sows.

She also outlined the importance of the environment, arguing the case for regulated heatlamps and providing covers for slatted floors during cold months. Two to three regulated heat lamps were recommended for the first one to three days.

Above all, Dr Boulot stressed the need for good stockmanship and observation in the farrowing house, concluding that weak piglets and supernumerary piglets require specific care.

This is not lost on David Wedgewood of J.C. Lister Farms Ltd, head pig man at Leppington Grange Farm, North Yorkshire.

Together, the farms run 3,000 sows, taking all progeny to bacon weight. David has weaned 30 piglets per sow per year for over two and a half years.

Cross or ‘shunt’ fostering is done for high numbers and thin pigs, he explained. Doing so means piglets are sized up from the start.

This entails moving smaller piglets onto a sow with adequate-sized teats and bigger piglets onto suitable sows that can accommodate them.

David explained that shunt fostering is the key to keeping mortality low and can also facilitate in sow colostrum production.

“We meticulously check litters when they have just farrowed and if we see one or two piglets running off, we put them in a barrow,” said David.

“Once I have a barrow full of piglets I think should be on a different sow, I transfer the piglets to a smaller sow with smaller teats that has a strong litter on her.”

Big piglets are replaced with little piglets and vice versa, meaning that weak animals are taken care of.

“What this does is keep sows udder going and also keeps piglets alive,” added David.

There are setbacks to fostering so many piglets - weaning weight is hit. However, the team is confident that the benefits of cross fostering outweigh the setbacks.

He said the figures on the farm are the product of constantly reviewing methods and addressing errors.

“If we didn’t do shunt fosters like we do, I am sure we would lose a lot more piglets,” concluded David.