‘Shift pig focus from litter size to viability’

A shift in focus from litter size to improving management in the farrowing environment would improve piglet viability and, therefore, prospective profit, producers have been told.

Emma Baxter, behavioural scientist at the Scottish Agricultural College (SAC), told delegates at the recent BPEX piglet survival workshop, Pocklington, Yorkshire, too much focus on litter size was not healthy for producers or piglets. “Survival at five-day-old or numbers weaned is a more important benchmark,” she said.

A balance between long-term and short-term management strategies would increase piglet viability. “While boars influence birthweight, don’t select sows on just numbers born. Udder and teat quality are important for getting infant piglets through the first few critical days of life.”

Equally the farrowing environment was key, suggested Dr Baxter. “Despite domestication, a sow needs to display nesting as functional behaviour before farrowing. Providing a substrate – straw, chippings or hessian rope tied to bars – helps.”

Allowing first time gilts to physically see other gilts and sows in farrowing areas helped reduce stresses, she explained. This helps reduce the shock of farrowing for the first time and increasing the likelihood of piglets being accepted, producers heard.

“Piglets have little brown fat or body glycogen – forms of energy – when born, increasing the importance of getting the sow’s colostrum in the first few crucial hours,” explained Dr Baxter. This also provided most of the piglet’s antibodies to help fight infection.

Producers should ensure those piglets born at night – or out of sight of staff – got a good feed. Sows release colostrum for 12 hours post-farrowing allowing cross fostering smaller piglets for short periods. “But by three days old the piglet’s gut wall can no longer absorb colostrum,” explained Dr Baxter.

Providing bedding, preferably straw for moisture absorption, was recommended. Piglet body temperature can plummet from 37.2C to 31C as placenta fluid evaporates sapping body heat. Using heat lamps or pads would increase survival rates, as would ensuring good drainage of the farrowing area, she added.

Where sows are induced (to farrow) staff must remain vigilant to avoid a “pile up” of new-borns and ensure piglets get to suckle quickly. Producers were surprised to hear 10% of piglets – similar to the level of still-births experienced on-farm – are born with the placenta chord broken, increasing risks of oxygen starvation. “Be vigilant,” she added.

Development of larger, welfare-orientated farrowing pens may improve piglet survivability. At SAC PigSAFE (Piglet and sow alternative farrowing environment) pens have sloped barriers suspended away from floor level in sow lying areas, allowing piglets to escape from mothers.

Piglet creep areas are provided with narrowly spaced bars preventing sows/gilts from entering. “These are still under development and have another year of testing in a current DEFRA-funded trial. Cost will be about 25-50% higher than conventional farrowing pens,” explained Dr Baxter.

While producers debated the merits of indoor and outdoor farrowing methods, MLC pig yearbook data from 2001-07 suggested there was little difference between the two systems when looking at numbers weaned a sow (9.71 v 9.64, respectively). “Any progress towards a more natural environment for the sow is likely to improve piglet survival,” added Dr Baxter.

No single action will improve universally piglet viability, she said. Breeding, management of both sow and litter, and post-farrowing care were all important. “Keep records of dam performance, particularly gilts,” she advised.

Producers should not be seduced by breeding stock offering large litter size. “It is better to have 10-12 viable piglets than larger litters. Invariably, larger litters are likely to incur smaller piglet size increasing vulnerability.”

Farrowing performance (MLC YEARBOOK AV. 2001-07)