Impacts of birthweight and pre-natal growth restriction on piglets

Larger litter size from prolific sows has reduced birth weight of commercial pigs and lead to increased variation of birth weights within a litter. However birth weight alone does not distinguish between small piglets and those that have experienced intra-uterine growth restriction (IUGR).

PROHEALTH work in the UK has been studying IUGR piglets on a JSR Genetics commercial farm to try and understand the impact of these animals and possible strategies to reduce their occurrence in future generations.

A significant benefit to JSR Genetics of participation in the project was the increased level of data recording that was instigated on the farm where the work was carried out, with records being taken on over 1,500 farrowing and 21,000 piglets which included individual birth weight, head shape and full survival records or cause of death. In addition to the planned findings of the research, these data provided useful information to inform JSR about best practices on this and other farm(s).

The farm contained various farrowing house designs and, during the one year project, implemented different management practices. The data collected at a piglet level, rather than simply at a sow farrowing level, meant optimal farrowing house design could be identified and could better determine the impact, both positive and negative, of a specific management practice. These data could be analysed to remove any seasonal or genetic effects and be used to further influence future decisions on the farm.

The work highlighted that selecting at sow level against IUGR could be a beneficial tool to improve piglet survival and was much more heritable than selecting on piglet survival alone. Furthermore, discussions internally and with JSR Genetics partners on these findings have encouraged the business to do more to understand IUGR causes. This has included the opportunity to look at spacing between embryo implantation sites within the uterus which may also be influenced by the genetics of the sow.

Therefore, whilst the direct benefits of the project have given opportunities to further develop the selection strategy of sows, it has also created new ideas and areas to explore. The additional benefits from the detailed data made available have been of added value to further improve pig production at JSR Genetics.