Relationship between feed, genetics, health, and growth performance up to market weight in pigs - Ontario Pork - Active Research
Thursday, September 28, 2023

Active Research

Ontario Pork has a call for research proposals once a year. These projects were approved for funding by the board on recommendation of the research committee. If you have questions or need further information about the research posted here please contact Jessica Fox at

Active Research

Relationship between feed, genetics, health, and growth performance up to market weight in pigs

Project 15-015 - Brandon Lillie, University of Guelph

Researchers: Brandon Lillie and Vahab Farzan, University of Guelph
Graduate students: Corinne Schut, MSc (current), Elana Raaphorst, MSc (current), Margaret Ainslie, MSc (graduated), Heather Reinhardt, MSc (graduated)

Reduction of the pig production through novel feeding strategies is currently an active research topic.  A study by Kees de Lange that was conducted under controlled conditions at the University of Guelph’s Arkell Research Station, indicated that lower-cost, reduced animal-protein diets, can be fed to nursery pigs without any negative impact on subsequent performance as long as pigs do not become diseased. Based on these findings, a University of Guelph research team is now testing the impact of feed quality and health on pig growth performance under commercial farming conditions. In addition, the research group will investigate the immune status and genotype of pigs that remained healthy or became sick during the trial, in an attempt to determine the genetics of pigs that are resilient to disease challenges. Eight farrow to finish farms are participating in the three year study.  At weaning, pigs will be assigned to either a reduced animal-protein or a conventional nursery feeding program. The pigs will be weighed five times throughout the trial from birth through to the finishing stage.  Pigs will be monitored for occurrence of diseases, and sick pigs will be submitted to Animal Health Laboratory for diagnosis. At slaughter a subset of pigs will be evaluated for carcass dressing percentage and lean yield. Blood and fecal samples as well as nasal swabs will be collected and tested for presence of several swine diseases including PRRS, influenza and salmonella. 

Project Results to date: Overall, feeding a lower-cost, reduced protein nursery diets did not have a negative effect on pig growth performance.  Carcass quality traits (HDW, loin eye depth, back fat depth, percent lean yield) and carcass value were also not influenced by nursery diet complexity. Reducing nursery diet complexity may be a feasible alternative to help reduce the cost of pork production (an estimated savings of $2.82 per pig).   However pigs fed the low complexity diet had a greater tendency to shed Salmonella shedding over the production period (p=0.06). Further investigation into this relationship and the impact of genotype on health and/or response to diet are in progress.

Further reading: (pg 40)