Pig production faces mounting economic and environmental pressures. A study from French researchers shows that efficiency alone does not guarantee reduced environmental footprints. By simulating individual pig performances, the team found that amino acid requirements and protein deposition potential are equally critical in shaping outcomes.
Individual-based modeling reveals hidden differences
Traditional assessments often evaluate groups of pigs fed diets covering average nutritional needs. This approach masks individual variability, leading to overfeeding or underfeeding. The study instead applied an individual-based model, using growth data from 732 Large White males. Each pig’s profile generated a virtual population of 1,000 animals, allowing simulations of technical, economic, and environmental performances.
The model incorporated feed formulation, growth simulation, and life cycle assessment. It accounted for feed production, transport, housing, and manure management, ensuring impacts were measured from cradle to farm gate. This comprehensive approach revealed how individual traits influence both emissions and resource use.
Feed efficiency is not the only driver
Results showed three distinct clusters of pigs. Cluster 1 displayed the strongest environmental and economic outcomes, marked by low feed conversion ratios, relatively low‑impact feeds, and high protein deposition potential. In contrast, Cluster 2 showed the least demanding amino acid requirements but struggled with inefficiency, leading to weaker overall performance. Meanwhile, Cluster 3 matched Cluster 1 in feed efficiency yet relied on high‑impact feeds due to elevated amino acid needs, which ultimately produced worse environmental scores.
The findings highlight that pigs with similar feed efficiency can differ sharply in environmental impact depending on their nutritional demands. This challenges the assumption that efficiency alone is a reliable marker of sustainability.
Key traits shaping environmental performance
The analysis identified three main factors: feed efficiency, amino acid requirements at the start of fattening, and protein deposition potential. While feed efficiency remains important, it cannot alone identify pigs with the lowest impacts. Accounting for amino acid needs and deposition potential is essential to reduce emissions and resource use.
The study also showed that pigs with high amino acid requirements often relied on more impactful feed ingredients, increasing climate change and eutrophication scores. Conversely, pigs with lower requirements consumed less intensive feeds but grew less efficiently, raising costs and emissions per kilogram of weight gain.
Implications for pig production systems
The findings challenge the assumption that selecting pigs based solely on efficiency will lower environmental footprints. Instead, a broader view of animal traits is needed. By integrating individual requirements into feeding strategies, producers can better balance economic returns with sustainability goals.
This approach could reshape breeding and management practices, ensuring that environmental impacts are fairly assessed and reduced. As the authors note, “feed efficiency alone cannot be retained to identify pigs with the lowest impacts.” Considering amino acid needs and protein deposition potential alongside efficiency offers a clearer path toward sustainable pig production.