Ås – Norway
Sustainability of pig production on rapeseed meal
The European pig industry is heavily dependent on imported feed ingredients, especially soybean meal as a protein source in commercial diets. Increased and more efficient use of local protein sources, such as rapeseed, could improve the sustainability and self-sufficiency of pig production in Europe. Use of rapeseed meal in pig diets is, however, associated with reduced feed intake, growth rate, and nutrient utilization due to the high dietary fiber content and the presence of several anti-nutritional factors such as glucosinolates.
Systematic selection for reduced feed intake per kg gain made the Norwegian Landrace pig a fast growing and highly efficient breed. However, efficient pigs have been selected based on growth rate when fed high-quality cereal, soybean meal based diets with moderate fiber content. In the FeedMileage project, which is the spring board project to the SusPig project, we aim to evaluate how efficient pigs are when fed local fiber-rich rapeseed meal-based diets.
We observed a large variation in how the pigs utilized the feed – some pigs performed well while others performed less – and we want to know why. Was this due to individual differences in digestive capacity? Did pigs that show variation in performance have different gut microbiota profiles? Or were they more efficient in metabolizing the absorbed energy and nutrients?
To answer these questions, we performed several experiments where pigs were fed a soybean meal based diet versus a diet containing high levels of rapeseed meal. Large individual variation in traits influencing feed efficiency was found. For instance, we observed large differences in pig’s ability to digest nutrients, especially fiber, when fed high-fiber rapeseed meal diets versus standard cereal and soybean meal based diets.
We are currently performing several analyses to get a better understanding of why pigs performed differently, including gene expression of gut, muscle and liver tissues; gut microbiota profiling, activity of digestive enzymes in the gut; metabolomics profiling of intestinal contents and liver, and activity of hormones regulating appetite and thyroid function. We also SNP genotyped the pigs to connect specific phenotypes with known genotypes to estimate their effects and to predict breeding values. The results will help us identify novel phenotypes associated with feed efficiency traits and potential biomarkers with key physiological roles explaining the observed individual differences that can be used in future breeding programs. By doing so, we hope to bridge the gap between the genotype and the phenotype to better understand the biology behind feed efficiency and help adapt pigs to local feeds.
– Margareth Øverland
– Hanne Fjerdingby Olsen
– Adrijana Skugor
– Liv Torunn Mydland
– Gunnar Klemetsdal
– Theo Meuwissen
– Peer Berg