Grass-based feeding strategies for organic growing-finishing pigs during temperate summer conditions.

Summary in the original language of the document

This study assessed the substitution of soy press cake with Green protein, derived from biorefining of grass-clover, and the provision of grass-clover-based roughage for organic growing-finishing pigs under temperate summer conditions. A total of 150 pigs were assigned to five dietary treatments combining soy or Green protein concentrates with fresh grass-clover or silage. Growth performance, feed intake, lean meat percentage, and blood metabolite levels were measured.
Substituting soy with Green protein did not adversely affect growth performance. Feed efficiency was superior in soy-based dietary treatments compared to Green protein with silage allocation when expressed as metabolisable energy (ME)/kg gain. Lean meat percentage was higher in pigs fed Green protein and fresh grass-clover than in those fed soy with silage. Roughage intake was greater when allocated as fresh grass-clover compared to silage, and fresh grass-clover provided more nitrogen to the animals than silage. Reducing lysine levels by 10% in the Green protein concentrate concurrent with fresh grass-clover allocation did not compromise productivity but increased lean meat percentage compared to pigs fed soy with silage. Dietary treatment had only minor effects on blood metabolite levels.
In conclusion, Green protein can effectively replace soy in organic pig concentrates without adversely affecting performance. Substitution resulted in a higher lean meat percentage, suggesting that Green protein possesses a more favourable amino acid profile for growth than soy protein. Green protein represents a promising alternative for the organic pig sector, with fresh grass-clover providing additional nutrients and enabling a reduction in protein levels in concentrate feed.