Balancing compound lysine level and roughage intake: impacts on performance and protein utilisation in organic growing-finishing pigs

Summary

Organic pigs must meet lysine needs without synthetic amino acids, making crude protein management challenging. In this study, varying lysine levels in compound feed had little effect on growth, though lower lysine reduced early‑phase feed efficiency and lean meat percentage. Roughage intake was high but contributed only modest amounts of usable protein. Higher lysine increased metabolic nitrogen turnover without improving productivity. Optimal lysine supply should therefore balance feed costs, nitrogen efficiency and carcass quality, recognising that grass‑clover silage only supports amino acid supply when forage quality is high.