Effects of dietary lysine intake on performance, organ weights and carcass characteristics of post-weaned Iberian piglets

The present work is part of an experimental program aimed to establish the dietary lysine (Lys) requirements of post-weaned Iberian piglets. For this purpose, we used 66 castrated male Iberian piglets of Silvela strain, with approximately 10 kg bodyweight and 40 days of age. Piglets were fed one of six experimental diets differing in their dietary Lys content. L-Lys was added in increasing concentrations (from 55 to 80 g Lys/kg crude protein) to a basal diet containing corn, barley and soybean meal, at the expense of corn starch. The supply of nutrients, as amino acids (other than Lys) and energy, met or exceeded the current recommendations for piglets. Piglets were fed twice daily ad libitum. The average daily feed intake were not affected by Lys supply (ADFI, 873 g dry matter/d, as average value; P>0.05). Both, daily gain (ADG, g/d) and gain-to-feed ratio (ADG:ADFI) were significantly affected by the Lys level (P