Lysine requirement for growing-finishing immunocastrated male pigs

Abstract

Eighty boars (19.3 ± 2.49 kg) were vaccinated twice (100 and 128 days of age) against gonadotropin releasing hormone (Vivax™ vaccine), for a randomised block design study aiming to evaluate five digestible lysine (DLys) level treatments, with three phase-feeding per treatments (9-8-7; 10-9-8; 11-10-9; 12-11-10 and 13-12-11 g/kg) during the growing-finishing phases (54-100, 100-128 and 128-155 days of age, respectively). Pigs were fed their respective diets ad libitum from 54 to 155 days and weighed at 100, 128 and 155 days. Pig loin (Longissimus dorsi) area, loin depth and backfat thickness were measured by ultrasound at 100 and 155 days. Hot carcass weight, meat quantity and meat yield were measured at slaughter. From 54 to 100 days (pre-immunocastration), DLys levels linearly improved pig feed conversion and loin area, the level of DLys for minimum feed conversion and maximum loin area was 13 g/kg. However, DLys levels had no effect on the performance of boars from 54 to 128 days (pre-immunocastration), nor on the performance and carcass parameters of immunocastrated male pigs between 54 and 155 days. A sequence of diets containing 9, 8 and 7 g/kg of DLys fed from 54 to 100, 100 to 128 and 128 to 155 days, respectively, meet the requirement of growing-finishing immunocastrated male pigs.

Effects of Dietary Lysine Levels on Growth Performance, Nutrient Digestibility, Serum Metabolites, and Meat Quality of Baqing Pigs

“…The present study aimed to determine the response of pigs from the Chinese indigenous genotype to variables in the SID Lys level from 20 to 90 kg bodyweight and therefore estimate the optimal dietary SID Lys requirements of Baqing pigs at growth-finishing periods. Previous studies have clarified that Lys supplementation in the basal diet improved the growth performance and nutrient digestibility of growing and finishing pigs [ 24 , 25 ]. Similarly, Oresanya et al [ 26 ] illustrated that the BW and ADG of weaned pigs increased quadratically with increasing dietary Lys concentration.…”