Arginine requirement of breeding pigeons during incubation and lactation in the 2 + 4 lactation pattern

1. This study evaluated the effectiveness of different concentrations of arginine (Arg) in the diet on reproductive performance, body weight loss and plasma biochemical indices of breeding pigeons as well as on growth performance, carcass characteristics and plasma biochemical indices of squabs.2. In total, 360 pairs of 12-16-month-old European Mimas breeding pigeons were randomly divided into six groups (10 replicates of 6 pairs each). They were fed different pelleted diets with Arg levels of 0.58, 0.73, 0.88, 1.03%, 1.18 or 1.33%, respectively, for an experimental period of 45 d.3. The highest body weight gain during the incubation period occurred in the 1.03% Arg group. Feed intake increased curvilinearly throughout the trial in line with the increase in Arg levels, the highest being observed in the 1.18% Arg group.4. Body weight of squabs increased curvilinearly with an increase in Arg levels, with the highest occurring in the 1.18% Arg group. The FCR decreased curvilinearly with an increase in Arg levels. The lowest FCR occurred in the 1.03% and 1.18% Arg groups. Slaughter weights, eviscerated weight and pectoral muscle weights of 21 d squabs increased curvilinearly with increasing Arg levels and the best slaughter yield was observed in the 1.18% group.5. In addition, the highest plasma activities of total superoxide dismutase (T-SOD) and catalase (CAT) and the lowest malondialdehyde (MDA), aspartate transaminase (AST) and uric acid (UA) levels were observed in the 1.18% group. Using binary regression modelling in SPSS, the optimal dietary Arg level for breeding pigeons, based on the slaughter performance and FCR of squabs was 1.01-1.07%. Additionally, based on the full-term weight loss and oxidative stress of breeding pigeons as evaluation indexes, 0.96-1.01% Arg was optimal.6. In conclusion, the optimal dietary Arg for the best reproductive of breeding pigeons and growth performance of squabs in a 2+4 lactation pattern was 0.96%-1.07%.