The Effects of L-Valine Supplementation in Feed on the Growth and Ileal Morphometry of Grower-Phase Native Chickens

The content of essential amino acids in feed affects the growth rate of grower-phase poultry. In this study, the influence of valine amino acid supplementation (L-valine) in feed on the growth performance and ileal morphology of grower-phase native chickens in Kefamenanu, East Nusa Tenggara Province of Indonesia, was observed from July to August 2022. A total of 200 native chickens of 6 weeks of age were divided into 5 treatment groups with 5 replications based on a completely randomized design. The treatment feeds were T0 (control feed), T1 (T0 + 0.60% L-valine), T2 (T0 + 0.85% L-valine), T3 (T0 + 1.10% L-valine), and T4 (T0 + 1.35% L-valine). The highest body weight was observed in the T3 group (1417.00±16.17 g/bird), with a weight gain of 19.34±0.30 g/bird/day. This was significantly different from that of the other treatments (P<0.05). The lowest body weights observed in the T0, T3 and T4 groups were 1372.00±7.42, 1390.40±16.06 and 1386.60±8.73 g/bird, respectively. The lowest weight gain of 18.53±0.16 g/bird/day was observed in the T0 group. The feed consumption for the T0, T1, T2, T3 and T4 groups was 62.54±0.16, 62.79±0.36, 62.93±0.38, 62.69±0.39, and 62.77±0.34 g/bird/day, respectively, but the differences were not significant. A significantly higher feed conversion of 3.25±0.06 (P<0.05) was observed in the T2 group compared to the T0, T3 and T4 groups. Carcass weight and carcass percentage were significantly higher in the T2 group; these values were 883.18±6.74 g/bird and 62.19±0.93%, respectively (P<0.05). This study showed that the villi height, villi width, and crypt depth of the ileum of the T2 group (1036.60±65.67, 274.00±6.32, and 243.80±6.72, respectively) were significantly different from those of the other treatments. It could be concluded that that feed supplementation with 0.60-0.85% L-valine has a positive influence on the growth and ileal morphometry of native grower-phase chickens.