Effect of l-arginine and l-lysine supplementation in low-protein feeds on the growth of native chickens in the starter phase

Some feeds that are used as protein sources, such as fish meal and soybean meal, have a relatively high cost. Therefore, synthetic amino acids, such as arginine and lysine, can be used as alternative protein sources. This study determined the effect of L-arginine and L-lysine in low-protein feed on the growth of one- to six-week-old native chickens. A total of 250 one-week-old native chickens were divided into five treatments and five replications based on a completely randomized design. The treatments were T-2 (0.46% L-arginine + 0.42% L-lysine + 19% crude protein), T-1 (0.56% L-arginine + 0.51% L-lysine + 18% crude protein), T0 (0.66% L-arginine + 0.60% L-lysine + 17% crude protein), T+1 (0.76% L-arginine + 0.69% L-lysine + 16% crude protein), and T+2 (0.86% L-arginine + 0.78% L-lysine + 15% crude protein). The highest feed consumption occurred in the T0 and T+1 treatments (612.81±4.82 and 609.00±8.75 g/chick), and the T+1 group had the highest body weight and weight gain (296.08±1.09 kg/chick and 265.48±1.57 g/chick). The highest carcass weight and percentage at T+1 was 177.57±2.04 g/chick and 59.97±0.55%/chick, respectively. The best feed conversion was at T+1 (2.29±0.40). Statistical analysis showed that the treatment had a significant effect on feed consumption, body weight, weight gain, feed conversion, carcass weight, and carcass weight percentage (P<0.05). The levels of 0.76% arginine + 0.69% lysine increased the feed consumption, weight gain, feed conversion, and carcass percentage of native chickens. The increase in L-arginine and L-lysine of 0.76 and 0.69% from 0.46 and 0.42%, respectively, suppressed the use of crude protein by 19.00% to 16.00% in the starter phase.