Effects of Lysine Supplemented on Growth and Nutrient Digestibility of Noi Chickens From 1 to 56 Days Old

Abstract

A total of 256 one-day-old chicks were allocated into a completely randomized design with 4 treatments and 4replicates to evaluate growth, feed conversion ratio (FCR), and nutrient digestibility (ND) of Noi chickens. The treatments consisted of control diets (Lys0) containing 1.0 and 0.9% lysine for birds 1 to 28 and 29 to 56 daysof age respectively; 3 other treatments (Lys1; Lys2; Lys3) had 0.1, 0.2, 0.3% of lysine added to diets respectively. Dietary crude protein (CP) was calculated to 19% and 17% for 1 to 28 and 29 to 56 days old, but dietary ME was2.900 kcal/kg of feed for the entire duration of the study. On the last seven days of each period, one male and one female per replicate were selected to be assessed for apparent ND by ferric oxide (Fe2O3) marker. Birds were fed, provided fresh water ad libitum, and vaccinated to prevent some common diseases. Results showed that lysine supplemented 0.2 to 0.3% and 0.3% in diets for the birds between 1 to 28 and 29 to 56 days old significantly improved the growth and FCR of the chickens (P<0.05). Also, an additional 0.1-0.3% of lysine in the Noi chickens’ diets dramatically increased CP and average amino acid apparent digestibility (P<0.05),but did not effect the calcium and phosphorus digestibility of the Noi broilers.