Effects of Citric Acid on Growth Performance and Nutrient Retention of Broiler Chicken Fed Diets Having Two Levels of Non-Phytate Phosphorus and Rice Bran

摘要

Citric acid has been reported to increase utilization efficiency of dietary phytate-bound phosphorus and protein. Objective of this study was to determine the effects of citric acid on growth performance and nutrient retention of broiler chickens fed diets having two levels of non-phytate phosphorus and rice bran. Giving a completely randomize design in 2 × 2 × 2 factorial arrangement, 144 broiler chicks in 48 pens received one of the eight experimental diets containing two levels of dietary rice bran (20% or 30%), citric acid (0% or 2%) and non-phytate phosphorus (0.25% or 0.35%) ad libitum from day 21 to 42. Retention of nitrogen, phosphorus, mineral and dry matter was determined using a total collection trial. Feed intake, weight gain, feed conversion ratio and weights of feather, liver, gizzard and pancreas were not significantly (P>0.05) affected by the levels of dietary rice bran, citric acid, or non-phytate phosphorus levels. Retention of nitrogen, phosphorus or dry matter were not significantly affected (P>0.05) by the levels of dietary rice bran, citric acid, non-phytate phosphorus or their interactions. 2% citric acid improved the retention of mineral with 30% rice bran compared to diets with 20% of rice bran. There was no significant difference (P>0.05) in tibia ash when diet contained 20% or 30% rice bran. A significantly (P<0.05) higher tibia ash content was observed when diets had 2% of citric acid with 0.35% of non-phytate phosphorus. It is concluded that 30% rice bran had no adverse effects on growth performance of broiler chicken from day 21 to 42. 2% citric acid produces no beneficial effects at dietary rice bran levels of 20 or 30% or non-phytate phosphorus levels of 0.25 or 0.35%.