The Study Of Methionine Requirement In Piglets

This experiment was mainly according to study the impact of different methionine levels diets on production performance, apparent digestibility of nutrients, blood physiological and biochemical indicators in piglets to determine the appropriate methionine requirement.It was designed by randomized trial of single factor, selecting36crossbred piglets (DLY)with the same origin, healthy and the similar weight at23.26±0.48kg which were randomly divided into6groups(3replicates per group,2piglets per replicate).6groups of piglets were fed with different methionine levels diets (0.18%,0.24%,0.30%,0.36%,0.42%,0.48%) in their7d pre-feeding and28d feeding. Fasting weighing the piglets in the morning at the test of1st d,15st d and29st d, then investigated respectively the daily gain, average daily feed intake and feed conversion of piglets in their fist2weeks, later2weeks and the whole period.Collected piglets fecal samples of each group at the end of experiment and tested the apparent digestibility of energy, crude protein and methionine. After feeding trial, selected a healthy piglet each repeat to collet the blood from their anterior vena cava for determining the blood biochemical parameters (TP, ALB, UREA, GLU)and blood hormone index (GH, Ins, IGF-1). The results are as follows:1Different methionine levels diets had a significant effect on the performance of piglets in their fist2weeks, later2weeks and the whole period(.P<0.05). There was a strong quadratic curve relationship between performance indicators and methionine levels, which meaned average daily gain, feed efficiency, average daily feed intake firstly increased and then decreased with the increasing methionine. when the methionine level was0.30%, the performance of piglets were best.2The apparent digestibility of dietary nutrient was also significantly effected by different methionine levels diets(P<0.05). The apparent utilization of dietary energy, crude protein and methionine in piglets showed a quadratic curve variation with increasing firstly and then decreasing as the increasing methionine levels. The apparent digestibility of energy and methionine was highest at0.24%Met, which was significantly higher than any other groups (P <0.05); The apparent digestibility of crude protein was same higher at0.30%Met as well as0.24%Met than other four groups (P<0.05).3Different methionine levels diets had a significant effect on part of blood physiological and biochemical indexes in piglets(P<0.05). Total protein, albumin and IGF-Ⅰreached maximum when the methionine level was0.24%, and they had a conic change trend with increasing firstly and then decreasing as methionine level increased. While Urea was firstly decreased and then increased with methionine level elevated, and it reached a minimum at0.24%Met.Different methionine levels diets had no significant effect on blood glucose, insulin and GH(P>0.05).