The effect of threonineon mucin2 gene expression,intestinal histology andperformance of broiler chicken

摘要

Threonine needs based on Ross manualsmight be 14% of the National Research Council(NRC) recommendation, thus the effect ofthreonine on mucin2 gene expression, histologicalcharacteristics and performance wereevaluated in Ross male broilers fed diets containing0.8% (NRC requirement), 0.87% (averageof NRC and Ross requirement), 0.94%(Ross requirement) and 1.01% (more thanRoss requirement) total threonine. The dietarytreatments consisted of an isonitrogenouscorn-soybean meal-based diet with incrementallevels of threonine. At the first day of chickenage, 24 pens were equalized to 12 birds perpen, in a completely randomized design anddietary treatments were randomly distributedfor the 14-d period. Live performance measurementsimproved (P<0.05) as dietary threonineincreased from 0.8% to 0.87%. The least performancewas related to diet containing 1.01%threonine. Histological assays showed that villiheight, crypt depth and villi surface increasedas dietary threonine increased from 0.8% to0.87% and decreased in 0.94% and 1.01% threonine.There was no effect of threonine onmucin2 gene expression and goblet cells density.According to these results, threonineneeds in starter period in Ross (308) broilersis more than NRC recommendation.