Effect of dietary choline on performance and body composition of broiler chichen in the tropics [Sudan]

Two experiments were conducted concurrently to assess the effect of dietary choline on broiler chicks performance in the tropics. In experiment I, four experimental diets were formulated condtaining graded levels of choline (0.0, 0.130 and 0.195) with L-lysine and DL-methionine being added to the diets to reach the recommended levels for broiler chicks. In experiment II, similar incresing graded levels of choline were maint-ained without DL-methionine being supplemented. 400 Bovan broiler chicks were equally allocated into 40 pens (10 chicks/pen and 20 pen/ experiment). Then the experimental diets were randomly assigned to the pens.feed and water were provided ad libitum in both experiments plus 24 h photo-period was maintained throughout the 4 weeks experimental period. In experiment I, the results obtained showed that feeding graded levels of choline under normal methionine level caused a linear increase in both feed intake (P0.01) and body weight gain (P0.05). And it resulted in insignificant effect in feed gain ratio (P0.05). However, in experiment II, feeding graded levels of choline under suboptimal methionine levels showed that cumulative feed intake had alinear and quadratic (P0.05) positive responses, and both weight gain and feed gain ratio showed insignificant responses (P0.05) to the dietary treatment. In both experiments I and II, feeding of increasing choline levels with or without adequate methionine have resulted in a linear decreasing effect (P0.05) on mortality rate. These experiments has shown that feeding increasing level of choline under normal methionine level improves broiler performance, while higher choline levels under low methionine depress growth and improve percentage of survival without significant effect on carcass moisture, crude protein, Ash and fat contents.