Dietary choline requirement of juvenile grass shrimp (Penaeus monodon)

A feeding trial was conducted to determine the dietary choline requirement of juvenile grass shrimp, Penaeus monodon. Purified basal diets were formul ated using vitamin-free casein (containing 370 mg choline per kg) as the pr otein source. Graded levels (0, 300, 600, 1000, 2000, 4000, 7000, and 10000 mg choline per kg diet) of choline chloride were added to the basal diet, resulting in eight dietary treatments in the experiment. Each diet was give n to three replicate groups of shrimp initially averaging 1.18 (s.d. 0.01)g for 8 weeks. Weight gain was highest in shrimp given the diets supplemente d with 7000 anti 4000 mg choline per kg diel, followed by the groups given 2000 mg/kg, then 1000 and 600 mg/kg, and finally 300 mg/kg and the unsupple mented control group (P < 0.05), Shrimp given diets supplemented with 7000 and 4000 mg choline per kg dirt had significantly higher food efficiency an d survival than those given diet with 300 mg choline per kg or the control dirt. Higher body crude protein choline concentrations were recorded in shr imp given dirts supplemented with 4000 and 7000 mg choline per kg diet than shrimp given diets with less than or equal to 600mg choline/kg and less th an or equal to 2000 mg choline per kg, respectively Analysis by polynomial regression of weight gain and body choline concentration for P. monodon gav e a maximum at about 6000 mg/kg. Taking into account the choline concentrat ion of the unsupplemented basal diet, the optimal dietary choline requireme nt for growing P. monodon is about 6200 mg/kg.