Effect of different levels of choline chloride on intestinal bacterial flora in rainbow trout (Oncorhynchus mykiss) fry

The present study was designed and conducted to investigate the effects of varying levels of choline chloride on the microbial flora of the rainbow trout, Oncorhynchus mykiss fry. A total of 750 fish were fed with diets containing 0 (control), 250 (Cho250), 500 (Cho500), 1000 (Cho1000), and 2000 (Cho2000) mg of choline chloride per kg of feed for 90 days. The required feed was obtained from the 21 Bayza Company. The amount of microbial flora and final weight was significantly higher in the Cho1000 and Cho2000 than in the control group. The addition of choline to the diet effectively improved the microbial flora. The most suitable amount of choline chloride was between 1000 and 2000 mg/kg in the diet of rainbow trout.