EFFECTS OF FEEDING FREQUENCY ON GROWTH,BODY COMPOSITION,DIGESTIVE SYSTEM ENZYME ACTIVITY,AND TISSUE STRUCTURE OF JUVENILE HAPALOGENYS MUCRONATUS
To explore the optimal effects of feeding frequency on growth performance,nutrient composition,digestive enzyme activity,and digestive system morphology of juvenile Hapalogenys mucronatus,juveniles of initial body weight of(7.13±0.93)g were randomly selected and divided into four triplicated groups(20 fish per each replicate)for study.The feeding frequency of the four experimental groups was 1 time/d(F1),2 times/d(F2),3 times/d(F3),and 4 times/d(F4).The experiment lasted for 8 weeks.Results show that the final body weight,weight gain rate,specific growth rate,and feeding rate increased with the increase of feeding frequency,but there was no significant difference between F3 and F4 groups.Compared with F1 group,the final body weight of F4 group increased by 8.29 g,the weight gain rate increased by 63％,the feeding rate increased by 20％,and the specific growth rate increased by 32％.The condition factor and crude protein content of F3 group were the highest,and the crude fat and ash content were the lowest.The activity of pepsin in the stomach gradually decreased due to the feeding frequency.Lipase was the lowest in F4 and amylase was the highest in Fl.The activity of pepsin in hindgut was generally＞foregut＞midgut,and the activities of lipase and amylase were generally higher than those in foregut and midgut.The activity of liver pepsin was the highest in F4,and the activity of lipase and amylase was the highest in F2.The intestinal morphological structure of H.mucronatus with different feeding frequencies was different,and the intestinal wall thickness of F4 group was thinner.Therefore,from the perspective of promoting the growth,muscle nutrients,and intestinal health of juvenile H.mucronatus,the appropriate feeding frequency of the juveniles is 3 times/d.
万方数据
维普
