The Effects Of Inositol And Zinc In Low-fishmeal Dietary On Nutritional Physiological Functions For Jouvenile L.Vannamei And (Epinephelus Lanceolatu?×Epinephelus Fuscoguttatus?),Respectively

This study was to investigate the effects of myo-inositol and Zn on growth performance,enzyme activities and intestinal flora of juvenile Litopenaeus vannamei,juvenile Epinephelus lanceolatu ? × Epinephelus fuscoguttatus ?.The results of four experimental studies in this paper are as follows:1.An 8-week feeding trial was carried out to investigate the effects of myo-inositol on growth performance,nonspecific immune enzyme activities and intestinal flora in juvenile Litopenaeus vannamei under low fish meal conditions.In this experiment,there were 8groups,4 barrels in each group,40 shrimps per barrel,and a total of 1280 tail weight(0.65±0.01)g of healthy and even prawn shrimps were selected as experimental materials.Add different amounts of 0 mg/kg(high fishmeal control group),0 mg/kg(low fishmeal control group),150 mg/kg,300 mg/kg,600 mg/kg,900 mg/kg,1200 mg/kg,2000 mg / kg inositol was made into 8 kinds of feed and fed.The results showed that the addition of inositol to feed had no significant effect on the survival rate of juveniles of P.vannamei(P>0.05).The weight gain rate,specific growth rate and protein efficiency of the high fish meal control group were significantly higher than those of the low fish meal group(P<0.05).The feed coefficient was significantly lower(P<0.05);the specific growth rate and weight gain rate under low fishmeal conditions reached a maximum when the amount of inositol was 1200 mg/kg;when the amount was 150 mg/kg,the feed coefficient The lowest was 1.46,and the other added groups were significantly lower than the control group(P<0.05).Serum TP,TG,TC increased first and then decreased.The contents of SOD,PO,T-AOC and C3 were significantly higher in the added group than in the control group(P<0.05).There was no significant difference in the number of OTUs in the whole intestine of Penaeus vannamei,and there was no significant difference between the control group and the added group under low fishmeal conditions(P>0.05).Based on thepolynomial model,the addition of 1761.5 mg/kg inositol to the feed significantly promoted the growth performance of shrimp and increased non-specific immunoenzyme activity.2.An 8-week feeding trial was carried out to investigate the effects of myo-inositol on growth performance,antioxidase activity and intestinal flora in juvenile Epinephelus lanceolatu ? × Epinephelus fuscoguttatus ? under low fish meal conditions.In this experiment,8 groups,4 replicates,each repeating 30 fish,a total of 960 weights(7.40±0.01)g of healthy and uniform pearl gentian grouper juveniles were selected as experimental materials.Add different amounts of 0mg/kg(high fishmeal control group),0mg/kg(low fishmeal control group),150mg/kg,300mg/kg,600mg/kg,900mg/kg,1200mg/kg,2000mg/kg inositol respectively Made into 8 kinds of feed and fed,the breeding cycle is 8 W.Experimental results: The level of inositol addition had no significant effect on the WGR,SGR,FCR and PER of grouper(P>0.05).TG,TC,and HDL-C were all significantly improved,and LDL-C was significantly reduced.The results of intestinal flora showed that the number of OTUs in the foregut under low fishmeal conditions was significantly higher in the 1200 mg/kg and 2000 mg/kg groups than in the control group(P<0.05);the number of OTUs in the midgut and hindgut was added.There was no significant effect between the group and the control group(P>0.05).The weight gain rate was used as the basis for judging.The addition of 200.89 mg/kg inositol in the feed significantly increased the growth performance of the gentian grouper and improved the serum and liver enzyme activities.3.An 8-week feeding trial was carried out to investigate the effects of Zn on growth performance,nonspecific immune enzyme activities,resistance to disease and intestinal flora in juvenile Litopenaeus vannamei under low fish meal conditions.In this experiment,8 groups were designed,4 barrels in each group,40 shrimps per barrel.A total of 1280 tail weights(0.45±0.01)g of healthy and uniform penaeid shrimp were used as experimental materials.Feeding different amounts of 0mg/kg(high fishmeal control group),0mg/kg(low fishmeal control group),20mg/kg,40mg/kg,60mg/kg,80mg/kg,100mg/kg,150mg/kg zinc respectively Made into 8 different feeds and fed,the breeding cycle is 8 W.Experimental results: Under low fishmeal conditions,the weight gain rate and specific growth rate of the 60 mg/kg addition group were significantly higher than the low fish meal control group(P<0.05),lower than the high fish meal group(P<0.05);when 80 mg was added At /kg,the feed coefficient was the lowest,the other groups were significantly lower than the low fish meal control group(P<0.05);when the addition amount was 80mg/kg,the protein efficiency was the highest.The serum biochemical parameters TP,TG,T-CHO,HDL-C and LDL-C were significantly higher than those in the control group under low fishmeal conditions(P<0.05),and decreased with the increase of zinc.The activities of T-AOC and SOD were significantly higher in the added group than in the low fish meal control group(P<0.05).The number of OTUs in the whole intestine of Penaeus vannamei was significantly higher in the low fishmeal conditions than in the control group(P<0.05).After 96 h of challenge with Vibrio harveyi,the survival rate of L.vannamei was significantly higher than that of the control group under low fishmeal conditions(P<0.05).Based on the weight gain rate,the addition of 94.46 mg/kg zinc in the feed significantly promoted the growth of P.vannamei and improved disease resistance.4.An 8-week feeding trial was carried out to investigate the effects of Zn on growth performance,immune enzyme activities,resistance to disease and intestinal flora in juvenile Litopenaeus vannamei under low fish meal conditions.In this experiment,8groups were set up,4 replicates in each group,and 30 fishes were repeated for each.A total of 960 heavier weights(12.00±0.01)g of healthy and uniform pearl gentian grouper juveniles were selected as experimental materials.Different doses of 0 mg/kg(high fishmeal control group),0 mg/kg(low fishmeal control group),20 mg/kg,40 mg/kg,60mg/kg,80 mg/kg,100 mg/ Kg,150mg/kg zinc were made into 8 different feeds and fed,and the breeding cycle was 8 W.The results showed that the WGR and SGR addition groups were significantly higher than the control group under low fishmeal conditions(P<0.05).When the addition amount was 40mg/kg,the FCR was the lowest,and the other groups were significantly lower than the low fishmeal control group(P<0.05).);and the change rule of PER is opposite to FCR.The serum T-AOC and SOD activities reached a maximum at the addition of 20 mg/kg.Through intestinal flora analysis,zinc had no significant effect on the effective OTUs in the foregut of juvenile gentian grouper(P>0.05);the number of midgut OTUs was significantly higher in the fishmeal control group than in the low-fishmeal control group(P<0.05).Under the condition of low fishmeal,the20mg/kg addition group was significantly higher than the control group(P<0.05),and the100mg/kg addition group was significantly lower than the control group(P<0.05).There was no significant difference between the other added groups and the control group(P>0.05);the number of late intestine OTUs was not significantly different between the fishmeal control group and the low fishmeal control group(P>0.05).Under the low fishmeal condition,the control group was significantly lower than the 80mg/kg zinc addition group(P<0.05).There was no significant difference between the groups(P>0.05).After 7 days of Vibrio harvey challenge experiment,the survival rate of pearl gentiangrouper in the low fish meal condition was significantly higher than that in the control group(P<0.05).Based on the weight gain rate WGR,the addition of 22.9mg/kg zinc to the feed under low fishmeal conditions can significantly promote the growth of the pearl gentian grouper and improve disease resistance.