Cloning And Tissue Expression Of ACC,CPT-Ⅰ And Effects Of Different Diets On Growth,Digestive Capacity Of Juvenile Red Swamp Crayfish(Procambarus Clarkii)

In this study,the partial sequences of the acetyl-Co A carboxylase(ACC)gene and full length CDS of carnitine acyltransferase-Ⅰ(CPT-Ⅰ)gene from Procambarus clarkii were cloned.And the tissue expression distribution of ACC and CPT-Ⅰ were analyzed.At the same time,the effects of compound diet and fermented diet on growth and digestive capacity of juvenile red swamp crayfish were investigated.These results lay a foundation for studying fat metabolism and provide relevant theoretical support for the healthy culturing of red swamp crayfish using artificial feed.Study 1: Cloning and tissue expression analysis of acetyl-Co A carboxylase and carnitine palmitoyl transferase-Ⅰ gene from Procambarus clarkiiTo clone the partial sequences of ACC gene and full length CDS of CPT-Ⅰ gene fom Procambarus clarkii,the ACC gene from Macrobrachium nipponense and CPT-Ⅰ gene conservative sequences from Macrobrachium nipponense,Eriocheir sinensis and Penaeus vannamei were used as template,and the relative expression levels of ACC and CPT-Ⅰ of heart,hepatopancreas,muscle,and intestine tissue of Procambarus clarkii were detected.The results showed that:(1)The partial sequences of ACC gene and full length CDS of CPT-Ⅰ gene fom Procambarus clarkii were successfully cloned.The ACC gene partial sequences with 1286 bp is the highest homology with the ACC gene from Portunus trituberculatus,reaching 76.25%.The full-length CDS of CPT-Ⅰ gene has 2328 bp and encodes 775 amino acids.The CPT-Ⅰprotein sequence has the highest homology with the CPT-Ⅰ protein from Penaeus vannamei,reaching 82.71%.(2)The relative expression of ACC gene of hepatopancreas was significantly higher than that of heart,muscle and intestine;the relative expression of CPT-Ⅰ gene of muscle was significantly higher than that of hepatopancreas,muscle and intestine(P<0.05).Study 2: Effects of different diets on growth and digestive capacity of juvenile Procambarus clarkiiTo investigate the effects of different diets on growth and digestive capacity of Procambarus clarkii.A total of 900 healthy juvenile crayfish(initial weight 0.28±0.01g)were randomly assigned to control group(with no feed,A),compound diet group(fed with compound diet,B),and fermented diet group(fed with fermented diet,C),3 replicates each group,and 100 crayfish each replicate.The experiment lasted for 32 days and results showed that:(1)The FBW,PWG and SGR of juvenile crayfish fed with compound diet were significantly higher than those fed with compound diet and with no feed(P<0.05);but no significant difference in SR was detected(P>0.05).(2)The IFH,IFW,IFSA,amylase,lipase activities of stomach and hepatopancreas,and trypsin activities of intestine of juvenile crayfish fed with compound diet and fermented diet were significantly higher than those crayfish with no feed(P<0.05).The IFH,IFSA,trypsin,amylase activities of stomach and hepatopancreas,and trypsin activities of intestine of juvenile crayfish fed with fermented diet were significantly higher than those crayfish fed with compound diet(P<0.05).(3)The activities of ASA,AHR,T-SOD,CAT of juvenile crayfish fed with compound diet and fermented diet were significantly higher than those crayfish with no feed(P<0.05),and the contents of MDA and PC in hepatopancreas of juvenile crayfish fed with compound diet and fermented diet were significantly lower than those crayfish with no feed(P<0.05).The contents of T-GSH and the activities of T-SOD,CAT,GST of juvenile crayfish fed with fermented diet were significantly higher than those crayfish fed with compound diet,and the MDA and PC contents in hepatopancreas of juvenile crayfish fed with fermented diet were significantly lower than those crayfish fed with compound diet(P<0.05).The activities of FAS,LPL and HSL in hepatopancreas of juvenile crayfish fed with compound diet and fermented diet were significantly lower than those crayfish with no feed(P<0.05).The activities of FAS and SCD in hepatopancreas of juvenile crayfish fed with fermented diet were significantly lower than those crayfish fed with compound diet,and the activities of LPL and HSL in hepatopancreas of juvenile crayfish fed with fermented diet were significantly higher than those crayfish fed with compound diet(P<0.05).In conclusion,these results suggest that:(1)The ACC gene fom Procambarus clarkii has the highest homology with the ACC gene from Portunus trituberculatus,and it is mainly expressed in hepatopancreas tissue.The encoded protein sequence of CPT-Ⅰ gene from Procambarus clarkii has the highest homology with the CPT-Ⅰ protein from Penaeus vannamei,and the CPT-Ⅰ gene from Procambarus clarkii is mainly expressed in muscle tissue.(2)The compound diet and fermented diet can reduce the oxidative damage of the hepatopancreas of juvenile crayfish,improve the secretion of digestive enzymes,promote the development of intestine,then improve the digestibility and promote the growth and development of juvenile crayfish,and the effects of fermented diet is better than compound diet.