The Effect Of Concentrated Dephenolic Cottonseed Protein In Place Of Fish Meal On The Growth And Stress Resistance Of Penaeus Monodon And Its Transcriptome Research

Penaeus monodon is not only one of the most important farmed economic shrimps in the world,but also an important marine aquaculture object in southern China.In the past ten years,the overall production of Penaeus monodon culture has shown an upward trend,which also highlights the economic development value of Penaeus monodon.The development of aquaculture industry has continuously increased the demand for feed materials.At present,the shortage of fishmeal has become a key factor restricting the development of aquaculture industry.In order to solve the pressure of insufficient supply of fishmeal raw materials caused by the rapid development of aquaculture,we need to find more diversified plant protein sources to replace fishmeal,which is of great significance to the sustainable development of aquaculture.This study used concentrated dephenolic cottonseed protein to replace 66.67%of fish meal in the artificial diet of Penaeus monodon to study the growth and survival of Penaeus monodon,the ability to resist stress,and the expression of genes related to growth and immunity at this replacement level.To provide some theoretical references for future research on substitutes of fish meal in Penaeus monodon.The results of the three experiments are as follows:1.The effect of concentrated dephenolic cottonseed protein instead of fish meal on the growth performance of 15 families of Penaeus monodonPenaeus monodon was used as the research object,and two different kinds of fish meal content were made to feed it.The control group DietA contained 30%fish meal;the experimental group DietB contained 10%fish meal.Three experiments were designed.Experiment 1:Select 15 families of Penaeus monodon with similar spawning period to conduct pure marine culture experiments with a salinity of 30.The average weight of the experimental families is between 1.96-2.06g.After each family was fluorescently labeled,150 shrimps were randomly selected,and 50 shrimps were randomly allocated to each feed parallel group.After the 56-day breeding experiment,the body length,weight and number of surviving shrimps of each family were counted.The survival rate of the DietA family of Penaeus monodon in the control group was 72.51%-86.52%,and the survival rate of the DietB family of the experimental group of Penaeus monodon was 72.96%-84.62%.The average survival rates of the DietA and DietB groups were 81.15%and 76.87%,respectively.The average survival rate of DietB group was lower than that of DietA group,and the coefficient of variation of DietB group was higher than that of DietA group.In the two Dietgroups,the coefficient of variation of body length was greater than the coefficient of variation of body weight.Among them,the coefficient of variation of body length in the control group was 32.45%,and the coefficient of variation of body length in the experimental group was 37.36%;the coefficient of variation of body length in the control group and the experimental group was 22.71%,22.84%respectively.The absolute weight gain rate(AGR)of DietA group and DietB group were 0.14-0.28 and 0.13-0.27,respectively.The AGRs of the families with the fastest weight gain in the DietA group and DietB group were 100.00%and 107.69%higher than those of the families with the slowest weight gain,respectively.At the same level of significance,the top 10%of families were selected as fast-growing families,and families No.10 and No.6 performed well in the two different feed groups.Families adapted to low fish meal protein level feed have certain advantages in terms of growth and survival rates during the breeding process.Families No.10 and No.6 show good production performance and have the potential for further genetic improvement.2.The effect of concentrated dephenolic cottonseed protein instead of fish meal on non-specific immune indexes and stress resistance of Penaeus monodonPut the penaeus monodon after the statistics of experiment 1 into a black breeding bucket for three days,and then set up two treatment groups with salinity of 10 and 20,and select the average weight from DietA group and DietB group respectively14.71g/tail Penaeus monodon and the acute salinity stress test of the control group DietA and the experimental group DietB respectively,and take them at the time points of 0h,8h,16h,24h,32h,40h,and 48h.The hepatopancreas are preserved.After that,four non-specific immune indexes of alkaline phosphatase(ALP),cortisol,Na~+-K~+-ATPase and heat shock protein 70 were measured.After 56 days of culture experiment,the ALP activity of P.monodon in the DietB group was higher than that of the DietA group,and there was a significant difference(P<0.05);the cortisol,heat shock protein-70,Na~+-K~+-ATPase of the DietB group of P.monodon was higher than that of DietA group,and was extremely significant(P<0.01).This indicates that concentrated dephenolic cottonseed protein improves the non-specific immunity of P.monodon.The effect of acute stress with a salinity of 10 on the non-specific immune indexes of Penaeus monodon was found that compared with the experimental group DietB,after 8 hours of stress,the ALP activity of the DietA group reached the highest,which was very significantly significantly higher than that of the DietB group(P<0.01),followed by a decrease at 16h.The HSP70 of DietA group reached the highest at 8h,which was significantly higher than that of DietB group(P<0.01),DietB group rose to the highest at 24h,DietB group reached the highest level of cortisol expression at 0h,and then showed a trend of decreasing and then increasing;Na~+-K~+-ATPase activity all showed a trend of first increasing and then decreasing,while the DietA group reached the highest level at 16h Na~+-K~+-ATPase,and the DietB group reached the highest level at 32h.The results showed that the acute stress with a salinity of 20 affects the non-specific immune indexes of Penaeus monodon.The hepatopancreas ALP of the DietA group and the DietB group showed a turning point from increasing to decreasing after 16 hours of acute stress.The expression of HSP70 in the DietA group and the DietB group both showed an inflection point from rising to decreasing at 16h,and the expression of cortisol in the hepatopancreas of the DietA and DietB groups increased at 8h,and an inflection point from rising to decreasing at 16h;The expression of Na~+-K~+-ATPase in DietA group and DietB group showed an increasing trend from 0 h to 16 h,and their expression level at 48 h was at an increased level compared with 0 h.3.Analysis of the sequencing data of the hepatopancreatic transcriptome of Penaeus monodontwo groups of Penaeus monodon with two feeds of the control group DietA and the experimental group DietB,each with 200 tails of Penaeus monodon,with an average weight of 5.45-6.37g/tail.After 56 days of culture,the hepatopancreas of the two groups were stored at-80°C and sent to the company for transcriptome sequencing.The original sequencing data was assembled to obtain a total of 73554 transcripts and 66670 unigenes.According to the transcriptome data,there are a total of 13236Unigenes annotated by the GO database.The GO database mainly divides unigenes into three categories.Among the cell components,the cell contains unigenes the largest proportion(34.76%),followed by the cell portion(34.56%);in the molecular function,the catalytic activity contains the largest proportion of unigenes(56.47%),followed by binding(45.26%);in biological processes,the metabolic process contains the most unigenes(52.24%),followed by cellular processes(45.27%).Species annotation data showed that the proportion of homologous sequences annotated to Penaeus vannamei accounted for 49.54%,ranking first.Followed by Ralstonia,accounting for 5.59%.The10937 unigenes annotated by KEGG are distributed in 356 pathways.The first five metabolic pathways are 328 ribosomes(ko03010),274 purine metabolism(ko00230),213 PI3K-Akt signaling pathways(ko04151),and oxidative phosphorylation.(Ko00190) 212 pieces,adhesion spots(ko04510)211 pieces.A total of 118 differentially expressed genes were obtained,with 74 up-regulated genes and 44 down-regulated genes.