Aquaculture Reports最新文献

{"title":"Effects of feeding pattern on growth, immunity and intestinal flora of GIFT tilapia (Oreochromis niloticus) and largemouth bass (Micropterus salmoides)","authors":"Yuning Wang ,&nbsp;Rui Wang ,&nbsp;Ruiyi Yang ,&nbsp;Shaoyu Zhu ,&nbsp;Feng Yao ,&nbsp;Xiaohua Zhang ,&nbsp;Yanou Yang","doi":"10.1016/j.aqrep.2025.102764","DOIUrl":"10.1016/j.aqrep.2025.102764","url":null,"abstract":"<div><div>The omnivorous GIFT tilapia (Genetically Improved Farmed Tilapia (<em>Oreochromis niloticus</em>)) and carnivorous largemouth bass (<em>Micropterus salmoides</em>) were fed in four feeding patterns to compare the compensatory growth for fish species with different feeding habits. These patterns included satiation (control, fed twice a day at satiation), fasting 2 d and re-feeding 8 d and cycling (the daily feeding pattern is the same as that of the control group, the same below), fasting 4 d and re-feeding 16 d and cycling (both cyclical fasting), feeding once every 10 d then 10 d on satiation and cycling (cyclical food restriction), and each pattern is 60 d. The results showed that both fish species failed to obtain compensatory growth during the cyclical fasting. However, both species obtained completely compensatory growth by significantly improving actual feeding rate and feed efficiency ratio during the cyclical food restriction. During the feeding pattern, GIFT tilapia had significantly higher amylase activity, liver and muscle glycogen contents, and significantly lower blood glucose and serum insulin contents. Largemouth bass had significantly higher protease and lipase activities, and lower blood glucose content. Both species had significantly lower relative expression levels of pro-inflammatory factors in livers; GIFT tilapia had significantly lower and largemouth bass had significantly higher anti-inflammatory factors. Furthermore, GIFT tilapia had significantly higher relative abundance of harmful bacteria and lower relative abundance of beneficial bacteria, and intestinal immunity was impaired; largemouth bass changed the opposite, and intestinal immunity was improved. The results suggest that GIFT tilapia improved their carbohydrate utilization efficiency and largemouth bass improved their protein utilization efficiency, in cyclical food restriction, and the two species achieved completely compensatory growth, but GIFT tilapia impaired immunity, and largemouth bass improved immunity.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102764"},"PeriodicalIF":3.2,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LRP6 regulates growth in Litopenaeus vannamei via the Wnt/β-catenin signaling pathway","authors":"Sheng Wang ,&nbsp;Xiaodi Wang ,&nbsp;Hao Yang ,&nbsp;Xuanzheng Di ,&nbsp;Haoyang Li ,&nbsp;Bin Yin ,&nbsp;Ziwei Liu ,&nbsp;Chaozheng Li ,&nbsp;Jianguo He","doi":"10.1016/j.aqrep.2025.102769","DOIUrl":"10.1016/j.aqrep.2025.102769","url":null,"abstract":"<div><div>Low-density lipoprotein receptor-related protein 6 (LRP6) is a crucial coreceptor in the canonical Wnt/β-catenin signaling pathway, that plays a fundamental role in cell growth, development, proliferation, and apoptosis. However, little is known about its effect on growth performance in economic animal including shrimp. In this study, we characterized a homolog of LRP6 in shrimp <em>Litopenaeus vannamei</em>, named LvLRP6, and explored its involvement in growth regulation. Multiple sequence alignments and phylogenetic analyses indicated that LvLRP6 belongs to the invertebrate LRP6 family and has conserved phosphorylation sites with those of LRP6 in other species. Functional investigations via RNAi technology revealed that silencing LvLRP6 via dsRNA injection resulted in a significant reduction in shrimp growth, as indicated by lower weight gain than that in the control group. Mechanistic exploration revealed that LvLRP6 positively modulates the Wnt/β-catenin pathway, leading to increased expression of core components such as glycogen synthase kinase 3 (LvGSK3), β-catenin (Lvβ-catenin), and T-cell factor (LvTcf). Furthermore, LvLRP6 exerted a suppressive effect on LvMSTN (myostatin), a negative regulator of muscle-related genes, while concomitantly increasing myosin levels. Subsequent research revealed that the promoter of LvMSTN contains TCF binding motifs. Dual-luciferase reporter experiments confirmed that the overexpression of LvLRP6 or LvTcf reduced the promoter activity of LvMSTN. Additionally, LvTcf was found to induce the expression of LvLRP6 and a number of Wnt ligands, thus amplifying Wnt/β-catenin pathway activation and reinforcing the growth-promoting feedback loop. The present investigation demonstrated the importance of LRP6 in shrimp growth, which contributes to our knowledge of the molecular processes that underlie crustacean growth and offers a theoretical basis for breeding and genetic enhancement initiatives aimed at enhancing shrimp aquaculture growth performance.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102769"},"PeriodicalIF":3.2,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integration of transcriptome and metabolome reveals tolerance mechanism to high salinity stress in Crassostrea hongkongensis","authors":"Yixin Zhang ,&nbsp;Qiwen Liang ,&nbsp;Feifei Yu ,&nbsp;Jiexiong Zhu ,&nbsp;Jianfang Gui ,&nbsp;Jinji Lin ,&nbsp;Yishan Lu ,&nbsp;Haiyuan Tao","doi":"10.1016/j.aqrep.2025.102759","DOIUrl":"10.1016/j.aqrep.2025.102759","url":null,"abstract":"<div><div><em>Crassostrea hongkongensis</em> (<em>C. hongkongensis</em>) is an important economic species thriving in intertidal and estuarine areas, and suffers frequent salinity fluctuation. In this study, the transcriptomic and metabolomic were conjointly analyzed to reveal the tolerance mechanism of <em>C. hongkongensis</em> in response to high salinity stress. After high salinity stress at sub-lethal concentration (40 ‰) for 48 h, the enzyme activities of SOD, CAT, LZM, GSH-PX and AKP were measured to confirm that <em>C. hongkongensis</em> had activated the physiological stress reoponses. A total of 232 differentially expressed genes (DEGs) and 968 DEGs were identified after salinity stress for 6 h and 48 h, respectively. DEGs enriched pathways mainly included NOD-like receptor signaling pathway, oxytocin signaling pathway, pentose and glucuronate interconversions, NF-kappa B signaling pathway, apoptosis and so on. A total of 33 differential metabolites (DMs) and 61 DMs were identified in 6 h and 48 h salinity-stress groups. KEGG function analysis showed that DMs mainly involved in free amino acids metabolism, pentose and glucuronate interconversions, fatty acids biosynthesis, aminoacyl-tRNA biosynthesis, pantothenate and CoA biosynthesis and so on. Correlation analysis between DEGs and DMs found that the integrated regulatory network was involved in amino acid metabolism, aminoacyl-tRNA biosynthesis, fatty acid degradation, pyrimidine metabolism, etc. The data suggested that high salinity could cause stress response of <em>C. hongkongensis</em> by adjusting osmotic balance, carbohydrates and lipids metabolism and transfer systems. The study provided important information for understanding molecular mechanism of salinity tolerance in oysters.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102759"},"PeriodicalIF":3.2,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143697427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High inclusion of corn gluten meal supplemented with butyric acid; Impacts on growth, immunology, histopathology, and metabolomics of pacific shrimp","authors":"Mpwaga Alatwinusa Yohana ,&nbsp;Gyan Watson Ray ,&nbsp;Kou Shiyu ,&nbsp;Beiping Tan ,&nbsp;Qihui Yang","doi":"10.1016/j.aqrep.2025.102751","DOIUrl":"10.1016/j.aqrep.2025.102751","url":null,"abstract":"<div><div>This research aimed to examine the impacts of adding butyric acid (BA) at elevated levels to corn gluten meal (CGM) in the Pacific shrimp diet. This study analyzed how adding BA to the diet impacts shrimp growth performance, immunology, metabolomics, and histopathological responses. A total of 720 shrimp were divided into six groups, each receiving a different level of BA supplementation: 0 %, 0.5 %, 1 %, 1.5 %, 2 %, and 2.5 %. The experiment spanned 56 days, with three replicates for each group. The initial mean weight of the shrimp was 0.18 ± 0.00 g. The results of the study indicated that final weight (FW), weight gain rate (WGR), and specific growth rate (SGR) all showed significant increases with increased levels of dietary BA (<em>P</em> &lt; 0.05). The survival rate (SR) was 100 % across all treatment groups. Additionally, dietary BA led to a significant decrease in feed conversion ratio (FCR), with the most pronounced effect observed in the 1.5 % BA group (<em>P</em> &lt; 0.05). The addition of BA to the diet resulted in a significant increase in the activities of alkaline phosphatase (AKP) and acid phosphatase (ACP). At the same time, the levels of aspartate and alanine aminotransferase decreased significantly (<em>P</em> &lt; 0.05). Interestingly, malondialdehyde (MDA) levels decreased with higher BA supplementation, but superoxide dismutase (SOD) activity increased in shrimp-fed BA diets. Histological analysis of the hepatopancreas showed that shrimp-fed diets containing 1 % and 1.5 % BA had significantly higher B and R-cell numbers than the control group. Metabolomics analysis revealed that fatty acids such as palmitic acid, docosahexaenoic acid (DHA), stearic acid, and arachidonic acid were up-regulated in BA diets. The slope broken-line regression analysis of WGR against dietary BA levels suggested that the optimal BA requirement for <em>L. vannamei</em> shrimp was estimated to be 1.25 %.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102751"},"PeriodicalIF":3.2,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feeding value of low opportunity cost biomasses (agri-food by-products) for development of circular pond fish feeds: An evaluation with common carp (Cyprinus carpio)","authors":"Felix Kofi Agbeko Kuebutornye ,&nbsp;Anil Axel Tellbüscher,&nbsp;Petr Dvořák,&nbsp;Koushik Roy ,&nbsp;Jan Mraz","doi":"10.1016/j.aqrep.2025.102753","DOIUrl":"10.1016/j.aqrep.2025.102753","url":null,"abstract":"<div><div>In many cases, prior to their inclusion in feed, food system by-products need some sort of refinement. Many options are being explored on how these by-products could aid in direct re-generation of food with the shortest value chain. In this study, we hypothesized that common carp raised semi-intensively in European fishponds could convert waste resources to food directly. The 30 % ingredient replacement method was used to evaluate the digestibility of 12 local waste resources of plant origin as candidates for ‘circular feed ingredients’ for feeding pond fish. It was evident from the results that protein digestion (&gt;70 %) is not an issue, even showing similarities between pre-treated resources (brewery wastes) and non-pre-treated resources (oilseed expellers or legumes) – but lysine or methionine decide from 20 % – 49 % utilization of digested protein from those ingredients. It is therefore, recommended that complementary combination of ingredients be explored to overcome limiting DIAAS in natural food base in ponds. In this case, rapeseed expeller and barley distillers’ grain seem to be closest candidates to fix the lysine and methionine limitation in natural pond food base. Microbial/enzymatic/mechanical pre-processed ingredients such as extract of sugar beet, brewery wastes, bakery or extruded breakfast cereals have low pollution potential (P bioavailability 50–80 %) – contrary to proteinaceous resources (oilseed expellers or broken legumes) which had P bioavailability ≤ 25 % (except pea). Bakery or breakfast cereals discards are novel sources of digestible energy for pond fish (∼400 kcal 100 g−1). Given that NDF:ADF ratio (&gt;2:1) allow for easy fermentation in gut, besides possibly laced with microbial enzymes or some pre-hydrolysis, the undigested fibers in sugar beet, legumes, or oilseed expeller (AD carbohydrate 1–20 %) could boost pond food web through microbial upcycling. This study highlights the possibility of developing circular, less-refined semi-intensive pond fish feeds “commercially”. Such feed could enhance resource use efficiency at food-system level.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102753"},"PeriodicalIF":3.2,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regulatory patterns of testis and ovary maturation in largemouth bass (Micropterus salmoides) revealed by transcriptome profiling","authors":"Qingchun Wang ,&nbsp;Siqi Lu ,&nbsp;Jixiang Hua ,&nbsp;Yifan Tao ,&nbsp;Yan Zhuge ,&nbsp;Wenhua Chen ,&nbsp;Xuejun Duan ,&nbsp;Jun Qiang","doi":"10.1016/j.aqrep.2025.102761","DOIUrl":"10.1016/j.aqrep.2025.102761","url":null,"abstract":"<div><div>Largemouth bass (<em>Micropterus salmoides</em>) is an economically significant farmed fish. It would be useful to understand its gametic maturation to establish effective breeding populations. We conducted histological analyses, transcriptome sequencing, and fluorescent <em>in situ</em> hybridization (FISH) analyses to detect differences in gene expression between ovaries and testes of sexually mature largemouth bass (6.5 months old). Analyses of differentially expressed genes and a gene set enrichment analysis identified 32 genes associated with gametic maturation (17 in ovaries; 15 in testes). Those in the ovaries included <em>elovl1a</em>, <em>hsd17b12a</em>, <em>cidec</em>, and <em>acls5</em>, encoding enzymes involved in lipid biosynthesis in stage III and IV oocytes; <em>lrp13</em> and <em>iars2</em>, encoding proteins involved in yolk particle synthesis; and <em>cpeb1b</em>, <em>cth1</em>, and <em>ccnb1</em>, encoding proteins involved in the initiation and termination of meiosis to ensure oocyte maturation. The important genes in the testes were associated with the formation and assembly of microtubule structures. They included <em>cfap161</em>, <em>spag6</em>, <em>iqub</em>, <em>enkur</em>, <em>tekt1</em>, <em>mns1</em>, <em>gas8</em>, and <em>ccdc40</em>, encoding proteins involved in the regulation of the structural formation of sperm flagella; and <em>lrguk</em>, <em>spef2</em>, and <em>tdrd5</em>, encoding proteins involved in the initiation of spermatid assembly and maturation to form sperm — a critical stage in spermatogenesis. The transcriptome data and FISH results revealed high expression of <em>dmrt1</em> in the extracellular matrix of spermatogonia cells, and of <em>btg4</em> in the cytoplasm of stage IV oocytes. These two genes may serve as crucial regulatory factors in the maturation of testes and ovaries, respectively. Our findings offer insights into the mechanisms underlying gonad maturation in largemouth bass.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102761"},"PeriodicalIF":3.2,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"More than just a pinch of salt? The impact of increasing salinity on maraena whitefish in different husbandry systems","authors":"Alexander Rebl ,&nbsp;Frederike Schmachtl ,&nbsp;Ronald M. Brunner ,&nbsp;Carsten Kühn ,&nbsp;Fabian Swirplies ,&nbsp;Tom Goldammer","doi":"10.1016/j.aqrep.2025.102758","DOIUrl":"10.1016/j.aqrep.2025.102758","url":null,"abstract":"<div><div>The present study investigated the influence of different salinity concentrations on gene expression patterns in maraena whitefish (<em>Coregonus maraena</em>) from three aquaculture facilities. Over a period of 10 weeks, we compared maraena whitefish from the same batch of fertilised eggs that were kept in a freshwater-pond system and a net-cage facility in the southwestern Baltic Sea, where periodic saline intrusions from the North Sea occur. Having demonstrated differential expression of the two variants of the well-established <em>atp1a1</em> biomarker gene in gills of maraena whitefish from both habitats, we profiled the expression levels of a further 22 seawater-tolerance biomarkers in the gills, skin, head kidney and liver. The expression profiles were largely consistent across whitefish from both habitats, with only sporadic modulations. A principal component analysis revealed that these differential expression patterns were dominated by <em>eef2</em>, <em>ghr</em> and <em>wasf1.</em> A subsequent salinity experiment, carried out in a recirculating aquaculture system under constant environmental conditions, revealed that increases in salinity from 0 to 8 Practical Salinity Units (PSU) resulted in significantly elevated transcript levels of <em>fkbp5</em> and <em>atp1a1a</em> in the gills. The reduced levels of <em>eef2</em>, <em>ghr, wasf1, nampt</em> and <em>uba1</em> in the head kidney, skin or both tissues indicated a response mechanism to higher salinity (20 PSU). Altogether, only the quantification of the <em>atp1a1a</em> gene in the gill tissue provided reliable evidence of successful acclimation from low- to high-salinity water in all three facilities investigated. Based on the overall transcriptional data and the generally good fish physical constitution, we assume that maraena whitefish were not negatively affected by salinities up to 20 PSU suggesting their ability to tolerate dynamic brackish-water environments.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102758"},"PeriodicalIF":3.2,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparing the effect of different carbon sources on growth, blood parameters, immunity, and water quality in Nile Tilapia (Oreochromis niloticus) cultured in a biofloc system","authors":"Mai H. Hussien ,&nbsp;Mohamed M. Zayd ,&nbsp;Ahmed E. Elshafey ,&nbsp;Malik M. Khalafalla ,&nbsp;Mustafa Shukry ,&nbsp;Mohamed Abdelmegeid ,&nbsp;Lamiaa A. Okasha ,&nbsp;Rabiha Seboussi ,&nbsp;Mohamed H. Aboraya ,&nbsp;Ahmed A. Elolimy","doi":"10.1016/j.aqrep.2025.102755","DOIUrl":"10.1016/j.aqrep.2025.102755","url":null,"abstract":"<div><div>Aquaculture faces significant challenges in maintaining water quality and fish health. This study evaluated the effects of different carbon sources on growth, immunity, and water quality in Nile tilapia (initial weight: 2.8 ± 0.002 g) cultured in a biofloc system over 90 days. Five treatment groups were tested, including a control group without carbon supplementation (T1) and groups supplemented with molasses (T2), vinasse (T3), starch (T4), or rice bran (T5). Results showed that molasses significantly improved (p &lt; 0.05) growth performance, feed efficiency, and hematological parameters, suggesting enhanced oxygen-carrying capacity and immune function. Additionally, molasses increased glucose, triglycerides, and albumin levels, improving liver function and energy metabolism. Immune responses, including lysozyme activity, IgM levels, and phagocytic activity, were significantly enhanced in the molasses group. Antioxidant enzyme activity was higher, and oxidative stress indicators were lower in this group. Histological analysis revealed improved intestinal and gill morphology in fish reared on molasses. Water quality parameters, such as pH, dissolved oxygen, and total ammonia nitrogen, were positively affected by vinasse and starch. Gene expression analysis indicated molasses-influenced genes associated with stress response, antioxidant activity, inflammation, and growth. These findings suggest that molasses is a promising carbon source for biofloc systems, improving growth, health, and water quality in Nile tilapia aquaculture.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102755"},"PeriodicalIF":3.2,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of pharmacological inhibition of signal transduction pathways in steroid-induced oocyte maturation in rainbow trout","authors":"Gregory M. Weber,&nbsp;Lisa M. Radler,&nbsp;Jill E. Birkett","doi":"10.1016/j.aqrep.2025.102760","DOIUrl":"10.1016/j.aqrep.2025.102760","url":null,"abstract":"<div><div>Gonadotropins, steroids and insulin family growth factors act throughout the follicle-oocyte complex to regulate ovarian follicle maturation. Induction of oocyte maturation by the maturation inducing hormone (MIH) and insulin/insulin-like growth factor (IGF) peptides have received the most attention in lower vertebrates. The actions and receptor signaling pathways of these hormones often overlap and vary among species. The phosphatidylinositol-3 kinase (Pi3K) pathway, a primary signaling pathway for growth factors, is required not only for growth factor actions, but also for optimal gonadotropin and MIH induction of oocyte maturation in many fish species. The species-specific involvement of the Pi3K pathway in the integration of growth factor and MIH induction of ovarian follicle maturation and oocyte maturation is not well understood. Discovering the physiological basis for this variation will contribute to understanding the evolution of diverse reproductive strategies among fishes. Rainbow trout, (<em>Oncorhynchus mykiss</em>), appear unusual in that insulin and IGFs cannot induce resumption of meiosis or competence of the oocyte to respond to the MIH, 17,20βP, making it an interesting species to investigate Pi3K pathway signaling by MIH. In the present study, 17,20βP induction of meiosis resumption and Mapk activation were blocked or attenuated by pharmacological inhibition of Pi3K (wortmannin, LY294002) or Mek (PD98059, U0126), but were not affected by inhibitors of Akt (ML-9) or mTOR (rapamycin). The results indicate Pi3K and Mapk activation are required for optimal MIH-induction of meiosis resumption in rainbow trout follicles and may be required in other fishes in which insulin or IGFs do not directly induce competence or oocyte maturation.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102760"},"PeriodicalIF":3.2,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of dietary protein levels on growth, immune response, digestibility, intestinal microbiota, and transcriptome in Litopenaeus vannamei fed cottonseed protein concentrate","authors":"Hongming Wang ,&nbsp;Xin Hu ,&nbsp;Jian Chen ,&nbsp;Yudong Zheng ,&nbsp;Beiping Tan ,&nbsp;Lili Shi ,&nbsp;Shuang Zhang","doi":"10.1016/j.aqrep.2025.102762","DOIUrl":"10.1016/j.aqrep.2025.102762","url":null,"abstract":"<div><div>This study investigated the effects of dietary protein levels on <em>Litopenaeus vannamei</em> using cottonseed protein concentrate (CPC) as the primary protein source. <em>L. vannamei</em> (initial body weight = 0.42 ± 0.01 g) were fed diets containing 32 % (CPC32), 36 % (CPC36), 40 % (CPC40), 44 % (CPC44), and 48 % (CPC48) protein for 8 weeks. The CPC40 group exhibited the highest final body weight (FBW), weight gain rate (WGR), specific growth rate (SGR), and the lowest feed conversion ratio (FCR). Analysis of hepatopancreatic tissues revealed that activities of superoxide dismutase (SOD), peroxidase (PO), lysozyme (LZM), and catalase (CAT) were significantly reduced, while malondialdehyde (MDA) levels increased in the CPC48 group compared to the CPC40 group. The activities of trypsin and amylase were significantly decreased in the CPC32 and CPC48 groups compared to CPC40, with a notable decrease in trypsin activity also observed in the CPC36 group. Intestinal microbiota analysis showed significant shifts in the CPC40 group, including an increased Bacteroidetes to Proteobacteria ratio and higher relative abundances of Verrucomicrobia, Flavobacteriaceae, Demequinaceae, and <em>Photobacterium</em>. Transcriptomic analysis identified significant signaling pathways affected by dietary treatments, notably the IL-17 signaling pathway, endoplasmic reticulum protein processing, and cholesterol metabolism. Key genes such as <em>HSP90B1</em> and <em>HSP90AA1</em> were prominently involved in various pathways, including IL-17 signaling, thyroid hormone synthesis, fluid shear stress, prion disease, and atherosclerosis. Correlation analysis indicated a significant positive relationship between <em>HSP90B1</em> gene expression and <em>Photobacterium</em> abundance. Furthermore, gene expression levels of <em>HSP90B1</em> and <em>HSP90AA1</em> in hemocytes were significantly elevated in the CPC32 and CPC48 groups compared to CPC40. In conclusion, the CPC40 diet may enhance immune pathways in <em>L. vannamei</em> through the synergistic modulation of the <em>HSP90B1</em> gene and <em>Photobacterium</em>, leading to reduced intestinal pathogenic bacteria, improved immunity and digestive efficiency, ultimately promoting growth performance.</div></div>","PeriodicalId":8103,"journal":{"name":"Aquaculture Reports","volume":"42 ","pages":"Article 102762"},"PeriodicalIF":3.2,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}