Fishes最新文献

{"title":"Effect of a Guar Meal Protein Concentrate in Replacement of Conventional Feedstuffs on Productive Performances and Gut Health of Rainbow Trout (Oncorhynchus mykiss)","authors":"Alessandra Roncarati, L. Galosi, Alessandro Di Cerbo, Martina Quagliardi, Francesco Marchetti, Elisa Fiordelmondo, Francesca Mariotti, G. Magi","doi":"10.3390/fishes9080295","DOIUrl":"https://doi.org/10.3390/fishes9080295","url":null,"abstract":"A trial was performed to investigate the effect of a proprietary guar protein concentrate, as a partial replacement of conventional protein sources, on the productive performances of rainbow trout through the growing phase. A total of 2700 rainbow trout were reared in 3 m3, 12 concrete tanks for 90 days. Three diets were formulated to contain a protein level of 43% and a lipid content of 25.3% by replacing 0% (CD), 5% (D5), and 15% (D15) of conventional protein sources with guar protein concentrate. The final mean weight was similar between D5 and CD, significantly higher than D15. The same trend was observed in weight gain and specific growth rate. The feed conversion rate had the most favourable performances in D5 and CD. Feed palatability was higher in CD and D5 than in D15. Histological intestinal score showed significant differences (p < 0.05) between the groups with the highest values in CD and the lowest in D15. Significant differences were observed for goblet cell hyperplasia with higher values in the CD group. Based on this trial, the 5% guar protein concentrate inclusion gave the best zootechnical results.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141805137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"RTL-YOLOv8n: A Lightweight Model for Efficient and Accurate Underwater Target Detection","authors":"Guanbo Feng, Zhixin Xiong, Hongshuai Pang, Yunlei Gao, Zhiqiang Zhang, Jiapeng Yang, Zhihong Ma","doi":"10.3390/fishes9080294","DOIUrl":"https://doi.org/10.3390/fishes9080294","url":null,"abstract":"Underwater object detection is essential for the advancement of automated aquaculture operations. Addressing the challenges of low detection accuracy and insufficient generalization capabilities for underwater targets, this paper focuses on the development of a novel detection method tailored to such environments. We introduce the RTL-YOLOv8n model, specifically designed to enhance the precision and efficiency of detecting objects underwater. This model incorporates advanced feature-extraction mechanisms—RetBlock and triplet attention—that significantly improve its ability to discern fine details amidst complex underwater scenes. Additionally, the model employs a lightweight coupled detection head (LCD-Head), which reduces its computational requirements by 31.6% compared to the conventional YOLOv8n, without sacrificing performance. Enhanced by the Focaler–MPDIoU loss function, RTL-YOLOv8n demonstrates superior capability in detecting challenging targets, showing a 1.5% increase in mAP@0.5 and a 5.2% improvement in precision over previous models. These results not only confirm the effectiveness of RTL-YOLOv8n in complex underwater environments but also highlight its potential applicability in other settings requiring efficient and precise object detection. This research provides valuable insights into the development of aquatic life detection and contributes to the field of smart aquatic monitoring systems.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141808864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wetted Ramps Selectively Block Upstream Passage of Adult Sea Lampreys","authors":"Uli Reinhardt, Nicholas Corniuk","doi":"10.3390/fishes9080293","DOIUrl":"https://doi.org/10.3390/fishes9080293","url":null,"abstract":"Dams fragment stream habitats and fishways around dams typically serve few species that are strong swimmers or jumpers. We tested a prototype wetted ramp designed to allow upstream passage of small-bodied fishes while blocking upstream movement of invasive sea lampreys in the Laurentian Great Lakes. We tested short, smooth ramps with 5–10 mm water depth in various combinations of ramp angle, water flow, and swim channel width with the aim to selectively block adult migrating sea lampreys (Petromyzon marinus) while passing sub-adult white suckers (Catostomus commersonii) and creek chubs (Semotilus atromaculatus). Sea lampreys easily passed a 0.75 ramp at a 5° angle, but very few individuals passed a similar ramp at a 10° angle, and none passed a longer ramp at a 5° angle. Limiting the amplitude of tailbeats in a narrow channel did not hamper lampreys or the other species. Greater water flow, and thereby greater immersion depth on the ramp, fostered passage for all species. Smaller-bodied individuals of creek chubs and white suckers performed best on the ramp. We showed that wetted ramps could be incorporated into fishways at low-head dams to aid the passage of smaller-bodied fishes while also blocking the spawning migration of adult sea lampreys.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141810993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of Ovarian Lipid Composition in the Largemouth Bronze Gudgeon (Coreius guichenoti) at Different Development Stages","authors":"Jian Zhu, Nanjun Hu, Yao Xiao, Xiaohong Lai, Lingjiao Wang, Yufeng Song","doi":"10.3390/fishes9070291","DOIUrl":"https://doi.org/10.3390/fishes9070291","url":null,"abstract":"The largemouth bronze gudgeon has experienced a sharp drop in its natural population and has been listed as a protected species in China. The frequent occurrence of ovarian development obstruction from stage III to IV has restricted artificial propagation. Due to lipids being a crucial factor for ovarian development, this study aimed to characterize the ovarian lipid profile at different development stages in largemouth bronze gudgeons. Using UPLC-MS/MS, 1353 lipids belonging to 46 subclasses were identified in ovaries from largemouth bronze gudgeons. The results showed that glycerolipids and glycerophospholipids were the dominant lipids during ovarian development. Lysophosphatidyl choline (LPC), phosphatidyl choline (PC), and phosphatidylserine (PS), as the crucial phospholipids for ovarian development, were significantly reduced from stage III to IV. This may be the main cause of ovarian development obstruction for largemouth bronze gudgeons. Meanwhile, the enrichment analysis revealed that lipid metabolites are present at different ovarian development stages. Glycerophospholipid, linoleic acid, and linolenic acid metabolism were significantly enriched at stage IV. This study shows the complete picture of the ovarian lipid composition profile, and also discovers that phospholipids may be the limiting factor for ovarian development; these findings offer a theoretical basis for the artificial propagation and release of the largemouth bronze gudgeon.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141817264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Practice of Territorial Use Rights in Fisheries in Coastal Fishery Management in China: A Case Study of the Island Reefs Fishery Lease Policy from Shengsi County in Zhejiang Province","authors":"Minsi Xiong, Zuli Wu","doi":"10.3390/fishes9070292","DOIUrl":"https://doi.org/10.3390/fishes9070292","url":null,"abstract":"Coastal fisheries are vital for food supply, employment, and social stability. However, overfishing is a common problem, often attributed to open access. Territorial Use Rights in Fisheries (TURFs) have gained popularity as a tool to improve the sustainability of coastal fisheries, but research on TURFs in China is limited. This paper examines the island reef fishery lease policy implemented in Shengsi County, Zhejiang Province, within the Ma’an Islands National Marine Special Reserve. The policy leases the use of island reefs to a collective, aiming to address overfishing and resource degradation by establishing fishing area boundaries and limiting the number of users and usage time. Technically, it is an application of TURFs, and it represents a shift from traditional fishing licenses to collective compliance. This experience has disrupted the existing top–down fishery governance structure and signifies a transition to a rights-based fishery management system in China. Through a comprehensive investigation and analysis of the policy’s implementation, this research identifies the factors contributing to its flaws. These include the inadequate provision of national and local government policies, insufficient support for policy implementation from fishery management authorities, and the limited involvement of fishermen’s organizations. To enhance coastal fishery management, we propose that the Chinese government should build upon existing foundations by clarifying fishing rights through central and local laws and policies. Additionally, there is a need to strengthen data monitoring of coastal fisheries, conduct multidisciplinary research to improve the allocation mechanism of fishing rights, adopt diverse fishery management approaches to enhance supervision capabilities, establish a collaborative governance mechanism, and foster coordination and cooperation between grassroots fishermen’s organizations and government departments.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141816960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Xenotransplantation of European Eel (Anguilla anguilla) Spermatogonia in Zebrafish (Danio rerio) and European Sea Bass (Dicentrarchus labrax)","authors":"M. Blanes-García, Z. Marinović, M. Morini, Alain Vergnet, Á. Horváth, J. Asturiano","doi":"10.3390/fishes9070290","DOIUrl":"https://doi.org/10.3390/fishes9070290","url":null,"abstract":"The European eel encounters challenges in achieving sexual maturation in captivity, which has been a concern for researchers. This study explores surrogate broodstock technology as an alternative approach for eel production. The present study aimed to evaluate zebrafish and European sea bass as potential recipients for European eel spermatogonia transplantation, given the abundance of eel type A spermatogonia (SPGA). Immature European eel testes were dissected and maintained at 4 °C or cryopreserved. SPGA were obtained by dissociation of fresh or post-thawed tissue, employing an enzymatic solution, and then labelled with fluorescent membrane marker PKH26. SPGA from fresh tissue were transplanted into wild-type zebrafish larvae and triploid European sea bass larvae, while SPGA from cryopreserved testis were transplanted into vasa::egfp transgenic zebrafish larvae. One-and-a-half months post-transplantation (mpt), fluorescent donor cells were not detected in the gonads of zebrafish or European sea bass. Molecular qPCR analyses at 1.5 or 6 mpt did not reveal European eel-specific gene expression in the gonads of any transplanted fish. The findings suggest that the gonadal microenvironments of zebrafish and European sea bass are unsuitable for the development of European eel spermatogonia, highlighting distinctive spermatogonial stem cell migration mechanisms within teleost species","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141817523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding the Causes of Lumpfish (Cyclopterus lumpus) Mortality in Norwegian Hatcheries: Challenges and Opportunities","authors":"Lauris Boissonnot, Camilla Karlsen, T. M. Jonassen, Silje Stensby-Skjærvik, Torolf Storsul, A. Imsland","doi":"10.3390/fishes9070288","DOIUrl":"https://doi.org/10.3390/fishes9070288","url":null,"abstract":"Lumpfish are broadly used as biological sea lice removers in Norwegian salmon farming and are mostly produced in hatcheries. To date, there is little systematic documentation on the mortality causes of lumpfish in hatcheries. In the current study, data from 12 selected fish groups from four hatcheries in Norway were collected to understand the challenges and opportunities related to the categorization of mortality causes of lumpfish in hatcheries. This study indicated that a high proportion of lumpfish mortality was categorized by the hatcheries as unspecified. When specified, mortality was primarily assessed as due to fin damage. Our analyses showed that mortality categorized as fin damage correlated with the detection of infectious agents in dead fish, suggesting that mortality was due to infections rather than fin damage. It was not possible to conclude whether infection with pathogens present in the environment caused fin damage or if injuries from aggression were a gateway for pathogens. Furthermore, due to the lack of information regarding production conditions, it was not possible to assess risk factors causing eventual aggression or the presence of pathogens. This study revealed that mortality causality—the chain of events leading to death—is mainly unclear in lumpfish hatcheries because (1) mortality categorization does not focus on underlying causes and (2) there is little documentation of production conditions, making it very difficult to relate mortality rates to external factors. The present findings highlight that there are gaps in the registrations made by hatcheries and that there is an urgent need to implement standardized monitoring protocols for lumpfish hatcheries. This will help identify the causes of mortality and, therefore, allow for the implementation of proper measures that will ensure better survival.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141823175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tracking Biomarkers for the Health and Welfare of Aquaculture Fish","authors":"Joana Oliveira, Aires Oliva‐Teles, Ana Couto","doi":"10.3390/fishes9070289","DOIUrl":"https://doi.org/10.3390/fishes9070289","url":null,"abstract":"Aquaculture production has been growing consistently over the last few decades to meet the increasing animal protein demand of the human population. However, increased production and rearing intensities raise the challenges of guaranteeing fish health and welfare, which is essential to avoid losses and ensure product quality. Biomarkers can provide insights into the fish’s nutritional, physiological, and health status, and aid in the evaluation of early nutritional and physiological imbalances, distress conditions, and pathological diagnosis. The discovery and validation of biomarkers rely mostly on the use of information provided by different parameters, including biochemical, metabolic, or immunologic, as well as several omics, from genomics and transcriptomics to proteomics and metabolomics. In this review, a summary of the main biomarkers used in aquaculture is provided along with an overview of the main omics technologies available for further biomarker research. This review also highlights the need to develop non-lethal biomarkers that can easily and quickly be measured to provide a prompt response to producers.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141823371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of Salt, Anesthetics, and Stocking Density in Transport of Live Fish: A Review","authors":"R. K. Luz, G. Favero","doi":"10.3390/fishes9070286","DOIUrl":"https://doi.org/10.3390/fishes9070286","url":null,"abstract":"For freshwater or marine fish farming to be successful, live fish must be transported. This can be performed with eggs, larvae, juveniles, and adults. Nonetheless, because of the handling, confinement, and duration of transport, it is considered a difficult procedure. To prevent significant physiological changes that could result in fish mortality, it is crucial to look for ways to reduce stress and enhance the quality of transport water. Consequently, a comprehensive range of research on the use of additives in water, including salt and artificial or natural anesthetics, is presented in this review, which also discusses potential changes in water quality factors during transport, such as dissolved oxygen (DO), carbon dioxide (CO2), pH, ammonia, and temperature. The usage of stocking densities during transport is also covered in this review, with consideration given to the various recommendations for each species, fish size, and length of transport.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141827928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sex Differences in the Brain Transcriptomes of Adult Blue Gourami Fish (Trichogaster trichopterus)","authors":"G. Degani, A. Meerson","doi":"10.3390/fishes9070287","DOIUrl":"https://doi.org/10.3390/fishes9070287","url":null,"abstract":"Blue gourami (gourami, Trichogaster trichopterus) is a model for labyrinth fishes (Anabantoidei) adapted to partial air breathing. Its reproductive endocrinology has been extensively studied, and transcriptomic sex differences in the gonads were described. Nevertheless, sex differences in gene expression in non-gonadal tissues ostensibly affected by the sex-specific hormonal balance, e.g., the brain, are unknown. To assess such differences, we used bulk RNA-seq to assemble and compare polyA+ transcriptomes between whole brains of four adult male and five adult female gourami, in addition to other tissues (three dorsal fin and five ovary samples) from the same female group. While all nine brain transcriptomes clustered together relative to the other tissues, they showed separation according to sex. A total of 3568 genes were differentially expressed between male and female brains; of these, 1962 and 1606 showed lower and higher expression in males, respectively. Male brains showed stronger down-regulation of specific genes, which included hormone receptors, e.g., pituitary adenylate cyclase-activating polypeptide receptor (pacap-r1). Among the genes with lower expression in male brains, multiple pathways essential to brain function were over-represented, including GABA, acetylcholine and glutamate receptor signaling, calcium and potassium transmembrane transport, and neurogenesis. In contrast, genes with higher expression in male brains showed no significant over-representation of brain-specific functions. To measure the mRNA levels of specific hormone receptors known from prior studies to regulate reproductive function and behavior in gourami and to validate RNA-seq results for these specific genes, we performed RT-qPCR for five receptors, pacap-r1, gonadotropin-releasing hormone 2 receptor (gnrh2r), kisspeptin receptor 1 (gpαr1/kiss1), insulin-like growth factor 1 receptor (igf1r), and membrane progesterone receptor 1 (mpr1), in the brain RNA sample groups. Of these, pacap-r1 showed a significant, three-fold down-regulation, while gpαr1/kiss1 showed a significant two-fold down-regulation in male vs. female gourami brains. Our results are novel in describing the suppression of brain function-related gene expression in male, as compared to female, gourami brains. Further research is needed to assess the behavioral significance of this effect and its prevalence in other vertebrate groups.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141824755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}