Volume 76, Issue 3, 2024

Permanent URI for this collection

Browse

Recent Submissions

Now showing 1 - 4 of 4
  • Item
    Effects of emodin on the physiological responses and antioxidant gene expression of Wuchang bream infected with Aeromonas hydrophila
    ( 2024) Zhang, Yuanyuan ; Lu, Hong ; Ke, Han ; Cheng, Hui-zhong ; Zhu, Yong-an ; Song, Li-ping ; Tian, Hong-yan ; Huang, Wen-wen
    This experiment aimed to investigate the effects of emodin on the physiological responses and antioxidant gene expression of Wuchang bream infected with Aeromonas hydrophila. The experimental diets were prepared with supplementing 0, 30, 100 and 150 mg kg−1 emodin to basal (control) diet respectively, and fed to fish with initial weight of 50.4 ± 2.35 g. All fish were divided into five experimental groups: uninfected fish fed with basal control diet (negative control, NC), infected fish fed with the diet supplemented with 0 (positive control group, PC), 30, 100, and 150 mg kg-1 emodin. The fish were reared for 14 days, sampled at different time points and then analyzed. The results showed that the physiological responses and related antioxidant gene expression of infected Wuchang bream were significantly influenced by the dosage of added emodin and the feeding duration (P < 0.05). Comparing to the positive control group, emodin could inhibit the levels of cortisol (COR), triiodothyronine (T3), and thyroxine (T4) in infected Wuchang bream, with hormone levels reaching equilibrium in the shortest time at 30 and 100 mg kg-1 emodin supplementation. Meanwhile, emodin significantly affected alkaline phosphatase (AKP) activity, glucose (Glu) and triglyceride (TG) contents, and related antioxidant gene expression in infected Wuchang bream (P < 0.05), with the best effect observed at 100 mg kg-1 emodin supplementation in the diet. In conclusion, the supplementation of 100 mg/kg emodin to diet can enhance the resistance of Wuchang bream to A. hydrophila infection via promoting physiological metabolism and antioxidant capacity.
  • Item
    The diffusion path and influencing factors of shrimp farming technology
    ( 2024) Jin, Hongtao ; Xiang, Lele ; Chen, Fang ; Zhu, Wenjun
    Aquatic products have played an increasingly important role in residents' diets, with improved production capacity and living standards in recent years. Accelerating the organic diffusion of aquaculture technology is an effective way to increase production. Taking the example of South American white shrimp aquaculture, this article combines carbon emissions and aquaculture cost benefits. By using data from South American white shrimp aquaculture in Hebei, Shandong, and Jiangsu Province in China from 2016 to 2021, the article innovatively considers aquaculture cycle carbon emissions as non-expected output, constructs a non-expected SBM-DEA super-efficiency model to evaluate the comprehensive efficiency of two aquaculture technologies, and analyzes the influencing factors of the diffusion of shrimp culture technology through case studies. The research results show that the comprehensive efficiency of factory-based aquaculture technology is generally better than pond-based aquaculture, but carbon emissions are higher in the factory model. The main factors affecting the diffusion of factory-based technology are policy support, social networks, farmers' own situations, and technological attributes.
  • Item
    Cloning and expression patterns of espl1 gene in loach (Misgurnus anguillicaudatus) during gonad development
    ( 2024) Jiang, Hanjun ; Huang, Qianqian ; Guo, Xusheng ; Liu, Jiahui ; Feng, Dexiang ; Cao, Xiaojuan
    espl1 (extra spindle pole bodies like 1), a cysteine endopeptidase, is a mitotic key player in chromosomal segregation and centriole duplication during mitosis and meiosis. Considering the espl1 gene has not been reported in aquatic organisms, we reported the isolation and expression of the espl1 gene from loach. In this study, the full-length cDNA of espl1 was cloned for the first time in loach. In loach, the full-length cDNA of espl1 consisted of 6948 bp, the open reading frame (ORF) is 6240 bp, and the espl1 gene encodes 2139 amino acids. Moreover, the deduced amino acid sequences of espl1 in loach shared the highest identity with those of Cyprinus carpio (78.39%) and Sinocyclocheilus anshuiensis (78.27%), and the sequence homology among the various separases is confined to the C-terminal region. Furthermore, tissue-specific checking results indicated that the espl1 gene of the loach gene was highly expressed in the ovary and testis, especially in stage IV oocytes and stage IV testis by Real-time quantitative PCR (qPCR). Then, whole-mount in situ hybridization analyses revealed the expression of espl1 in the early development of loach. We found that the positive signal of espl1 was observed in the notochord during the early embryo development of loach. Last but not least, when treated with luteinizing hormone-releasing hormone analog (LHRH-A2), the mRNA expression of espl1 was significantly increased in the testes and ovaries. These observations suggest that the espl1 gene had a distinct and important role in the gonads of Loach. This study will be of value for further studies into the function of the espl1 gene in fish.
  • Item
    Characteristics of surface flow field and substrate in the spawning ground of Schizothorax grahami
    ( 2024) Xu, Li ; Zhou, Yang ; Cui, Weijie ; Lu, Qun ; Liu, Jianhu ; Duan, Cong ; He, Tao
    The Spawning ground is a crucial habitat for fish, and the physical characteristics of the habitat are important for fish life history. In this paper, Large-Scale Particle Image Velocimetry (LSPIV) was used to measure the surface flow field and the substrate (particle size and mineral composition) in the spawning ground of Schizothorax grahami. Based on the literature and consideration of experimental feasibility, two spawning grounds in the source of the Chishui River were selected—Erlongqiangbao (located in the mainstream) and Bamaoba (located in the tributary), two and three cross sections of each river section were analyzed respectively. The results show that Erlongqiangbao first flows in the direction of "southeast-northwest" and then "southwest—northeast" after crossing the bridge; the maximum velocity of the reach is 3.374m/s. The size of the substrate is mainly less than 1mm in the upstream section of Erlongqiangbao, both 25-50mm in the middle and downstream, and the substrate type mainly is quartz and calcite; Gushangtian flows in the direction of "southwest-northeast," the maximum velocity of the reach is 1.537m/s, the size of the substrate is mainly greater than 50mm in the upstream, and 25-50mm in the middle and downstream, the substrate type mainly is quartz, calcite, and dolomite. The mineral compositions of the two spawning sites were analyzed by principal component analysis. Quartz and anorthose are more than 1 in composite scores, respectively ranked first and second, indicating that they play a dominant role in the mineral composition. This study could provide basic data and ideas for restoring S. grahami spawning ground.