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Recent Submissions
Dietary incorporation of Bacillus subtilis, enhances growth performance, survival rate, gametogenesis and intestinal health, in zebrafish (Danio rerio)
(2025) Dede, Kemal; Cek, Sehriban
This study assessed the probiotic effects of dietary supplementation with Bacillus subtilis HBB 493® on growth, survival, gametogenesis, and intestinal health of Zebrafish (Danio rerio). 600 juveniles were divided into five experimental groups namely: Control group I (0.0 cfu/g), group II (6.5x109 cfu/g), group III (1.3x1010 cfu/g), group IV (2.6x1010 cfu/g) and group V(3.9x1010 cfu/g). Each treatment and control had three replicates, while each replicate had 40 fish. The duration of the experiment was 100 days. At the termination of the experiment, gonads, and intestine were histologically assessed. Growth parameters, in the fish fed 3.9x10^10^ cfu/g were significantly different from those observed in the control, group II, and group III B. subtilis fed groups (P<0.05), and group V was the best. There were no significant differences in the survival rate between treatment groups including control (P>0.05). The histological observations of the gonads reveal differences among the fish fed different levels of B. subtilis. Fish fed diets II, III, IV and V had more developed gonads compared to those on diets without B. subtilis. The status of villus and goblet cells was used to assess the intestinal health of the fish fed diets supplemented with B. subtilis. Villus and goblet cells were intact in all the different levels of B. subtilis supplemented groups. The present study suggested that the dietary supplementation of 3.9x1010 cfu/g probiotic B. subtilis should be used for the enhancement of growth parameters, survival rate, gametogenesis and intestinal health in ornamental zebrafish.
Effect of chronic heat stress in roughskin sculpin (Trachidermus fasciatus)
(2025) Liu, Zitong; San, Lize; He, Zhongwei; Liu, Yufeng; Han, Tian; Gong, Chunguang; Ren, Jiangong; Ren, Yuqin; Hou, Jilun
The roughskin sculpin (Trachidermus fasciatus) belongs to the family Cottidae and is a small carnivorous catadromous fish distributed along the coasts of China, Korea, and Japan. The effects of heat stress on roughskin sculpin have yet to be systematically performed. This study aimed to explore the effects of chronic heat stress on the roughskin sculpin. The survival rate, gill histopathological changes, and heat stress protein gene expression patterns of roughskin sculpin were analyzed after different temperature stresses of 19 ℃, 22 ℃, 25 ℃, 28 ℃, and 31 ℃ for 0, 3, 6, 9, and 12 days. The results revealed that roughskin sculpin could not survive at 33 ℃. Chronic heat stress can cause severe damage to gill tissue, reducing the gills' respiratory efficiency. Moreover, the expressions of hspb1, hspb7, and hspb11 changed significantly after heat stress. In the 31 ℃ treatment group, as stress time increased, hspb1, hspb7, and hspb11 expression initially increased and then decreased. This study’s results provide a reference for the study of heat stress physiology of roughskin sculpin as well as a new idea and method for evaluating and breeding heat stress traits of roughskin sculpin.
Supplementation of Yellow River carp diet with lutein and ferrous fumarate: Growth performance, digestive enzyme activity, skin pigmentation, and intestinal microbiota
(2025) Ren, Hongtao; Cao, Xiang; Guo, Xiangzhi; Yuan, Peng
In this study, the effect of the diet with lutein and ferrous fumarate on Yellow River carp (Cyprinus carpio) was studied, aiming to evaluate skin pigmentation, intestinal digestive enzymes, intestinal microbial diversity, and growth performance. Three experimental diets, including a control group, a lutein group (150mg/kg lutein), and a lutein and ferrous fumarate mixture group (150mg/kg lutein and 100mg/kg ferrous fumarate), were designed. The carp (N=135; 25.0±2.0g) were fed with experimental diets for 42 days. The results showed that the intestosomatic index (ISI) and viscerosomatic index (VSI) of the carp fed with lutein and ferrous fumarate were increased, accompanied by significant changes in body color, with the higher value of blue (b), color difference (ΔE) and chroma (Ch) compared with control group (P <0.05). Meanwhile, the higher activity of amylase, lipase, and trypsin were observed in the mixture group (P<0.05). High-throughput sequencing and Venn diagrams revealed that lutein or ferrous fumarate has obvious effects on the intestinal microbiota community of carp. The abundance of Actinobacteria and Flavobacterium was significantly increased in the carp fed with the mixture group compared with the control group. In conclusion, the addition of lutein and ferrous fumarate to the feed can change the skin pigmentation and intestinal microbial composition of Yellow River carp, thereby enhancing the coloring effect and digestive function of the fish. These findings provide valuable insights for optimizing feed formulation and aquaculture management, which can contribute to the improvement of the quality and farming efficiency of Yellow River carp.
Identification and characterization of tissue-specific genes in response to handling stress in topmouth culter (Culter alburnus) kidney, liver and muscle tissues
(2024) Chi, Meili; Cheng, Shun; Zheng, Jianbo; Liu, Shili; Jiang, Wenping; Li, Fei
Topmouth culter (Culter alburnus) is China's important freshwater economic fish. However, external stressors frequently provoke intense responses, leading to low survival rates and diminished productivity. The absence of stress-related genes has significantly limited our understanding of stress response in this fish. Therefore, 85,846,206 high-quality reads were acquired from kidney, liver, and muscle cDNA libraries of topmouth culter using Illumina sequencing technology in this study. Comparative analysis revealed that 3,158, 409, and 1,952 unigenes were specifically expressed in the kidney, liver, and muscle transcriptome. Additionally, 83 crucial tissue-specific genes were identified within three stress-related GO terms: response to stimulus (GO:0050896), response to stress (GO:0006950) and response to hypoxia (GO:0001666). From these, 18 tissue-specific genes were further isolated. During the short-term stress experiment (two repeated handling stress, including chasing 2 min and netting out of water for 30 sec), significant changes were observed in the cortisol levels of both the treatment and recovery groups. Furthermore, notable changes were noted in the expression of LCP2, PTK2b, and P-selectin genes in the kidney; FABP1, IGFBP1, and CYP4V2 genes in the liver; and MYH10, Myogenin 2 and Troponin C genes in the muscle of topmouth culter in the treatment and recovery groups (P \< 0.05). The tissue-specific transcriptome profiles generated in this study offer valuable insights into the molecular and functional mechanisms associated with stress response in topmouth culter. We characterized genes related to stress response in tissues such as the kidney, liver, and muscle; these findings offer novel insights into stress research in fish. We can further explore the breeding of strains with enhanced stress resistance and promote the healthy development of topmouth culter industry.
Application of Improved YOLOv8n-seg in Crayfish Trunk Segmentation
(2024) Geng, Chunxin; Wang, Aimin; Yang, Cheng; Xu, Zhiqiang; Xu, Yu; Liu, Xingguo; Zhu, Hao
The crayfish industry (Procambarus clarkii) is experiencing rapid growth. However, the processing sector continues to face challenges due to a lack of advanced automation, relying heavily on manual visual inspection to assess crayfish specifications and integrity, which limits efficiency and precision in decision-making. To address the issue of intelligent grading of P. clarkii, this work proposes the GHB-YOLOv8-seg algorithm for segmenting the main trunk of P. clarkii shrimp based on the YOLOv8n-seg model. The original main trunk network is replaced through the coupling of Ghost and HGNetV2, and depth-separable convolution is employed to perform the linear transformation of the features. This results in a reduction in the number of parameters and computational complexity while maintaining high accuracy. The computational complexity is reduced; concurrently, introducing the weighted bidirectional feature pyramid network (BiFPN) enables the model to perform multi-scale feature fusion with greater alacrity, thereby enhancing the model's performance. Ultimately, the intelligent grading of crayfish specifications was achieved by calculating the pixel area after segmentation and converting it to the actual body weight. The results demonstrated that the number of parameters of the improved YOLOv8n-seg model was reduced by 60.5%, the model size was reduced by 55.4%, and the mAP value was increased from 98.9% to 99.2%. The study indicates that the YOLOv8n-seg algorithm model facilitates precise and lightweight segmentation of the crayfish trunk, which can be integrated into diverse mobile devices.