Comprehending the spatial distribution of human fishing endeavors holds significant importance in the context of monitoring fishery resources and implementing spatial management measures. To gain insights into the spatial arrangement of tuna longline activities within the exclusive economic zones of Tonga and their correlation with the marine environment, this study utilizes data from the Tonga Tuna Longline Fisheries spanning from 2002 to 2018. The data are employed to extract information about the spatial distribution of fishing efforts and coupled with 15 marine environmental variables covering both sea surface and subsurface conditions. This study employs boosted regression trees (BRT) and general additive models (GAM) to establish the non-linear relationships between the distribution of fishing effort and marine environmental factors. Furthermore, it examines and analyzes the ecological niche occupied by tuna longline vessels in high-sea environments. The outcomes of the factor analysis indicate that the most important factors influencing the fishing efforts of tuna longliners are the dissolved oxygen content at the sea surface and latitude. These two factors contribute significantly, accounting for 19.06% and 18.62% of the fishing efforts of vessels, respectively, followed by distance to ports, longitude, and dissolved oxygen at 100 m depth, contributing 10.77%, 7.07%, and 6.30%, respectively. The sea surface chlorophyll, ocean current at 100 m depth, and mixed layer depth contributed the least, 3.63%, 2.13%, and 1.72, respectively. In terms of space and time, tuna longliners are more likely to operate in the 18–22° S latitudinal and 172–178° W longitudinal region, and fishing efforts increased in the months from March to August. The spatial distribution of the fishing efforts modeled for fishing vessels in 2018 is predicted to have good spatial distribution with the actual fishing efforts of these vessels. This research aids in comprehending the environmental impacts resulting from shifts in the spatial distribution of tuna longline vessels, offering valuable insights for the effective management of tuna longline fisheries in Tonga.
{"title":"Environmental Factors Determine Tuna Fishing Vessels’ Behavior in Tonga","authors":"Siosaia Vaihola, Stuart Kininmonth","doi":"10.3390/fishes8120602","DOIUrl":"https://doi.org/10.3390/fishes8120602","url":null,"abstract":"Comprehending the spatial distribution of human fishing endeavors holds significant importance in the context of monitoring fishery resources and implementing spatial management measures. To gain insights into the spatial arrangement of tuna longline activities within the exclusive economic zones of Tonga and their correlation with the marine environment, this study utilizes data from the Tonga Tuna Longline Fisheries spanning from 2002 to 2018. The data are employed to extract information about the spatial distribution of fishing efforts and coupled with 15 marine environmental variables covering both sea surface and subsurface conditions. This study employs boosted regression trees (BRT) and general additive models (GAM) to establish the non-linear relationships between the distribution of fishing effort and marine environmental factors. Furthermore, it examines and analyzes the ecological niche occupied by tuna longline vessels in high-sea environments. The outcomes of the factor analysis indicate that the most important factors influencing the fishing efforts of tuna longliners are the dissolved oxygen content at the sea surface and latitude. These two factors contribute significantly, accounting for 19.06% and 18.62% of the fishing efforts of vessels, respectively, followed by distance to ports, longitude, and dissolved oxygen at 100 m depth, contributing 10.77%, 7.07%, and 6.30%, respectively. The sea surface chlorophyll, ocean current at 100 m depth, and mixed layer depth contributed the least, 3.63%, 2.13%, and 1.72, respectively. In terms of space and time, tuna longliners are more likely to operate in the 18–22° S latitudinal and 172–178° W longitudinal region, and fishing efforts increased in the months from March to August. The spatial distribution of the fishing efforts modeled for fishing vessels in 2018 is predicted to have good spatial distribution with the actual fishing efforts of these vessels. This research aids in comprehending the environmental impacts resulting from shifts in the spatial distribution of tuna longline vessels, offering valuable insights for the effective management of tuna longline fisheries in Tonga.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":"24 1","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138592493","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}
Amanda Cohen-Sánchez, Antoni Gabriel Sánchez-Mairata, J. M. Valencia, A. Box, S. Pinya, S. Tejada, Antoni Sureda
Global change produces substantial modification to the distribution and rhythm of infection of diseases in fish, favouring the introduction of new pathogens. Recently, the presence of black spot disease, associated with a digenean fluke of the genus Scaphanocephalus, has been observed in specimens of Xyrichthys novacula on the island of Ibiza (Balearic Islands). The aim of the present study was to evaluate the antioxidant and immune response in both the skin mucus and spleen of X. novacula depending on the degree of infection by Scaphanocephalus sp. The specimens were captured in a control area, without the presence of the parasite, and in an affected area, classifying the fish as low infection (1–15 spots) and high infection (>15 spots). As the degree of infection increased, a decrease in the body condition index was observed. The activity of the antioxidant enzymes in the mucus—catalase, superoxide dismutase and glutathione peroxidase—increased progressively with the degree of infection. This activation of antioxidant defences was not enough to prevent an increase in malondialdehyde levels, an indicator of oxidative damage, in the group with the highest infection. Similarly, an increase in immunological parameters—lysozyme, alkaline phosphatase, myeloperoxidase and immunoglobulins—was observed in mucus as infection increased. Regarding the spleen, only an increase in lysozyme activity and alkaline phosphatase in fish with a greater severity of infection was observed. In conclusion, as the severity of Scaphanocephalus sp. infection increased, it induced an immune and oxidative stress response in skin mucus, leading to a decrease in overall body condition. The potential health effects that the ectoparasite may have on X. novacula populations will require follow-up studies.
{"title":"Immune and Oxidative Stress Response of the Fish Xyrichthys novacula Infected with the Trematode Ectoparasite Scaphanocephalus sp. in the Balearic Islands","authors":"Amanda Cohen-Sánchez, Antoni Gabriel Sánchez-Mairata, J. M. Valencia, A. Box, S. Pinya, S. Tejada, Antoni Sureda","doi":"10.3390/fishes8120600","DOIUrl":"https://doi.org/10.3390/fishes8120600","url":null,"abstract":"Global change produces substantial modification to the distribution and rhythm of infection of diseases in fish, favouring the introduction of new pathogens. Recently, the presence of black spot disease, associated with a digenean fluke of the genus Scaphanocephalus, has been observed in specimens of Xyrichthys novacula on the island of Ibiza (Balearic Islands). The aim of the present study was to evaluate the antioxidant and immune response in both the skin mucus and spleen of X. novacula depending on the degree of infection by Scaphanocephalus sp. The specimens were captured in a control area, without the presence of the parasite, and in an affected area, classifying the fish as low infection (1–15 spots) and high infection (>15 spots). As the degree of infection increased, a decrease in the body condition index was observed. The activity of the antioxidant enzymes in the mucus—catalase, superoxide dismutase and glutathione peroxidase—increased progressively with the degree of infection. This activation of antioxidant defences was not enough to prevent an increase in malondialdehyde levels, an indicator of oxidative damage, in the group with the highest infection. Similarly, an increase in immunological parameters—lysozyme, alkaline phosphatase, myeloperoxidase and immunoglobulins—was observed in mucus as infection increased. Regarding the spleen, only an increase in lysozyme activity and alkaline phosphatase in fish with a greater severity of infection was observed. In conclusion, as the severity of Scaphanocephalus sp. infection increased, it induced an immune and oxidative stress response in skin mucus, leading to a decrease in overall body condition. The potential health effects that the ectoparasite may have on X. novacula populations will require follow-up studies.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":"43 3","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138596555","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}
Samuel J. Johnston, Jason B. Smith, Brady D. Slater, J. Doubek
Ecosystem alterations to Lake Michigan (LM), such as the invasion of dreissenid mussels, have decreased the abundance of phytoplankton and, subsequently, zooplankton, which has implications for Great Lake fisheries. The community composition of zooplankton has also been altered over the past 20 years in LM, shifting the summer dominance from cladoceran to calanoid taxa. However, most of our information on zooplankton community dynamics is from deeper pelagic zones. The nearshore beach (≤1 m) habitat, which serves as a critical nursery for some larvae and juvenile fish, is composed of different zooplankton taxa than deeper zones, but limited data are available for comparison. We conducted a standardized summer sampling campaign to characterize the zooplankton community across 32 beaches in LM. We found the lowest crustacean zooplankton density and biomass on northern LM beaches and a higher zooplankton density and biomass on Greater Green Bay and central LM beaches, which had warmer water temperatures. Smaller-bodied cladocera (mainly Bosmina) and cyclopoid taxa were the most abundant groups on beaches. Our results provide the first comprehensive characterization of zooplankton on beaches in the Great Lakes, with applications for other lake systems. These results may help identify potential “hot spots” of fish recruitment for management.
{"title":"Spatial Density, Biomass, and Composition of Crustacean Zooplankton on Lake Michigan Beaches","authors":"Samuel J. Johnston, Jason B. Smith, Brady D. Slater, J. Doubek","doi":"10.3390/fishes8120599","DOIUrl":"https://doi.org/10.3390/fishes8120599","url":null,"abstract":"Ecosystem alterations to Lake Michigan (LM), such as the invasion of dreissenid mussels, have decreased the abundance of phytoplankton and, subsequently, zooplankton, which has implications for Great Lake fisheries. The community composition of zooplankton has also been altered over the past 20 years in LM, shifting the summer dominance from cladoceran to calanoid taxa. However, most of our information on zooplankton community dynamics is from deeper pelagic zones. The nearshore beach (≤1 m) habitat, which serves as a critical nursery for some larvae and juvenile fish, is composed of different zooplankton taxa than deeper zones, but limited data are available for comparison. We conducted a standardized summer sampling campaign to characterize the zooplankton community across 32 beaches in LM. We found the lowest crustacean zooplankton density and biomass on northern LM beaches and a higher zooplankton density and biomass on Greater Green Bay and central LM beaches, which had warmer water temperatures. Smaller-bodied cladocera (mainly Bosmina) and cyclopoid taxa were the most abundant groups on beaches. Our results provide the first comprehensive characterization of zooplankton on beaches in the Great Lakes, with applications for other lake systems. These results may help identify potential “hot spots” of fish recruitment for management.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":"38 15","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138597565","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}
Yingming Yang, Wenlong Li, Run Wang, Dan Xu, Yadong Chen, Zhongkai Cui, Songlin Chen
Massive macroalgae blooms, primarily caused by the overgrowth of Ulva prolifera (U. prolifera) in the Yellow Sea of China, pose a severe risk to both marine organisms and the aquaculture industry. This study’s aim was to evaluate the impact of U. prolifera degradation on the growth performance and antioxidant capacity of Japanese flounder (Paralichthys olivaceus) and select some potential Japanese flounder families (labeled 2101–2108, established by crossbreeding) tolerating U. prolifera degradation conditions. Thus, a 60-day U. prolifera exposure experiment was conducted. The results showed that the contents of Na, K, Mg, and Fe elements in the U. prolifera degradation water were significantly increased. The specific growth rate and survival rate of flounder were significantly decreased under the U. prolifera degradation condition, while the 2101 and 2103 flounder families showed a better growth performance compared with the positive control (PC) group. Moreover, the results showed that activities of total antioxidant capacity (T-AOC), transaminases, and alkaline phosphatase (AKP) in serum were significantly decreased, while the 2103 flounder family showed higher activities. Furthermore, U. prolifera degradation significantly increased superoxide dismutase (SOD) activity and glutathione (GSH) content while decreasing catalase (CAT) activity and malondialdehyde (MDA) content in the liver. Specifically, SOD and CAT activities of the 2103 flounder family were higher than the 2101 flounder family and PC group. In addition, the gill SOD and CAT activities of the 2103 flounder family were significantly higher than the PC group. Similarly, the antioxidant-related gene (sod and cat) expressions were synchronously upregulated or downregulated in the liver and gills in response to U. prolifera degradation. These results revealed that U. prolifera degradation decreased the growth performance and influenced the antioxidant capacity of Japanese flounder, while the 2103 flounder family had better advantages in the U. prolifera degradation condition. Therefore, the 2103 flounder family could be regarded as the potential flounder family tolerating U. prolifera degradation. The increased Fe content in the U. prolifera degradation water may be one of the main causes of the physiological alterations observed in Japanese flounder.
{"title":"Effects of Ulva prolifera Degradation on Growth Performance and Antioxidant Capacity of Japanese Flounder (Paralichthys olivaceus) Family","authors":"Yingming Yang, Wenlong Li, Run Wang, Dan Xu, Yadong Chen, Zhongkai Cui, Songlin Chen","doi":"10.3390/fishes8120598","DOIUrl":"https://doi.org/10.3390/fishes8120598","url":null,"abstract":"Massive macroalgae blooms, primarily caused by the overgrowth of Ulva prolifera (U. prolifera) in the Yellow Sea of China, pose a severe risk to both marine organisms and the aquaculture industry. This study’s aim was to evaluate the impact of U. prolifera degradation on the growth performance and antioxidant capacity of Japanese flounder (Paralichthys olivaceus) and select some potential Japanese flounder families (labeled 2101–2108, established by crossbreeding) tolerating U. prolifera degradation conditions. Thus, a 60-day U. prolifera exposure experiment was conducted. The results showed that the contents of Na, K, Mg, and Fe elements in the U. prolifera degradation water were significantly increased. The specific growth rate and survival rate of flounder were significantly decreased under the U. prolifera degradation condition, while the 2101 and 2103 flounder families showed a better growth performance compared with the positive control (PC) group. Moreover, the results showed that activities of total antioxidant capacity (T-AOC), transaminases, and alkaline phosphatase (AKP) in serum were significantly decreased, while the 2103 flounder family showed higher activities. Furthermore, U. prolifera degradation significantly increased superoxide dismutase (SOD) activity and glutathione (GSH) content while decreasing catalase (CAT) activity and malondialdehyde (MDA) content in the liver. Specifically, SOD and CAT activities of the 2103 flounder family were higher than the 2101 flounder family and PC group. In addition, the gill SOD and CAT activities of the 2103 flounder family were significantly higher than the PC group. Similarly, the antioxidant-related gene (sod and cat) expressions were synchronously upregulated or downregulated in the liver and gills in response to U. prolifera degradation. These results revealed that U. prolifera degradation decreased the growth performance and influenced the antioxidant capacity of Japanese flounder, while the 2103 flounder family had better advantages in the U. prolifera degradation condition. Therefore, the 2103 flounder family could be regarded as the potential flounder family tolerating U. prolifera degradation. The increased Fe content in the U. prolifera degradation water may be one of the main causes of the physiological alterations observed in Japanese flounder.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":"5 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138600935","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}
Mathias Schakmann, Emil Aputsiaq Flindt Christensen, J. Steffensen, Morten Bo Søndergaard Svendsen
In the context of global warming and the concurrent decrease in ectothermic fish body size, the mechanisms driving this phenomenon remain a subject of scientific debate. This study, utilizing the Atlantic cod (Gadus morhua) as a model organism, delves into the behavioral size-dependent temperature preference in the context of climate change. A significant negative correlation between temperature preference and fish size was discovered, aligning with in situ habitat temperatures and optimal physiological performance metrics from other studies. This correlation suggests that larger fish exhibit a behavioral preference for colder areas, potentially leading to shifts in distribution toward polar regions or deeper waters in response to local global warming. The findings contribute to predictions of species distribution shifts, emphasizing the critical role of size-dependent temperature preference in shaping fish populations and offering valuable insights for conservation efforts. Additionally, the study uncovers a noteworthy relationship between body size and thermal safety margins in fish behavior, providing a novel avenue for future research into the intricate dynamics of thermal regulation in response to climate change. Overall, this research enhances our understanding of the complex interplay between temperature, fish size, and ecological responses, offering crucial information for informed conservation and management strategies.
{"title":"The Influence of Body Size on Behavioral Thermal Preference in Atlantic Cod (Gadus morhua): Larger Fish Favor Colder Waters","authors":"Mathias Schakmann, Emil Aputsiaq Flindt Christensen, J. Steffensen, Morten Bo Søndergaard Svendsen","doi":"10.3390/fishes8120596","DOIUrl":"https://doi.org/10.3390/fishes8120596","url":null,"abstract":"In the context of global warming and the concurrent decrease in ectothermic fish body size, the mechanisms driving this phenomenon remain a subject of scientific debate. This study, utilizing the Atlantic cod (Gadus morhua) as a model organism, delves into the behavioral size-dependent temperature preference in the context of climate change. A significant negative correlation between temperature preference and fish size was discovered, aligning with in situ habitat temperatures and optimal physiological performance metrics from other studies. This correlation suggests that larger fish exhibit a behavioral preference for colder areas, potentially leading to shifts in distribution toward polar regions or deeper waters in response to local global warming. The findings contribute to predictions of species distribution shifts, emphasizing the critical role of size-dependent temperature preference in shaping fish populations and offering valuable insights for conservation efforts. Additionally, the study uncovers a noteworthy relationship between body size and thermal safety margins in fish behavior, providing a novel avenue for future research into the intricate dynamics of thermal regulation in response to climate change. Overall, this research enhances our understanding of the complex interplay between temperature, fish size, and ecological responses, offering crucial information for informed conservation and management strategies.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":"76 17","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138606366","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}
Photoperiod is one of the most important environmental cues for organisms, and it plays a crucial role in regulating feeding, behavior, growth, and metabolism. However, seasonal photoperiods are often overlooked in carp culture or experiments, with a poorly understood effect on lipid metabolism and oxidative stress in fish. To explore the effects of seasonal photoperiods, we exposed Huanghe carp (Cyprinus carpio haematopterus) to summer photoperiod (14 h light:10 h dark) and winter photoperiod (10 h light:14 h dark) daylight conditions in an eight-week experiment. Our results suggested that the winter photoperiod significantly increased the liver TG level as well as the transcript levels of genes related to lipid synthesis, indicating that the lipid metabolism in Huanghe carp liver was enhanced compared to summer photoperiod conditions, and that lipid deposition may be responsible for the increase in body weight level and hepatosomatic index. Additionally, MDA, GSH, GSH-PX, and T-AOC levels were significantly elevated in the liver of fish under the winter photoperiod, suggesting that Huanghe carp responded to winter photoperiod exposure-induced oxidative stress in the liver by enhancing the antioxidant response. Based on transcriptome analysis, the winter photoperiod activated hepatic autophagy response and the FOXO signaling pathway in Huanghe carp. Combined with the correlation analysis, the Huanghe carp maintains the physiological health of the liver by activating the FOXO signaling pathway-mediated cell cycle regulation and autophagy response in response to oxidative stress during winter photoperiod exposure. Our study provides the first evidence for the physiological regulation of the liver in Huanghe carp under seasonal photoperiod stimulation.
{"title":"Effects of Seasonal Photoperiod on Growth, Lipid Metabolism, and Antioxidant Response in the Huanghe Carp (Cyprinus carpio haematopterus)","authors":"Wenqian Wang, Shengyan Su, Ping Dong, Wenrong Feng, Jianlin Li, Chengfeng Zhang, Yongkai Tang","doi":"10.3390/fishes8120595","DOIUrl":"https://doi.org/10.3390/fishes8120595","url":null,"abstract":"Photoperiod is one of the most important environmental cues for organisms, and it plays a crucial role in regulating feeding, behavior, growth, and metabolism. However, seasonal photoperiods are often overlooked in carp culture or experiments, with a poorly understood effect on lipid metabolism and oxidative stress in fish. To explore the effects of seasonal photoperiods, we exposed Huanghe carp (Cyprinus carpio haematopterus) to summer photoperiod (14 h light:10 h dark) and winter photoperiod (10 h light:14 h dark) daylight conditions in an eight-week experiment. Our results suggested that the winter photoperiod significantly increased the liver TG level as well as the transcript levels of genes related to lipid synthesis, indicating that the lipid metabolism in Huanghe carp liver was enhanced compared to summer photoperiod conditions, and that lipid deposition may be responsible for the increase in body weight level and hepatosomatic index. Additionally, MDA, GSH, GSH-PX, and T-AOC levels were significantly elevated in the liver of fish under the winter photoperiod, suggesting that Huanghe carp responded to winter photoperiod exposure-induced oxidative stress in the liver by enhancing the antioxidant response. Based on transcriptome analysis, the winter photoperiod activated hepatic autophagy response and the FOXO signaling pathway in Huanghe carp. Combined with the correlation analysis, the Huanghe carp maintains the physiological health of the liver by activating the FOXO signaling pathway-mediated cell cycle regulation and autophagy response in response to oxidative stress during winter photoperiod exposure. Our study provides the first evidence for the physiological regulation of the liver in Huanghe carp under seasonal photoperiod stimulation.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":"106 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138608520","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}
Jing Xu, Gangfu Chen, Min Wu, Qihui Yang, Hua-Tao Li
In this study, a linoleic and linolenic acid were incubated with petroleum ether extract, ethyl acetate extract, acetone extract (AE) and aqueous extract of Astragalus membranaceus. The phenolic content and total antioxidant capacity (T-AOC) were determined in the extracts of Astragalus membranaceus (EAms) above. Results showed that EAms decreased the levels of malonaldehyde, conjugated diene, and peroxide value levels in material above. Of all of EAms, AE showed the strongest T-AOC and inhibitory effect on the lipid oxidation. Next, fish feeds were incubated with graded levels of AE. The results showed that AE inhibited lipid oxidation in fish feed. The appropriate dosage for reducing lipid oxidation was 6.74 g AE kg−1 feeds. The effect of EAms on the lipid oxidation may be closely associated with their phenolic content. Then, juvenile Jian carp (Cyprinus carpio var. Jian, 10.2 ± 0.3 g) were fed with diets containing graded levels of AE (0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, and 7.0 g kg−1) for 60 days. Current data displayed that dietary AE increased the growth performance of fish. The optimum dosage for growth promotion was 5.15 g AE kg−1 diet. This result of AE may be ascribed to its enhancing effect on the activity of digestive and absorptive enzymes and antioxidant capacity in digestive organs of fish. Our present study indicated that EAm holds promise as a natural antioxidant for fish and their feed.
以黄芪的石油醚浸出物、乙酸乙酯浸出物、丙酮浸出物(AE)和水浸出物为原料,对亚油酸和亚麻酸进行培养。测定了黄芪提取物的酚类物质含量和总抗氧化能力。结果表明,EAms降低了上述材料中丙二醛、共轭二烯和过氧化值的水平。在所有eam中,AE对T-AOC和脂质氧化的抑制作用最强。然后,用AE分级孵育鱼饲料。结果表明,AE能抑制鱼饲料中的脂质氧化。降低脂质氧化的适宜投加量为6.74 g AE kg - 1饲料。eam对脂质氧化的影响可能与其酚类含量密切相关。分别饲喂AE水平为0.0、1.0、2.0、3.0、4.0、5.0、6.0和7.0 g kg−1的饲料,饲喂饲料60 d。目前的数据显示,饲料中AE提高了鱼的生长性能。促进生长的最佳投加量为5.15 g AE kg−1日粮。AE的这一结果可能与其对鱼类消化器官中消化吸收酶活性和抗氧化能力的增强有关。我们目前的研究表明,EAm有望成为鱼类及其饲料的天然抗氧化剂。
{"title":"The Extract of Astragalus membranaceus Inhibits Lipid Oxidation in Fish Feed and Enhances Growth Performance and Antioxidant Capacity in Jian Carp (Cyprinus carpio var. Jian)","authors":"Jing Xu, Gangfu Chen, Min Wu, Qihui Yang, Hua-Tao Li","doi":"10.3390/fishes8120594","DOIUrl":"https://doi.org/10.3390/fishes8120594","url":null,"abstract":"In this study, a linoleic and linolenic acid were incubated with petroleum ether extract, ethyl acetate extract, acetone extract (AE) and aqueous extract of Astragalus membranaceus. The phenolic content and total antioxidant capacity (T-AOC) were determined in the extracts of Astragalus membranaceus (EAms) above. Results showed that EAms decreased the levels of malonaldehyde, conjugated diene, and peroxide value levels in material above. Of all of EAms, AE showed the strongest T-AOC and inhibitory effect on the lipid oxidation. Next, fish feeds were incubated with graded levels of AE. The results showed that AE inhibited lipid oxidation in fish feed. The appropriate dosage for reducing lipid oxidation was 6.74 g AE kg−1 feeds. The effect of EAms on the lipid oxidation may be closely associated with their phenolic content. Then, juvenile Jian carp (Cyprinus carpio var. Jian, 10.2 ± 0.3 g) were fed with diets containing graded levels of AE (0.0, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, and 7.0 g kg−1) for 60 days. Current data displayed that dietary AE increased the growth performance of fish. The optimum dosage for growth promotion was 5.15 g AE kg−1 diet. This result of AE may be ascribed to its enhancing effect on the activity of digestive and absorptive enzymes and antioxidant capacity in digestive organs of fish. Our present study indicated that EAm holds promise as a natural antioxidant for fish and their feed.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":" 22","pages":""},"PeriodicalIF":2.3,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138620659","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}
Neptunea cumingii is an economically important marine shellfish found in the Yellow and Bohai Seas areas of China. In this study, samples of Neptunea cumingii were collected in Zhangzidao and Yantai during spring, summer, autumn, and winter to clarify the gene expression patterns and regulatory mechanisms in their gills in different seasons. Transcriptome analysis was conducted using Neptunea cumingii gill tissues, and genes with significantly different expression levels were extracted for functional verification. The most genes with differences in expression (DEGs) were found in comparisons of the winter and summer samples. Gene enrichment analysis based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes terms showed that these DEGs were mainly involved in immune and metabolic pathways, and they had significant effects on oxidative stress, body metabolism, and protein synthesis in Neptunea cumingii. Further screening of DEGs identified thirty-four genes related to temperature regulation, comprising thirteen genes with roles in innate immunity in shellfish, twelve genes related to oxidative stress, and nine genes related to protein synthesis and energy metabolism. Eleven DEGs were randomly selected for qPCR verification, and the results were consistent with the transcriptome analysis results. In summary, the transcriptome results differed significantly between seasons in the gill tissues of Neptunea cumingii. The expression levels of immune regulatory genes could be promoted in Neptunea cumingii during the high temperature season, whereas the expression of these genes may be inhibited in the low temperature season. The results obtained in this study provide insights into the molecular defense mechanisms that might allow Neptunea cumingii to adapt to climate change.
海螺是一种重要的经济海洋贝类,产于中国黄渤海海域。本研究分别于春、夏、秋、冬采集漳子岛和烟台的三角帆鱼样本,研究不同季节三角帆鱼鳃基因表达模式及调控机制。利用三角帆鱼鳃组织进行转录组分析,提取表达水平差异显著的基因进行功能验证。在冬季和夏季样品的比较中发现了最多的表达差异基因(DEGs)。基于Gene Ontology和Kyoto Encyclopedia of Genes and Genomes术语的基因富集分析表明,这些deg主要参与免疫和代谢途径,对cumingii的氧化应激、机体代谢和蛋白质合成有显著影响。进一步筛选的deg鉴定出34个与温度调节相关的基因,其中13个基因与贝类先天免疫有关,12个基因与氧化应激有关,9个基因与蛋白质合成和能量代谢有关。随机选取11个deg进行qPCR验证,结果与转录组分析结果一致。综上所述,在不同季节,三角帆鱼鳃组织的转录组结果有显著差异。免疫调节基因在高温季节的表达水平可以提高,而在低温季节的表达水平可能会受到抑制。本研究获得的结果为海王星cumingii适应气候变化的分子防御机制提供了见解。
{"title":"Transcriptome Analysis of Gill Tissues from Neptunea cumingii in Different Seasons","authors":"Yifan Zhang, Dandan Zhang, Ying Tian, Junxia Mao, Yang Liu, Zhenlin Hao","doi":"10.3390/fishes8110549","DOIUrl":"https://doi.org/10.3390/fishes8110549","url":null,"abstract":"Neptunea cumingii is an economically important marine shellfish found in the Yellow and Bohai Seas areas of China. In this study, samples of Neptunea cumingii were collected in Zhangzidao and Yantai during spring, summer, autumn, and winter to clarify the gene expression patterns and regulatory mechanisms in their gills in different seasons. Transcriptome analysis was conducted using Neptunea cumingii gill tissues, and genes with significantly different expression levels were extracted for functional verification. The most genes with differences in expression (DEGs) were found in comparisons of the winter and summer samples. Gene enrichment analysis based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes terms showed that these DEGs were mainly involved in immune and metabolic pathways, and they had significant effects on oxidative stress, body metabolism, and protein synthesis in Neptunea cumingii. Further screening of DEGs identified thirty-four genes related to temperature regulation, comprising thirteen genes with roles in innate immunity in shellfish, twelve genes related to oxidative stress, and nine genes related to protein synthesis and energy metabolism. Eleven DEGs were randomly selected for qPCR verification, and the results were consistent with the transcriptome analysis results. In summary, the transcriptome results differed significantly between seasons in the gill tissues of Neptunea cumingii. The expression levels of immune regulatory genes could be promoted in Neptunea cumingii during the high temperature season, whereas the expression of these genes may be inhibited in the low temperature season. The results obtained in this study provide insights into the molecular defense mechanisms that might allow Neptunea cumingii to adapt to climate change.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":"37 23","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135086592","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}
Mark L. Wildhaber, Benjamin M. West, Karlie K. Ditter, Adrian P. Moore, Alex S. Peterson
Grass carp (Ctenopharyngodon idella) are globally important in aquaculture and aquatic vegetation control. However, escaped grass carp have established invasive populations. A targeted keyword search was performed on a carp (order: Cypriniformes) literature database maintained by the U.S. Geological Survey to identify literature relevant to grass carp. Additional sources cited in reviewed documents and provided by numerous reviewers were also included. There were three focus areas designed to provide support for invasive grass carp management: (1) diet and behavior; (2) physiological constraints, toxicity, and biology; and (3) gut physiology. Each focus area provides information to guide development of potential pathways for invasive grass carp control. Information from other carp species was used to fill in gaps where grass carp information was lacking and provide additional, potential research directions. Diet-related information included food selection and aquacultural diet formulations. Behavioral information included stimuli and non-physical barriers to attract, repel, or stop movement. Physiological constraints, toxicology, reproductive control, and biological control provide a research review for control options. Gut physiology and related control pathways provide knowledge to improve toxin or pathogen delivery. This review provides a basis for developing approaches and research for controlling invasive grass carp populations, aquaculture, and native population management.
{"title":"A Review of Grass Carp and Related Species Literature on Diet, Behavior, Toxicology, and Physiology Focused on Informing Development of Controls for Invasive Grass Carp Populations in North America","authors":"Mark L. Wildhaber, Benjamin M. West, Karlie K. Ditter, Adrian P. Moore, Alex S. Peterson","doi":"10.3390/fishes8110547","DOIUrl":"https://doi.org/10.3390/fishes8110547","url":null,"abstract":"Grass carp (Ctenopharyngodon idella) are globally important in aquaculture and aquatic vegetation control. However, escaped grass carp have established invasive populations. A targeted keyword search was performed on a carp (order: Cypriniformes) literature database maintained by the U.S. Geological Survey to identify literature relevant to grass carp. Additional sources cited in reviewed documents and provided by numerous reviewers were also included. There were three focus areas designed to provide support for invasive grass carp management: (1) diet and behavior; (2) physiological constraints, toxicity, and biology; and (3) gut physiology. Each focus area provides information to guide development of potential pathways for invasive grass carp control. Information from other carp species was used to fill in gaps where grass carp information was lacking and provide additional, potential research directions. Diet-related information included food selection and aquacultural diet formulations. Behavioral information included stimuli and non-physical barriers to attract, repel, or stop movement. Physiological constraints, toxicology, reproductive control, and biological control provide a research review for control options. Gut physiology and related control pathways provide knowledge to improve toxin or pathogen delivery. This review provides a basis for developing approaches and research for controlling invasive grass carp populations, aquaculture, and native population management.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":" April","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135186818","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}
H.G. Moser was not particularly well known regarding the Elopomorpha, but he began his seminal 1981 fish larvae morphology review by describing the mysteries of European eels and their leptocephali, and he eventually described some California Current leptocephali. Descriptions of all types of leptocephali and then microscope photographs have revealed complex pigmentation patterns and diverse body shapes that parallel the features of the other teleost fish larvae that his review showed so clearly, some of which appear to mimic gelatinous zooplankton (GZ). Most recently, underwater photographs and video of leptocephali indicate that predator avoidance through transparency, shape-change-mediated mimicry, or morphological features have evolved in response to natural selection from predation in ways generally similar to other fish larvae. Several families of leptocephali perform remarkable curling into round or flattened shapes or use expandable chromatophores when threatened, which appears to mimic GZ for predation reduction. Like a number of other teleost fish larvae, some leptocephali have body extensions or telescopic eyes, and at least one has a long caudal filament with pigmented swellings that is similar to the remarkable GZ mimicry appendages of some fish larvae. The morphology and use of mimicry of leptocephali in comparison to other fish larvae is reviewed as a tribute to H.G. Moser’s remarkable career.
{"title":"43 Years after H.G. Moser’s Seminal “Morphological and Functional Aspects of Marine Fish Larvae”: The Commonalities of Leptocephali and Larvae of Other Marine Teleosts","authors":"Michael J. Miller","doi":"10.3390/fishes8110548","DOIUrl":"https://doi.org/10.3390/fishes8110548","url":null,"abstract":"H.G. Moser was not particularly well known regarding the Elopomorpha, but he began his seminal 1981 fish larvae morphology review by describing the mysteries of European eels and their leptocephali, and he eventually described some California Current leptocephali. Descriptions of all types of leptocephali and then microscope photographs have revealed complex pigmentation patterns and diverse body shapes that parallel the features of the other teleost fish larvae that his review showed so clearly, some of which appear to mimic gelatinous zooplankton (GZ). Most recently, underwater photographs and video of leptocephali indicate that predator avoidance through transparency, shape-change-mediated mimicry, or morphological features have evolved in response to natural selection from predation in ways generally similar to other fish larvae. Several families of leptocephali perform remarkable curling into round or flattened shapes or use expandable chromatophores when threatened, which appears to mimic GZ for predation reduction. Like a number of other teleost fish larvae, some leptocephali have body extensions or telescopic eyes, and at least one has a long caudal filament with pigmented swellings that is similar to the remarkable GZ mimicry appendages of some fish larvae. The morphology and use of mimicry of leptocephali in comparison to other fish larvae is reviewed as a tribute to H.G. Moser’s remarkable career.","PeriodicalId":12405,"journal":{"name":"Fishes","volume":" December","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135186680","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}