Aquaculture of red swamp crayfish Procambarus clarkii is an emerging farming industry in China.As shown recently,one of the most significant diseases affecting the red swamp crayfish is caused by overabundance of epib...Aquaculture of red swamp crayfish Procambarus clarkii is an emerging farming industry in China.As shown recently,one of the most significant diseases affecting the red swamp crayfish is caused by overabundance of epibiotic peritrichs,a group of ciliated protists that are commonly found living as epibionts on aquatic animals.Nevertheless,few studies focusing on this issue have been performed.As part of a faunal study carried out in the Lake Weishan Wetland,China,four colonial sessilid peritrichs,namely Epicarchesium granulatum,Epistylis bimarginata,Epistylis semiciculus,and Zoothamnium procerius,attached to P.clarkii are documented.For each species,redescriptions and improved diagnoses are supplied.As a further aid to identification,14 new rDNA sequences of these four and a closely related species were obtained.In addition,as an aid for future studies on epibiotic ciliates,we supply a list and information about recent integrative studies that document the geographic distributions of related taxa.展开更多
Genetic breeding is an important approach to improve the economic traits of aquaculture animals.Unfortunately,the genetic basis for important economic traits of red swamp crayfish,including growth-related traits,has n...Genetic breeding is an important approach to improve the economic traits of aquaculture animals.Unfortunately,the genetic basis for important economic traits of red swamp crayfish,including growth-related traits,has not yet been reported.In the present study,two full-sib families and two natural populations were employed to identify quantitative trait loci(QTLs)for growth-related traits of red swamp crayfish.In total,28 QTLs for five growth-related traits,including body weight,body length,carapace length,carapace width,and abdomen length,were repeatedly identified in more than two families/populations,by means of association analysis;nine of these displayed a heterosis effect.The phenotypic variations of the five investigated traits explained by the 28 QTLs ranged from 4.2%to 19.0%.Eight additive and three heterosis QTLs were further successfully validated using comparative analysis of favoured alleles between the small and big size crayfish groups in the natural population.In conclusion,this study investigated the genetic basis of growth-related traits in red swamp crayfish,which is of great significance for their application in the future molecular breeding of the species.展开更多
Invasive species and habitat degradation are the main reasons for freshwater biodiversity loss. Reports on the habitat degradation and invasion ecology of Red Swamp crayfish(Procambarus clarkii) are few, although it i...Invasive species and habitat degradation are the main reasons for freshwater biodiversity loss. Reports on the habitat degradation and invasion ecology of Red Swamp crayfish(Procambarus clarkii) are few, although it is one of the most devastating invasive species in freshwater ecosystems. Based on a three-year investigation during 2017-2019 in West Dongting Lake, this study used Principal Component Analysis(PCA), Generalized Linear Model(GLM) and Bayesian model to analyze the relationships of P. clarkii stocks and environment factors in natural and modified wetlands. The results showed that the abundance of P. clarkii was positively correlated with total nitrogen, total phosphorus, water temperature, pH, water depth, and water transparency;while it was negatively correlated with dissolved oxygen and redox potential. The difference between P. clarkii stocks in natural and modified wetlands was nonsignificant. The P. clarkii stock decreased yearly, as levels in both 2018 and 2019 were significantly lower than in 2017. We concluded that inter-annual variation of the hydrological regime plays an important role in P. clarkii dynamics, and thus it is of great importance to ensure that the water level and flow velocity in summer to control the invasive P. clarkii.展开更多
基金supported by the Laoshan Laboratory(Project No.LSKJ202203201)the National Natural Science Foundation of China(Project No.32000300,32030015)+2 种基金the Natural Science Foundation of Shandong Province(Project No.ZR2022QC096)China Postdoctoral Science Foundation Grant(Project No.2022M711922)the Researchers Supporting Project(Project No.RSP 2025R7)King Saud University,Riyadh,Saudi Arabia.
文摘Aquaculture of red swamp crayfish Procambarus clarkii is an emerging farming industry in China.As shown recently,one of the most significant diseases affecting the red swamp crayfish is caused by overabundance of epibiotic peritrichs,a group of ciliated protists that are commonly found living as epibionts on aquatic animals.Nevertheless,few studies focusing on this issue have been performed.As part of a faunal study carried out in the Lake Weishan Wetland,China,four colonial sessilid peritrichs,namely Epicarchesium granulatum,Epistylis bimarginata,Epistylis semiciculus,and Zoothamnium procerius,attached to P.clarkii are documented.For each species,redescriptions and improved diagnoses are supplied.As a further aid to identification,14 new rDNA sequences of these four and a closely related species were obtained.In addition,as an aid for future studies on epibiotic ciliates,we supply a list and information about recent integrative studies that document the geographic distributions of related taxa.
基金the key research and development program of Hubei province(2021BBA232)the earmarked fund for CARS-48,and the research start-up fund of high level talent introduction of Huazhong Agricultural University.
文摘Genetic breeding is an important approach to improve the economic traits of aquaculture animals.Unfortunately,the genetic basis for important economic traits of red swamp crayfish,including growth-related traits,has not yet been reported.In the present study,two full-sib families and two natural populations were employed to identify quantitative trait loci(QTLs)for growth-related traits of red swamp crayfish.In total,28 QTLs for five growth-related traits,including body weight,body length,carapace length,carapace width,and abdomen length,were repeatedly identified in more than two families/populations,by means of association analysis;nine of these displayed a heterosis effect.The phenotypic variations of the five investigated traits explained by the 28 QTLs ranged from 4.2%to 19.0%.Eight additive and three heterosis QTLs were further successfully validated using comparative analysis of favoured alleles between the small and big size crayfish groups in the natural population.In conclusion,this study investigated the genetic basis of growth-related traits in red swamp crayfish,which is of great significance for their application in the future molecular breeding of the species.
基金The Fundamental Research Funds for the Central Universities (2017ZY15)The National Key Research and Development Program of China (2017YFC0405303)。
文摘Invasive species and habitat degradation are the main reasons for freshwater biodiversity loss. Reports on the habitat degradation and invasion ecology of Red Swamp crayfish(Procambarus clarkii) are few, although it is one of the most devastating invasive species in freshwater ecosystems. Based on a three-year investigation during 2017-2019 in West Dongting Lake, this study used Principal Component Analysis(PCA), Generalized Linear Model(GLM) and Bayesian model to analyze the relationships of P. clarkii stocks and environment factors in natural and modified wetlands. The results showed that the abundance of P. clarkii was positively correlated with total nitrogen, total phosphorus, water temperature, pH, water depth, and water transparency;while it was negatively correlated with dissolved oxygen and redox potential. The difference between P. clarkii stocks in natural and modified wetlands was nonsignificant. The P. clarkii stock decreased yearly, as levels in both 2018 and 2019 were significantly lower than in 2017. We concluded that inter-annual variation of the hydrological regime plays an important role in P. clarkii dynamics, and thus it is of great importance to ensure that the water level and flow velocity in summer to control the invasive P. clarkii.
