Salmonids like whitefish(Coregonus spp.)are often propagated in supportive breeding.Spawners are caught from their spawning locations,their gametes mixed,and the resulting offspring reared in a protected environment b...Salmonids like whitefish(Coregonus spp.)are often propagated in supportive breeding.Spawners are caught from their spawning locations,their gametes mixed,and the resulting offspring reared in a protected environment before being released into the wild.This procedure can affect sexual selection,for example,by enhancing the importance of sperm competition or by reducing the relevance of sexual signals.While it is often unclear how sperm competitiveness is affected by a male's overall genetic quality,there is accumulating evidence that sexual signals reveal good genes and that mate choice based on such signals can increase offspring viability(Auld et al.2019).Therefore,supportive breeding may affect the genetic variance and the mean genetic quality of next generations.展开更多
The qualitative and quantitative composition of primordial germ cells(PGCs)and the genetic variability of embryos of the Coregonus nasus from the Ob river basin and domesticated population breeding outside the natural...The qualitative and quantitative composition of primordial germ cells(PGCs)and the genetic variability of embryos of the Coregonus nasus from the Ob river basin and domesticated population breeding outside the natural areal was examined.In the broad whitefish,typical,binuclear,polymorphic nuclei cells,as well as PGCs represented primary gonocytes during embryogenesis in clusters.When hatching larvae PGCs mitoses were noted only in domesticated juveniles.The genetic variability of embryos of the broad whitefish was studied by polymerase chain reaction of inter simple sequence repeats(ISSR-PCR).The high polymorphism of the broad whitefish cultured population was revealed.The proportion of polymorphic bands was 89.4%,Nei’s genetic diversity was 0.32.Reproduction of the domesticated broad whitefish did not affect the overall level of polymorphism of neutral DNA markers.These findings suggest the preservation of cytomorphological and genetic diversity in C.nasus embryo from different sources.展开更多
We report here arsenic speciation in 1643 freshwater fish samples,representing 14 common fish species from 53 waterbodies in Alberta,Canada.Arsenic species were extracted from fish muscle tissue.Arsenic species in the...We report here arsenic speciation in 1643 freshwater fish samples,representing 14 common fish species from 53 waterbodies in Alberta,Canada.Arsenic species were extracted from fish muscle tissue.Arsenic species in the extracts were separated using anion-exchange high-performance liquid chromatography(HPLC)and quantified using inductively coupled plasma mass spectrometry(ICPMS).The total arsenic concentrations in fish ranged from 2.8 to 1200μg/kg(in wet weight of sample)(mean 71±101μg/kg),which are all below the 2000μg/kg(wet weight)maximum allowable total arsenic in fish,recommended by the Ontario Ministry of the Environment.In 99.7%,or 1638 of all 1643 freshwater fish samples analyzed,arsenobetaine(AsB)was detectable,with concentrations higher than the method detection limit of 0.25μg/kg(wet weight).Dimethylarsinic acid(DMA)was detectable(concentration>0.25μg/kg)in 92.1%,or 1514 of the 1643 freshwater fish samples.Inorganic arsenate(iAs^(Ⅴ))was detectable(>0.25μg/kg)in 1119 fish(i.e.,68.1% of 1643 samples).Monomethylarsonic acid(MMA)was detectable(>0.25μg/kg)in 418 fish(25.4%of 1643 samples).The concentrations of arsenic species in the 1643 fish samples varied by as much as three orders of magnitude,ranging from below the method detection limit of 0.25μg/kg to the maximum concentrations of 380μg/kg for AsB,150μg/kg for DMA,70μg/kg for iAs^(Ⅴ),and 51μg/kg for MMA.AsB made up 46.1%±26.2% of total arsenic species.Arsenic speciation patterns varied between lake whitefish,northern pike,and walleye,the three most common types of fish analyzed.The relative proportion of DMA in northern pike was larger than in lake whitefish and walleye,and conversely,the relative proportion of iAs^(Ⅴ) was lower in northern pike.Seven unknown arsenic species were detected,and their chromatographic retention time did not match with those of available arsenic standards.At least one unknown arsenic species was detected in 33.4%,or 549 of 1643 freshwater fish samples.The concentrations of unknown arsenic species were as high as 61μg/kg.Future research is necessary to identify unknown arsenic species and to determine contributing factors to the observed arsenic species patterns and concentrations.展开更多
基金This work was supported by the Swiss National Science Foundation[31003A.182265].
文摘Salmonids like whitefish(Coregonus spp.)are often propagated in supportive breeding.Spawners are caught from their spawning locations,their gametes mixed,and the resulting offspring reared in a protected environment before being released into the wild.This procedure can affect sexual selection,for example,by enhancing the importance of sperm competition or by reducing the relevance of sexual signals.While it is often unclear how sperm competitiveness is affected by a male's overall genetic quality,there is accumulating evidence that sexual signals reveal good genes and that mate choice based on such signals can increase offspring viability(Auld et al.2019).Therefore,supportive breeding may affect the genetic variance and the mean genetic quality of next generations.
文摘The qualitative and quantitative composition of primordial germ cells(PGCs)and the genetic variability of embryos of the Coregonus nasus from the Ob river basin and domesticated population breeding outside the natural areal was examined.In the broad whitefish,typical,binuclear,polymorphic nuclei cells,as well as PGCs represented primary gonocytes during embryogenesis in clusters.When hatching larvae PGCs mitoses were noted only in domesticated juveniles.The genetic variability of embryos of the broad whitefish was studied by polymerase chain reaction of inter simple sequence repeats(ISSR-PCR).The high polymorphism of the broad whitefish cultured population was revealed.The proportion of polymorphic bands was 89.4%,Nei’s genetic diversity was 0.32.Reproduction of the domesticated broad whitefish did not affect the overall level of polymorphism of neutral DNA markers.These findings suggest the preservation of cytomorphological and genetic diversity in C.nasus embryo from different sources.
基金supported by Alberta Health,Alberta Innovates,the Canada Research Chairs program,the Canadian Institutes of Health Research,and the Natural Sciences and Engineering Research Council of Canada.
文摘We report here arsenic speciation in 1643 freshwater fish samples,representing 14 common fish species from 53 waterbodies in Alberta,Canada.Arsenic species were extracted from fish muscle tissue.Arsenic species in the extracts were separated using anion-exchange high-performance liquid chromatography(HPLC)and quantified using inductively coupled plasma mass spectrometry(ICPMS).The total arsenic concentrations in fish ranged from 2.8 to 1200μg/kg(in wet weight of sample)(mean 71±101μg/kg),which are all below the 2000μg/kg(wet weight)maximum allowable total arsenic in fish,recommended by the Ontario Ministry of the Environment.In 99.7%,or 1638 of all 1643 freshwater fish samples analyzed,arsenobetaine(AsB)was detectable,with concentrations higher than the method detection limit of 0.25μg/kg(wet weight).Dimethylarsinic acid(DMA)was detectable(concentration>0.25μg/kg)in 92.1%,or 1514 of the 1643 freshwater fish samples.Inorganic arsenate(iAs^(Ⅴ))was detectable(>0.25μg/kg)in 1119 fish(i.e.,68.1% of 1643 samples).Monomethylarsonic acid(MMA)was detectable(>0.25μg/kg)in 418 fish(25.4%of 1643 samples).The concentrations of arsenic species in the 1643 fish samples varied by as much as three orders of magnitude,ranging from below the method detection limit of 0.25μg/kg to the maximum concentrations of 380μg/kg for AsB,150μg/kg for DMA,70μg/kg for iAs^(Ⅴ),and 51μg/kg for MMA.AsB made up 46.1%±26.2% of total arsenic species.Arsenic speciation patterns varied between lake whitefish,northern pike,and walleye,the three most common types of fish analyzed.The relative proportion of DMA in northern pike was larger than in lake whitefish and walleye,and conversely,the relative proportion of iAs^(Ⅴ) was lower in northern pike.Seven unknown arsenic species were detected,and their chromatographic retention time did not match with those of available arsenic standards.At least one unknown arsenic species was detected in 33.4%,or 549 of 1643 freshwater fish samples.The concentrations of unknown arsenic species were as high as 61μg/kg.Future research is necessary to identify unknown arsenic species and to determine contributing factors to the observed arsenic species patterns and concentrations.
