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Changes in the adult sex ratio of six duck species breeding populations over two decades
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作者 Monika Homolkova Petr Musil +4 位作者 Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova Jan Zouhar 《Avian Research》 SCIE CSCD 2024年第2期202-210,共9页
Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of research... Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered species.Species with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction risk.In this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and 2022.This evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in winter.We determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and males.In the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early 2020s.However,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population. 展开更多
关键词 Adult sex ratio breeding population population dynamics Red-listed species WATERFOWL Winter weather conditions
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Long-term trends in the abundance and breeding performance in Adélie penguins:the Argentine Ecosystem Monitoring Program
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作者 Mariana A.JUÁRES AnahíM.SILVESTRO +1 位作者 Brenda C.ALFONSO M.Mercedes SANTOS 《Advances in Polar Science》 CSCD 2024年第1期132-140,共9页
In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Poin... In this work,we report long-term trends in the abundance and breeding performance of Adélie penguins(Pygoscelis adeliae)nesting in three Antarctic colonies(i.e.,at Martin Point,South Orkneys Islands;Stranger Point/Cabo Funes,South Shetland Islands;and Esperanza/Hope Bay in the Antarctic Peninsula)from 1995/96 to 2022/23.Using yearly count data of breeding groups selected,we observed a decline in the number of breeding pairs and chicks in crèche at all colonies studied.However,the magnitude of change was higher at Stranger Point than that in the remaining colonies.Moreover,the index of breeding success,which was calculated as the ratio of chicks in crèche to breeding pairs,exhibited no apparent trend throughout the study period.However,it displayed greater variability at Martin Point compared to the other two colonies under investigation.Although the number of chicks in crèche of Adélie penguins showed a declining pattern,the average breeding performance was similar to that reported in gentoo penguin colonies,specifically,those undergoing a population increase(even in sympatric colonies facing similar local conditions).Consequently,it is plausible to assume a reduction of the over-winter survival as a likely cause of the declining trend observed,at least in the Stranger Point and Esperanza colonies.However,we cannot rule out local effects during the breeding season affecting the Adélie population of Martin Point. 展开更多
关键词 long-term monitoring Adélie penguin breeding pairs chicks crèched breeding success population trends
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Future livestock breeding: Precision breeding based on multiomics information and population personalization 被引量:4
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作者 YANG Ya-lan ZHOU Rong LI Kui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第12期2784-2791,共8页
With the rapid development of molecular biology and related disciplines, animal breeding has moved from conventional breeding to molecular breeding. Marker-assisted selection and genomic selection have become mainstre... With the rapid development of molecular biology and related disciplines, animal breeding has moved from conventional breeding to molecular breeding. Marker-assisted selection and genomic selection have become mainstream practices in molecular breeding of livestock. However, these techniques only use information from genomic variation but not multi-omics information, thus do not fully explain the molecular basis of phenotypic variations in complex traits. In addition, the accuracy of breeding value estimation based on these techniques is occasionally controversial in different populations or varieties. Given the rapid development of high-throughput sequencing techniques and functional genome and dramatic reductions in the overall cost of sequencing, it is possible to clarify the interactions between genes and formation of phenotypes using massive sets of omic-level data from studies of the transcriptome, proteome, epigenome, and metabolome. During livestock breeding, multi-omics information regarding breeding populations and individuals should be taken into account. The interactive regulatory networks governing gene regulation and phenotype formation in diverse livestock population, varieties and species should be analyzed. In addition, a multi-omics regulatory breeding model should be constructed. Precision, population-personalized breeding is expected to become a crucial practice in future livestock breeding. Precision breeding of individuals can be achieved by combining population genomic information at multi-omics levels together with genomic selection and genome editing techniques. 展开更多
关键词 livestock breeding multi-omics population personalization
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Effects of breeding success,age and sex on breeding dispersal of a reintroduced population of the Crested Ibis(Nipponia nippon)in Ningshan County,China 被引量:4
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作者 Rong Dong Xinping Ye +4 位作者 Lin Zhong Xia Li Min Li Huaqiang Wang Xiaoping Yu 《Avian Research》 CSCD 2018年第4期314-320,共7页
Background: Breeding dispersal is an important ecological process that affects species' population dynamics and colonization of new suitable areas. Knowledge of the causes and consequences of breeding dispersal is... Background: Breeding dispersal is an important ecological process that affects species' population dynamics and colonization of new suitable areas. Knowledge of the causes and consequences of breeding dispersal is fundamental to our understanding of avian ecology and evolution. Although breeding success for a wild and reintroduced population of the Crested Ibis(Nipponia nippon) has been reported, the relationships between individuals' breeding dispersal and their breeding success, age and sex remain unclear.Methods: Ibises' breeding dispersal distance, which is the distance moved by adults between sites of reproduction, was estimated based on the observations of consecutive breeding sites of marked ibis individuals. From observational and capture-recapture data(n as = 102) over 9 years, individuals' breeding dispersal probability in relation to age, sex, and reproductive success wanalyzed via a generalized linear mixed effect modeling approach.Results: Our results show that 55% males and 51% females keep their previous territories following nesting success. Failed breeding attempts increased dispersal probabilities. Both females and males failed in breeding were more likely to disperse with greater distances than successful birds(females: 825 ± 216 m vs 196 ± 101 m, males: 372 Crested Ibis exhibited a female-biased dispersal pattern that the mean dispersal distance± 164 m vs 210 ± 127 m). of females(435 ± 234 m) was much larger than that of males(294 ± 172 m).Conclusion: Our results are fundamental to predict the patterns of breeding dispersal related to reproductive success under different release sites. From the conservation point of view, landscape connectivity between the reintroduced populations should be taken into account in accordance with the distance of breeding dispersal. 展开更多
关键词 breeding dispersal breeding SUCCESS Generalized linear mixed effect model Crested IBIS Reintroduced population
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Structure of Allozymatic Diversity of Ten Temperate and Adapted Exotic Breeding Populations of Maize (Zea mays L.)
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作者 ZHENG Da-hao YU Yang +1 位作者 WANG Zhen-ping LI Yan-ru 《Agricultural Sciences in China》 CAS CSCD 2009年第8期920-930,共11页
Ten temperate and adapted exotic breeding populations of maize were studied with electrophoretic techniques. Three isozyme systems coded by nine allozyme loci were used for evaluating the genetic variability within an... Ten temperate and adapted exotic breeding populations of maize were studied with electrophoretic techniques. Three isozyme systems coded by nine allozyme loci were used for evaluating the genetic variability within and among populations. The results revealed that 78.57% of allozyme loci were polymorphic. Low allelic variation with a mean number of 1.84 alleles per locus per population was detected. But, these populations still maintained higher level of heterozygosity; moreover, the exotic populations had greater gene diversity than the temperate populations. All the populations were non-panmictic with negative Wright's fixation indexes (-0.091— -0.424). The tropical BS 16 was typified by maximum allelic richness, percent of polymorphic loci and heterozygosity. More than 93% of the gene diversity maintained within populations, and the genetic differentiation among populations was low (0.002—0.191). Multivariate analysis demonstrated that the tropical BS29 diverged from other populations in the reverse direction. The temperate BS9 and tropical BS16 were divergent each other, and highly differentiated from other temperate and tropical populations, consequently, these two populations would be analogically postulated as potential germplasms to establish new heterotic groups for temperate maize breeding programs. 展开更多
关键词 MAIZE breeding population ALLOZYME diversity structure multivariate analysis
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Analysis of genetic diversity and population structure of Chinese yak breeds (Bos grunniens) using microsatellite markers 被引量:8
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作者 Guixiang Zhang Weisheng Chen +5 位作者 Ming Xue Zhigang Wang Hong Chang Xu Han Xinjun Liao Donglei Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第4期233-238,共6页
Nine Chinese yak breeds (Maiwa, Tianzhu White, Qinghai Plateau, Sibu, Zhongdian, Pali, Tibetan High Mountain, Jiulong, and Xinjiang) and Gayal were analyzed by means of 16 microsatellite markers to determine the lev... Nine Chinese yak breeds (Maiwa, Tianzhu White, Qinghai Plateau, Sibu, Zhongdian, Pali, Tibetan High Mountain, Jiulong, and Xinjiang) and Gayal were analyzed by means of 16 microsatellite markers to determine the level of genetic variation within populations, genetic relationship between populations, and population structure for each breed. A total of 206 microsatellite alleles were observed. Mean F-statistics (0.056) for 9 yak breeds indicated that 94.4% of the genetic variation was observed within yak breeds and 5.6% of the genetic variation existed amongst breeds. The Neighbor-Joining phylogenetic tree was constructed based on Nei's standard genetic distances and two clusters were obtained. The Gayal separated from the yaks far away and formed one cluster and 9 yak breeds were grouped together. The analysis of population structure for 9 yak breeds and the Gayal showed that they resulted in four clusters; one cluster includes yaks from Tibet Autonomous Region and Qinghai Province, one cluster combines Zhongdian, Maiwa, and Tianzhu White, and Jiulong and Xinjiang come into the third cluster. Pali was mainly in the first cluster (90%), Jiulong was mainly in the second cluster (87.1%), Zhongdian was primarily in the third cluster (83%), and the other yak breeds were distributed in two to three clusters. The Gayal was positively left in the fourth cluster (99.3%). 展开更多
关键词 Chinese yak breeds MICROSATELLITE genetic diversity population structure
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Genome-Wide Association Study for Milled Grain Appearance Traits Using Multi-Parent Advanced Generation Intercross Population in Rice
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作者 LI Xiaoxiang LIU Jindong +10 位作者 GUO Liang WEI Xiucai WANG Yamei PAN Xiaowu DONG Zheng LIU Wenqiang LIU Licheng MIN Jun LIU Sanxiong YE Guoyou LI Yongchao 《Rice science》 SCIE CSCD 2023年第5期364-368,I0007-I0012,共11页
The identification of loci and markers associated with milled grain appearance traits is essential for breeding high-yielding and good-quality rice variety.To detect stable loci for these characteristics,grain length(... The identification of loci and markers associated with milled grain appearance traits is essential for breeding high-yielding and good-quality rice variety.To detect stable loci for these characteristics,grain length(GL),grain width(GW),grain length/width(GLW),chalkiness degree(CD),chalky-grain rate(CR)and translucency degree(TD)of 378 rice lines were evaluated in three seasons.These lines were derived from a multi-parent advanced generation intercross(MAGIC)population. 展开更多
关键词 breeding YIELDING population
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Population genomics reveals demographic history and selection signatures of hazelnut (Corylus)
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作者 Zhen Yang Wenxu Ma +5 位作者 Lujun Wang Xiaohong Yang Tiantian Zhao Lisong Liang Guixi Wang Qinghua Ma 《Horticulture Research》 SCIE CSCD 2023年第5期247-259,共13页
Hazelnut(Corylus spp.)is known as one of the four famous tree nuts in the world due to its pleasant taste and nutritional benefits.However,hazelnut promotion worldwide is increasingly challenged by global climate chan... Hazelnut(Corylus spp.)is known as one of the four famous tree nuts in the world due to its pleasant taste and nutritional benefits.However,hazelnut promotion worldwide is increasingly challenged by global climate change,limiting its production to a few regions.Focusing on the eurytopic Section Phyllochlamys,we conducted whole-genome resequencing of 125 diverse accessions from five geo-ecological zones in Eurasia to elucidate the genomic basis of adaptation and improvement.Population structure inference outlined five distinct genetic lineages corresponding to climate conditions and breeding background,and highlighted the differentiation between European and Asian lineages.Demographic dynamics and ecological niche modeling revealed that Pleistocene climatic oscillations dominantly shaped the extant genetic patterns,and multiple environmental factors have contributed to the lineage divergence.Whole-genome scans identified 279,111,and 164 selective sweeps that underlie local adaptation in Corylus heterophylla,Corylus kweichowensis,and Corylus yunnanensis,respectively.Relevant positively selected genes were mainly involved in regulating signaling pathways,growth and development,and stress resistance.The improvement signatures of hybrid hazelnut were concentrated in 312 and 316 selected genes,when compared to C.heterophylla and Corylus avellana,respectively,including those that regulate protein polymerization,photosynthesis,and response to water deprivation.Among these loci,22 candidate genes were highly associated with the regulation of biological quality.Our study provides insights into evolutionary processes and the molecular basis of how sibling species adapt to contrasting environments,and offers valuable resources for future climate-resilient breeding. 展开更多
关键词 breeding population SIGNATURE
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Genetic diversity and elite gene introgression reveal the japonica rice breeding in northern China 被引量:6
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作者 LIU Dan WANG Jia-yu +3 位作者 WANG Xiao-xue YANG Xian-li SUN Jian CHEN Wen-fu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第5期811-822,共12页
Abundant genetic diversity and rational population structure of germplasm benefit crop breeding greatly.To investigate genetic variation among geographically diverse set of japonica germplasm,we analyzed 233 japonica ... Abundant genetic diversity and rational population structure of germplasm benefit crop breeding greatly.To investigate genetic variation among geographically diverse set of japonica germplasm,we analyzed 233 japonica rice cultivars collected from Liaoning,Jilin and Heilongjiang provinces of China,which were released from 1970 to 2011 by using 62 simple sequence repeat(SSR) markers and 8 functional gene tags related to yield.A total of 195 alleles(N_a) were detected with an average of 3.61 per locus,indicating a low level of genetic diversity level among all individuals.The genetic diversity of the cultivars from Jilin Province was the highest among the three geographic distribution zones.Moreover,the genetic diversity was increased slightly with the released period of cultivars from 1970 to 2011.The analysis of molecular variance(AMOVA) revealed that genetic differentiation was more diverse within the populations than that among the populations.The neighbor-joining(NJ) tree indicated that cultivar clusters based on geographic distribution represented three independent groups,among which the cluster of cultivars from Heilongjiang is distinctly different to the cluster of cultivars from Liaoning.For the examined functional genes,two or three allelic variations for each were detected,except for IPA1 and GW2,and most of elite genes had been introgressed in modem japonica rice varieties.These results provide a valuable evaluation for genetic backgrounds of current japonica rice and will be used directly for japonica rice breeding in future. 展开更多
关键词 breeding elite alleles populations Heilongjiang cultivar germplasm Liaoning distinctly panicle
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Migration routes,population status and important sites used by the globally threatened Black-faced Spoonbill(Platalea minor):a synthesis of surveys and tracking studies 被引量:3
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作者 Yiwen Chen Yat-tung Yu +3 位作者 Fanjuan Meng Xueqin Deng Lei Cao Anthony David Fox 《Avian Research》 SCIE CSCD 2021年第4期425-441,共17页
Background:The Black-faced Spoonbill(Platalea minor)is a globally threatened species,nesting mainly in western Korea with smaller numbers breeding in Liaoning Province,China,and Far East Russia.Recent winter field sur... Background:The Black-faced Spoonbill(Platalea minor)is a globally threatened species,nesting mainly in western Korea with smaller numbers breeding in Liaoning Province,China,and Far East Russia.Recent winter field surveys to estimate the species'population size were almost totally conducted in coastal areas,but tracking studies showed that some individuals now winter inland.To ensure its long-term survival,we need a more comprehensive assessment of the current distribution and abundance of the species.Methods:We combined the most recent count data and satellite tracking information to update existing informa-tion about the population abundance and distribution of the Black-faced Spoonbill at all stages of its annual life cycle,and how these have changed during 2004-2020.Results:Black-faced Spoonbills mainly breed on the west coast of the Korean peninsula,while immature birds show a wider summer distribution throughout Yellow Sea coastal areas,when a few remain on wintering sites in the south.Combined tracking results and mid-winter counts confirmed known wintering sites on the east and south coasts of China,but showed that the species also winters on wetlands in the Yangtze River floodplain and in Southeast Asia.During 2004-2020,counts of wintering birds in coastal habitats increased from 1198 to 4864,with numbers wintering on the island of Taiwan contributing most to the overall increase.Latest counts found 5222 in 2021.We also identify key wintering and stopover sites as well as their current conservation status.Conclusions:This study revised the known summering and wintering ranges of the Black-faced Spoonbill and assessed the conservation status of key sites based on a combination of field survey and satellite tracking data.We recommend prioritisation of further field research to identify and survey inland wintering areas in the Yangtze River floodplain and summering areas of immature birds.More tracking of adult individuals and birds during spring migration is necessary to fill these information gaps.We also suggest establishing a Black-faced Spoonbill monitoring platform to store,share and show real-time distribution range and population abundance data. 展开更多
关键词 Black-faced Spoonbill breeding distribution Coastal mudflats Conservation status Platalea minor population abundance Winter distribution Yangtze River floodplain
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Microsatellite analysis of genetic diversity and population structure of freshwater mussel(Lamprotula leai) 被引量:2
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作者 Jin-Jin MIN Rong-Hui YE +1 位作者 Gen-Fang ZHANG Rong-Quan ZHENG 《Zoological Research》 CAS CSCD 2015年第1期34-40,共7页
Lamprotula leai is one of the most commercially important freshwater pearl mussels in China, but there is limited data on its genetic diversity and population structure. In the present study, 119 individuals from four... Lamprotula leai is one of the most commercially important freshwater pearl mussels in China, but there is limited data on its genetic diversity and population structure. In the present study, 119 individuals from four major geographical populations were investigated using 15 microsatellite loci identified via cross-species amplification. A total of 114 alleles were detected, with an average of 7.6 alleles per locus(range: 2 to 21). Among the four stocks, those from Hung-tse Lake and Poyang Lake had the lowest(0.412) and highest(0.455) observed heterozygosity respectively. The polymorphism information content(PIC) ranged from 0.374 to 0.927(mean: 0.907). AMOVA showed that 12.56% and 44.68% genetic variances were among populations and within individuals, respectively. Pairwise Fst ranged from 0.073 to 0.146, indicating medium genetic differentiation among the populations. In aggregate, our results suggest that inbreeding is a crucial factor accounting for deviations from Hardy–Weinberg equilibrium at 12 loci. Moreover, the genetic distance among four stocks ranged from 0.192 to 0.890. Poyang Lake and Hung-tse Lake were clustered together, joined with Dongting Lake and Anqing Lake. Given that specimens from Hungtse Lake showed the highest average allele richness, expected heterozygosity and PIC, this location may be the source of the highest quality germplasm resources and the stock from this area may be the best for future breeding efforts. 展开更多
关键词 alleles populations microsatellite heterozygosity freshwater ranged breeding stocks AMOVA germplasm
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Comparisons of Growth and Survival Performance Among Selected Families and Wild Populations of Fenneropenaeus chinensis
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作者 LUO Kun KONG Jie +3 位作者 MENG Xianhong LUAN Sheng CAO Baoxiang CHEN Baolong 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第2期407-412,共6页
In this study,families of selected population for growth(SP_BWT),selected population for white spot syndrome virus(WSSV)resistance(SP_RW),Bohai wild population(WP_BH)and Huanghai wild population(WP_HH)of F.chinensis w... In this study,families of selected population for growth(SP_BWT),selected population for white spot syndrome virus(WSSV)resistance(SP_RW),Bohai wild population(WP_BH)and Huanghai wild population(WP_HH)of F.chinensis were constructed through artificial insemination and with the standardized procedure of larvae rearing.Growth and survival performance were studied among four populations after a 70 days common test.The results showed that the maximum least square mean of body weight was 17.50 g in SP_BWT while the minimum was 13.03 g in WP_HH.Compared with WP_BH,body weight of SP_BWT increased by 23.41%(P<0.01)and that of SP_RW by 12.20%(P>0.05).Body weights of SP_BWT and SP_RW were significantly higher than that of WP_HH,which increased by 34.31%(P<0.01)and 22.10%(P<0.05),respectively.The mean AGR of four populations was 0.19,0.18,0.17 and 0.16 g d^(-1),respectively.Coefficient of variation of body weight among four populations was high,which ranged from 32.67% to 35.25%.Such a range showed that there was the potentiality for further improvement in selected populations.Coefficient of variation of survival rate among four populations was low,varying between 3.20% and 5.90%.The difference of survival was highly significant(P<0.01)between SP_BWT and WP_BH,and significant(P<0.05)between SP_RW and WP_BH.However,no significant difference among other populations(P>0.05)was observed.Different growth performances were also observed among different families in each population.The body weight of 798F family was the highest.The absolute growth rate(AGR)was 0.25 g d^(-1),150%higher than that of the lowest one,0.1 g d^(-1) in 807F family.Survival rate of families among four populations was different.The highest was 94.74%,and the lowest was 71.88%. 展开更多
关键词 Fenneropenaeus CHINENSIS GROWTH SURVIVAL rate selective breeding genetic gain WILD population
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Abundance and Breeding of the Common Skittering Frog(Euphlyctis cyanophlyctis)and Bull Frog(Hoplobatrachus tigerinus)at Rawal Lake,Islamabad,Pakistan
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作者 Fozia TABASSUM Muhammad RAIS +3 位作者 Maqsood ANWAR Tariq MEHMOOD Iftikhar HUSSAIN Shahid ALI KHAN 《Asian Herpetological Research》 SCIE 2011年第4期245-250,共6页
The population density and breeding of two frog species, i. e., the Skittering Frog (Euphlyctis eyanophlyctis) and the Bull Frog (Hoplobatrachus tigerinus) were studied at Rawal Lake, Islamabad, Pakistan, by using... The population density and breeding of two frog species, i. e., the Skittering Frog (Euphlyctis eyanophlyctis) and the Bull Frog (Hoplobatrachus tigerinus) were studied at Rawal Lake, Islamabad, Pakistan, by using visual encounter method from September 2009 to August 2010. Mean population density for the two frogs was 1.55 ± 0.44 frogs per ha, with that for the Skittering Frog being 1.09 ± 0.33 frogs/ha and that of the Bull Frog 0.46 ± 0.11 frog/ha, respectively. It is concluded that both frog species are explosive breeders, i. e., their breeding activities were confined to the first showers of the monsoon season. The mean spawn weight of the Skittering Frog was 1.5 g with more than 1000 eggs in each spawn, while that of the Bull Frog was 0.26 g with less than 1000 eggs in a spawn. The spawning sites of the two species were investigated in detail. Generally, no threat to their populations was observed. However, the opening of the spillway of Rawal Dam following the torrential rain destroyed the breeding sites of the frogs. It is maintained that the event did not produce any significant impact on their populations and breeding as the two species were quite common. 展开更多
关键词 RANIDAE population status breeding habitat destruction
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Recent changes in breeding abundance and distribution of the Common Pochard(Aythya ferina)in its eastern range
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作者 Alexander Mischenko Anthony David Fox +6 位作者 SauliusŠvažas Olga Sukhanova Alexandre Czajkowski Sergey Kharitonov Yuri Lokhman Oleg Ostrovsky Daiva Vaitkuvienė 《Avian Research》 CSCD 2020年第3期224-237,共14页
Background:The Common Pochard(Aythya ferina)(hereafter Pochard),a widespread and common freshwater diving duck in the Palearctic,was reclassified in 2015 from Least Concern to Vulnerable IUCN status based on rapid dec... Background:The Common Pochard(Aythya ferina)(hereafter Pochard),a widespread and common freshwater diving duck in the Palearctic,was reclassified in 2015 from Least Concern to Vulnerable IUCN status based on rapid declines throughout its range.Analysis of its status,distribution and the potential causes for the decline in Europe has been undertaken,but there has never been a review of its status in the major part of its breeding range across Russia to the Pacific coast.Methods:We reviewed the scientific literature and unpublished reports,and canvassed expert opinion throughout Russia to assess available knowledge about changes in the species distribution and abundance since the 1980s.Results:While accepting available information may not be representative throughout the entire eastern range of the species,the review found marked declines in Pochard breeding abundance in the last two decades throughout European Russia.Pochard have also declined throughout Siberia.Declines throughout the steppe region seemed related to local drought severity in recent years,necessitating further research to confirm this climate link at larger spatial scales.Declines in the forest and forest-steppe regions appeared related to the major abandonment of fish farms in western Russia that had formerly provided habitat for breeding Pochard.However,hyper-eutrophication of shallow eutrophic lakes,cessation of grazing and haymaking in floodplain systems necessary to maintain suitable nesting habitat and disappearance of colonies of the Black-headed Gull(Chroicocephalus ridibundus)in a number of wetlands were also implicated.Increasing invasive alien predator species(e.g.American Mink Neovison vison and Raccoon Dog Nyctereutes procyonoides)and increasing spring hunting were also thought to contribute to declines.Reports of expansion in numbers and range only came from small numbers occurring in the Russian Far East,including on the border with China and the long-established isolated population on Kamchatka Peninsula.Conclusions:Widespread declines throughout the eastern breeding range of the Pochard give continued cause for concern.Although we could address all the potential causal factors identified above by management interventions,we urgently need better information relating to key factors affecting site-specific Pochard breeding success and abundance,to be able to implement effective actions to restore the species to more favourable conservation status throughout its breeding range. 展开更多
关键词 Aythya ferina breeding Common Pochard population declines population stressors
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非直接选育对瓯江彩鲤形态性状的影响
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作者 王芙燕 柯景 +2 位作者 陈晓雯 王军 王成辉 《水产科技情报》 2024年第3期137-143,共7页
在鱼类育种中,体质量通常是直接选育的目标性状,形态性状因与体质量的相关性而受到非直接选育的影响。为探讨非直接选育对形态性状的影响,以体质量和体色为目标性状、经过11代闭锁群体继代选育的5种体色瓯江彩鲤(“全红”“大花”“麻... 在鱼类育种中,体质量通常是直接选育的目标性状,形态性状因与体质量的相关性而受到非直接选育的影响。为探讨非直接选育对形态性状的影响,以体质量和体色为目标性状、经过11代闭锁群体继代选育的5种体色瓯江彩鲤(“全红”“大花”“麻花”“粉玉”和“粉花”)选育系以及其奠基群体为材料,进行了与奠基群体形态性状相关的分析研究。单因素方差分析发现,在25个形态比例性状中,5个选育系有16~21个性状与奠基群体存在显著差异(P<0.05)。差异倍数分析显示,2个性状在所有选育系中上调明显,1个性状则下调明显。主成分分析显示,5个体色选育系均能与奠基群体明显区分开来;聚类分析发现,奠基群体的所有个体单独聚为一支,与5个选育系距离较远;判别分析指出,选育系与奠基群体间的判别准确率达100%。但以上分析均显示,5个选育系之间不能有效区分,相互间的形态差异较小。分析结果表明,非直接选育已对瓯江彩鲤的形态性状产生了较明显的影响。 展开更多
关键词 瓯江彩鲤 选育群体 奠基群体 多元统计分析 形态差异
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鞍带石斑鱼繁育群体的遗传多样性
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作者 龚师锐 王同 +4 位作者 宋乐龄 杨扬 钟朝岳 陶宇浩 刘晓春 《水产学报》 CAS CSCD 北大核心 2024年第4期203-211,共9页
为了解人工养殖和选育活动对鞍带石斑鱼遗传多样性的影响。本实验采用微卫星分子标记技术,对广东、海南和福建3个省份共5个代表性采集点的鞍带石斑鱼繁育群体的遗传变异信息进行了研究。群体内遗传多样性分析结果显示,5个群体等位基因(N... 为了解人工养殖和选育活动对鞍带石斑鱼遗传多样性的影响。本实验采用微卫星分子标记技术,对广东、海南和福建3个省份共5个代表性采集点的鞍带石斑鱼繁育群体的遗传变异信息进行了研究。群体内遗传多样性分析结果显示,5个群体等位基因(N_(a))的平均数目为7.326(6.375~8.380),观测杂合度(H_(o))平均值为0.711(0.625~0.775),期望杂合度(H_(e))平均值为0.705(0.684~0.734),多态性信息含量(PIC)平均值为0.659(0.633~0.693)。其中,来自福建厦门翔安区的鞍带石斑鱼繁育群体遗传多样性最高。分子方差分析(AMOVA)结果显示,5.36%的遗传变异来自群体间,95.45%来自所有个体间。群体间遗传分化指数(F_(st))及遗传距离结果显示,GC(感城)和CP(长坡)群体聚为一支,再与AT(澳头)群体聚为一支,然后与XA(翔安)群体聚为一支,HL(湖里)群体独立为一支。通过系统进化树分析显示,鞍带石斑鱼繁育群体交叉在一起,没有形成明显的地理格局分布。总之,这三省五地的鞍带石斑鱼繁育群体遗传多样性较高,没有明显的驯化迹象。研究表明,鞍带石斑鱼繁育群体仍具有较高的遗传多样性,品种受亲本近交影响而出现衰退的可能性不高,可排除因遗传因素导致的品种病害频发及养殖成活率低的原因。本研究可为鞍带石斑鱼种质评价和人工选育提供理论依据。 展开更多
关键词 鞍带石斑鱼 繁育群体 简单重复序列 SSR 遗传多样性 遗传结构
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长牡蛎(Crassostrea gigas)野生与选育群体的微卫星遗传多样性分析
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作者 李妍 姚健涛 +6 位作者 张恩烁 孙泽轩 孙国华 李彬 杨建敏 冯艳微 王卫军 《海洋与湖沼》 CAS CSCD 北大核心 2024年第2期462-470,共9页
为了评估长牡蛎(Crassostrea gigas)2个壳长性状(掌心形)快速生长选育群体(LY2-K4、LY2-K7)、1个壳高性状(速生型)快速生长选育群体(LY2-K11)和6个野生群体(QHD、LS、HD、ZH、WD、KTD)的遗传多样性和遗传结构,用21对多态性丰富的微卫星... 为了评估长牡蛎(Crassostrea gigas)2个壳长性状(掌心形)快速生长选育群体(LY2-K4、LY2-K7)、1个壳高性状(速生型)快速生长选育群体(LY2-K11)和6个野生群体(QHD、LS、HD、ZH、WD、KTD)的遗传多样性和遗传结构,用21对多态性丰富的微卫星引物对9个长牡蛎群体的269个个体进行了遗传分析。结果显示:21个微卫星位点共检测出了460个等位基因(Na),平均等位基因数为21.905;21个微卫星位点的多态信息含量(PIC)均大于0.5,具有高度遗传多态性;选育群体LY2-K11的遗传多样性最低(Na=13,I=2.128,He=0.831,PIC=0.825),野生群体KTD的遗传多样性最高(Na=29,I=3.112,He=0.941,PIC=0.938);189个群体位点组合有66%偏离哈代-温伯格平衡,表明这些群体存在一定程度的杂合子缺失;9个群体间的遗传分化指数(F_(st))为0.012~0.064,处于较低的遗传分化水平;AMOVA分析显示遗传变异主要来自于个体内;PCoA分析结果与UPGMA聚类树一致,LY2-K11群体单独聚为一类,QHD和HD群体聚为一类,其他6个群体聚为一类。综上所述,长牡蛎3个选育群体和6个野生群体遗传多样性均较高,遗传分化水平较低;选育群体LY2-K11多样性略有下降,选育过程中应保证亲本的数量及质量,防止因近交衰退造成遗传多样性降低,苗种抗逆性变差。该结果将为长牡蛎新品种的选育和野生种质资源的保护提供科学指导。 展开更多
关键词 长牡蛎(Crassostrea gigas) 选育群体 野生群体 微卫星 遗传多样性
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思南黄牛的品种介绍及开发利用对策研究
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作者 王军波 杨云 +2 位作者 郝明祥 杨涛 黎启红 《中国畜禽种业》 2024年第5期45-51,共7页
随着肉牛产业市场化和农业生产方式的转变,思南黄牛的群体数量呈现显著减少趋势,生存状况受到一定程度的威胁。该文简述了思南黄牛的历史记载、民间文化、产区条件、生物学特性、群体数量、杂交利用和加工销售情况,针对其群体数量减少... 随着肉牛产业市场化和农业生产方式的转变,思南黄牛的群体数量呈现显著减少趋势,生存状况受到一定程度的威胁。该文简述了思南黄牛的历史记载、民间文化、产区条件、生物学特性、群体数量、杂交利用和加工销售情况,针对其群体数量减少、种群衰退、产业链条短板等问题,提出了相应的对策建议,旨在为思南黄牛的品种保护、提纯复壮和扩繁利用提供参考借鉴,推动思南黄牛扩群增量,提升养殖效益。 展开更多
关键词 思南黄牛 品种介绍 种群衰退 开发利用
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济南市章丘区城乡蚊虫孳生环境及消杀的调查分析
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作者 车瑛 郑金萍 颜柱 《中国卫生标准管理》 2024年第13期31-34,共4页
目的分析济南市章丘区城乡蚊虫孳生环境及消杀现状,旨在为城乡环境的改善提供借鉴与指导。方法调查济南市章丘区2019年3月—2023年11月积水处、社区和农户家庭内外环境的蚊虫孳生情况,分析蚊幼虫密度、蚊虫种类,评价蚊虫孳生环境治理效... 目的分析济南市章丘区城乡蚊虫孳生环境及消杀现状,旨在为城乡环境的改善提供借鉴与指导。方法调查济南市章丘区2019年3月—2023年11月积水处、社区和农户家庭内外环境的蚊虫孳生情况,分析蚊幼虫密度、蚊虫种类,评价蚊虫孳生环境治理效果。结果2019年3月—2023年11月,每年各选取300个调查点,蚊幼虫阳性率分别为70%、42%、18%、6%、4%,蚊虫阳性率分别为42%、30%、12%、4%、2%,孳生蚊虫的积水处和容器数量逐年减少(P<0.05),蚊幼虫阳性率、蚊虫阳性率逐年下降(P<0.05)。2019—2023年济南市章丘区房屋指数(housing index,HI)、容器指数(container index,CI)、布雷图指数(Breitu index,BI)逐年下降(P<0.05)。2019—2023年共捕获1104只蚊虫样本,主要蚊虫种类包括淡色库蚊(43.03%)、白纹伊蚊(26.00%)、三带喙库蚊(11.96%)、中华按蚊(8.97%)。结论济南市章丘区城乡蚊虫孳生治理工作已经取得显著成效,蚊虫孳生情况有所改善,需要重点消杀淡色库蚊、白纹伊蚊、三带喙库蚊、中华按蚊等优势蚊种,为蚊媒疾病的控制奠定基础。 展开更多
关键词 城乡卫生环境 环境治理 蚊虫孳生 蚊虫消杀 种群分布 生态学监测
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Integrative demographic study of the Iberian painted frog(Discoglossus galganoi):inter-annual variation in the effective to census population size ratio,with insights on mating system and breeding success
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作者 Óscar OLARTE Gregorio SÁNCHEZ-MONTES Íñigo MARTÍNEZ-SOLANO 《Integrative Zoology》 SCIE CSCD 2020年第6期498-510,共13页
In the face of worldwide amphibian declines,integrative studies combining individual-based information and genetic data represent a powerful approach to produce robust,reliable,and comparable assessments of demographi... In the face of worldwide amphibian declines,integrative studies combining individual-based information and genetic data represent a powerful approach to produce robust,reliable,and comparable assessments of demographic dynamics.The Iberian painted frog(Discoglossus galganoi)is endemic to Spain and Portugal and shows decreasing population trends across its range,but few studies have attempted to estimate census sizes or assess genetic diversity in wild populations,and little is known about their reproductive biology.We applied an integrative approach based on the combination of capture-mark-recapture data and multilocus genotypes to monitor a breeding population of D.galganoi in central Spain during two consecutive breeding seasons,focusing on the estimation of demographic parameters and their temporal variation.Specifically,we estimated the number of adults(Na),the effective population size(Ne),and the effective number of breeders(Nb),as well as survival and migration rates.We documented a>50%decrease in the estimated number of adults of both sexes between the breeding seasons of 2018 and 2019,probably associated with reduced rainfall in the latter.Estimates of Nb and the Nb/Na ratio were low in both seasons,with a 20–30%decrease in Nb and a 47%increase in the Nb/Na ratio in 2019.Based on the reconstruction of pedigrees from larval and adult genotypes,we provide the first genetic evidence of polygamy in males and females of D.galganoi and the first estimates of breeding success in the species. 展开更多
关键词 AMPHIBIANS breeding success DEMOGRAPHY effective population size genetic diversity POLYGAMY
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