Mauremys mutica(Cantor,1842)is an endangered species in China.Main phenotypic variations inbody color,body weight,body shape,clutch size,egg size,and hatchling size were revealed betweenthe southern and northern popul...Mauremys mutica(Cantor,1842)is an endangered species in China.Main phenotypic variations inbody color,body weight,body shape,clutch size,egg size,and hatchling size were revealed betweenthe southern and northern populations.Both populations have the phenomenon of'larger male'sexualsize dimorphism(SSD),especially in the southern population.Furthermore,genetic variations betweenthe two populations were analyzed by RAPD band patterns of 30 random individuals in each population.The average genetic distance was 0.299±0.108 among the samples of two populations.The average ge-netic distance between southern and northern populations was 0.305±0.046.Cluster analysis indicatedthat all the individuals from the southern and northern populations were clustered among themselves toform two distinct clades.A total of 20 population-specific RAPD fragments were scored from 16 primers,and could be used as RAPD markers for distinguishing the southern and the northern population.Basedon the nucleotide sequences of two RAPD markers,two pairs of SCAR primers(SC1-S and SC2-S)weredesigned,which could be used as SCAR markers for the southern population.According to the significantphenotypic and genetic variations,we suggested that the northern population and southern populationmight be considered as two separate taxa,the'northern taxon'and the'southern taxon',and the con-servation should be respectively conducted on the two taxa.展开更多
Microbial communities in different gastrointestinal regions （stomach, foregut, midgut, and hindgut） of the northern snakehead Channa argus （Cantor, 1842） were compared by polymerase chain reaction and partial 16S ...Microbial communities in different gastrointestinal regions （stomach, foregut, midgut, and hindgut） of the northern snakehead Channa argus （Cantor, 1842） were compared by polymerase chain reaction and partial 16S rDNA sequencing. A total of 194, 140, 212, and 122 OTUs were detected in the stomach, foregut, midgut, and hindgut, respectively. Significant differences were found in the Sobs, ACE, Shannon, and Simpson indices among samples （P〈0.05）. The gastrointestinal microbial community of C. argus consisted predominantly of Proteobacteria with either Halomonas, Shewanella, Plesiomonas, or Sphingomonas. Fusobacteria, Firm!cutes, and Bacteroidetes also existed in the gastrointestinal tracts. However, significant＇differences were found in the compositions of microbial community among the four regions （P〈0.05）. Cyanobacteria and Spirochetes were significantly higher in the midgut and hindgut （P〈0.05）. Fusobacteria and Firmicutes were dominant in the hindgut and foregut, respectively （P〈0.05）. Proteobacteria was the lowest in the hindgut （P〈0.05）. At genus level, Cetobacterium and Plesiomonas were significantly higher in the hindgut than in the other three samples （P〈0.05）. Clostridium and Prevotella were the highest in the midgut （P〈0.05）. Halomonas, Shewanella, and Sphingomonas were the highest in the foregut （P〈0.05）. Paracoccus and Vibrio were the highest in the stomach. Several genera were only detected in certain regions, as follows： stomach, Paracoccus and Hbrio; foregut, Halomonas, Shewanella, and Sphingomonas; midgut, Clostridium and Prevotella; and hindgut, Cetobacterium and Plesiomonas （P〈0.05）. At the species level, Acinetobacter rhizosphaerae was only detected in the stomach. Prevotella copri and Clostridium perfring were not detected in the foregut and midgut, respectively, whereas Prevotella copri and Faecalibacterium pra were not detected in the hindgut. These findings provide valuable information on the microbial community in each gastrointestinal region of C. argus. Moreover, this study indicated that microbial community was not only related to rearing environment but also to the physico-chemical characteristics of each gastrointestinal region.展开更多
基金the National Basic Research Program of China(No.2004CB117405)the Key Research Program of Ocean and Fishery Bureau of Guangdong province(No.2001A09)
文摘Mauremys mutica(Cantor,1842)is an endangered species in China.Main phenotypic variations inbody color,body weight,body shape,clutch size,egg size,and hatchling size were revealed betweenthe southern and northern populations.Both populations have the phenomenon of'larger male'sexualsize dimorphism(SSD),especially in the southern population.Furthermore,genetic variations betweenthe two populations were analyzed by RAPD band patterns of 30 random individuals in each population.The average genetic distance was 0.299±0.108 among the samples of two populations.The average ge-netic distance between southern and northern populations was 0.305±0.046.Cluster analysis indicatedthat all the individuals from the southern and northern populations were clustered among themselves toform two distinct clades.A total of 20 population-specific RAPD fragments were scored from 16 primers,and could be used as RAPD markers for distinguishing the southern and the northern population.Basedon the nucleotide sequences of two RAPD markers,two pairs of SCAR primers(SC1-S and SC2-S)weredesigned,which could be used as SCAR markers for the southern population.According to the significantphenotypic and genetic variations,we suggested that the northern population and southern populationmight be considered as two separate taxa,the'northern taxon'and the'southern taxon',and the con-servation should be respectively conducted on the two taxa.
基金Supported by the National Natural Science Foundation of China(No.31402306)
文摘Microbial communities in different gastrointestinal regions （stomach, foregut, midgut, and hindgut） of the northern snakehead Channa argus （Cantor, 1842） were compared by polymerase chain reaction and partial 16S rDNA sequencing. A total of 194, 140, 212, and 122 OTUs were detected in the stomach, foregut, midgut, and hindgut, respectively. Significant differences were found in the Sobs, ACE, Shannon, and Simpson indices among samples （P〈0.05）. The gastrointestinal microbial community of C. argus consisted predominantly of Proteobacteria with either Halomonas, Shewanella, Plesiomonas, or Sphingomonas. Fusobacteria, Firm!cutes, and Bacteroidetes also existed in the gastrointestinal tracts. However, significant＇differences were found in the compositions of microbial community among the four regions （P〈0.05）. Cyanobacteria and Spirochetes were significantly higher in the midgut and hindgut （P〈0.05）. Fusobacteria and Firmicutes were dominant in the hindgut and foregut, respectively （P〈0.05）. Proteobacteria was the lowest in the hindgut （P〈0.05）. At genus level, Cetobacterium and Plesiomonas were significantly higher in the hindgut than in the other three samples （P〈0.05）. Clostridium and Prevotella were the highest in the midgut （P〈0.05）. Halomonas, Shewanella, and Sphingomonas were the highest in the foregut （P〈0.05）. Paracoccus and Vibrio were the highest in the stomach. Several genera were only detected in certain regions, as follows： stomach, Paracoccus and Hbrio; foregut, Halomonas, Shewanella, and Sphingomonas; midgut, Clostridium and Prevotella; and hindgut, Cetobacterium and Plesiomonas （P〈0.05）. At the species level, Acinetobacter rhizosphaerae was only detected in the stomach. Prevotella copri and Clostridium perfring were not detected in the foregut and midgut, respectively, whereas Prevotella copri and Faecalibacterium pra were not detected in the hindgut. These findings provide valuable information on the microbial community in each gastrointestinal region of C. argus. Moreover, this study indicated that microbial community was not only related to rearing environment but also to the physico-chemical characteristics of each gastrointestinal region.
