Seasonal Abundance and Distribution of Vibrio cholerae in Coastal Waters Quantified by a 16S-23S Intergenic Spacer Probe

2001 ◽  
Vol 42 (4) ◽  
pp. 540-548 ◽  
Author(s):  
S.C. Jiang ◽  
W. Fu
Keyword(s):  
Vibrio Cholerae ◽  
Coastal Waters ◽  
Intergenic Spacer ◽  
Seasonal Abundance ◽  
Abundance And Distribution

scholarly journals Seasonal abundance and distribution of phytoplankton in Tanintharyi coastal waters, southern Myanmar

Bionatura ◽  
2020 ◽  
Vol 5 (3) ◽  
pp. 1203-1208
Author(s):  
Khin Khin Gyi ◽  
Wint Thuzar Nwe ◽  
Zin Zin Zaw ◽  
Khin Khin San
Keyword(s):  
Coastal Waters ◽  
Sharp Increase ◽  
Species Abundance ◽  
Water Clarity ◽  
Freshwater Discharge ◽  
Seasonal Abundance ◽  
Phytoplankton Abundance ◽  
Cell Abundance ◽  
Abundance And Distribution ◽  
Wide Fluctuation

The seasonal abundance and distribution of phytoplankton along the Tanintharyi coastal waters were investigated for 24 months from June 2013 to June 2015. A wide fluctuation in cell abundance 72,450-714,396 cells/l at Kawthaung, 47,416-947,501 cells/l at Myeik, 8,930-28,439 cells/l at Kampani, 8,976-17,888 cells/l at Ye and 5,162-16,986 cells/l at Setse were noted during the study period. Amongst, Kawthaung and Myeik stations had the highest phytoplankton abundance, whereas Ye and Setse stations showed remarkably lower abundance. It was noted that Ye and Setse stations were much influenced by freshwater discharge from the Thanlwin River, which deposited huge tons of sediments. The water clarity was lower at these stations compare with others. Therefore, turbidity may affect the occurrence and species abundance of phytoplankton. A clear seasonal trend was found at all five stations with a sharp increase in the pre-monsoon months and a gradual decrease in the monsoon and post-monsoon periods. Keywords: phytoplankton, Tanintharyi, water clarity, turbidity,

Dynamic Subspecies Population Structure of Vibrio Cholerae in Dhaka, Bangladesh

2021 ◽  
Author(s):  
Mohammad Islam ◽  
Tania Nasreen ◽  
Kevin Y. H. Liang ◽  
Fatema-Tuz Johura ◽  
Paul C. Kirchberger ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Temporal Dynamics ◽  
Sampling Period ◽  
Amplicon Sequencing ◽  
Rapid Expansion ◽  
Capital City ◽  
Dhaka City ◽  
Physiochemical Parameters ◽  
Subspecies Level ◽  
Abundance And Distribution

Abstract Cholera has been endemic to the Ganges delta for centuries. Although the causative agent, Vibrio cholerae, is autochthonous to coastal and brackish water, cholera occurs continually in Dhaka, the inland capital city of Bangladesh which is surrounded by fresh water. Despite the persistence of this problem, little is known about the environmental abundance and distribution of lineages of V. cholerae, the most important being the pandemic generating lineage (PG) consisting mostly of serogroup O1 strains. To understand spatial and temporal dynamics of PG and other lineages belonging to the V. cholerae species in surface water in and around Dhaka city, we used qPCR and high throughput amplicon sequencing. Seven different freshwater sites across Dhaka were investigated for six consecutive months and physiochemical parameters were measured in situ. Total abundance of V. cholerae was found to be relatively stable throughout the six months sampling period, with 2×105 to 4×105 genome copies/L at six sites and around 5 ×105 genome copies/L at the site located in the most densely populated part of Dhaka city. PG O1 V. cholerae was present in high abundance during the entire sampling period and composed between 24-92% of the total V. cholerae population, only showing occasional but sudden reductions in abundance. In instances where PG O1 lost its dominance, other lineages underwent a rapid expansion while the size of the total V. cholerae population remained almost unchanged. Intraspecies richness of V. cholerae was positively correlated to salinity, conductivity and total dissolved solids (TDS), while it was negatively correlated to dissolved oxygen (DO) concentration in water. Interestingly, negative correlation was observed specifically between PG O1 and salinity, even though the changes in this variable were minor (0-0.8 ppt). Observations in this study suggest that at the subspecies level, population composition of naturally occurring V. cholerae can be influenced by fluctuations in environmental factors, which can lead to altered competition dynamics among the lineages.

scholarly journals Molecular characterization of Aeromonas spp. and Vibrio cholerae O1 isolated during a diarrhea outbreak

2012 ◽  
Vol 54 (6) ◽  
pp. 299-304 ◽  
Author(s):  
Carina Lucena Mendes-Marques ◽  
Larissa Mélo do Nascimento ◽  
Grace Nazareth Diogo Theophilo ◽  
Ernesto Hofer ◽  
Osvaldo Pompílio de Melo Neto ◽  
...  
Keyword(s):  
Vibrio Cholerae ◽  
Intergenic Spacer ◽  
Abundant Species ◽  
Environmental Isolates ◽  
Pathogenic Potential ◽  
Intergenic Spacer Region ◽  
Clonal Relatedness ◽  
Pathogenic Genes ◽  
Vibrio Cholerae O1 ◽  
Definition Of

This work aimed to assess pathogenic potential and clonal relatedness of Aeromonas sp. and Vibrio cholerae isolates recovered during a diarrhea outbreak in Brazil. Clinical and environmental isolates were investigated for the presence of known pathogenic genes and clonal relatedness was assessed by intergenic spacer region (ISR) 16S-23S amplification. Four Aeromonas genes (lip, exu, gcat, flaA/B) were found at high overall frequency in both clinical and environmental isolates although the lip gene was specifically absent from selected species. A fifth gene, aerA, was rarely found in A. caviae, the most abundant species. The ISR profile revealed high heterogeneity among the Aeromonas isolates and no correlation with species identification. In contrast, in all the V. cholerae isolates the four genes investigated (ctxA, tcpA, zot and ace) were amplified and revealed homogeneous ISR and RAPD profiles. Although Aeromonas isolates were the major enteric pathogen recovered, their ISR profiles are not compatible with a unique cause for the diarrhea events, while the clonal relationship clearly implicates V. cholerae in those cases from which it was isolated. These results reinforce the need for a better definition of the role of aeromonads in diarrhea and whether they benefit from co-infection with V. cholerae.

scholarly journals Age and growth of Callionymus lyra L.

1951 ◽  
Vol 30 (2) ◽  
pp. 281-296 ◽  
Author(s):  
Hsiao-Wei Chang
Keyword(s):  
Seasonal Variation ◽  
Sexual Dimorphism ◽  
West Africa ◽  
Economic Importance ◽  
Age And Growth ◽  
Seasonal Abundance ◽  
The Common ◽  
Abundance And Distribution ◽  
Median Fins ◽  
European Seas

The Common Dragonet, Callionymus lyra L., is one of the commonest fishes in the Plymouth area, and is widely distributed in European seas. Recent reports indicate that it occurs also off the coast of West Africa (Fowler, 1936; Poll, 1949). This fish, like others of the genus, attracts attention because, although it has very little economic importance, it is strikingly coloured and the sexes are markedly different. Work has been done on the breeding by Holt (1897, 1898), and by Holt & Scott (1898); on ova and larvae by M'Intosh (1885), M'Intosh & Prince (1889), Cunningham (1891), Holt (1897), Ehrenbaum (1905–9), Fage (1918), Mielck (1925), Duncker, Ehrenbaum, Kyle, Mohr & Schnakenbeck (1929); on seasonal abundance and distribution of post-larvae off Plymouth by Russell (1930–47) and Corbin (1948); and on the skeleton by Günther (1861) and Ford (1937). The mature males are provided with remarkable secondary sexual characters both in coloration and in relative lengths of snout and of median fins, which render them so different from the females that they were originally regarded as different species and known as the Gemmeous Dragonet (male C. lyra L.) and the Sordid Dragonet (female C. lyra L.=C. dracunculus L.) respectively (Donovan, 1808; Yarrell, 1859; Couch, 1863). The sexual dimorphism and seasonal variation of this species has been much studied by Holt (1898), Smitt (1892–95), Gallien (1934), Letaconnoux (1949) and Desbrosses (1949). Very little information has so far been provided about its age and growth, with which the present paper deals.

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