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Paiboon Sithithaworn - One of the best experts on this subject based on the ideXlab platform.
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infection dynamics of opisthorchis viverrini metacercariae in cyprinid fishes from two endemic areas in thailand and lao pdr
American Journal of Tropical Medicine and Hygiene, 2020Co-Authors: Jutamas Namsanor, Trevor N. Petney, Ross H. Andrews, Nadda Kiatsopit, Thewarach Laha, Paiboon SithithawornAbstract:The infection dynamics of Opisthorchis viverrini metacercariae was analyzed in cyprinid fish from endemic areas in Mukdahan Province, Thailand, and Khammouane Province, Lao PDR. The fish were collected during the cool-dry (November-February), hot-dry (March-May), and rainy (June-October) seasons in 2017. They were examined by the digestion method, and the infection status was statistically analyzed by study area, season, and fish size. The prevalence (no. of fish positive/no. of fish examined × 100) and metacercarial intensities (no. of metacercariae detected/no. of fish positive) of O. viverrini in both study areas depended on season, being high in the cool-dry season and varying in the hot-dry and rainy seasons. In Mukdahan Province, the average prevalence was 18.3% (range 11.0-46.7%, n = 420) and the intensity was 4.07 ± 5.86 cysts/fish (mean ± SD), whereas in Khammouane Province, the prevalence was 51.9% (range 9.1-70.6%, n = 673) and the intensity was 6.67 ± 12.88 cysts/fish. Among the cyprinid fish species examined, the infection was associated with fish body size and predominantly found in Hampala dispar (86.5%), Cyclocheilichthys armatus (73.2%), and Puntius brevis (42.7%). The distribution of O. viverrini metacercariae in fish was skewed, with most of the fish having a low worm burden with an average of four to six cysts/fish. The findings that seasonality, sampling locality, fish size, and species of fish play roles in the risk of O. viverrini infection imply that these host and environmental factors are important for the transmission dynamics and control of O. viverrini.
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Impact of temporal changes and host factors on the genetic structure of a population of Opisthorchis viverrini sensu lato in Khon Kaen Province (Thailand)
Parasitology, 2009Co-Authors: Weerachai Saijuntha, Paiboon Sithithaworn, Neil B. Chilton, Trevor N. Petney, Sirawut Klinbunga, Rojchai Satrawaha, Joanne P. Webster, Ross H. AndrewsAbstract:The population genetics of 317 individual Opisthorchis viverrini from Khon Kaen Province Thailand, from 4 different years and 4 cyprinid fish species was examined using multilocus enzyme electrophoresis of enolase (Enol), phosphoglucomutase (Pgm) and triose phosphate isomerase (Tpi). Allele and genotype frequencies for Enol and Pgm were consistent irrespective of year or host species. No heterozygote deficiency was detected for Enol. Significant heterozygote deficiencies were detected in 3 of 4 years for Pgm. For Tpi, allele frequencies of the most common allele and genotype frequency varied between years and among individuals from different host species. Heterozygote deficiencies for Tpi were detected in 2 years. No significant heterozygous deficiencies were detected among O. virerrini from different fish species in 2005, except at Pgm and Tpi from Puntioplites protozsron. There was no statistical significance in pairwise F ST values between O. viverrini from Cyclocheilichthys armatus in different years or different host species in 2005. Significant departures from Hardy-Weinberg expectations and a high rate of gene flow in a population of O. viverrini are discussed in terms of self- and cross-fertilisation, natural selection, non-random mating, the Wahlund effect, presence of null alleles, intensity of infection, biology and ecology of their intermediate cyprinid hosts.
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Seasonal Variation of Opisthorchis Viverrini Infection in Cyprinoid Fish in North-East Thailand: Implications for Parasite Control and Food Safety
Bulletin of the World Health Organization, 1997Co-Authors: Paiboon Sithithaworn, V. Pipitgool, Tuanchai Srisawangwong, D. B. Elkins, Melissa Haswell-elkinsAbstract:Reported is the seasonal pattern of Opisthorchis viverrini metacercariae in cyprinoid fish in north-east Thailand. Samples of fish were collected in 1991-92 at monthly intervals from two areas-Khon Kaen Province, where the opisthorchiasis transmission rate was high, and Mahasarakham Province, where the rate was low. Metacercarial loads in both study areas had similar seasonal patterns. High burdens occurred in the late rainy season and winter (July to January) with low burdens during the summer (March to June). The average burden for Puntius leiacanthus in Khon Kaen was 1.68 metacercariae per fish (127.43 per kg), higher than for all species of cyprinoid fish from the low transmission area. The intensities of infection among P. leiacanthus and Cyclocheilichthys armatus collected in Mahasarakham were comparable, but lower than the intensity of Hampala dispar (0.75 metacercariae per fish) concurrently sampled from the same area (P < 0.05). There was no significant difference in metacercarial load per kg between fish species from Mahasarakham. The results indicate that seasonal variation in metacercariae was a common phenomenon in areas with both high and low endemicity of infection. Also, the metacerarial load in fish was positively associated with infection levels among humans.
Ross H. Andrews - One of the best experts on this subject based on the ideXlab platform.
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infection dynamics of opisthorchis viverrini metacercariae in cyprinid fishes from two endemic areas in thailand and lao pdr
American Journal of Tropical Medicine and Hygiene, 2020Co-Authors: Jutamas Namsanor, Trevor N. Petney, Ross H. Andrews, Nadda Kiatsopit, Thewarach Laha, Paiboon SithithawornAbstract:The infection dynamics of Opisthorchis viverrini metacercariae was analyzed in cyprinid fish from endemic areas in Mukdahan Province, Thailand, and Khammouane Province, Lao PDR. The fish were collected during the cool-dry (November-February), hot-dry (March-May), and rainy (June-October) seasons in 2017. They were examined by the digestion method, and the infection status was statistically analyzed by study area, season, and fish size. The prevalence (no. of fish positive/no. of fish examined × 100) and metacercarial intensities (no. of metacercariae detected/no. of fish positive) of O. viverrini in both study areas depended on season, being high in the cool-dry season and varying in the hot-dry and rainy seasons. In Mukdahan Province, the average prevalence was 18.3% (range 11.0-46.7%, n = 420) and the intensity was 4.07 ± 5.86 cysts/fish (mean ± SD), whereas in Khammouane Province, the prevalence was 51.9% (range 9.1-70.6%, n = 673) and the intensity was 6.67 ± 12.88 cysts/fish. Among the cyprinid fish species examined, the infection was associated with fish body size and predominantly found in Hampala dispar (86.5%), Cyclocheilichthys armatus (73.2%), and Puntius brevis (42.7%). The distribution of O. viverrini metacercariae in fish was skewed, with most of the fish having a low worm burden with an average of four to six cysts/fish. The findings that seasonality, sampling locality, fish size, and species of fish play roles in the risk of O. viverrini infection imply that these host and environmental factors are important for the transmission dynamics and control of O. viverrini.
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Impact of temporal changes and host factors on the genetic structure of a population of Opisthorchis viverrini sensu lato in Khon Kaen Province (Thailand)
Parasitology, 2009Co-Authors: Weerachai Saijuntha, Paiboon Sithithaworn, Neil B. Chilton, Trevor N. Petney, Sirawut Klinbunga, Rojchai Satrawaha, Joanne P. Webster, Ross H. AndrewsAbstract:The population genetics of 317 individual Opisthorchis viverrini from Khon Kaen Province Thailand, from 4 different years and 4 cyprinid fish species was examined using multilocus enzyme electrophoresis of enolase (Enol), phosphoglucomutase (Pgm) and triose phosphate isomerase (Tpi). Allele and genotype frequencies for Enol and Pgm were consistent irrespective of year or host species. No heterozygote deficiency was detected for Enol. Significant heterozygote deficiencies were detected in 3 of 4 years for Pgm. For Tpi, allele frequencies of the most common allele and genotype frequency varied between years and among individuals from different host species. Heterozygote deficiencies for Tpi were detected in 2 years. No significant heterozygous deficiencies were detected among O. virerrini from different fish species in 2005, except at Pgm and Tpi from Puntioplites protozsron. There was no statistical significance in pairwise F ST values between O. viverrini from Cyclocheilichthys armatus in different years or different host species in 2005. Significant departures from Hardy-Weinberg expectations and a high rate of gene flow in a population of O. viverrini are discussed in terms of self- and cross-fertilisation, natural selection, non-random mating, the Wahlund effect, presence of null alleles, intensity of infection, biology and ecology of their intermediate cyprinid hosts.
Laurent Viriot - One of the best experts on this subject based on the ideXlab platform.
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resurrection of the genus Anematichthys (Bleeker 1859), based on morphological and molecular data of Southeast Asian Cyprininae (Teleostei, Cypriniformes)
2013Co-Authors: Emmanuel Pasco-viel, Monette Veran, Laurent ViriotAbstract:Bleeker was right: Revision of the genus Cyclocheilichthys (Bleeker 1859) an
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Comments on ‘The valid generic names for the fish species usually placed in Cyclocheilichthys ’ (KOTTELAT 2013) and a correction of Pasco-viel et al. (2012)
Zootaxa, 2013Co-Authors: Emmanuel Pasco-viel, Monette Veran, Laurent ViriotAbstract:As authors of the study demonstrating the non-monophyly of the genus previously called Cyclocheilichthys (Pasco-Viel et al . 2012), which included nine species, we acknowledge Kottelat’s (2013: this issue) conclusions with regard to the generic names for the species we investigated: cu� o������g pincer-shaped suckers, is described for the first time using scanning electron microscopy. In scolex morphology, M. ficta closely resembles phyllobothriidean cestodes, parasites of elasmobranchs. However, this similarity does not reflect phylogenetic relatedness of these cestodes but instead presents an example of convergent morphological evolution of attachment organs of unrelated groups of cestodes that parasitize different groups of vertebrates. Besides scolex morphology, the genus is characterised by the possession of a very large cirrus-sac, which may reach up to the midline of proglottides, few testes (less than 60), vitelline follicles limited to the dorsal side of proglottides, a large vaginal sphincter, and eggs with a three-layered embryophore covered with rounded projections. Numerous errors in the diagnosis of M. ficta , which appeared in the literature as a result of uncritical compilation of data without examination of original material, are corrected. Multilocus phylogenetic analysis of nuclear ribosomal RNA genes ssr - and lsrDNA and mitochondrial genes rrnL and cox1 place this species among other snake-parasitizing proteocephalideans of the genus Ophiotaenia . The convergent evolution of scolex morphology across distantly related taxa is discussed.
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comments on the valid generic names for the fish species usually placed in Cyclocheilichthys kottelat 2013 and a correction of pasco viel et al 2012
Zootaxa, 2013Co-Authors: Emmanuel Pascoviel, Monette Veran, Laurent ViriotAbstract:As authors of the study demonstrating the non-monophyly of the genus previously called Cyclocheilichthys (Pasco-Viel et al . 2012), which included nine species, we acknowledge Kottelat’s (2013: this issue) conclusions with regard to the generic names for the species we investigated: cu� o������g pincer-shaped suckers, is described for the first time using scanning electron microscopy. In scolex morphology, M. ficta closely resembles phyllobothriidean cestodes, parasites of elasmobranchs. However, this similarity does not reflect phylogenetic relatedness of these cestodes but instead presents an example of convergent morphological evolution of attachment organs of unrelated groups of cestodes that parasitize different groups of vertebrates. Besides scolex morphology, the genus is characterised by the possession of a very large cirrus-sac, which may reach up to the midline of proglottides, few testes (less than 60), vitelline follicles limited to the dorsal side of proglottides, a large vaginal sphincter, and eggs with a three-layered embryophore covered with rounded projections. Numerous errors in the diagnosis of M. ficta , which appeared in the literature as a result of uncritical compilation of data without examination of original material, are corrected. Multilocus phylogenetic analysis of nuclear ribosomal RNA genes ssr - and lsrDNA and mitochondrial genes rrnL and cox1 place this species among other snake-parasitizing proteocephalideans of the genus Ophiotaenia . The convergent evolution of scolex morphology across distantly related taxa is discussed.
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Bleeker was right: Revision of the genus Cyclocheilichthys (Bleeker 1859) and resurrection of the genus Anematichthys (Bleeker 1859), based on morphological and molecular data of Southeast Asian Cyprininae (Teleostei, Cypriniformes)
Zootaxa, 2012Co-Authors: Emmanuel Pasco-viel, Monette Veran, Laurent ViriotAbstract:The taxonomy within the order Cypriniformes is subject to frequent changes, thanks to the results coming from recent molecular phylogenies that help understand the Cypriniformes tree of life previously established through morphological characters. In this paper, we focus on species belonging to the Cyprininae – the largest sub-family among Cypriniformes – and we present both morphological and phylogenetic arguments to revise the taxonomy of the genus Cyclocheilichthys. For morphological investigations, we characterized external traits as well as the postcranial skeleton and the neurocranium. For molecular phylogenies, we used four markers, both mitochondrial and nuclear, to establish a phylogenetic tree. We studied four species currently assigned to the genus Cyclocheilichthys as well as the species Cosmochilus harmandi and Puntioplites falcifer and we show that the genus Cyclocheilichthys is non-monophyletic as Cyclocheilichthys enoplos is closer to C. harmandi and P. falcifer than Cyclocheilichthys armatus, Cyclocheilichthys apogon and Cyclocheilichthys repasson. Finally, we revise the genus Cyclocheilichthys and we propose to split this genus into two genera: genus Cyclocheilichthys with the species Cyclocheilichthys enoplos and genus Anematichthys with species Anematichthys armatus, Anematichthys apogon and Anematichthys repasson.
Maurice Kottelat - One of the best experts on this subject based on the ideXlab platform.
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The valid generic names for the fish species usually placed in Cyclocheilichthys (Pisces: Cyprinidae).
Zootaxa, 2013Co-Authors: Maurice KottelatAbstract:Cyclocheilichthys is the valid name for the genus that includes Barbus apogon Valenciennes. Cyclocheilichthys has precedence over Anematichthys , which is a simultaneous objective synonym. If C. enoplos is considered not to be congeneric with C. apogon , the valid name for a genus that includes it is Cyclocheilos .
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Cyclocheilichthys SCHOPPEAE, A NEW SPECIES OF FRESHWATER FISH (TELEOSTEI: CYPRINIDAE) FROM NORTHERN PALAWAN, PHILIPPINES
2007Co-Authors: Miguelito Cervancia, Maurice KottelatAbstract:Cyclocheilichthys schoppeae, new species, is described from the Abongan and Barbacan river basins in northern Palawan. It is distinguished from all its congeners by having 12 circumpeduncular scale rows (vs. 16-22). It is further distinguished by having 26 circumferential scale rows, 6-7 rows of black spots along the flank, no black spot at caudal fin base, two pairs of barbels, the lateral line tubes not branched and no midlateral stripe. The status of the present knowledge on Palawan's freshwater fish fauna is briefly commented.
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nomenclature of the genera barbodes Cyclocheilichthys rasbora and chonerhinos teleostei cyprinidae and tetraodontidae with comments on the definition of the first reviser
1999Co-Authors: Maurice KottelatAbstract:Problems resulting from a difference of definition of the first reviser between the English and French versions of 1985 edition of the International Code of Zoological Nomenclature are discussed. Barbodes belinka Bleeker, 1860 cannot be the type species of Barbodes Bleeker, 1859; Barbus maculatus Valenciennes, 1842 is designated as type species. The species previously placed in Barbodes are now to be called Barbonymus, new genus. Barbus apogon Valenciennes, 1842 is the simultaneous type species of Cyciocheilichthys Bleeker, 1859 and Anematichthys Bleeker, 1859. Cyciocheilos Bleeker, 1859 is a senior subjective synonym of Cyciocheilichthys; its type species is Barbus macracanthus Bleeker, 1853. Leuciscus cephalotaenia Bleeker, 1853 is the type species of Rasbora Bleeker, 1859. The type species of Chonerhinos Bleeker, 1854 is Tetraodon naritus Richardson, 1848; Chonerhinos is a senior subjective synonym of Xenoptere Bibron, 1855 (Xenopterus auct.). The species previously placed in Chonerhinos are now called Auriglobus, new genus. While compiling a list of Oriental fishes and their synonyms, I came accross a number of nomenclatural problems. The resolution of most of these problems has little or no impact on the names used for these fishes, others have. I discuss here four such cases. As the concept of first reviser plays an important role in the resolution of these cases, it is unfortunately also necessary to discuss the definition of the first reviser since the International Code of Zoological Nomenclature (1985 edition; hereunder the Code) includes two partly contradictory definitions.
Banchob Sripa - One of the best experts on this subject based on the ideXlab platform.
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New locality record for Haplorchoides mehrai and possible interactions with Opisthorchis viverrini metacercariae in cyprinid fishes in Northeast Thailand
Parasitology Research, 2017Co-Authors: Yupin Manpratum, Pierre Echaubard, Wanlop Kaewkes, Banchob Sripa, Sasithorn KaewkesAbstract:Metacercariae of Opisthorchis viverrini , a carcinogenic liver fluke, and Haplorchoides sp., a trematode maturing in catfish, are commonly found in cyprinid fish, the second intermediate hosts of both flukes. However, the specific identity of Haplorchoides sp. in Thailand and a precise assessment of the effects of co-infections with O. viverrini have never been clarified. Therefore, we aimed to identify the species of Haplorchoides and to investigate possible interactions of the two trematode species in cyprinid fishes. Based on the morphology and morphometry of the cercaria, metacercaria, and adult stages, the Haplorchoides species found was identified as Haplorchoides mehrai Pande and Shukla 1976 . Thailand is formally recorded as a new locality for H. mehrai , where naturally infected hosts include the snail Melanoides tuberculata (first intermediate host), the cyprinid fishes Hampala dispar , Cyclocheilichthys apogon , Puntius leiacanthus , Labiobarbus burmanicus , and Cirrhina jullieni (second intermediate hosts), and a catfish, Mystus nemurus (definitive host). The co-infection rates of O. viverrini and H. mehrai were significantly associated with fish species and fish body region ( P
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carcinogenic human liver fluke current status of opisthorchis viverrini metacercariae in nakhon ratchasima thailand
Asian Pacific Journal of Cancer Prevention, 2012Co-Authors: Natthawut Kaewpitoon, Soraya J Kaewpitoon, Naporn Uengarporn, Ratana Rujirakul, Seekaow Churproong, Likit Matrakool, Suprakrit Auiwatanagul, Banchob SripaAbstract:Background: Opisthorchis viverrini infection is a serious public-health problem in Southeast Asia. It is associated with a number of hepatobiliary diseases and the evidence strongly indicates that liver fluke infection is the etiology of cholangiocarcinoma. Objectives: This study aimed to investigate Opisthorchis viverrini metacercarial infection in cyprinoid fish collected from 32 districts of Nakhon Ratchasima province, Northeastern Thailand during one year period from February 2010 to February 2011. Methods: A cross-sectional study was conducted, data being collected with pepsin-HCl digestion and stereomicroscope, respectively. Analysis was performed using SPSS Windows Version 12.0. Results: A total of 640 Cyprinidae family fish including 5 species were collected from different study sites, and investigated for O. viverrini metacercariae. The infection rate was 12.3% (79/640), predominantly in Cyclocheilichthys armatus, C. repasson, Puntioplites proctzysron, Hampala macrolepitota and Hampala dispar, respectively. The prevalence of O. viverrini metaceria in Nakhon Ratchasima area was 78.1%, predominantly in Sida and KiaKham Thale So. Conclusion: This findings stress that natural fish species in rural communities are still a source of O viverrini infection and put local people at risk, therefore public awareness and prevention campaigns are urgently required.
