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Brian H. Kay - One of the best experts on this subject based on the ideXlab platform.
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ELIMINATION OF DENGUE BY COMMUNITY PROGRAMS USING Mesocyclops
2015Co-Authors: Le Trung Nghia, Peter A Ryan, Ahmet Bektas, Alistair Briscombe, John G. Aaskov, Brian H. KayAbstract:Abstract. From September 2000 to June 2003, a community-based program for dengue control using local predacious copepods of the genus Mesocyclops was conducted in three rural communes in the central Vietnam provinces of Quang Nam, Quang Ngai, and Khanh Hoa. Post-project, three subsequent entomologic surveys were conducted until March 2004. The number of households and residents in the communes were 5,913 and 27,167, respectively, and dengue notification rates for these communes from 1996 were as high as 2,418.5 per 100,000 persons. Following knowledge, attitude, and practice evaluations, surveys of water storage containers indicated that Mesocyclops spp. already occurred in 3–17 % and that large tanks up to 2,000 liters, 130−300-liter jars, wells, and some 220-liter metal drums were the most productive habitats for Aedes aegypti. With technical support, the programs were driven by communal management committees, health collaborators, schoolteachers, and pupils. From quantitative estimates of the standing crop of third and fourth instars from 100 households, Ae. aegypti were reduced by approximately 90 % by year 1, 92.3−98.6 % by year 2, and Ae. aegypti immature forms had been eliminated from two of three communes by June 2003. Similarly, from resting adult collections from 100 households, densities were reduced to 0–1 per commune. By March 2004, two communes with no larvae had small numbers but the third was negative; one adult was collected in each of two communes while one became negative. Absolute estimates of third and fourth instars at the three intervention com-munes and one left untreated had significant correlations (P 0.009−< 0.001) with numbers of adults aspirated fro
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control of aedes vectors of dengue in three provinces of vietnam by use of Mesocyclops copepoda and community based methods validated by entomologic clinical and serological surveillance
American Journal of Tropical Medicine and Hygiene, 2002Co-Authors: Brian H. Kay, Vu Sinh Nam, Tran Van Tien, Nguyen Thi Yen, Tran Vu Phong, Vu Thi Bich Diep, Truong Uyen Ninh, Ahmet Bektas, John AaskovAbstract:We describe remarkable success in controlling dengue vectors, Aedes aegypti (L.) and Aedes albopictus (Skuse), in 6 communes with 11,675 households and 49,647 people in the northern provinces of Haiphong, Hung Yen, and Nam Dinh in Vietnam. The communes were selected for high-frequency use of large outdoor concrete tanks and wells. These were found to be the source of 49.6-98.4% of Ae. aegypti larvae, which were amenable to treatment with local Mesocyclops, mainly M. woutersi Van der Velde, M. aspericornis (Daday) and M. thermocyclopoides Harada. Knowledge, attitude, and practice surveys were performed to determine whether the communities viewed dengue and dengue hemorrhagic fever as a serious health threat; to determine their knowledge of the etiology, attitudes, and practices regarding control methods including Mesocyclops; and to determine their receptivity to various information methods. On the basis of the knowledge, attitude, and practice data, the community-based dengue control program comprised a system of local leaders, health volunteer teachers, and schoolchildren, supported by health professionals. Recycling of discards for economic gain was enhanced, where appropriate, and this, plus 37 clean-up campaigns, removed small containers unsuitable for Mesocyclops treatment. A previously successful eradication at Phan Boi village (Hung Yen province) was extended to 7 other villages forming Di Su commune (1,750 households) in the current study. Complete control was also achieved in Nghia Hiep (Hung Yen province) and in Xuan Phong (Nam Dinh province); control efficacy was > or = 99.7% in the other 3 communes (Lac Vien in Haiphong, Nghia Dong, and Xuan Kien in Nam Dinh). Although tanks and wells were the key container types of Ae. aegypti productivity, discarded materials were the source of 51% of the standing crop of Ae. albopictus. Aedes albopictus larvae were eliminated from the 3 Nam Dinh communes, and 86-98% control was achieved in the other 3 communes. Variable dengue attack rates made the clinical and serological comparison of control and untreated communes problematic, but these data indicate that clinical surveillance by itself is inadequate to monitor dengue transmission.
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the importance of subterranean mosquito habitat to arbovirus vector control strategies in north queensland australia
Journal of Medical Entomology, 2000Co-Authors: Brian H. Kay, Scott A Lyons, J S Holt, Bruce Russell, Peter A Ryan, P N FoleyAbstract:In north Queensland, 14 localities were surveyed for mosquito larvae (third and fourth instar) during summer/autumn and winter from 1996 to 1999. Absolute population numbers in subterranean habitats, mainly service manholes and pits (97%) but also some wells, septic tanks, storm drains, and sumps, were expressed as a proportion of total numbers in these sites plus surface sites within a 100-m radius. When correction factors were applied to subterranean samples, the 472,477 larvae mainly of Aedes tremulus (Theobald) group, Aedes notoscriptus (Skuse), and Aedes aegypti (L.) comprised 78% of the total population. In relation to the proportion of the overall immature mosquito population from subterranean habitats (propsub), linear regression coefficients for minimum temperature, relative humidity, and Mesocyclops copepod prevalence were significant for winter data; but for summer, only relative humidity was significant. Linear regression coefficients for Mesocyclops prevalence approached significance (P = 0.061) in summer. When multiple linear regression was used to model propsub, 68% of the variation was accounted for by relative humidity and the prevalence of Mesocyclops. In the drier and cooler towns, increased use of subterranean sites during winter was caused by reduced availability of surface oviposition sites because of the dry season. In the wetter coastal towns, no such restrictions applied and ambient conditions remained more equitable all year round. Mesocyclops were surprisingly common, particularly in these coastal towns. Release of known numbers of Mesocyclops indicated that 3-sweep netting in service manholes was sensitive down to densities of one Mesocyclops per 10 liters, and overall recovery varied from 1 to 4%. In relation to control, service manholes represent a stable habitat for mosquito (7% positive overall) and Mesocyclops populations. If they remained wet, service manholes positive for mosquito immatures or Mesocyclops during summer/autumn had 96% and 85% chance, respectively, of being positive the following winter. Even allowing for the effect of drying, a mosquito-positive manhole had a 79% chance of remaining positive the following winter. In view of the importance of these sites as refuges from adverse ambient conditions, it is proposed that a winter control strategy using Mesocyclops presents a cost-effective control option to reduce the recolonization of surface sites when conditions become more suitable.
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national progress in dengue vector control in vietnam survey for Mesocyclops copepoda micronecta corixidae and fish as biological control agents
American Journal of Tropical Medicine and Hygiene, 2000Co-Authors: Vu Sinh Nam, Janet W. Reid, Maria Holynska, Nguyen Thi Yen, Brian H. KayAbstract:This paper describes the process of expanding a successful dengue control program in 3 provinces in northern Vietnam into a national one and demonstrates the presence of a rich, low-cost resource that could have similar applicability to other countries in the region. The cornerstone of the preventive strategy is larval control of Aedes aegypti (L.), the major vector, using predators such as copepods, Mesocyclops spp., aided by the corixid bug Micronecta quadristrigata Bredd, and fish in large water storage containers. From 1989 to 1998, 9 species of Mesocyclops (M. woutersi Van de Velde, M. aspericornis (Daday), M. ruttneri Kiefer, M. thermocyclopoides Harada, M. affinis Van de Velde, M. ogunnus Onabamiro, M. yenae Holynska, M. cf. pehpeiensis Hu, and M. dissimilis Defaye and Kawabata) were found in natural and artificial habitats in 26 provinces throughout Vietnam. The predatory capacities of 6 of these were evaluated in the laboratory. This indicated that daily consumption/killing averaged between 16 and 41 Ae. aegypti larvae per copepod. From detailed evaluations in 9 provinces, Mesocyclops spp. were surprisingly common in 8,413 artificial containers (concrete tanks, wells, ornamental ponds and in the south, large jars). Because of existing practices for washing and water transfer from ponds and lakes in Ha Tay and Ha Bac, Mesocyclops spp. already occurred in 60-100% of the water storage containers. When the relationship between the presence or absence of Mesocyclops and Aedes larvae in 5,111 containers was analyzed by the chi-square test, their distributions were significantly related, indicating control (odds ratio = 0.56). When 3,426 containers that did not contain Mesocyclops or fish were analyzed in relation to the distribution of Aedes larvae, those with Micronecta also had significantly less Aedes (odds ratio = 0.43). Therefore, this study demonstrates that there is an abundance of local Mesocyclops spp. in Vietnam that can be incorporated into specifically designed community-based control programs aided by Micronecta and fish.
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Mesocyclops of vietnam part i laboratory evaluation as biological agent for control of aedes aegypti
1999Co-Authors: Vu Sinh Nam, Gerald G. Marten, Brian H. Kay, Maria Holynska, Tran Van Tien, Trinh Quan Huan, Nguyen Thi Yen, Ron P Marchand, Janet W. ReidAbstract:Nine species of Mesocyclops reportedly present in Vietnam have been widely distributed; especially they are naturally present in certain drinking water containers such as concrete tanks, wells and jars. Mesocyclops can survive and develop in normal conditions and are good predators of first instars of Aedes aegypti larvae, the major vector of dengue fever/dengue haemorrhagic fever in Vietnam. In laboratory, a single Mesocyclops can kill the first-instar of Aedes aegypti larvae (on average) up to 41 by M. pehpeiensis, 37 by M. aspericornis, 31 by M. woutersi, 22 by M. thermocyclopoides, 21 by M. affinis and 16 by M. ogunnus during 24 hours. The studies suggest that Mesocyclops hold high potential as a biological agent for the control of Aedes aegypti.
Janet W. Reid - One of the best experts on this subject based on the ideXlab platform.
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new records of species of the genus Mesocyclops copepoda cyclopoida from cuba
Crustaceana, 2007Co-Authors: Rigoberto Fimia, Zulema Menendez, Janet W. ReidAbstract:We report new records of copepods of the genus Mesocyclops from Cuba. In the tropics, several species of Mesocyclops have shown promise as biological control agents for the larvae of disease-bearing mosquitoes. Mesocyclops aspericornis is considered pan-tropical, but has not previously been recorded here. Mesocyclops reidae , now found in a new locality, was previously reported from Cuba under the name M. ellipticus . We briefly review pertinent aspects of the taxonomic history, geographical distribution, and biology of these two species and of the two other members of the genus that are currently known to inhabit Cuba.
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an afro asian species of Mesocyclops copepoda cyclopoida in central america and mexico
Journal of Crustacean Biology, 2003Co-Authors: Martha Angelica Gutierrezaguirre, Janet W. Reid, Eduardo SuarezmoralesAbstract:Abstract The presence of populations of the Afro-Asian cyclopoid copepod crustacean Mesocyclops thermocyclopoides Harada, 1931, in southeastern Mexico and in Central America is recorded. This species was recently redescribed in detail from Old World specimens. Because of the rarity of cosmopolitan forms in Mesocyclops, neotropical records of this species were suspected to be undescribed taxa of a widespread species complex. However, it was possible, through an upgraded morphological analysis and taxonomic comparison, to confirm the occurrence of M. thermocyclopoides in the neotropics. The American specimens are described in full. In the Americas, this species seems to be distributed in Mexico and Central America only. This is the third or fourth Asian or African species of the genus that has apparently been introduced into the New World by human agency. The others are M. pehpeiensis, M. ogunnus, and M. aspericornis.
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national progress in dengue vector control in vietnam survey for Mesocyclops copepoda micronecta corixidae and fish as biological control agents
American Journal of Tropical Medicine and Hygiene, 2000Co-Authors: Vu Sinh Nam, Janet W. Reid, Maria Holynska, Nguyen Thi Yen, Brian H. KayAbstract:This paper describes the process of expanding a successful dengue control program in 3 provinces in northern Vietnam into a national one and demonstrates the presence of a rich, low-cost resource that could have similar applicability to other countries in the region. The cornerstone of the preventive strategy is larval control of Aedes aegypti (L.), the major vector, using predators such as copepods, Mesocyclops spp., aided by the corixid bug Micronecta quadristrigata Bredd, and fish in large water storage containers. From 1989 to 1998, 9 species of Mesocyclops (M. woutersi Van de Velde, M. aspericornis (Daday), M. ruttneri Kiefer, M. thermocyclopoides Harada, M. affinis Van de Velde, M. ogunnus Onabamiro, M. yenae Holynska, M. cf. pehpeiensis Hu, and M. dissimilis Defaye and Kawabata) were found in natural and artificial habitats in 26 provinces throughout Vietnam. The predatory capacities of 6 of these were evaluated in the laboratory. This indicated that daily consumption/killing averaged between 16 and 41 Ae. aegypti larvae per copepod. From detailed evaluations in 9 provinces, Mesocyclops spp. were surprisingly common in 8,413 artificial containers (concrete tanks, wells, ornamental ponds and in the south, large jars). Because of existing practices for washing and water transfer from ponds and lakes in Ha Tay and Ha Bac, Mesocyclops spp. already occurred in 60-100% of the water storage containers. When the relationship between the presence or absence of Mesocyclops and Aedes larvae in 5,111 containers was analyzed by the chi-square test, their distributions were significantly related, indicating control (odds ratio = 0.56). When 3,426 containers that did not contain Mesocyclops or fish were analyzed in relation to the distribution of Aedes larvae, those with Micronecta also had significantly less Aedes (odds ratio = 0.43). Therefore, this study demonstrates that there is an abundance of local Mesocyclops spp. in Vietnam that can be incorporated into specifically designed community-based control programs aided by Micronecta and fish.
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Mesocyclops of vietnam part i laboratory evaluation as biological agent for control of aedes aegypti
1999Co-Authors: Vu Sinh Nam, Gerald G. Marten, Brian H. Kay, Maria Holynska, Tran Van Tien, Trinh Quan Huan, Nguyen Thi Yen, Ron P Marchand, Janet W. ReidAbstract:Nine species of Mesocyclops reportedly present in Vietnam have been widely distributed; especially they are naturally present in certain drinking water containers such as concrete tanks, wells and jars. Mesocyclops can survive and develop in normal conditions and are good predators of first instars of Aedes aegypti larvae, the major vector of dengue fever/dengue haemorrhagic fever in Vietnam. In laboratory, a single Mesocyclops can kill the first-instar of Aedes aegypti larvae (on average) up to 41 by M. pehpeiensis, 37 by M. aspericornis, 31 by M. woutersi, 22 by M. thermocyclopoides, 21 by M. affinis and 16 by M. ogunnus during 24 hours. The studies suggest that Mesocyclops hold high potential as a biological agent for the control of Aedes aegypti.
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new hypogean cyclopoid copepods crustacea from the yucatan peninsula mexico
Contributions to Zoology, 1996Co-Authors: Frank Fiers, Janet W. Reid, Thomas M Iliffe, Eduardo SuarezmoralesAbstract:Four previously unknown hypogean species ofcyclopoid copepods were collected in cenotes and wells of the Yucatan Peninsula, Mexico. Diacyclops chakan sp. n. and D. puuc sp. n. differ from their congeners in combining 3-segmented swimming legs, 11-segmented antennules, and legs 1-4 endopodite segment 2 all with 2 setae. Species of Diacyclops rarely occur in tropical regions, and the Diacyclops described here are only the second and third species recorded from Mexico. The benthic D. puuc was found in the large underground reservoir of a cenote. Diacyclops chakan was encountered in such large open subterranean water basins, but more frequently and abundantly in wells. The two Mesocyclops species, M. chaci sp. n. and M. yutsil sp. n., most closely resemble their epigean benthic congener M. reidae Petkovski, but are modified by loss of some body ornament and attenuation of swimming legs and mouthparts. Mesocyclops chaci sp. n. occupies crevicular spaces (wells and small caverns). The second species, M. yutsil sp. n., with more pronounced attenuation of legs, has a planktonic life in large subterranean water volumes. The extremely attenuated appendages of both species distinguish them from all other Mesocyclops, and resemble those of the hypogean Kieferiella delamarei Lescher-Moutoue. These three species are considered as a species-flock which have radiated as specialists within a highly dynamic geomorphological environment.
Maria Holynska - One of the best experts on this subject based on the ideXlab platform.
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Mesocyclops and thermocyclops copepoda cyclopidae in the major visayas islands central philippines
Crustaceana, 2016Co-Authors: Erica Silk Dela P Paz, Maria Holynska, Rey Donne S PapaAbstract:Our knowledge of the freshwater cyclopid copepods of the Visayas Islands remains poor as compared to other terrestrial and aquatic fauna. This study focuses on two genera, Mesocyclops and Thermocyclops , which are common components of lake plankton communities. This study included specimens collected from 59 sampling sites found in major islands (Panay, Negros, Cebu, Bohol, Leyte and Samar) and a small island (Pacijan) in the Visayas region. Four species of Mesocyclops and three species of Thermocyclops were identified. This includes the first record of Mesocyclops woutersi in the Philippines, which was so far unknown from insular SE Asia. The endemic Mesocyclops microlasius , previously reported from Luzon Island, was also found in Lake Danao (Pacijan Island). An identification key to Philippine species of Mesocyclops and Thermocyclops is herein provided. Geographic distribution and possible causes of the low number of species observed and their implications for further faunal studies are also discussed.
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current invasions of asian cyclopid species copepoda cyclopidae in crimea with taxonomical and zoogeographical remarks on the hypersaline and freshwater fauna
Annales Zoologici, 2014Co-Authors: Elena V Anufriieva, Maria Holynska, Nickolai V ShadrinAbstract:Abstract. The Crimean Peninsula holds a large number of hypersaline water bodies. Our studies focused on these poorly investigated habitats, and included few brackish and freshwater ponds. Seventeen species were identified, of which only 4(5) were collected from hypersaline waters sometimes with extremely high salinities (Acanthocyclops sp. copepodid, 210 ppt; Eucyclops sp. copepodid, 150 ppt; Diacyclops bisetosus and Cyclops furcifer, 140–150 ppt). We also report on the occurrence of three alien thermophilic species (Eucyclops roseus Ishida, 1997, Mesocyclops isabellae Dussart et Fernando, 1988, and Mesocyclops pehpeiensis Hu, 1943) from the brackish and fresh waters of Crimea. Morphological descriptions, illustrations of the diagnostic characters and comments on relevant taxonomic issues are supplemented with discussion of the putative ways of dispersal of the alien copepods to Crimea. We provisionally reinstate Eucyclops roseus, regarded by others as a subspecies of E. agiloides (G. O. Sars, 1909), and...
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Mesocyclops crustacea copepoda cyclopidae in the south pacific islands
Zoologischer Anzeiger – A Journal of Comparative Zoology, 2012Co-Authors: Maria Holynska, Fabio StochAbstract:Abstract Based mainly on recently collected material, we discuss the taxonomy and zoogeography of a (sub)tropical genus, Mesocyclops, in the South Pacific. A new species, Mesocyclops roberti sp. nov. is described from Fiji and the Wallis Islands. New data on the geographic distribution and morphology are reported for Mesocyclops medialis, Mesocyclops woutersi and Mesocyclops aspericornis. Phylogenetic reconstructions coding the intraspecifically variable characters by three different methods (unordered, unscaled and scaled coding) support close relationship of M. roberti with two Australian species (Mesocyclops brooksi and Mesocyclops notius). Both the “unordered” and “scaled” analyses show monophyly of a group composed of Australian (Mesocyclops australiensis, M. brooksi, M. notius, and Mesocyclops pubiventris) and South Pacific (M. medialis and M. roberti sp. nov.) taxa. None of the analyses supports a sister relationship of M. roberti with M. medialis (New Caledonia, Vanuatu), the only other species restricted to South Pacific, which suggests that Mesocyclops invaded the South Pacific from Australia at least twice. The sister relationship of the Australian-South Pacific clade remains unresolved, yet all reconstructions suggest a link with Asian Mesocyclops sp.
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phylogeny of the freshwater copepod Mesocyclops crustacea cyclopidae based on combined molecular and morphological data with notes on biogeography
Molecular Phylogenetics and Evolution, 2010Co-Authors: Grace A. Wyngaard, Maria Holynska, James A SchulteAbstract:We combined molecular and morphological characters in a copepod taxon for which obtaining a sufficiently high number of characters that evolve at different rates is a challenge. Few molecular markers are known to resolve evolutionary relationships in the copepods, and thus there is potential for morphology to contribute substantially to phylogenetic reconstruction. We used a morphology based tree of the entire Mesocyclops genus to guide our taxon sampling of 10 species for molecular and combined analyses. Morphology including polymorphic characters, 18S rDNA, and ITS2 sequences were analyzed using parsimony, ML, and Bayesian methods. Strong similarities among topologies were observed regardless of the character type or algorithm, with higher levels of support obtained in combined data analyses. In combined analyses Old World species formed a monophyletic group and New World species formed a paraphyletic group in this freshwater, predominantly (sub)tropical genus. Mesocyclops darwini was the single taxon whose relationships showed conflict among the previous reconstructions using only morphological characters and the tree inferred from the combined data set. Support for these alternative positions of M. darwini were compared using constraint tests, with the result supporting monophyly of Old World taxa.
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a new oriental species of Mesocyclops copepoda cyclopidae
Hydrobiologia, 2000Co-Authors: Maria Holynska, Vu Sinh NamAbstract:Mesocyclops ferjemurami sp. nov. is described from Central Vietnam, North India and Sri Lanka. It differs from all congeners in having a unique spinule ornamentation on the caudal surface of the antennary basipodite: the `leuckarti-type' spinule pattern is supplemented with a group of spinules at the height of implantation of the medial setae, and proximal to this group a triangular spinule field occurs, the longest side of which runs more or less parallel to the oblique row of tiny spinules starting at distal half of the medial rim. It is suggested that Mesocyclops ferjemurami is closely related to Mesocyclops pehpeiensis Hu, 1943 and Mesocyclops papuensis Van de Velde, 1987.
Vu Sinh Nam - One of the best experts on this subject based on the ideXlab platform.
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control of aedes vectors of dengue in three provinces of vietnam by use of Mesocyclops copepoda and community based methods validated by entomologic clinical and serological surveillance
American Journal of Tropical Medicine and Hygiene, 2002Co-Authors: Brian H. Kay, Vu Sinh Nam, Tran Van Tien, Nguyen Thi Yen, Tran Vu Phong, Vu Thi Bich Diep, Truong Uyen Ninh, Ahmet Bektas, John AaskovAbstract:We describe remarkable success in controlling dengue vectors, Aedes aegypti (L.) and Aedes albopictus (Skuse), in 6 communes with 11,675 households and 49,647 people in the northern provinces of Haiphong, Hung Yen, and Nam Dinh in Vietnam. The communes were selected for high-frequency use of large outdoor concrete tanks and wells. These were found to be the source of 49.6-98.4% of Ae. aegypti larvae, which were amenable to treatment with local Mesocyclops, mainly M. woutersi Van der Velde, M. aspericornis (Daday) and M. thermocyclopoides Harada. Knowledge, attitude, and practice surveys were performed to determine whether the communities viewed dengue and dengue hemorrhagic fever as a serious health threat; to determine their knowledge of the etiology, attitudes, and practices regarding control methods including Mesocyclops; and to determine their receptivity to various information methods. On the basis of the knowledge, attitude, and practice data, the community-based dengue control program comprised a system of local leaders, health volunteer teachers, and schoolchildren, supported by health professionals. Recycling of discards for economic gain was enhanced, where appropriate, and this, plus 37 clean-up campaigns, removed small containers unsuitable for Mesocyclops treatment. A previously successful eradication at Phan Boi village (Hung Yen province) was extended to 7 other villages forming Di Su commune (1,750 households) in the current study. Complete control was also achieved in Nghia Hiep (Hung Yen province) and in Xuan Phong (Nam Dinh province); control efficacy was > or = 99.7% in the other 3 communes (Lac Vien in Haiphong, Nghia Dong, and Xuan Kien in Nam Dinh). Although tanks and wells were the key container types of Ae. aegypti productivity, discarded materials were the source of 51% of the standing crop of Ae. albopictus. Aedes albopictus larvae were eliminated from the 3 Nam Dinh communes, and 86-98% control was achieved in the other 3 communes. Variable dengue attack rates made the clinical and serological comparison of control and untreated communes problematic, but these data indicate that clinical surveillance by itself is inadequate to monitor dengue transmission.
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a new oriental species of Mesocyclops copepoda cyclopidae
Hydrobiologia, 2000Co-Authors: Maria Holynska, Vu Sinh NamAbstract:Mesocyclops ferjemurami sp. nov. is described from Central Vietnam, North India and Sri Lanka. It differs from all congeners in having a unique spinule ornamentation on the caudal surface of the antennary basipodite: the `leuckarti-type' spinule pattern is supplemented with a group of spinules at the height of implantation of the medial setae, and proximal to this group a triangular spinule field occurs, the longest side of which runs more or less parallel to the oblique row of tiny spinules starting at distal half of the medial rim. It is suggested that Mesocyclops ferjemurami is closely related to Mesocyclops pehpeiensis Hu, 1943 and Mesocyclops papuensis Van de Velde, 1987.
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national progress in dengue vector control in vietnam survey for Mesocyclops copepoda micronecta corixidae and fish as biological control agents
American Journal of Tropical Medicine and Hygiene, 2000Co-Authors: Vu Sinh Nam, Janet W. Reid, Maria Holynska, Nguyen Thi Yen, Brian H. KayAbstract:This paper describes the process of expanding a successful dengue control program in 3 provinces in northern Vietnam into a national one and demonstrates the presence of a rich, low-cost resource that could have similar applicability to other countries in the region. The cornerstone of the preventive strategy is larval control of Aedes aegypti (L.), the major vector, using predators such as copepods, Mesocyclops spp., aided by the corixid bug Micronecta quadristrigata Bredd, and fish in large water storage containers. From 1989 to 1998, 9 species of Mesocyclops (M. woutersi Van de Velde, M. aspericornis (Daday), M. ruttneri Kiefer, M. thermocyclopoides Harada, M. affinis Van de Velde, M. ogunnus Onabamiro, M. yenae Holynska, M. cf. pehpeiensis Hu, and M. dissimilis Defaye and Kawabata) were found in natural and artificial habitats in 26 provinces throughout Vietnam. The predatory capacities of 6 of these were evaluated in the laboratory. This indicated that daily consumption/killing averaged between 16 and 41 Ae. aegypti larvae per copepod. From detailed evaluations in 9 provinces, Mesocyclops spp. were surprisingly common in 8,413 artificial containers (concrete tanks, wells, ornamental ponds and in the south, large jars). Because of existing practices for washing and water transfer from ponds and lakes in Ha Tay and Ha Bac, Mesocyclops spp. already occurred in 60-100% of the water storage containers. When the relationship between the presence or absence of Mesocyclops and Aedes larvae in 5,111 containers was analyzed by the chi-square test, their distributions were significantly related, indicating control (odds ratio = 0.56). When 3,426 containers that did not contain Mesocyclops or fish were analyzed in relation to the distribution of Aedes larvae, those with Micronecta also had significantly less Aedes (odds ratio = 0.43). Therefore, this study demonstrates that there is an abundance of local Mesocyclops spp. in Vietnam that can be incorporated into specifically designed community-based control programs aided by Micronecta and fish.
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Mesocyclops of vietnam part i laboratory evaluation as biological agent for control of aedes aegypti
1999Co-Authors: Vu Sinh Nam, Gerald G. Marten, Brian H. Kay, Maria Holynska, Tran Van Tien, Trinh Quan Huan, Nguyen Thi Yen, Ron P Marchand, Janet W. ReidAbstract:Nine species of Mesocyclops reportedly present in Vietnam have been widely distributed; especially they are naturally present in certain drinking water containers such as concrete tanks, wells and jars. Mesocyclops can survive and develop in normal conditions and are good predators of first instars of Aedes aegypti larvae, the major vector of dengue fever/dengue haemorrhagic fever in Vietnam. In laboratory, a single Mesocyclops can kill the first-instar of Aedes aegypti larvae (on average) up to 41 by M. pehpeiensis, 37 by M. aspericornis, 31 by M. woutersi, 22 by M. thermocyclopoides, 21 by M. affinis and 16 by M. ogunnus during 24 hours. The studies suggest that Mesocyclops hold high potential as a biological agent for the control of Aedes aegypti.
Takayuki Hanazato - One of the best experts on this subject based on the ideXlab platform.
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Different Predation Impacts of Two Cyclopoid Species on a Small-sized Zooplankton Community: An Experimental Analysis with Mesocosms
Hydrobiologia, 2006Co-Authors: Takamaru Nagata, Takayuki HanazatoAbstract:We used mesocosms to analyze predation impacts on the prey populations and prey community structures by two cyclopoid copepod species, the larger Mesocyclops pehpeiensis and the smaller Thermocyclops taihokuensis, who coexist with small-sized herbivorous zooplankton species in a fish-abundant lake. The overall predation impact on the prey populations was stronger for Mesocyclops than for Thermocyclops. Mesocyclops had a strong and less selective impact on the rotifer community but a selective impact on the crustaceans. In contrast, Thermocyclops had a selective predation impact on rotifers but a weak and less selective impact on the crustacean community. As a result, the former predator reduced the diversity of the crustacean community but not the rotifer community, while the latter had an opposite impact on the diversities of the two communities. It has been suggested that fish induce development of a zooplankton community dominated by the small-sized zooplankton species in fish-abundant lakes. Our results demonstrated that cyclopoid copepods altered species composition and diversity of the small-sized zooplankton community in such lakes. Thus, the results have given an important suggestion on the role of the invertebrate predator cyclopoid copepods, which often coexist with fish, that they determine population dynamics and community structures of small-sized zooplankton in fish-abundant lakes.
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the predacious cladoceran leptodora kindtii as a prey for the cyclopoid copepod Mesocyclops sp laboratory observations of predator prey interaction
Journal of Freshwater Ecology, 2005Co-Authors: Kwang-hyeon Chang, Takayuki HanazatoAbstract:ABSTRACT We observed the behavior of the cyclopoid copepod Mesocyclops sp. as it fed on the cladoceran Leptodora kindtii in the laboratory. The feeding efficiency (capture and ingestion successes) of Mesocyclops sp. was high for smaller L. kindtii (<2.5 mm in body size) but low for larger ones. Mesocyclops sp. ingested small L. kindtii whole, but often consumed parts of larger L. kindtii. The handling time increased as the L. kindtii body size increased, except when Mesocyclops sp. consumed only the second antennae. These laboratory observations suggest that Mesocyclops sp. may be a natural predator of small L. kindtii.
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diel vertical migrations of invertebrate predators leptodora kindtii thermocyclops taihokuensis and Mesocyclops sp in a shallow eutrophic lake
Hydrobiologia, 2004Co-Authors: Kwang-hyeon Chang, Takayuki HanazatoAbstract:We studied vertical distribution patterns of three invertebrate predators – Leptodora kindtii, Mesocyclopssp., and Thermocyclops taihokuensis– in a shallow eutrophic lake, Lake Suwa , Japan. From June to October in 2000 and 2001, we collected samples in the lake center in order to examine the vertical distribution patterns and the densities of the predators in the water column during the day (0900) and at night (2330). We also examined phototactic behavior of Leptodora in the laboratory. The three invertebrate predators showed clear migration patterns. Leptodora and Thermocyclops displayed a typical migration, avoiding the surface and maintaining a high abundance in deeper water during the day, and being distributed uniformly during the night. Mesocyclops, on the other hand, showed no clear vertical distribution pattern in the water column. However, Mesocyclops showed higher densities in the water column during the night than during the day. It suggests that they stayed just above the bottom during the day and migrated upward during the night. Leptodora also showed such a density difference between day and night. In the laboratory, Leptodora showed strong negative phototactic behavior. The observed density changes between day and night in Leptodora and Mesocyclops suggests the possible underestimation of their population density by usual sampling methods, and thus the impact of predation on populations of prey zooplankton species may also be underestimated in shallow water bodies.
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Vulnerability of cladoceran species to predation by the copepod Mesocyclops leuckarti: laboratory observations on the behavioural interactions between predator and prey
Freshwater Biology, 2003Co-Authors: Kwang-hyeon Chang, Takayuki HanazatoAbstract:SUMMARY 1. We analysed the vulnerability of a number of cladoceran species (Bosmina longirostris, B. fatalis, Diaphanosoma brachyurum, Ceriodaphnia reticulata, Daphnia ambigua and D. pulex) to predation by Mesocyclops leuckarti in the laboratory. 2. The prey species represented a wide range of body size, morphology, and swimming behaviour. To compare vulnerability, we measured the efficiency of capture and ingestion of each prey species by Mesocyclops. We also measured the rate at which prey were damaged in attacks by Mesocyclops. 3. Mesocyclops preyed effectively on Diaphanosoma and small juvenile Ceriodaphnia but not on Bosmina or Daphnia. Observations suggested that various defence mechanisms, including protruding structures and swimming behaviour and speed, are important in determining prey vulnerability. 4. The body size of Daphnia and Ceriodaphnia seems to be important, because larger animals were better able to escape Mesocyclops attacks. Attacks by Mesocyclops often caused fatal damage, however, even to large Daphnia.
