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1

Melanoides tuberculata as intermediate host of Philophthalmus gralli in Brazil.  

PubMed

Melanoides tuberculata that naturally harbored trematode larvae were collected at the Pampulha dam, Belo Horizonte (Minas Gerais, Brazil), during malacological surveys conducted from 2006 to 2010. From 7,164 specimens of M. tuberculata collected, 25 (0.35%) were infected by cercariae, which have been morphologically characterized as belonging to the Megalurous group, genus Philophthalmus. Excysted metacercariae were used for successful experimental infection of Gallus gallus domesticus, and adult parasites recovered from the nictitating membranes of chickens were identified as Philophthalmus gralli. This is the first report of P. gralli in M. tuberculata in Brazil. PMID:21225216

Pinto, Hudson Alves; Melo, Alan Lane de

2

The invasive snail Melanoides tuberculata in Argentina and Paraguay  

Microsoft Academic Search

This article reviews the spread and current distribution of the invasive snail Melanoides tuberculata in Argentina and Paraguay based on data from specimens deposited in museums, published reports and field collections. Field collections were made between April 1999 and May 2010. Snails were searched for using different collecting methods in a variety of habitats. Specimens were identified according to a

Juana G. Peso; Diego C. Pérez; Roberto E. Vogler

2011-01-01

3

Morphological and Genetic Analyses of Melanoides tuberculata Populations in Egypt  

Microsoft Academic Search

2 Abstract: Melanoides tuberculata snail (Thiaridae) gained recently extra medical and or veterinary importance since several new types of cercariae were procured from it in Egypt. Therefore the morphological and genetic analyses of its populations in this country were studied. Thousands of snails were collected from various localities and the chonchological data of them were gathered. Five morphs were distinguished

Fouad Yousif; Abdalla Ibrahim; Setaita Sleem; Samia EL Bardicy; Magda Ayoub

4

POPULATION DYNAMICS OF FRESHWATER MOLLUSCS (GASTROPOD: MELANOIDES TUBERCULATA) IN CROCKER RANGE PARK, SABAH  

Microsoft Academic Search

A study of population dynamic of freshwater molluscs (gastropod:Melanoides tuberculata) at Crocker Range Park was conducted at two sites during 15 to 24 October 1999. Only one species of fresh water gastropod belonging to family Thiaridae was found and identified. Melanoides tuberculata dominated the fast flowing upper and middle stream. They were found in abundance within their standard length size

Z. Supian; A. M. Ikhwanuddin

5

Toxicity of metals to a freshwater snail, Melanoides tuberculata.  

PubMed

Adult freshwater snails Melanoides tuberculata (Gastropod, Thiaridae) were exposed for a four-day period in laboratory conditions to a range of copper (Cu), cadmium (Cd), zinc (Zn), lead (Pb), nickel (Ni), iron (Fe), aluminium (Al), and manganese (Mn) concentrations. Mortality was assessed and median lethal times (LT??) and concentrations (LC??) were calculated. LT?? and LC?? increased with the decrease in mean exposure concentrations and times, respectively, for all metals. The LC(50) values for the 96-hour exposures to Cu, Cd, Zn, Pb, Ni, Fe, Al, and Mn were 0.14, 1.49, 3.90, 6.82, 8.46, 8.49, 68.23, and 45.59?mg?L?¹, respectively. Cu was the most toxic metal to M. tuberculata, followed by Cd, Zn, Pb, Ni, Fe, Mn, and Al (Cu > Cd > Zn > Pb > Ni > Fe > Mn > Al). Metals bioconcentration in M. tuberculata increases with exposure to increasing concentrations and Cu has the highest accumulation (concentration factor) in the soft tissues. A comparison of LC?? values for metals for this species with those for other freshwater gastropods reveals that M. tuberculata is equally sensitive to metals. PMID:22666089

Shuhaimi-Othman, M; Nur-Amalina, R; Nadzifah, Y

2012-04-24

6

Toxicity of Metals to a Freshwater Snail, Melanoides tuberculata  

PubMed Central

Adult freshwater snails Melanoides tuberculata (Gastropod, Thiaridae) were exposed for a four-day period in laboratory conditions to a range of copper (Cu), cadmium (Cd), zinc (Zn), lead (Pb), nickel (Ni), iron (Fe), aluminium (Al), and manganese (Mn) concentrations. Mortality was assessed and median lethal times (LT50) and concentrations (LC50) were calculated. LT50 and LC50 increased with the decrease in mean exposure concentrations and times, respectively, for all metals. The LC50 values for the 96-hour exposures to Cu, Cd, Zn, Pb, Ni, Fe, Al, and Mn were 0.14, 1.49, 3.90, 6.82, 8.46, 8.49, 68.23, and 45.59?mg?L?1, respectively. Cu was the most toxic metal to M. tuberculata, followed by Cd, Zn, Pb, Ni, Fe, Mn, and Al (Cu > Cd > Zn > Pb > Ni > Fe > Mn > Al). Metals bioconcentration in M. tuberculata increases with exposure to increasing concentrations and Cu has the highest accumulation (concentration factor) in the soft tissues. A comparison of LC50 values for metals for this species with those for other freshwater gastropods reveals that M. tuberculata is equally sensitive to metals.

Shuhaimi-Othman, M.; Nur-Amalina, R.; Nadzifah, Y.

2012-01-01

7

[The discovery of Melanoides tuberculata as the first intermediate host of Echinochasmus japonicus].  

PubMed

This paper reports on the discovery of cercariae which are similar to those of Echinotomatidae in Melanoides tuberculata in Yunxiao and Zhaoan Counties of Fujian. Encysted metacercariae were found in the gills of fresh-water fish after experimental infection with the cercariae for 3 to 4 hours. Adult worms identified as Echinochasmus japonicus were obtained from Mesocricetus auratus and dove after infection with the metacercariae. Melanoides tuberculata was recorded for the first time as the first intermediate host of E. japonicus and its natural infection rate was found to be 1.1%. The morphological characteristics of the cercaria are described. PMID:2766498

Cheng, Y Z; Fang, Y Y

1989-01-01

8

Melanoides tuberculata (Mollusca: Thiaridae) as an intermediate host of Centrocestus formosanus (Trematoda: Heterophyidae) in Brazil.  

PubMed

Pleurolophocercous cercariae emerged from naturally infected Melanoides tuberculata from Minas Gerais State, Brazil, were used to perform experimental infection of laboratory-reared Poecilia reticulata. Mature metacercariae were obtained from the gills of fishes and force-fed to Mus musculus. The adult parasites which recovered from small intestines of mice were identified as Centrocestus formosanus. This is the first report of M. tuberculata as intermediate host of this heterophyid in Brazil. PMID:21748229

Pinto, Hudson Alves; de Melo, Alan Lane

9

The Introduction of an Invasive Snail (Melanoides tuberculata) to Spring Ecosystems of the Bonneville Basin, Utah  

Microsoft Academic Search

Melanoides tuberculata is an invasive tropical prosobranch snail that was first introduced to the Bonneville Basin, Utah, sometime in the 1960's. During 2001 and 2002 we searched 276 sites\\/habitat types (limnocrenes, rheocrenes, and helocrenes) in 124 springs, nested in 14 valleys distributed throughout the Bonneville Basin and found this snail abundant in 17 of the 124 springs and occurring in

Russell B. Rader; Mark C. Belk; M. Jane Keleher

2003-01-01

10

Apparent competition through facilitation between Melanoides tuberculata and Biomphalaria glabrata and the control of schistosomiasis  

Microsoft Academic Search

Interactions between two species that result in reduced growth rates for both and extinction of one of the species are generally considered cases of asymmetric interspecific competition. Exploitative or interference competition is the usual mechanism invoked. Here we describe another mechanism producing the same result, named apparent competition through facilitation (ACF), observed between Melanoides tuberculata and Biomphalaria glabrata popu- lations.

Alexandre Giovanelli; Marcus Vinicius Vieira; Cesar Luiz Pinto Ayres Coelho da Silva

2003-01-01

11

Did life history evolve in response to parasites in invasive populations of Melanoides tuberculata?  

Microsoft Academic Search

Enemy release and rapid evolution are often assumed to promote biological invasions. In the parthenogenetic snail Melanoides tuberculata, one invasive strain (MAD) was assumed to benefit from enemy release until a heavily parasitized population was found in Colombia (in the area of introduction). This population is prosperous despite important losses in the reproductive potential due to a high prevalence of

Juan Sebastián Escobar; Ana Cristina Correa; Patrice David

2009-01-01

12

Influence of intracellular toxin concentrations on cylindrospermopsin bioaccumulation in a freshwater gastropod ( Melanoides tuberculata)  

Microsoft Academic Search

Scant information is available regarding the bioaccumulation of cylindrospermopsin (CYN) in aquatic organisms, particularly in invertebrates. This study examined toxin bioconcentration and bioaccumulation in the aquatic snail, Melanoides tuberculata, following exposure to freeze–thawed whole cell extracts and a live Cylindrospermopsis raciborskii culture containing CYN. Both bioconcentration and bioaccumulation were evident, but exposure to toxin in the freeze–thawed solutions resulted in

S. H. White; L. J. Duivenvoorden; L. D. Fabbro; G. K. Eaglesham

2006-01-01

13

Sublethal responses in Melanoides tuberculata following exposure to Cylindrospermopsis raciborskii containing cylindrospermopsin  

Microsoft Academic Search

Sublethal effects in the aquatic snail Melanoides tuberculata were examined during exposure to whole cell extracts of Cylindrospermopsis raciborskii and live C. raciborskii cultures, containing varying concentrations of algal cells, cellular debris, and the blue-green algal toxin, cylindrospermopsin (CYN). Exposure to whole cell extracts or live algal cultures did not result in significant changes in adult snail behaviour or relative

S. H. W. Kinnear; L. J. Duivenvoorden; L. D. Fabbro

2007-01-01

14

Possible competitive displacement of planorbids by Melanoides tuberculata in Minas Gerais, Brazil.  

PubMed

Several species of snails, including Pomacea haustrum, Marisa cornuarietis and Helisoma duryi, have been identified as probable competitors and/or predators of planorbid intermediate hosts of Schistosoma. During the last few years, studies carried out in the Caribbean region have shown reductions and even disappearances of populations of Biomphalaria glabrata and B. straminea in breeding places where the snail Melanoides tuberculata was introduced. Observations made over a period of 10 years in two lakes close to Belo Horizonte, MG, showed that there were marked reductions in autochthonous populations of B. glabrata and B. straminea after the arrival of M. tuberculata, both Biomphalaria species disappearing completely after eight years. PMID:11586446

Guimarães, C T; Souza, C P; Soares Dd

2001-01-01

15

The potential significance to human health associated with the establishment of the snail Melanoides tuberculata in New Zealand  

Microsoft Academic Search

The thiarid Melanoides tuberculata (Müller, 1774) (Gastropoda: Prosobranchia: Thiaridae) is considered to be invasive and have become established in numerous countries outside its native range. This species was discovered in the wild for the first time in New Zealand in 2001, when a population was found in a geothermally warmed stream at Golden Springs near Taupo. M. tuberculata is of

José G B Derraik

16

Life cycle and identification of an eyefluke from Israel transmitted by Melanoides tuberculata (Müller, 1774).  

PubMed

A philophthalmid species from Israel using the freshwater snail Melanoides tuberculata as intermediate host was studied. The biological and morphological characteristics of all developmental stages of the life cycle of this philophthalmid were described, and compared to those of Philophthalmus lucipetus Rudolphi, 1819 from Israel, Philophthalmus gralli Mathis and Leger, 1910 from Jordan, Philophthalmus palpebrarum Looss, 1899, Philophthalmus nocturnus Looss, 1907, Cercaria distomatosa Looss 1896 from Egypt, and Philophthalmus lucknowensis Baugh, 1962 from India. The possible identity with 1 of these species is discussed. On the basis of comparative analysis of the data for all parasite stages in the life cycle, geographical distribution, snail hosts, and snail host specificity, we propose to designate the Israeli Melanoides tuberculata-transmitted eye fluke to Philophthalmus distomatosa n. comb. (Looss, 1896), (Digenea: Philophthalmidae). PMID:10958455

Radev, V; Kanev, I; Gold, D

2000-08-01

17

Density and variability of dinucleotide microsatellites in the parthenogenetic polyploid snail Melanoides tuberculata.  

PubMed

Characterization of microsatellites in the parthenogenetic polyploid snail Melanoides tuberculata revealed an unusual high density of dinucleotide repeats. Multiple banding patterns were obtained at these loci, and interpreted as a consequence of polyploidy. Microsatellite variability was low within, but high between, shell morphotypes. Genotypes were wholly transmitted from mothers to offspring. These results suggest that reproduction is strictly apomictic, and that shell morphotypes are genetic clones. PMID:9734077

Samadi, S; Artiguebielle, E; Estoup, A; Pointier, J P; Silvain, J F; Heller, J; Cariou, M L; Jarne, P

1998-09-01

18

Melanoides tuberculata (Mollusca: Thiaridae) harboring renicolid cercariae (Trematoda: Renicolidae) in Brazil.  

PubMed

Melanoides tuberculata , naturally infected by gymnocephalous cercariae, were found in aquatic collections from Belo Horizonte, Minas Gerais, Brazil. After morphological characterization, larvae were used for experimental infection of Poecilia reticulata. Metacercariae were obtained from the liver of these fish, which were also found to be naturally infected in the same locality. The morphology and biology of the developmental stages of trematodes we obtained were characteristic of Renicola sp. This is the first record of renicolid cercariae and metacercariae in Brazil. PMID:22288437

Pinto, H A; Melo, A L

2012-01-30

19

Influence of intracellular toxin concentrations on cylindrospermopsin bioaccumulation in a freshwater gastropod (Melanoides tuberculata).  

PubMed

Scant information is available regarding the bioaccumulation of cylindrospermopsin (CYN) in aquatic organisms, particularly in invertebrates. This study examined toxin bioconcentration and bioaccumulation in the aquatic snail, Melanoides tuberculata, following exposure to freeze-thawed whole cell extracts and a live Cylindrospermopsis raciborskii culture containing CYN. Both bioconcentration and bioaccumulation were evident, but exposure to toxin in the freeze-thawed solutions resulted in minor tissue contamination compared with that resulting from live C. raciborskii exposure. Thus, whilst CYN uptake resulted from both extracellular and intracellular exposures, the availability of intracellular toxin was critical in affecting tissue CYN values. M. tuberculata did not bioconcentrate CYN into the shell. Bioaccumulation of the analog deoxy-CYN was also recorded. Knowledge of intracellular toxin concentrations may be critical in evaluating the bioaccumulation, ecological and human health risks associated with contaminated systems. PMID:16564064

White, S H; Duivenvoorden, L J; Fabbro, L D; Eaglesham, G K

2006-03-24

20

First record of a wild population of the tropical snail Melanoides tuberculata in New Zealand natural waters  

Microsoft Academic Search

The thiarid snail Melanoides tuberculata (Müller, 1774), native to the Middle East and East Africa, is recorded from the wild in New Zealand for the first time from a geothermally influenced stream at Golden Springs, near Taupo. Introduction was most likely the result of one or more releases from tropical aquaria, although the timing of release is uncertain. Specimens were

I. C. Duggan

2002-01-01

21

VARIATION OF SHELL SHAPE IN THE CLONAL SNAIL MELANOIDES TUBERCULATA AND ITS CONSEQUENCES FOR THE INTERPRETATION OF FOSSIL SERIES  

Microsoft Academic Search

Interpreting paleontological data is difficult because the genetic nature of observed morphological variation is generally unknown. Indeed, it is hardly possible to distinguish among several sources of morphological variation including phenotypic plasticity, sexual dimorphism, within-species genetic variation or differences among species. This can be addressed using fossil organisms with recent representatives. The freshwater snail Melanoides tuberculata ranks in this category.

Sarah Samadi; Patrice David; Philippe Jarne

2000-01-01

22

Hybridization and invasiveness in the freshwater snail Melanoides tuberculata: hybrid vigour is more important than increase in genetic variance  

Microsoft Academic Search

Many invasive taxa are hybrids, but how hybridization boosts the invasive process remains poorly known. We address this question in the clonal freshwater snail Melanoides tuberculata from Martinique, using three parental and two hybrid lines. We combine an extensive field survey (1990-2003) and a quantitative genetic experiment to show that hybrid lines have outcompeted their parents in natural habitats, and

B. FACON; P. JARNE; J. P. POINTIER; P. DAVID

2005-01-01

23

The influence of chemical cues and conspecific density on the temperature selection of a freshwater snail ( Melanoides tuberculata)  

Microsoft Academic Search

1. The effects of predation risk (via chemical cues) and conspecific density on temperature selection of the freshwater snail Melanoides tuberculata were assessed within a circular thermal gradient.2. Chemical cues from crushed conspecifics elicited the strongest avoidance response of snails in isothermal conditions.3. Following the addition of chemical cues to the thermal gradient, snails became more active and did not

Gary W. Gerald; Lawrence C. Spezzano

2005-01-01

24

Apparent competition through facilitation between Melanoides tuberculata and Biomphalaria glabrata and the control of schistosomiasis.  

PubMed

Interactions between two species that result in reduced growth rates for both and extinction of one of the species are generally considered cases of asymmetric interspecific competition. Exploitative or interference competition is the usual mechanism invoked. Here we describe another mechanism producing the same result, named apparent competition through facilitation (ACF), observed between Melanoides tuberculata and Biomphalaria glabrata populations. The superior competitor actually gives some benefit to the other species, whose population becomes unstable with progressively increasing oscillations, leading to extinction. A model of ACF using difference equations suggests initial dynamics distinct from traditional interspecific competition. The dynamics of two freshwater snails in the field and in laboratory experiments suggest ACF, and these relations should be considered in studies of schistosomiasis control. ACF could occur in natural populations, but might have gone undetected because the final result is similar to traditional interspecific competition. PMID:12886429

Giovanelli, Alexandre; Vieira, Marcus Vinicius; da Silva, Cesar Luiz Pinto Ayres Coelho

2003-07-18

25

Ovoviviparity and the structure of the brood pouch in Melanoides tuberculata (Gastropoda: Prosobranchia: Thiaridae).  

PubMed

The freshwater gastropod Melanoides tuberculata broods its young in a pouch located in the anterodorsal region of the head-foot. The wall of the brood pouch is composed of smooth muscle surrounded by connective tissue. The lumen of the brood pouch is incompletely partitioned by trabeculae, formed by extensions or folds in the chamber wall that are composed of smooth muscle, connective tissue, nonciliated squamous epithelial cells, and some storage cells containing lipid and glycogen. The lumen of the chamber also contains a few cells with storage products. The general absence of secretory cells suggests that embryos derive little nutrition from the mother, and therefore embryonic development is probably ovoviviparous. Embryos in various stages of development were found within brood pouches, with later stage embryos varying in size. There was a negative relationship between embryo size and number of embryos in the brood pouch. PMID:15688449

Ben-Ami, Frida; Hodgson, Alan N

2005-03-01

26

The potential significance to human health associated with the establishment of the snail Melanoides tuberculata in New Zealand.  

PubMed

The thiarid Melanoides tuberculata (Müller, 1774) (Gastropoda: Prosobranchia: Thiaridae) is considered to be invasive and have become established in numerous countries outside its native range. This species was discovered in the wild for the first time in New Zealand in 2001, when a population was found in a geothermally warmed stream at Golden Springs near Taupo. M. tuberculata is of human health significance as the intermediate host of a number of trematode parasites. Uncertainties hinder an accurate assessment of the risks to human health occasioned by this species in New Zealand, but it is theoretically possible that a number of parasites could become established in this country in association with M. tuberculata. However, their distribution would be potentially limited, as M. tuberculata is unlikely to find suitable habitats in New Zealand outside certain geothermally warmed water habitats. PMID:18791625

Derraik, José G B

2008-08-22

27

Palaeoclimatic implications of isotopic data from modern and early Holocene shells of the freshwater snail Melanoides tuberculata, from lakes in the Ethiopian Rift Valley  

Microsoft Academic Search

Carbon and oxygen isotope ratios in the shells of the freshwater snail Melanoides tuberculata yield information on the isotopic composition of the water in which the shell was formed, which in turn relates to climatic conditions prevailing during the snails' life span. Melanoides is particularly important because it is widespread in Quaternary deposits throughout Africa and Asia and is ubiquitous

Melanie J. Leng; Angela L. Lamb; Henry F. Lamb; Richard J. Telford

1999-01-01

28

Interaction between the Intermediate Host of Schistosomiasis in Brazil Biomphalaria glabrata (Planorbidae) and a Possible Competitor Melanoides tuberculata (Thiaridae): I. Laboratory Experiments  

Microsoft Academic Search

The biological control of Biomphalaria glabrata, intermediate host of Schistosoma mansoni, is one the accepted options to fight schistosomiasis. One of the most promising candidates to control B. glabrata is the snail Melanoides tuberculata, a potential competitor. However, the mechanisms of interaction between the two species are not clear. Our objective is to determine if M. tuberculata indeed compete with

Alexandre Giovanelli; Cesar Luiz; Pinto Ayres; Coelho da Silva

29

Population dynamics of Melanoides tuberculata (Thiaridae) snails in a desert spring, United Arab Emirates and infection with larval trematodes  

Microsoft Academic Search

A dense population of Melanoides tuberculata was found at a brackish (5.93–6.98%) desert spring in the United Arab Emirates. A total of 232–300 snails were measured and\\u000a examined for larval trematodes during the period January 1990 to January 1991. The relative abundance of various size classes\\u000a of the snail has shown that the mass release of young snails occurred twice

Naim S. Ismail; Arif M. S. Arif

1993-01-01

30

Spatial and temporal patterns of parthenogenesis and parasitism in the freshwater snail Melanoides tuberculata.  

PubMed

The Red Queen hypothesis predicts that sex should be more common in populations heavily infested with parasites, than in those without. This hypothesis was investigated in the aquatic snail Melanoides tuberculata, in which both sexual and parthenogenetic individuals exist in natural populations, and some populations are heavily infested by trematodes. The presence of fertile males and the higher genetic diversity of bisexual populations are indicative of sexual reproduction. We compared sites in 1990, 1999, and 2001, and we looked for a positive correlation between male and parasite frequencies. Male frequency was not correlated with the frequency of individuals infected by trematodes. This lack of correlation was reconfirmed in a retrospective power analysis. In a period of 9 years, male frequencies decreased but infection levels increased. These results do not support the Red Queen hypothesis. In samples with high male frequency the number of embryos was low, perhaps indicating that males may have a negative effect on embryo numbers. This effect of males on fitness could perhaps suggest that the cost of sex is fewer embryos. The reduction in embryo numbers may also represent a trade-off between mating and egg production costs. PMID:15669970

Ben-Ami, F; Heller, J

2005-01-01

31

Did life history evolve in response to parasites in invasive populations of Melanoides tuberculata?  

NASA Astrophysics Data System (ADS)

Enemy release and rapid evolution are often assumed to promote biological invasions. In the parthenogenetic snail Melanoides tuberculata, one invasive strain (MAD) was assumed to benefit from enemy release until a heavily parasitized population was found in Colombia (in the area of introduction). This population is prosperous despite important losses in the reproductive potential due to a high prevalence of a trematode that castrates snails. We studied genetic variation in life-history traits among five populations from the invaded area to test whether life histories had recently evolved in the parasitized population in such a way that snails have more chance to reproduce before being parasitized. We find significant genetic differences among populations, though they are not in the expected direction. Individuals from the parasitized population were smaller at birth, grew slower, and reproduced later and at a bigger size than individuals from the non-parasitized populations. We conclude that the life-history traits of this snail strain did not need to evolve in order to allow population renewal in the invaded area, even in the presence of parasites. This implies that enemy release and/or rapid evolution were not necessary for this strain to invade.

Escobar, Juan Sebastián; Correa, Ana Cristina; David, Patrice

32

FIRST RECORD OF MELANOIDES TUBERCULATA (MÜLLER, 1774) (GASTROPODA: PROSOBRANCHIA: THIARIDAE) IN THE STATE OF PARAÍBA (BRAZIL) AND ITS POSSIBLE ECOLOGICAL IMPLICATIONS  

Microsoft Academic Search

This paper relates the first record of Melanoides tuberculata (Müller, 1774) in the State of Paraíba, Brazil. The data concerning the distribution of this species in the State showed that its ability to occupy new ecotopes is very high, because it was found in five places with well established populations, from the littoral zone to the \\

Ronilson José Paz; Takako Watanabe; Maria Priscila; M. Dijck; Francisco J. P. Abílio

33

Metacercariae of centrocestus formosanus (Nishigori, 1924) (Trematoda) in freshwater Fishes in México and their transmission by the Thiarid Snail Melanoides tuberculata  

Microsoft Academic Search

We report for the first time Centrocestus formosanus (Nishigori, 1924) Price, 1932 (Trematoda: Heterophyidae) metacercariae parasitizing natural populations of Xiphophorus hellen (Poeciliidae) and Gobiomorus dormitor (Gobiidae) in Mexico. Adult forms confirming the specific identity were recovered from experimental infections of domestic chicks and laboratory mice. The first intermediate host of this parasite is Melanoides tuberculata, its role in transmission of

1995-01-01

34

Variation of shell shape in the clonal snail Melanoides tuberculata and its consequences for the interpretation of fossil series.  

PubMed

Interpreting paleontological data is difficult because the genetic nature of observed morphological variation is generally unknown. Indeed, it is hardly possible to distinguish among several sources of morphological variation including phenotypic plasticity, sexual dimorphism, within-species genetic variation or differences among species. This can be addressed using fossil organisms with recent representatives. The freshwater snail Melanoides tuberculata ranks in this category. A fossil series of this and other species have been studied in the Turkana Basin (Kenya) and is presented as one of the best examples illustrating the punctuated pattern of evolution by the tenants of this theory. Melanoides tuberculata today occupies most of the tropics. We studied variation of shell shape in natural populations of this parthenogenetic snail using Raup's model of shell coiling. We considered different sources of variation on estimates of three relevant parameters of Raup's model: (1) variation in shell shape was detected among clones, and had both genetic and environmental bases; (2) sexual dimorphism, in those clones in which males occur, appeared as an additional source of shell variation; and (3) ecophenotypic variation was detected by comparing samples from different sites and years within two clones. We then tested the performance of discriminant function analyses, a classical tool in paleontological studies, using several datasets. Although the three sources of variation cited above contributed significantly to the observed morphological variance, they could not be detected without a priori knowledge of the biological entities studied. However, it was possible to distinguish between M. tuberculata and a related thiarid species using these analyses. Overall, this suggests that the tools classically used in paleontological studies are poorly efficient when distinguishing between important sources of within-species variation. Our study also gives some empirical bases to the doubts cast on the interpretation of the molluscan series of the Turkana Basin. PMID:10937226

Samadi, S; David, P; Jarne, P

2000-04-01

35

Parasitological and molecular study of the furcocercariae from Melanoides tuberculata as a probable agent of cercarial dermatitis.  

PubMed

Cercarial dermatitis is caused by animal schistosomes in many parts of the world including Iran. Various stages of the parasites have been studied in intermediate and definitive hosts in northern and southwestern Iran; however, no molecular investigation for species identification and classification of these agents has been carried out, so far. In the present study, more than 3,800 aquatic snails were collected from water sources of Khuzestan, southwest Iran. The snails were identified as Lymnaea gedrosiana, Radix auricularia, Melanoides tuberculata, Melanopsis sp. and Physa acuta. They were examined for schistosome cercariae. Two specimens of M. tuberculata were infected with ocellate furcocercariae belonging to the family Schistosomatidae. Molecular studies were carried on these schistosomatid samples. Both samples belong to an unknown schistosome species and genus in sister position to Gigantobilharzia-Dendritobilharzia clade. They differ from other species in their ITS sequence region as well as in their intermediate host specificity--This is one of the first reports on schistosome cercariae from M. tuberculata and the first including molecular data. Due to adaptability and invasiveness of this snail species, this new schistosome species, as a potential causative agent of cercarial dermatitis in humans, needs to be studied further. PMID:21046153

Karamian, Mehdi; Aldhoun, Jitka A; Maraghi, Sharif; Hatam, Gholamreza; Farhangmehr, Babak; Sadjjadi, Seyed Mahmoud

2010-11-03

36

Hybridization and invasiveness in the freshwater snail Melanoides tuberculata: hybrid vigour is more important than increase in genetic variance.  

PubMed

Many invasive taxa are hybrids, but how hybridization boosts the invasive process remains poorly known. We address this question in the clonal freshwater snail Melanoides tuberculata from Martinique, using three parental and two hybrid lines. We combine an extensive field survey (1990-2003) and a quantitative genetic experiment to show that hybrid lines have outcompeted their parents in natural habitats, and that this increased invasiveness co-occurred with pronounced shifts in life-history traits, such as growth, fecundity and juvenile size. Given the little time between hybrid creation and sampling, and the moderate standing genetic variance for life-history traits in hybrids, we show that some of the observed trait changes between parents and hybrids were unlikely to arise only by continuous selection. We therefore suggest that a large part of hybrid advantage stems from immediate heterosis upon hybridization. PMID:15842482

Facon, B; Jarne, P; Pointier, J P; David, P

2005-05-01

37

[The distribution and possible competition between Melanoides tuberculata and Tarebia granifera (Prosobranchia: Thiaridae) in Lake Hanabanilla, Cuba].  

PubMed

A study was carried out along three years, on distribution and possible competence between the two thiarid species present in Lake Hanabanilla, Cuba: Melanoides tuberculata and Tarebia granifera. Both species presented significant differences as to its abundance within a determined microhabitat, but they could match their densities for the total sampled area. These variations were mainly due to the ratio of juveniles in each species. Interaction was only detected when high abundance values were reached and some limitation resource existed (mainly in the nearest area to the shore). Both thiarids presented a high nest width, but Tarebia granifera was slightly higher; besides, this species was dominant at the end of the study at most of the sampled areas. PMID:9805077

Gutíerrez Amador, A; Perera de Puga, G; Yong Cong, M; Ferrer López, J R; Sánchez Noda, J

1995-01-01

38

Possible competitive displacement of planorbids by Melanoides tuberculata in Minas Gerais, Brazil  

Microsoft Academic Search

Several species of snails, including Pomacea haustrum, Marisa cornuarietis and Helisoma duryi, have been identified as probable competitors and\\/or predators of planorbid intermediate hosts of Schisto- soma. During the last few years, studies carried out in the Caribbean region have shown reductions and even disappearances of populations of Biomphalaria glabrata and B. straminea in breeding places where the snail Melanoides

Carlos Tito Guimarães; Cecília Pereira de Souza; Delza de Moura Soares

2001-01-01

39

Interaction between the intermediate host of Schistosomiasis in Brazil Biomphalaria glabrata (Planorbidae) and a possible competitor Melanoides tuberculata (Thiaridae): I. Laboratory experiments.  

PubMed

The biological control of Biomphalaria glabrata, intermediate host of Schistosoma mansoni, is one the accepted options to fight schistosomiasis. One of the most promising candidates to control B. glabrata is the snail Melanoides tuberculata, a potential competitor. However, the mechanisms of interaction between the two species are not clear. Our objective is to determine if M. tuberculata indeed compete with B. glabrata, using two laboratory experiments. In Experiment 1, we tested the effect of the presence of M. tuberculata on the fecundity and mortality rates of B. glabrata. In Experiment 2, we tested if there was a direct or indirect interaction between the two species. In Experiment 1, M. tuberculata was eliminated after the peak in reproductive activity of B. glabrata. In Experiment 2, B. glabrata produced more egg masses when raised with M. tuberculata. The conditions leading to this unexpected positive effect of M. tuberculata on the fecundity of B. glabrata need further clarification, but emphasize that detailed studies of the interaction between these species in the conditions of the local environment should be considered. PMID:12048567

Giovanelli, Alexandre; Vieira, Marcus Vinícius; Coelho da Silva, Cesar Luiz Pinto Ayres

2002-04-01

40

The molluscicidal activity of niclosamide (Bayluscide WP70(R)) on Melanoides tuberculata (Thiaridae), a snail associated with habitats of Biomphalaria glabrata (Planorbidae).  

PubMed

The aim of this study was to determine the toxicity of niclosamide (Bayluscide (R)) on Melanoides tuberculata and Biomphalaria glabrata under laboratory conditions. The latter species is the intermediate host of Schistosoma mansoni (Sambon 1917). M. tuberculata was successfully used as competitor of B. glabrata in biological control programs in French West Indies. Both molluscicide and biological control using M. tuberculata have proved to be successful in reducing the population density of B. glabrata. The associated use of molluscicide in this area would be an effective measure if M. tuberculata were less susceptibility to the molluscicide than B. glabrata. Three hundreds individuals each of B. glabrata and of M. tuberculata, collected in Sumidouro, State of Rio de Janeiro, were used in the experiment. The molluscs were exposed to 14 different concentrations of niclosamide as recommended by the World Health Organization. Probit analysis was used to determine the LC 50 and LC 90. The LC 50 and LC 90 values for B. glabrata were 0.077 mg/l and 0.175 mg/l, respectively and the LC 50 and LC 90 values for M. tuberculata were 0.082 mg/l and 0.221 mg/l respectively. As the lethal concentrations of niclosamide were approximately the same to both species, this could be a disadvantage when controlling B. glabrata with niclosamide in an area of M. tuberculata occurrence. It might therefore be preferable to utilize the latex extracted from the Euphorbia splendens, which presented a much higher efficiency for B. glabrata than to M. tuberculata. PMID:12219145

Giovanelli, Alexandre; Silva, Cesar Luiz Pinto Ayres Coelho da; Medeiros, Luisa; Vasconcellos, Maurício Carvalho de

2002-07-01

41

The molluscicidal activity of the latex of Euphorbia splendens var. hislopii on Melanoides tuberculata (Thiaridae), a snail associated with habitats of Biomphalaria glabrata (Planorbidae).  

PubMed

The use of the latex of Euphorbia splendens var. hislopii was considered as an effective control method for Biomphalaria glabrata in Sumidouro, Rio de Janeiro. However, the appearance and expansion of the snail Melanoides tuberculata since August 1997, with the concomitant reduction of the population of B. glabrata suggest that competitive exclusion might be taking place. Depending on the susceptibility of the thiarid to the E. splendens toxin, the natural control that is occurring could be interrupted by the employment of the latex if the planorbid were less susceptible to the toxin. The aim of this study is to investigate the molluscicidal activity of the latex on M. tuberculata. We used 420 M. tuberculata, from Sumidouro. Fourteen different latex concentrations were tested using World Health Organization general methodology. Probit analysis was used for LD90 and LD50 determination. The LD50 was 3.57 mg/l and LD90 was 6.22 mg/l. At the highest concentration (10 mg/l) there was no survival. No significant differences among replicas (chi2 = 8.31; gl = 13; p > 0.05) were found. The LD90 dose for M. tuberculata was 13.8 times greater than that for B. glabrata, so that the molluscicide in the presence of the thiarid may have a synergic effect on reduction of Biomphalaria populations. PMID:11285483

Giovanelli, A; da Silva, C L; Medeiros, L; de Vasconcellos, M C

2001-01-01

42

The Effect of Chemical Treatments on Red-Rim Melania Melanoides tuberculata, an Exotic Aquatic Snail that Serves as a Vector of Trematodes to Fish and Other Species in the USA  

Microsoft Academic Search

The red-rim melania Melanoides tuberculata, a subtropical and tropical snail, is a nonindigenous species that has become established and is spreading in the United States. Of concern is the potential of the red-rim melania to displace native snail populations and to transmit trematodes that cause serious problems. One of these, a fish gill trematode, Centrocestus formosanus, has negatively affected U.S.

Andrew J. Mitchell; Melissa S. Hobbs; Thomas M. Brandt

2007-01-01

43

INTERACTION BETWEEN THE INTERMEDIATE HOST OF SCHISTOSOMIASIS IN BRAZIL BIOMPHALARIA GLABRATA (SAY 1818) AND A POSSIBLE COMPETITOR MELANOIDES TUBERCULATA  

Microsoft Academic Search

ABSTRACT The snail Melanoidestuberculata has been used successfully in the control of Biomphalaria glabrata, intermediate host of Schistosoma mansoni. Melanoidestuberculata has been introduced in Brazil, but its effects on populations,of B. glabrata have not yet been evaluated,in the field. Here we describe the population dynamics,of B. glabrata before and,after the invasion by M. tuberculata in an irrigation channel,in the municipality

Alexandre Giovanelli; Marcus V. Vieira; Cesar L. P. A. Coelho; Da Silva

44

Microsatellite and morphological analysis of population structure in the parthenogenetic freshwater snail Melanoides tuberculata: insights into the creation of clonal variability.  

PubMed

The distribution of variability was studied at various geographical scales in the tropical freshwater snail Melanoides tuberculata, in order to analyse the role of factors shaping this distribution, including the mating system and population dynamics. This parthenogenetic polyploid species reproduces mainly asexually, with males occurring at low frequency. About 800 individuals (38 sites) were sampled from Africa and the Middle East, where the species originated, and from recently colonized habitats in South and Central America, and especially the island of Martinique. We first described variation of general aspects and ornamentation of the shells. This analysis confirms the existence of discrete morphs. Second, individuals were studied at three microsatellite loci, showing that each morph is a genetic clone with some minor variation compatible with models of microsatellite evolution. The genetic analysis also showed much more variation within than between clones. However, two populations from Africa exhibited a large amount of variability, and a mixture of sexual and asexual reproduction might explain these genetic patterns. The worldwide distribution of variability is, therefore, compatible with the African origin of the species, and the introduction of a few clones in other parts of the world. These results also suggest that the distribution of variability in Martinique is influenced by flooding events, and that two morphs from Martinique can be interpreted as hybrids between two pre-existing morphs, based on morphological, genetic and geographical arguments. PMID:10447855

1999-07-01

45

The introduction of Melanoides tuberculata (Mollusca: Thiaridae) to the island of Saint Lucia (West Indies) and its role in the decline of Biomphalaria glabrata, the snail intermediate host of Schistosoma mansoni.  

PubMed

A malacological survey was carried out in May 1992 in the whole hydrographic system of Saint Lucia 11 years after the end of a biological control programme to eliminate Biomphalaria glabrata, the snail intermediate host of Schistosoma mansoni. A competitor snail, Melanoides tuberculata, was introduced to Saint Lucia in 1978 and field experiments in several habitats were conducted by Prentice between 1978 and 1986. At the present time M. tuberculata is the most common freshwater snail in Saint Lucia. The results of the survey, undertaken in sites where B. glabrata occurred in large populations in the past showed (i) the absence of the snail hosts from seven sites now extensively colonized by the competitor (ii) the presence of B. glabrata in low or very low densities in 17 sites together with the competitor and (iii) the presence of the intermediate hosts in large populations in only two sites where M. tuberculata was absent. These results confirm the positive results observed by Prentice. The presence of another planorbid snail, B. straminea, is reported for the first time in Saint Lucia. PMID:8103624

Pointier, J P

1993-06-01

46

Interaction Between The Intermediate Host Of Schistosomiasis In Brazil, Biomphalaria Glabrata (Say, 1818) And A Possible Competitor, Melanoides Tuberculata (Muller, 1774): A Field Study  

Microsoft Academic Search

The snail Melanoidestuberculata has been used successfully in the control of Biomphalaria glabrata, intermediate host of Schistosoma mansoni. Melanoidestuberculata has been introduced in Brazil, but its effects on populations of B. glabrata have not yet been evaluated in the field. Here we describe the population dynamics of B. glabrata before and after the invasion by M. tuberculata in an irrigation

ALEXANDRE GIOVANELLI; MARCUS V. VIEIRA; CESAR L. P. A. COELHO

2005-01-01

47

Statistical discrimination of sex in Melanoides tuberculata (Gastropoda: Thiaridae)  

Microsoft Academic Search

Systematists may rely on morphometric differences among samples of specimens for the recognition of living and fossil species, even though morphometric differentiation may be caused by non-genetic factors, such as ecophenotypy, differential growth rates and taphonomic mixing. When genetic differences between sexes or among closely related species are expressed as differences in the morphology of the individual or population, potentially

JOSEPH HELLER; OZ BEN-YEHUDA

1996-01-01

48

Parasitological and molecular study of the furcocercariae from Melanoides tuberculata as a probable agent of cercarial dermatitis  

Microsoft Academic Search

Cercarial dermatitis is caused by animal schistosomes in many parts of the world including Iran. Various stages of the parasites\\u000a have been studied in intermediate and definitive hosts in northern and southwestern Iran; however, no molecular investigation\\u000a for species identification and classification of these agents has been carried out, so far. In the present study, more than\\u000a 3,800 aquatic snails

Mehdi Karamian; Jitka A. Aldhoun; Sharif Maraghi; Gholamreza Hatam; Babak Farhangmehr; Seyed Mahmoud Sadjjadi

2011-01-01

49

Biological control of Biomphalaria glabrata and B. straminea by the competitor snail Thiara tuberculata in a transmission site of schistosomiasis in Martinique, French West Indies.  

PubMed

In Martinique, intestinal schistosomiasis was discovered at the beginning of this century. The intermediate host snail, Biomphalaria glabrata, was considered in the past as a common species in the different habitats of the island, but during the last decade it has been found only in water-cress beds. Several of these water-cress cultures contained mixed populations of B. glabrata and B. straminea. Moreover, these habitats also constituted transmission sites for Schistosoma mansoni infection. In 1979 the thiarid snail Thiara ( = Melanoides) tuberculata was discovered in Madame river, Fort-de-France, and in the following years at other sites. In 1983 a programme of biological control using this snail was started in two groups of water-cress beds. In 1981-1982 the study site, Roxelane valley, sheltered important populations of B. glabrata (45-256 individuals/m2) and of B. straminea (2-30 ind./m2). In January 1983 the competitor T. tuberculata was introduced into the two groups of water-cress beds (1.3 and 1.7 ind./m2 respectively) and during subsequent years snail population sampling was carried out. The results showed rapid colonization by the competitor snail, whose densities reached 178 and 325 ind./m2 in November 1983 and a maximum of 9941 and 13,388 ind./m2 in October 1984. During that time, B. glabrata populations declined: 153 and 41 ind./m2 in November 1983, 4 and 0 ind./m2 in October 1984, and 0 ind./m2 in the two groups of water-cress beds in October 1985. A similar phenomenon was observed for B. straminea. Since October 1985 neither planorbid species has been found by exhaustive sampling of the habitats.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2513787

Pointier, J P; Guyard, A; Mosser, A

1989-06-01

50

Morphologic, cytometric and functional characterisation of abalone (Haliotis tuberculata) haemocytes.  

PubMed

This work presents the first detailed microscopic and functional analysis of the haemocytes of an abalone; the European Haliotis tuberculata. It is shown that in contrast to the situation in bivalves, only very few basophilic "granulocytes" could be found and exclusively with a histological stain. Neither flow cytometry, phase contrast observation nor transmission electron microscopy were able to detect any granular cells. The large majority of cells was constituted of "hyalinocytes", which could be sorted by flow cytometry, for the first time, into small (blast-like) and large cells. This permits a detailed analysis of haemocytes and especially of the lowly represented blast-like cells. The differences in haemolymph cell composition between bivalves and gastropods is reviewed in depth and discussed in view of the new data we present. Most of the abalone haemocytes analysed harbour many vacuoles, large glycogen deposits, lipid inclusions and acidic compartments. However, although the number of these "inclusions" was rather variable in between individual hyalinocytes, these experiments did not allow to discern subpopulations using these criteria, and the population appears more as a "differentiation continuum". Haemocytes adhere very rapidly and are immunologically active as they quickly phagocytose latex beads and zymozan particles. This study is the first step towards understanding the H. tuberculata immune system by adapting new tools to gastropods and in providing a first detailed morpho-functional study of their haemocytes. PMID:18289878

Travers, Marie-Agnès; Mirella da Silva, Patricia; Le Goïc, Nelly; Marie, Dominique; Donval, Anne; Huchette, Sylvain; Koken, Marcel; Paillard, Christine

2007-10-09

51

Two new species of Phyllagathis related to P. tuberculata ( Melastomataceae ) from Peninsular Malaysia  

Microsoft Academic Search

Phyllagathis tuberculataKing and two closely allied new species,P. magnificaA. Weber andP. stoneiA. Weber, are described and illustrated. Within the genus, these species form a distinct and isolated group which is restricted to Peninsular Malaysia.P. tuberculata occurs in Perak (probably confined to G. Bujang Melaka),P. magnifica andP. stonei are found in the mountains on the Pahang\\/Selangor border (Genting Highlands, Gombak valley).

Anton Weber

1987-01-01

52

Terrestrial locomotion of the New Zealand short-tailed bat Mystacina tuberculata and the common vampire bat Desmodus rotundus  

Microsoft Academic Search

Bats (Chiroptera) are generally awkward crawlers, but the common vampire bat (Desmodus rotundus) and the New Zealand short-tailed bat (Mystacina tuberculata) have independently evolved the ability to manoeuvre well on the ground. In this study we describe the kinematics of locomotion in both species, and the kinetics of locomotion in M. tuberculata. We sought to determine whether these bats move

Daniel K. Riskin; Stuart Parsons; William A. Schutt; Gerald G. Carter; John W. Hermanson

2006-01-01

53

Suitability of three red macroalgae as a feed for the abalone Haliotis tuberculata coccinea Reeve  

Microsoft Academic Search

A 60-day feeding trial was conducted to assess the suitability of three red algae, Hynea spinella, Hynea musciformis and Gracilaria cornea, as potential feed for the culture of juvenile abalone, Haliotis tuberculata coccinea R. Seaweeds were reared in a biofiltration unit with fishpond waste water effluents. The three algal species were found to contain high protein contents which would be

M. P. Viera; J. L. Gómez Pinchetti; G. Courtois de Vicose; A. Bilbao; S. Suárez; R. J. Haroun; M. S. Izquierdo

2005-01-01

54

Feeding by the short?tailed bat (Mystacina tuberculata) on fruit and possibly nectar  

Microsoft Academic Search

New Zealand's short?tailed bat (Mystacina tuberculata Gray, 1843) feeds on fruit, insects, and possibly nectar in North Island kauri (Agathis australis) forest. Fruits eaten by members of a colony of 500 bats in May included those of Freycinetia baueriana (Pandanaceae), Collospermum hastatum, and C. microspermum (Liliaceae). Pollen analyses of bat guano, and of the stomach contents of 4 short?tailed bats

M. J. Daniel

1976-01-01

55

The New Zealand short-tailed bat, Mystacina tuberculata; a review of present knowledge  

Microsoft Academic Search

Research on the New Zealand short-tailed bat is reviewed from published and unpublished studies. The monotypic family Mystacinidae, at present assigned with the Vespertilionidae and Molossidae to the Vespertilionoidea, is considered to be best re-associated with the Emballonuridae and Noctilionidae in the Emballonuroidea. The two subspecies of Mystacina tuberculata Gray are retained pending elevation to specific status. The dichotomy of

M. J. Daniel

1979-01-01

56

Carnosine protects against the neurotoxic effects of a serotonin-derived melanoid.  

PubMed

Anesthesia-related postoperative cognitive dysfunction (POCD) leads to morbidity in the elderly. Lipid peroxidative byproducts (i.e. acrolein) accumulate in aging and may play a role. Sevoflurane, an inhaled anesthetic, sequesters acrolein and enhances the formation of a serotonin-derived melanoid (SDM). SDM may be a biologically relevant polymeric melanoid that we previously showed exhibits redox activity and disrupts lipid bilayers. In this study, we examined the toxicity of SDM in cell culture and looked at protection using L-carnosine. SDM's toxic effects were tested on neuronal-like SH-SY5Y cells, causing an exponential decrease in viability, while human dermal fibroblasts were completely resistant to the toxic effects. SDM brought about morphological changes to differentiated SH-SY5Y cells, particularly to neuronal processes. Co- but not pre-treatment with L-carnosine protected differentiated SH-SY5Y cells exposed to SDM. Our mechanism suggests focal sevoflurane-induced sequestration of age-related acrolein leading to SDM synthesis and neuronal impairment, which is prevented by L-carnosine. PMID:21153702

Brownrigg, Tanner D; Theisen, Christopher S; Fibuch, Eugene E; Seidler, Norbert W

2010-12-14

57

ESPÉCIES EXÓTICAS INVASORAS NA ARBORIZAÇÃO DE VIAS PÚBLICAS DE MARINGÁ-PR  

Microsoft Academic Search

RESUMO Apesar da temática das espécies exóticas invasoras ser recente no meio científico, e praticamente desconhecida pela sociedade, a invasão biológica desencadeada por elas é a segunda maior causa de perda da biodiversidade no planeta. Quando introduzidas em novos ambientes, elas adaptam-se e ocupam agressivamente o espaço de espécies nativas, produzindo desequilíbrios muitas vezes irreversíveis. Este estudo procurou avaliar o

Christopher Thomas Blum; Marília Borgo; André Cesar; Furlaneto Sampaio

2008-01-01

58

Temperature Tolerance of Red-Rim Melania Melanoides tuberculatus, an Exotic Aquatic Snail Established in the United States  

Microsoft Academic Search

The red-rim melania Melanoides tuberculatus (family Thiaridae), a tropical, nonindigenous aquatic snail, has become established and is spreading in the United States. Concerns associated with the spread of this snail include its potential to displace native snail populations and to transmit trematodes. Of particular concern is the gill trematode Centrocestus formosanus now found in U.S. commercial and wild fish stocks.

Andrew J. Mitchell; Thomas M. Brandt

2005-01-01

59

Twenty-four-hour profiles and sleep-related variations of cortisol, thyrotropin and plasma renin activity in healthy african melanoids  

Microsoft Academic Search

The 24-h hormone profiles have been well documented in caucasians living in a temperate climate, but they have never been examined in melanoid subjects under equatorial conditions, with a 12-h light-dark cycle in a hot climate. To establish normal data for this population, blood samples were taken at 10min intervals over 24 h in five healthy young melanoids living in

B. Goichot; G. Brandehberger; A. Buguet; A. Montmayeur; L. Bourdon; P. Bogui; M. Dumas

1995-01-01

60

Cryopreservation of mantle dissociated cells from Haliotis tuberculata (Gastropoda) and postthawed primary cell cultures  

Microsoft Academic Search

Dissociated mantle cells from the gastropod mollusc Haliotis tuberculata were cultured after a freezing–thawing procedure using either 10% dimethyl sulfoxide (Me2SO) or 10% glycerol (Gly) as a cryoprotector. The survival rate of 2-day-old cultured cryopreserved cells after thawing, based on analysis of DNA and protein contents, was nearly 80% in comparison with 2-day-old cultured fresh cells. Cells thawed after cryopreservation

J.-M Poncet; A Serpentini; E Boucaud-Camou; J.-M Lebel

2002-01-01

61

The ultrastructure of the spermatozoon of Paradynomene tuberculata Sakai, 1963 (Crustacea, Brachyura, Dynomenidae): Synapomorphies with dromiid sperm  

NASA Astrophysics Data System (ADS)

The dynomenid spermatozoon, exemplified here by Paradynomene tuberculata, resembles the spermatozoa of the Dromiidae, Homolidae and lyreidine raninoids and differs markedly from those of other crabs (the heterotreme, thoracotremes, raninines and raninoidines) in the depressed, discoidal form of the acrosome and the capitate form of the perforatorium. Four or five apparent dynomenid—dromiid sperm synapomorphies are recognizable. (1) Dynomenids ( P. tuberculata) and dromiids differ from homolids and lyreidines in the greater depression of the acrosome (ratio of length to width=0.3); (2) the capitate head of the perforatorium is bilaterally prolonged in P. tuberculata as in dromiids though symmetrical in homolids; (3) dynomenid and dromiid sperm lack the—albeit variably developed—posterior median process of the nucleus seen in homolids, anomurans, raninoids and lower heterotremes; (4) P. tuberculata, like dromiids and less distinctly homolids, has an apical protuberance of subopercular material through the opercular perforation, unknown in other crabs, being distinct from the apical button of thoracotreme sperm; (5) a less certain synapomorphy is the anterolateral electron-pale peripheral zone of the acrosome. These synapomorphies endorse a sister-group relationship of dynomenids and dromiids, P. tuberculata sperm differs notably from the sperm of dromiids in the more complex zonation of the acrosome. The perforatorium lacks the radial rays (“spiked wheel”) of homolid sperm and does not show the “amoeboid” form seen in lyreidines. Absence of internal corrugations of the perforatorial chamber is a major difference from all examined raninids. Centrioles are only very tentatively identifiable. Nuclear arms are absent in glutaraldehyde fixed spermatozoa of P. tuberculata and have not been observed in the dromiid Petalomera lateralis but are present as three small radial vertices in the dromiid Dromidiopsis edwardsi and in homolids. P. tuberculata resembles Petalomera lateralis in the large size of the sperm nucleus relative to the acrosome compared with D. edwardsi and homolids.

Jamieson, B. G. M.; Guinot, D.; de Forges, B. Richer

1993-10-01

62

Floral scent composition of Plumeria tuberculata analyzed by HS-SPME.  

PubMed

The headspace volatile compounds of the flowers of Plumeria tuberculata Lodd. were analyzed by solid phase microextraction coupled with capillary gas chromatography/mass spectrometry. Twenty-five compounds were identified, representing 100% of the total composition. The volatile fraction was characterized by oxygenated monoterpenes (79.6%), oxygenated sesquiterpenes (8.4%), sesquiterpene hydrocarbons (7.6%), and benzenoid esters (2.6%). The major components were geraniol (34.9%), citronelol (21.5%) and geranial (16.2%), and they were found to make the major contribution to the typical scent of this flower. PMID:22428259

Báez, Disnelys; Pino, Jorge A; Morales, Diego

2012-01-01

63

Gene expression patterns of abalone, Haliotis tuberculata, during successive infections by the pathogen Vibrio harveyi.  

PubMed

Since 1998, episodic mass mortality of the abalone Haliotistuberculata has been observed along the northern Brittany coast of France caused by a complex interaction among the host, pathogen and environmental factors. In the present study, abalone were submitted to two successive infections with the pathogen Vibrioharveyi under controlled conditions. During the first challenge, infection by V.harveyi resulted in 64% mortality of mature abalone. After a second infection of those surviving the first challenge, only 44% mortality was observed. Physiological variability in the host response appears to be a major determinant in susceptibility to V.harveyi. In order to isolate differentially expressed genes in H.tuberculata challenged with this bacterium, suppression subtractive hybridization (SSH) cDNA libraries were constructed from muscle of moribund abalone (susceptibles), surviving individuals (apparently resistant to the bacterium) and control (unexposed) animals. Of the 1152 clones sequenced, 218 different partial cDNA sequences were obtained and represented 69 known genes. Of these, 65 were identified for the first time in H.tuberculata. Using real-time PCR, a time-course study was conducted on 19 of the genes identified by SSH. A majority of differentially expressed transcripts were down-regulated in susceptible individuals as compared to their resistant counterparts. Bacterial challenge of abalone resulted in the up-regulation of three transcripts (encoding ferritin, heat shock protein HSP84 and fatty acid binding protein FABP) in those that survived exposure to V.harveyi. This study has identified potential candidates for further investigation into the functional basis of resistance and susceptibility to summer vibriosis outbreaks in abalone. PMID:20692263

Travers, Marie-Agnès; Meistertzheim, Anne-Leila; Cardinaud, Marion; Friedman, Carolyn S; Huchette, Sylvain; Moraga, Dario; Paillard, Christine

2010-08-06

64

Characterization of abalone Haliotis tuberculata-Vibrio harveyi interactions in gill primary cultures.  

PubMed

The decline of European abalone Haliotis tuberculata populations has been associated with various pathogens including bacteria of the genus Vibrio. Following the summer mortality outbreaks reported in France between 1998 and 2000, Vibrio harveyi strains were isolated from moribund abalones, allowing in vivo and in vitro studies on the interactions between abalone H. tuberculata and V. harveyi. This work reports the development of primary cell cultures from abalone gill tissue, a target tissue for bacterial colonisation, and their use for in vitro study of host cell-V. harveyi interactions. Gill cells originated from four-day-old explant primary cultures were successfully sub-cultured in multi-well plates and maintained in vitro for up to 24 days. Cytological parameters, cell morphology and viability were monitored over time using flow cytometry analysis and semi-quantitative assay (XTT). Then, gill cell cultures were used to investigate in vitro the interactions with V. harveyi. The effects of two bacterial strains were evaluated on gill cells: a pathogenic bacterial strain ORM4 which is responsible for abalone mortalities and LMG7890 which is a non-pathogenic strain. Cellular responses of gill cells exposed to increasing concentrations of bacteria were evaluated by measuring mitochondrial activity (XTT assay) and phenoloxidase activity, an enzyme which is strongly involved in immune response. The ability of gill cells to phagocyte GFP-tagged V. harveyi was evaluated by flow cytometry and gill cells-V. harveyi interactions were characterized using fluorescence microscopy and transmission electron microscopy. During phagocytosis process we evidenced that V. harveyi bacteria induced significant changes in gill cells metabolism and immune response. Together, the results showed that primary cell cultures from abalone gills are suitable for in vitro study of host-pathogen interactions, providing complementary assays to in vivo experiments. PMID:23756730

Pichon, Delphine; Cudennec, Benoit; Huchette, Sylvain; Djediat, Chakib; Renault, Tristan; Paillard, Christine; Auzoux-Bordenave, Stéphanie

2013-06-12

65

Transmission Efficiency of Two Flea Species ( Oropsylla tuberculata cynomuris and Oropsylla hirsuta ) Involved in Plague Epizootics among Prairie Dogs  

Microsoft Academic Search

Plague, caused by Yersinia pestis, is an exotic disease in North America circulating predominantly in wild populations of rodents and their fleas. Black-tailed\\u000a prairie dogs (Cynomys ludovicianus) are highly susceptible to infection, often experiencing mortality of nearly all individuals in a town as a result of plague.\\u000a The fleas of black-tailed prairie dogs are Oropsylla tuberculata cynomuris and Oropsylla hirsuta.

Aryn P. Wilder; Rebecca J. Eisen; Scott W. Bearden; John A. Montenieri; Daniel W. Tripp; R. Jory Brinkerhoff; Kenneth L. Gage; Michael F. Antolin

2008-01-01

66

Primer registro de Centrocestus formosanus (Digenea: Heterophyidae) en Colombia First record of Centrocestus formosanus (Digenea: Heterophyidae) in Colombia  

Microsoft Academic Search

Palabras clave: Centrocestus, Cichlidae, Colombia, Digenea, Melanoides tuberculata, Poeciliidae. Abstract. Centrocestus formosanus (Digenea:Heterophyidae) is reported for the fi rst time from Colombia, parasitizing snails and fi sh from the lake of the Joaquín Antonio Uribe botanical garden, Medellín. Rediae and cercariae were obtained from MAD morphs of the snail Melanoides tuberculata. Metacercariae were found encysted on gills of fi sh

Luz Elena Velásquez; Juan Carlos Bedoya; Astrid Areiza; Imelda Vélez

2006-01-01

67

Evidence for a direct link between stress and immunity in the mollusc Haliotis tuberculata.  

PubMed

Stress is thought to cause increased disease outbreaks and mortality in a number of invertebrates but currently very little information is available on mechanisms linking physiological states of stress and reduced disease resistance in these organisms. In the present study, we examined the possibility that stress alters immune functions, the principal line of defense against pathogens, in a molluscan model, the abalone Haliotis turbeculata. Immune parameters were investigated in abalones subjected to a 15 min mechanical disturbance which, as indicated by noradrenaline and dopamine hemolymphatic levels, resulted in a transient state of physiological stress. During the application of the stressor, immune parameters such as the number of circulating hemocytes, the migratory activity, the phagocytic capacity and the respiratory burst responses of hemocytes, decreased significantly. All parameters returned to initial values within 15-30 min after the end of the disturbance and a transient period of immunostimulation occurred between 100 and 480 min after the stress for all immune parameters except intracellular superoxide anion production. These results indicate that in the abalone H. tuberculata, as in vertebrates, a link exists between stress and the immune system. This may begin to answer why stress and disease outbreaks are linked in shellfish. PMID:12541297

Malham, Shelagh K; Lacoste, Arnaud; Gélébart, Florence; Cueff, Anne; Poulet, Serge A

2003-02-01

68

Extract from the zooxanthellate jellyfish Cotylorhiza tuberculata modulates gap junction intercellular communication in human cell cultures.  

PubMed

On a global scale, jellyfish populations in coastal marine ecosystems exhibit increasing trends of abundance. High-density outbreaks may directly or indirectly affect human economical and recreational activities, as well as public health. As the interest in biology of marine jellyfish grows, a number of jellyfish metabolites with healthy potential, such as anticancer or antioxidant activities, is increasingly reported. In this study, the Mediterranean "fried egg jellyfish" Cotylorhiza tuberculata (Macri, 1778) has been targeted in the search forputative valuable bioactive compounds. A medusa extract was obtained, fractionated, characterized by HPLC, GC-MS and SDS-PAGE and assayed for its biological activity on breast cancer cells (MCF-7) and human epidermal keratinocytes (HEKa). The composition of the jellyfish extract included photosynthetic pigments, valuable ?-3 and ?-6 fatty acids, and polypeptides derived either from jellyfish tissues and their algal symbionts. Extract fractions showed antioxidant activity and the ability to affect cell viability and intercellular communication mediated by gap junctions (GJIC) differentially in MCF-7 and HEKa cells. A significantly higher cytotoxicity and GJIC enhancement in MCF-7 compared to HEKa cells was recorded. A putative action mechanism for the anticancer bioactivity through the modulation of GJIC has been hypothesized and its nutraceutical and pharmaceutical potential was discussed. PMID:23697954

Leone, Antonella; Lecci, Raffaella Marina; Durante, Miriana; Piraino, Stefano

2013-05-22

69

Beneficial Effect of Verminephrobacter Nephridial Symbionts on the Fitness of the Earthworm Aporrectodea tuberculata? †  

PubMed Central

Almost all lumbricid earthworms (Oligochaeta: Lumbricidae) harbor species-specific Verminephrobacter (Betaproteobacteria) symbionts in their nephridia (excretory organs). The function of the symbiosis, and whether the symbionts have a beneficial effect on their earthworm host, is unknown; however, the symbionts have been hypothesized to enhance nitrogen retention in earthworms. The effect of Verminephrobacter on the life history traits of the earthworm Aporrectodea tuberculata (Eisen) was investigated by comparing the growth, development, and fecundity of worms with and without symbionts given high (cow dung)- and low (straw)-nutrient diets. There were no differences in worm growth or the number of cocoons produced by symbiotic and aposymbiotic worms. Worms with Verminephrobacter symbionts reached sexual maturity earlier and had higher cocoon hatching success than worms cured of their symbionts when grown on the low-nutrient diet. Thus, Verminephrobacter nephridial symbionts do have a beneficial effect on their earthworm host. Cocoons with and without symbionts did not significantly differ in total organic carbon, total nitrogen, or total hydrolyzable amino acid content, which strongly questions the hypothesized role of the symbionts in nitrogen recycling for the host.

Lund, Marie B.; Holmstrup, Martin; Lomstein, Bente A.; Damgaard, Christian; Schramm, Andreas

2010-01-01

70

Expression of biomineralisation genes in tissues and cultured cells of the abalone Haliotis tuberculata.  

PubMed

Mollusc shell biomineralisation involves a variety of organic macromolecules (matrix proteins and enzymes) that control calcium carbonate (CaCO3) deposition, growth of crystals, the selection of polymorph, and the microstructure of the shell. Since the mantle and the hemocytes play an important role in the control of shell formation, primary cell cultures have been developed to study the expression of three biomineralisation genes recently identified in the abalone Haliotis tuberculata: a matrix protein, Lustrin A, and two carbonic anhydrase enzymes. Mantle cells and hemocytes were successfully maintained in primary cultures and were evaluated for their viability and proliferation over time using a semi-automated assay (XTT). PCR and densitometric analysis were used to semi-quantify the gene expression and compare the level of expression in native tissues and cultured cells. The results demonstrated that the three genes of interest were being expressed in abalone tissues, with expression highest in the mantle and much lower in the hemocytes and the gills. Biomineralisation genes were also expressed significantly in mantle cells, confirming that primary cultures of target tissues are suitable models for in vitro investigation of matrix protein secretion. PMID:23929462

O'Neill, Matthew; Gaume, Béatrice; Denis, Françoise; Auzoux-Bordenave, Stéphanie

2013-08-09

71

Intra-plant differences in seaweed nutritional quality and chemical defenses: Importance for the feeding behavior of the intertidal amphipod Orchestoidea tuberculata  

NASA Astrophysics Data System (ADS)

As a result of their morphological complexity, large macroalgae show intra-thallus variations in their nutritional composition and secondary metabolite content, which influences the trophic ecology of herbivorous invertebrates, and ultimately their fitness. In this study, we evaluated for the first time the variability in nutritional quality (protein content, carbohydrates, lipids, and total organic matter), secondary metabolites (phlorotannins), and structure (shape and toughness) between blades and stipes of the macroalgae Durvillaea Antarctica. Specifically, we looked at their effect on feeding preference, rate of consumption, absorption efficiency, and growth rate of the amphipod Orchestoidea tuberculata, one of the most abundant organisms on Chilean sandy beaches. Proteins, carbohydrates, total organic matter and phlorotannin contents were significantly higher in blades than in stipes. Preference experiments revealed that the amphipods preferred blades when fresh pieces of blades and stipes were offered at the same time. Similar results were found when artificial food (in which structures of both parts of the alga were standardized) was offered, suggesting that shape and toughness of the two different parts of the alga did not influence preference patterns of O. tuberculata. Absorption efficiency of O. tuberculata was higher on blades compared to stipes. When the amphipods were kept with each of the algal parts separately (i.e. no choice), they consumed a significantly higher amount of stipe, which suggests that O. tuberculata used food quantity to compensate for the lower nutritional quality of stipes. The higher nutritional values of blades compared to stipes appears to explain observed preference patterns by O. tuberculata. Phlorotannin content did not appear to inhibit blade consumption, suggesting that the nutritional quality of the food could be more important than chemical defense in determining food choice in O. tuberculata. Growth did not differ between the amphipods maintained with either blades or stipes (i.e. no choice), which is consistent with the hypothesis of compensatory feeding. To conclude, O. tuberculata can actively select specific parts of an alga and this selection appears to be based on nutritional quality. The capacity for using different feeding strategies allow O. tuberculata, in some cases, to successfully exploit food types with different nutritional qualities.

Duarte, Cristian; Acuña, Karin; Navarro, Jorge M.; Gómez, Iván

2011-10-01

72

Effect of in vitro exposure to zinc on immunological parameters of haemocytes from the marine gastropod Haliotis tuberculata.  

PubMed

Environmental pollutants such as heavy metals exert immunotoxic effects on aquatic organisms. The immune defence of molluscs is comprised of cell-mediated and humoral mechanisms, in which haemocytes play a key role. In this study, a model based on primary cultured haemocytes from the gastropod mollusc Haliotis tuberculata was established to investigate the effects of zinc in vitro. Cells were exposed for 24 h to ZnCl(2) concentrations of 0, 10, 100 or 1000 microM. The effects of zinc on haemocyte parameters were investigated using morphological, spectrophotometric and flow cytometry analysis. Immunotoxicity was reflected by a significant decrease in the number of viable haemocytes (LC(50)(24 h) = 314 microM). Moreover, the cell area was dramatically reduced, and the percentage of rounded cells increased with increasing zinc concentrations. Exposure to 1000 muM zinc induced a significant reduction in acid phosphatase activity, phagocytic activity and reactive oxygen species production in haemocytes. However, several haemocyte parameters increased significantly after 24 h of zinc exposure. In response to a 1000 microM exposure, the phenoloxidase level was 26-fold higher than that of the control, and non-specific esterase activity was increased by 69% above that of the control. These results suggest a relationship between zinc exposure and alterations in the functional responses of haemocytes from H. tuberculata. PMID:20659566

Mottin, Elmina; Caplat, Christelle; Mahaut, Marie-Laure; Costil, Katherine; Barillier, Daniel; Lebel, Jean-Marc; Serpentini, Antoine

2010-07-24

73

Comparative studies on the nutrition of two species of abalone, Haliotis tuberculata Linnaeus and Haliotis discus hannai Ino I. Effects of algal diets on growth and biochemical composition  

Microsoft Academic Search

This study was conducted to examine the nutritional value of eight algal diets for two species of abalone, Haliotis tuberculata and Haliotis discus hannai, by measuring biochemical composition of the algae and relating this to feeding rate, growth and biochemical composition of the animals. Nutritional value of algal diets can be divided into three categories for each species of abalone.

J. P. MERCER; K.-S. MAI; J. DONLON

1993-01-01

74

Comparative studies on the nutrition of two species of abalone, Haliotis tuberculata L. and Haliotis discus hannai Ino. III. response of abalone to various levels of dietary lipid  

Microsoft Academic Search

This study was carried out to evaluate the effects of graded dietary lipid levels on the survival, growth and body composition of Haliotis tuberculata and H. discus hannai. Six purified diets were formulated to provide approximately 25% protein, and a series of graded lipid levels, from 0.63 to 11.58%, in the form of a mixture of corn oil and menhaden

Kangsen Mai; John P. Mercer; John Donlon

1995-01-01

75

Comparative studies on the nutrition of two species of abalone, Haliotis tuberculata L. and Haliotis discus hannai Ino. IV. Optimum dietary protein level for growth  

Microsoft Academic Search

A 100 day growth experiment was conducted to identify the optimum dietary protein level for the juveniles of two species of abalone, Haliotis tuberculata and Haliotis discus hannai. A mixture of vitamin-free casein and gelatin (4.34:1) supplemented with crystalline amino acids was used as the protein source to simulate the amino acid profile of abalone body. Eight purified diets were

Kangsen Mai; John P. Mercer; John Donlon

1995-01-01

76

The introduced snail Melanoides Tuberculatus (Muller, 1774) (Mollusca: Thiaridae) in aquatic ecosystems of the Brazilian semiarid Northeast (Piranhas-Assu River basin, State of Rio Grande do Norte).  

PubMed

Records of the gastropod Melanoides tuberculatus (Müller, 1774), family Thiaridae, in the Piranhas-Assu River basin in Rio Grande do Norte reveal the dispersal of this native Southeast Asian and East African species into aquatic environments of the Brazilian semiarid region, including artificial environments (reservoirs) and lotic systems. The eutrophic conditions of the local waterbodies appear to favor the present situation, where this invasive species reaches extremely high densities, sometimes over 10,000 ind x m(-2) as in Armando Ribeiro Gonçalves Reservoir. These observations indicate the immediate need for new studies on the spatial distribution of the species and its potential impact on the biodiversity and water quality of the waterbodies of the semiarid region of the state. Implantation of regular and systematic monitoring of the aquatic resources of the region is urgently required. PMID:20231954

Santos, C M; Eskinazi-Sant'Anna, E M

2010-02-01

77

Biosynthesis and functions of a melanoid pigment produced by species of the sporothrix complex in the presence of L-tyrosine.  

PubMed

Sporothrix schenckii is the etiological agent of sporotrichosis, the main subcutaneous mycosis in Latin America. Melanin is an important virulence factor of S. schenckii, which produces dihydroxynaphthalene melanin (DHN-melanin) in conidia and yeast cells. Additionally, l-dihydroxyphenylalanine (l-DOPA) can be used to enhance melanin production on these structures as well as on hyphae. Some fungi are able to synthesize another type of melanoid pigment, called pyomelanin, as a result of tyrosine catabolism. Since there is no information about tyrosine catabolism in Sporothrix spp., we cultured 73 strains, including representatives of newly described Sporothrix species of medical interest, such as S. brasiliensis, S. schenckii, and S. globosa, in minimal medium with tyrosine. All strains but one were able to produce a melanoid pigment with a negative charge in this culture medium after 9 days of incubation. An S. schenckii DHN-melanin mutant strain also produced pigment in the presence of tyrosine. Further analysis showed that pigment production occurs in both the filamentous and yeast phases, and pigment accumulates in supernatants during stationary-phase growth. Notably, sulcotrione inhibits pigment production. Melanin ghosts of wild-type and DHN mutant strains obtained when the fungus was cultured with tyrosine were similar to melanin ghosts yielded in the absence of the precursor, indicating that this melanin does not polymerize on the fungal cell wall. However, pyomelanin-producing fungal cells were more resistant to nitrogen-derived oxidants and to UV light. In conclusion, at least three species of the Sporothrix complex are able to produce pyomelanin in the presence of tyrosine, and this pigment might be involved in virulence. PMID:23042177

Almeida-Paes, Rodrigo; Frases, Susana; Araújo, Glauber de Sousa; de Oliveira, Manoel Marques Evangelista; Gerfen, Gary J; Nosanchuk, Joshua D; Zancopé-Oliveira, Rosely Maria

2012-10-05

78

Ultrastructure and Glycoconjugate Pattern of the Foot Epithelium of the Abalone Haliotis tuberculata (Linnaeus, 1758) (Gastropoda, Haliotidae)  

PubMed Central

The foot epithelium of the gastropod Haliotis tuberculata is studied by light and electron microscopy in order to contribute to the understanding of the anatomy and functional morphology of the mollusks integument. Study of the external surface by scanning electron microscopy reveals that the side foot epithelium is characterized by a microvillus border with a very scant presence of small ciliary tufts, but the sole foot epithelium bears a dense field of long cilia. Ultrastructural examination by transmission electron microscopy of the side epithelial cells shows deeply pigmented cells with high electron-dense granular content which are not observed in the epithelial sole cells. Along the pedal epithelium, seven types of secretory cells are present; furthermore, two types of subepithelial glands are located just in the sole foot. The presence and composition of glycoconjugates in the secretory cells and subepithelial glands are analyzed by conventional and lectin histochemistry. Subepithelial glands contain mainly N-glycoproteins rich in fucose and mannose whereas secretory cells present mostly acidic sulphated glycoconjugates such as glycosaminoglycans and mucins, which are rich in galactose, N-acetyl-galactosamine, and N-acetyl-glucosamine. No sialic acid is present in the foot epithelium.

Bravo Portela, I.; Martinez-Zorzano, V. S.; Molist- Perez, I.; Molist Garcia, P.

2012-01-01

79

Summer immune depression associated with increased susceptibility of the European abalone, Haliotis tuberculata to Vibrio harveyi infection.  

PubMed

Haliotis tuberculata mortality outbreaks have occurred in France since 1998 and were attributed to a pathogenic Vibrio harveyi. These mortalities were recorded in September, a month with abalone reproduction and characterised by high seawater temperatures. The importance of gonadal maturation and temperature increase on abalone immunity and susceptibility to V. harveyi infection needed to be clarified. Therefore, an immune survey analyzing a large panel of parameters was performed from June to September 2007 on abalone from the Bay of Brest. The data obtained were put in relation with abalone reproductive status and its susceptibility to V. harveyi. Most parameters showed clear patterns from early to late summer and during gametogenesis, phagocytosis and phenoloxidase activity were reduced, whereas basal reactive oxygen species production and agglutination titres were significantly increased. Total haemocyte counts went up after the partial spawning event at the end of June, and cell complexity diminished. Using a Principal Component Analysis, the "haemolymph profile" was shown to decrease in parallel with spawning and gonadal maturation processes, and reached a minimum just after total spawning. A significant correlation between this "haemolymph profile" and disease susceptibility allowed us to establish for the first time in abalone, a clear concordance between maturation and spawning processes, immune status and abalone susceptibility to V. harveyi. PMID:18786640

Travers, Marie-Agnès; Le Goïc, Nelly; Huchette, Sylvain; Koken, Marcel; Paillard, Christine

2008-08-22

80

Structure of a molluscan hemocyanin didecamer (HtH1 from Haliotis tuberculata) at 12 A resolution by cryoelectron microscopy.  

PubMed

A 12 A resolution three-dimensional density map of the Haliotis tuberculata hemocyanin type 1 (HtH1) didecamer has been obtained by cryoelectron microscopy of unstained molecules and angular reconstitution. The dyad symmetry of the 8 MDa D5 HtH1 didecamer, formed by the pairing of two asymmetric 4 MDa ring-like C5 decamers, is emphasised. The major and minor surface helical grooves of the didecamer are well defined, in agreement with earlier data on molluscan hemocyanins. The location of the obliquely orientated repeating unit, a subunit dimer, within the decamer has been defined. Following interactive extraction of this dimer, several new structural features of the dimer and of the subunit have now emerged with improved detail. The subunit dimer possesses pseudo 2-fold symmetry, resulting from the steric arrangement of the wall domains/functional units (FUs-abcdef) of the two subunits. The arc and collar FUs (g and h) depart from this inherent 2-fold symmetry and are thereby responsible for the asymmetry of the C5 decamer, with the internalised collar/arc complex at one edge of the decamer. The FU heterodimers forming the wall morphological units have a hollow centre, and thus create a series of repeating channels that extend within the wall through all three tiers of the decamer. The connections between the wall and the arc are defined with improved clarity, and evidence is provided to indicate that the arc and collar FU pairs have a homodimeric composition (gg and hh, respectively). Two possibilities for the subunit path within the subunit dimer are presented, which correlate with the available structural, immunolabelling and protease cleavage data from HtH1 and other molluscan hemocyanins. PMID:10756103

Meissner, U; Dube, P; Harris, J R; Stark, H; Markl, J

2000-04-21

81

Moluscos dulceacuícolas exóticos en Chile Exotic freshwater mollusks in Chile  

Microsoft Academic Search

The exotic freshwater mollusk species we report here were collected in wetlands, commercial aquariums, or were given to us by government offi cials who intercepted some exotic species at customs offi ces. Other records came from the specialized literature. These species are Pomacea bridgesii; Helobia sp.; Thiara (Melanoides) tuberculata; Melanoides maculata; Physa sp., Physella venustula and Biomphalaria sp. It is

Ana M. Ramos

2007-01-01

82

Comparative studies on the nutrition of two species of abalone, Haliotis tuberculata L. and Haliotis discus hannai Ino. V. The role of polyunsaturated fatty acids of macroalgae in abalone nutrition  

Microsoft Academic Search

This study was undertaken to evaluate the nutritional role of polyunsaturated fatty acids (PUFA) in dietary macroalgae for the abalone, Haliotis tuberculata and Haliotis discus hannai. The effects of five species of macroalgae (Alarla esculenta, Laminaria digitata, Laminaria saccharina, Palmaria palmata and Ulva lactuca) on specific growth rates (SGR) of the abalone and, the relationship between abalone SGR and fatty

Kangsen Mai; John P. Mercer; John Donlon

1996-01-01

83

Digestion and the Production of Sulphuric Acid by Mollusca  

Microsoft Academic Search

WHILE investigating the food of aquatic Mollusca in Uganda, it was observed that cellulose in the gut contents was being digested. Caelatura hauttecoeuri ruellani (Bgt.), a bivalve, was selected for detailed study and also Melanoides tuberculata tuberculata (Müll.), a snail, which belongs to the Prosobranchia, some members of which possess a crystalline style1.

G. R. Fish

1955-01-01

84

The effects and distribution of metacercaria on the gills of the fish Tilapia zilli (Gervais) 1848  

Microsoft Academic Search

Two cercaria emitted from the snail Melanoides tuberculata are illustrated, one of which encysts on the gills of the fish Tilapia zilli. The parasite is shown to have a marked preference for the anterior gills and especially the middle part of each gill.

R. H. Meakins; J. Kawooya

1973-01-01

85

A molecular phylogeography approach to biological invasions of the New World by parthenogenetic Thiarid snails  

Microsoft Academic Search

The parthenogenetic snail Melanoides tuberculata , present in tropical fresh waters of most of the Old World before 1950, has now invaded the Neotropical area. The phylogeography of this snail was studied to evaluate the pathways and number of such invasions. Because of parthenogenetic reproduction, individuals are structured into genetical clones. Within populations from both the original and invaded areas,

B. FACON; J.-P. POINTIER; M. GLAUBRECHT; C. POUX; P. JARNE; P. DAVID

2003-01-01

86

Factors Affecting the Distribution and Abundance of Two Prosobranch Snails in a Thermal Spring  

Microsoft Academic Search

We studied the distribuiton and abundance of two prosobranch snails (Melanopsis praemorsa and Melanoides tuberculata) in a thermal spring (27°C) in southeast Morocco. Of the physicochemical and ecological parameters measured, food availability and water velocity appeared to be the main factors affecting the spatial distribution of these snails.

Hammou Laamrani; Khalid Khallayoune; Bernard Delay; Jean-Pierre Pointier

1997-01-01

87

Diversity and cercarial shedding of malaco fauna collected from water bodies of Ratnagiri district, Maharashtra  

Microsoft Academic Search

An investigation on the occurrence of snails in the water bodies of five selected sites i.e., Khed, Chiplun, Ratnagiri, Parchuri and Gimvi of district Ratnagiri, Maharashtra (India) was made during April–May 2006. The study revealed occurrence of nine species of snails viz., Indoplanorbis exustus, Lymnaea luteola, L. acuminata, Paludomus obesus, Ferrissia tenuis, Thiara (Melanoides) tuberculata, Bellamya bengalensis, B. dissimilis and

N. Pemola Devi; R. K. Jauhari

2008-01-01

88

Distribution, abundance and diversity of macrozoobenthos in Aiba Reservoir, Iwo, Nigeria  

Microsoft Academic Search

Spatial and seasonal variation in macrozoobenthic composition, abundance and diversity in Aiba Reservoir were investigated bimonthy between June 2004 and April 2005 using a van Veen grab. A depauperate fauna of nine taxa was recorded. Generally, larger numbers of taxa were recorded during the dry season than in the wet season. Melanoides tuberculata and chironomid larvae dominated the macrozoobenthos and

O E Atobatele; O A Ugwumba

2010-01-01

89

Invading freshwater snails and biological control in Martinique Island, French West Indies  

Microsoft Academic Search

Eight alien freshwater snail species were introduced into Martinique Island during the last 50 years. The introduced snails include four planorbids (Biomphalaria straminea, Helisoma duryi, Amerianna carinata and Gyraulus sp.), three thiarids (Melanoides tuberculata, M. amabilis and Tarebia granifera) and one ampullarid (Marisa cornuarietis). Four of these species rapidly colonized the whole Martinican hydrographic system whereas the other four remained

Jean-Pierre Pointier

2001-01-01

90

Life cycle stages of heterophyid trematodes in Vietnamese freshwater fishes traced by molecular and morphometric methods  

Microsoft Academic Search

A survey of digenean zoonotic trematodes infecting snails and fishes in a North Vietnamese freshwater fish culture system revealed shedding of three types of parapleurolophocercous cercariae from the snail host Melanoides tuberculata and the presence of metacercariae within the genus Haplorchis (H. pumilio and H. taichui) and Procerovum sp. in tissues of cultured fishes (silver carp, Indian carp and climbing

Jakob Skov; Per W. Kania; Anders Dalsgaard; Thomas R. Jørgensen; Kurt Buchmann

2009-01-01

91

Food selection by freshwater snails in the Gezira irrigation canals, Sudan  

Microsoft Academic Search

Stomach content analysis was carried out on samples of the freshwater snail species Biomphalaria pfeifferi, Bulinus truncatus, Bulinus forskalii (Pulmonata, Planorbidae), Lymnaea natalensis (Pulmonata, Lymnaeidae), Melanoides tuberculata, Cleopatra bulimoides (Prosobranchia, Thiaridae) and Lanistes carinatus (Prosobranchia, Ampullariidae) from different irrigation canals in Sudan. In order to evaluate overlap in diet selection\\u000a among these species, sites with two or more of the

Henry Madsen

1992-01-01

92

Biological Control of Aquatic Pest Snails by the Black Carp Mylopharyngodon piceus  

Microsoft Academic Search

Some freshwater snail species are severe pests to human health or agriculture. We tested the hypothesis that the fish Mylopharyngodon piceus, the black carp, may serve as a biological control agent of two pest snails, Physella acuta (a bank-dwelling snail) and Melanoides tuberculata (a substratum-dwelling snail). Experiments were carried out in the laboratory and under controlled field conditions. In the

Frida Ben-Ami; Joseph Heller

2001-01-01

93

Biological control and invading freshwater snails.A case study  

Microsoft Academic Search

Introductions of four species of freshwater snails occurred between 1972 and 1996 onto Guadeloupe Island. Two of them, Melanoides tuberculata and Marisa cornuarietis, were subsequently used as biological control agents against Biomphalaria glabrata, the snail intermediate host of intestinal schistosomiasis. In 1996, a general survey was carried out in 134 sites which had already been investigated in 1972. The total

Jean-Pierre Pointier; David Augustin

1999-01-01

94

Heavy metal concentrations in common freshwater snails of Azraq Oasis, Jordan  

Microsoft Academic Search

Heavy metal concentrations in three freshwater snails, an aquatic plant, sediment, and water from Azraq Oasis pools in the Jordanian desert were measured by atomic absorption spectrophotometry. There were significant differences in metal accumulation among snail species. These snails are ranked according to their metal accumulation capacity in the order: Melanoides tuberculata > Melanopsis praemorsa > Theodoxus jordani. Although there

Khaled M. Swaileh; Mohamed N. Mesmar; Naim S. Ismail

1994-01-01

95

Experimental life cycle of Philophthalmus gralli (Trematoda: Philophthalmidae) in Venezuela  

Microsoft Academic Search

Descriptions of the miracidium, mother redia, daughter redia, grandaughter redia, cercaria, metacer- caria and adult stages of Philophthalmus gralli Mathis and Leger,1910 recovered from experimental infections are presented. The intermediate host, Melanoides tuberculata, was collected from freshwater rivulets in Aguasanta and Yaguracual, Sucre State, Venezuela. Chicken were orally infected with cercariae and metacer- cariae, and metacercariae were introduced directly into

Marcos T. Díaz; Luz E. Hernández; Abul K. Bashirullah

96

Biology of the snail-killing fly, Sepedon spangleri Beaver (Diptera: Sciomyzidae). II. Ability of the larvae to kill snails of medical importance in Thailand.  

PubMed

S. spangleri larvae preferred five species of non-operculate snails; Gyraulus convexiusculus Hutton, Segmentina hemisphaerula Benson, Hippeutis umbilicalis Benson, Indoplanorbis exustus Larambergue, and Trochobis trochoideus Benson. They occasionally consumed the operculate snails: Melanoides tuberculata Muller, Lithoglyphopsis aperta, Hubendickia siamensis Brandt, Lacunopis munensis Brandt, Tarebia granifera, Lamarch and Viviparus sp. but were innocuous to Bithynia laevis Lea. PMID:1025750

Sucharit, S; Chandavimol, Y; Sornmani, S

1976-12-01

97

Freshwater snails (Mollusca: Gastropoda) from the Commonwealth of Dominica with a discussion of their roles in the transmission of parasites  

Microsoft Academic Search

We collected six species of freshwater snails from Dominica, including Biomphalaria kuhniana (Clessin, 1883), Gundlachia radiata (Guilding, 1828), Helisoma (=Planorbella) trivolvis (Say, 1817), Melanoides tuberculata (Müller, 1774), Neritina punctulata Lamarck, 1816, and Physa marmorata Guilding, 1828. Our collections indicate that un-reported species such as G. radiata and H. trivolvis are established on Dominica, West Indies. We tested a limited number

Will K. Reeves; Robert T. Dillon; Gregory A. Dasch

2008-01-01

98

Biological control of the snail intermediate hosts of Schistosoma mansoni in Martinique, French West Indies.  

PubMed

In Martinique water-cress beds constituted the last transmission sites for schistosomiasis. The competitor snail, Melanoides tuberculata, was introduced at the beginning of 1983 to a group of water-cress beds and eliminated the snail hosts, Biomphalaria glabrata and B. straminea, in less than two years. Following this first success, M. tuberculata was introduced to the other groups of beds which were inventoried at the beginning of the eighties. At the present time, B. glabrata and B. straminea have totally disappeared from eight sites and only a few individuals have been recorded from 12 sites. The two remaining water-cress beds have dried up and were abandoned. PMID:1519033

Pointier, J P; Guyard, A

1992-06-01

99

Susceptibility of freshwater snails to the amphistome Calicophoron microbothrium and the influence of the species on susceptibility of Bulinus tropicus to Schistosoma haematobium and Schistosoma mattheei infections.  

PubMed

The susceptibility of Bulinus tropicus, B. globosus, Biomphalana pfeifferi, Lymnaea natalensis, and Melanoides tuberculata to Calicophoron microbothrium was examined. Bulinus tropicus had the highest prevalence (65.0%), followed by B. pfeifferi (37.5%), B. globosus (6.8%), and M. tuberculata (5.9%). Lymnaea natalensis was refractory to infection. Bulinus tropicus snails infected with C. microbothrium alone or coinfected with either Schistosoma haematobium or S. mattheei 0, 7, 14, and 21 days after exposure to C. microbothrium produced C. microbothrium cercariae only. PMID:12435124

Chingwena, Givemore; Mukaratirwa, Samson; Kristensen, Thomas K; Chimberi, Moses

2002-10-01

100

Comparative studies on the uptake and effects of cadmium and zinc on the cellular energy allocation of two freshwater gastropods  

Microsoft Academic Search

The uptake and effects of cadmium (Cd) and zinc (Zn) as free metal ions were compared in the freshwater gastropods Melanoides tuberculata and Helisoma duryi. The Langmuir isotherm model was applied to determine the uptake of Cd, Zn, and a mixture of the metals at five different concentrations (Cd: 0.25, 0.51, 0.77, 1.03, 1.29?M; Zn: 0.17, 0.43, 0.86, 2.17, 4.34?M).

L. Moolman; J. H. J. Van Vuren; V. Wepener

2007-01-01

101

Gastrópodes e outros invertebrados do sedimento e associados à macrófita Eichhornia crassipes de um açude hipertrófico do semi-árido paraibano  

Microsoft Academic Search

realizadas coletas bimestrais do sedimento (draga Van Veen, 400cm 2 ) e da planta (puçá com malha de 500µm), no período de julho\\/1998 a novembro\\/1999 e concomitantemente foram medidas as variáveis ambientais. Os gastrópodes destacam-se pela ocorrência e dominância, sendo registradas sete espécies pertencentes a seis famílias distintas. Melanoides tuberculata foi a espécie dominante em ambos os substratos (sedimento e

Francisco José Pegado Abílio; Romualdo Lunguinho Leite; Thiago Leite de Melo Ruffo

102

Experimental life cycle of Philophthalmus gralli (Trematoda: Philophthalmidae) in Venezuela.  

PubMed

Descriptions of the miracidium, mother redia, daughter redia, grandaughter redia, cercaria, metacercaria and adult stages of Philophthalmus gralli Mathis and Leger, 1910 recovered from experimental infections are presented. The intermediate host, Melanoides tuberculata, was collected from freshwater rivulets in Aguasanta and Yaguracual, Sucre State, Venezuela. Chicken were orally infected with cercariae and metacercariae, and metacercariae were introduced directly into the eyes by pipette. Both processes of infection produced adult worms. This is a new geographical record for P. gralli. PMID:12298291

Díaz, Marcos T; Hernández, Luz E; Bashirullah, Abul K

2002-06-01

103

Camouflaged invasion of Lake Malawi by an Oriental gastropod  

Microsoft Academic Search

In this study we report the first animal invasion, to our knowledge, into Lake Malawi. The colonizer is a non-native morph of the gastropod Melanoides tuberculata that differs substantially in external shell characters from co-occurring indigenous forms. However, because the species possesses extensive within-Africa geographical variation in shell morphology, it was unclear whether the invasion was range expansion of a

M. J. Genner; ELLINOR MICHEL; DIRK ERPENBECK; Voogd de N. J; FRANS WITTE; P. Pointier

2004-01-01

104

Freshwater snails in Asser region, Saudi Arabia with special refernce to the zoonotic trematode.  

PubMed

The present study gave information about the recent distribution of freshwater snails in Asser region, and the current status of trematode infection specially schistosomiasis within the snails. Fifteen localities were visited from Septeinber 2007 to December 2008 and the collected snails were examined for the presence of trematode infection. Seven species of snails were collected: Biomphalaria arabica, Bulinus truncatus, Bulinus beccari, Physa acuta, Lymnaea palustris, Lymnaea arabica and Melanoides tuberculata. The parasitological examination revealed none trematode immature stages. PMID:19795761

Bin Dajem, Saad M

2009-08-01

105

Constraints on Pleistocene pluvial climates through stable-isotope analysis of fossil-spring tufas and associated gastropods, Kharga Oasis, Egypt  

Microsoft Academic Search

Stable-isotope analyses of fossil-spring carbonates (tufas) and freshwater gastropods (Melanoides tuberculata) from the currently hyperarid Western Desert of Egypt indicate that this region received enough precipitation to support a small perennial lake during the height of the oxygen-isotope stage 6\\/5e pluvial event, and a substantial volume of spring discharge during prior pluvial phases. Tufa and gastropod oxygen-isotope ratios are generally

Jennifer R Smith; Robert Giegengack; Henry P Schwarcz

2004-01-01

106

Paleohydrology of a Pleistocene Pluvial Lake in the Western Desert of Egypt  

Microsoft Academic Search

Stable isotope and minor element analyses of authigenic calcite silts and gastropods from a small (~3-4 km2) paleolake at Wadi Midauwara in Kharga Oasis provide evidence for the prolonged presence of perennial fresh surface water in the currently hyper-arid Western Desert of Egypt during the ~130 ka pluvial event. While sequential chemical analyses of the freshwater gastropod Melanoides tuberculata provide

J. Kieniewicz; J. R. Smith

2005-01-01

107

Population dynamics of aquatic snails in Pampulha reservoir.  

PubMed

An attempt was made to determine more accurately the density of molluskan populations in the Pampulha reservoir, using the quadrate method, intending to detect the fluctuation of the populations density, the habitat conditions and the possible competitive interactions among Biomphalaria tenagophila, Melanoides tuberculata, Pomacea haustrum and Biomphalaria glabrata, through the analysis of populational parameters. Among the most significative facts observed in the reservoir it has to be mentioned: the almost disappearance of B. glabrata; the invasion, colonization, fixation and fast growing of M. tuberculata population until reaching about 11,000 individuals/m2; the density fluctuations of B. tenagophila, P. haustrum and M. tuberculata alives and deads; differences on the habitat preference of these three molluskan species at the edge (at the limit earth-water, at 0.70m and 1.40m from the shore line); monthly mortality rates and reproduction seasons of the species. PMID:3509186

Freitas, J R; Bedê, L C; De Marco Júnior, P; Rocha, L A; Santos, M B

1987-01-01

108

Effect of six non-target snails on Schistosoma mansoni miracidial host finding and infection of Biomphalaria alexandrina under laboratory conditions.  

PubMed

Six snail species naturally associated with Biomphalaria alexandrina, the snail host of Schistosoma mansoni in Egypt, were tested under standard laboratory conditions, for impact on miracidial host findings and infection of the snail host. These snails are the prosobranchs Melanoides tuberculata, Cleopatra bulimoides, Bellamys unicolor and Lanistes carinatus, the pulmonates Planorbis planorbis and Physa acuta. The tested snail ssp. reduced considerably the infection rate of Biomphalaria with S. mansoni especially at a ratio of 10 decoy snails to one Biomphalaria snail. The prosobranchs Melanoides, Cleopatra and Lanistes exhibited more reducing effect on Biomphalaria infection than Bellamya and the pulmonates Physa and Planorbis being 65.2%, 78.8%, 62.9%, 33.3%, 30.3% and 46.9%, respectively. PMID:9707684

Yousif, F; el-Emam, M; el-Sayed, K

1998-08-01

109

Camouflaged invasion of Lake Malawi by an Oriental gastropod.  

PubMed

In this study we report the first animal invasion, to our knowledge, into Lake Malawi. The colonizer is a non-native morph of the gastropod Melanoides tuberculata that differs substantially in external shell characters from co-occurring indigenous forms. However, because the species possesses extensive within-Africa geographical variation in shell morphology, it was unclear whether the invasion was range expansion of a native African morph, or a colonization from elsewhere. Mitochondrial DNA sequences indicate a southeast Asian origin for the invader, suggesting that shell variation found among indigenous allopatric populations camouflaged an intercontinental invasion. PMID:15245389

Genner, Martin J; Michel, Ellinor; Erpenbeck, Dirk; De Voogd, Nicole; Witte, Frans; Pointier, Jean-Pierre

2004-08-01

110

Occurrence and distribution of fresh-water molluscs in the Riacho Fundo Creek Basin, Brasilia, Brazil.  

PubMed

To study the distribution of molluscs in the Riacho Fundo Creek (cerrado region of central Brazil), five creek sites were sampled once every two months for one year. Molluscs were sampled using standardized kick-net sampling. Four species of molluscs were found: Physella cubensis, Melanoides tuberculata, Biomphalaria straminea and Pisidium sp. The most abundant were P. cubensis and Pisidium sp. Physella cubensis was most abundant in the dry season and Pisidium sp. was most abundant in the rainy season, probably reflecting the rainy season increase of water currents. PMID:12189816

Martins-Silva, M J; Barros, M

111

[Malacological survey of the Soledade lake hydrographic basin, in Ouro Branco (Minas Gerais, Brazil)].  

PubMed

A malacological survey was carried out at the Soledade Lake, in Ouro Branco, State of Minas Gerais, for the period 1986-1991. A total amount of 46,579 mollusks was collected, and among them seven species corresponding to five families could be found, as follows: 39,176 specimens of Biomphalaria tenagophila; 1,296 B. glabrata; 7 Drepanotrema cimex; 2,527 Physa sp; 417 Lymnaea sp; 92 Pomacea hastrum, and 3,064 specimens of Melanoides tuberculata (Melanniidae = Thiaridae) were collected from March/1990 onwards. Four specimens of B. tenagophila were found to be positive for Schistosoma mansoni. PMID:7569611

da Silva, R E; de Melo, A L; Pereira, L H; Frederico, L F

112

Effect of non target snails on some biological of Lymnaea natalensis snails and their infection to Fasciola gigantica.  

PubMed

The influence of non-target freshwater snails (Melanoides tuberculata and Planorbis planorbis) on the capacity of Fasciola egg production F. gigantica miracidia to infect Lymnaea natalensis and their effect on mortality and growth rates showed that the snails exhibited a competitive ability against L. natalensis. The mortality rate existed in mixed cultures with snails was greatly increased, and increased with increase of snails number. The egg production and growth rate were negatively affected by the presence of M. tuberculata and P. planorbis which was more pronounced when snails were at higher ratio lL: 10D. Also, the snails showed significant degree of reduction in infection rate of L. natalensis with F. gigantica miracidia. PMID:17153707

Bakry, Fayez A; Hamdi, Salwa A H

2006-12-01

113

Biological control and invading freshwater snails. A case study.  

PubMed

Introductions of four species of freshwater snails occurred between 1972 and 1996 onto Guadeloupe Island. Two of them, Melanoides tuberculata and Marisa cornuarietis, were subsequently used as biological control agents against Biomphalaria glabrata, the snail intermediate host of intestinal schistosomiasis. In 1996, a general survey was carried out in 134 sites which had already been investigated in 1972. The total number of mollusc species had increased from 19 to 21. Site numbers housing B. glabrata and two other species had strongly declined. This decline may be mainly attributed to a competitive displacement by M. tuberculata and M. cornuarietis as illustrated by several biological control programmes. There were no changes in the remainder of the malacological fauna. PMID:10656149

Pointier, J P; Augustin, D

1999-12-01

114

Diversity and cercarial shedding of malaco fauna collected from water bodies of Ratnagiri district, Maharashtra.  

PubMed

An investigation on the occurrence of snails in the water bodies of five selected sites i.e., Khed, Chiplun, Ratnagiri, Parchuri and Gimvi of district Ratnagiri, Maharashtra (India) was made during April-May 2006. The study revealed occurrence of nine species of snails viz., Indoplanorbis exustus, Lymnaea luteola, L. acuminata, Paludomus obesus, Ferrissia tenuis, Thiara (Melanoides) tuberculata, Bellamya bengalensis, B. dissimilis and Pila globosa, besides some species of bivalves. I. exustus was the most common species by occurrence in all the selected localities and next to it was L. luteola followed by T. tuberculata, B. bengalensis and B. dissimilis, in succession. Infection with liverfluke and amphistome cercariae was found in most of the collected snail species except P. globosa. However, the Schistosome infection has been reported only in I. exustus and L. luteola. The rice fields, streams and riverbeds shared most abundance of snails whereas those collected from rice fields shedded highest number of cercariae. PMID:18199419

Devi, N Pemola; Jauhari, R K

2007-12-08

115

Linking calcification by exotic snails to stream inorganic carbon cycling.  

PubMed

Biotic calcification is rarely considered in freshwater C budgets, despite calculations suggesting that calcifying animals can alter inorganic C cycling. Most studies that have quantified biocalcification in aquatic ecosystems have not directly linked CO(2) fluxes from biocalcification with whole-ecosystem rates of inorganic C cycling. The freshwater snail, Melanoides tuberculata, has achieved a high abundance and 37.4 g biomass m(-2) after invading Kelly Warm Springs in Grand Teton National Park. This high biomass suggests that introduced populations of Melanoides may alter ecosystem processes. We measured Melanoides growth rates and biomass to calculate the production of biomass, shell mass, and CO(2). We compared Melanoides biomass and inorganic C production with ecosystem C pools and fluxes, as well as with published rates of CO(2) production by other calcifying organisms. Melanoides calcification in Kelly Warm Springs produced 12.1 mmol CO(2) m(-2) day(-1) during summer months. We measured high rates of gross primary productivity and respiration in Kelly Warm Springs (-378 and 533 mmol CO(2) m(-2) day(-1), respectively); CO(2) produced from biocalcification increased net CO(2) production in Kelly Warm Springs from 155 to 167 mmol CO(2) m(-2) day(-1). This rate of CO(2) production via biocalcification is within the published range of calcification by animals. But these CO(2) fluxes are small when compared to ecosystem C fluxes from stream metabolism. The influence of animals is relative to ecosystem processes, and should always be compared with ecosystem fluxes to quantify the importance of a specific animal in its environment. PMID:20058027

Hotchkiss, Erin R; Hall, Robert O

2010-01-08

116

Ecotoxicological effect characterisation of widely used organic UV filters.  

PubMed

Chemical UV filters are used in sun protection and personal care products in order to protect consumers from skin cancer induced by ultraviolet (UV) radiation. The present study aims to evaluate the effects of three common UV filters butyl-methoxydibenzoylmethane (B-MDM) ethylhexyl-methoxycinnamate (EHMC) and octocrylene (OCR) on aquatic organism, focussing particularly on infaunal and epibentic invertebrates (Chironomus riparius, Lumbriculus variegatus, Melanoides tuberculata and Potamopyrgus antipodarum). Due to their life habits, these organism are especially affected by lipophilic substances. Additionally, two direct sediment contact assays utilising zebra fish (Danio rerio) embryos and bacteria (Arthrobacter globiformis) were conducted. EHMC caused a toxic effect on reproduction in both snails with lowest observed effect concentrations (LOEC) of 0.4 mg/kg (Potamopyrgus antipodarum) and 10 mg/kg (Melanoides tuberculata). At high concentrations sublethal effects could be observed for D. rerio after exposure to EHMC (NOEC 100 mg/kg). B-MDM and OCR showed no effects on any of the tested organism. PMID:22325435

Kaiser, D; Sieratowicz, A; Zielke, H; Oetken, M; Hollert, H; Oehlmann, J

2012-01-11

117

Clonal diversity driven by parasitism in a freshwater snail.  

PubMed

One explanation for the widespread abundance of sexual reproduction is the advantage that genetically diverse sexual lineages have under strong pressure from virulent coevolving parasites. Such parasites are believed to track common asexual host genotypes, resulting in negative frequency-dependent selection that counterbalances the population growth-rate advantage of asexuals in comparison with sexuals. In the face of genetically diverse asexual lineages, this advantage of sexual reproduction might be eroded, and instead sexual populations would be replaced by diverse assemblages of clonal lineages. We investigated whether parasite-mediated selection promotes clonal diversity in 22 natural populations of the freshwater snail Melanoides tuberculata. We found that infection prevalence explains the observed variation in the clonal diversity of M. tuberculata populations, whereas no such relationship was found between infection prevalence and male frequency. Clonal diversity and male frequency were independent of snail population density. Incorporating ecological factors such as presence/absence of fish, habitat geography and habitat type did not improve the predictive power of regression models. Approximately 11% of the clonal snail genotypes were shared among 2-4 populations, creating a web of 17 interconnected populations. Taken together, our study suggests that parasite-mediated selection coupled with host dispersal ecology promotes clonal diversity. This, in return, may erode the advantage of sexual reproduction in M. tuberculata populations. PMID:24118641

Dagan, Y; Liljeroos, K; Jokela, J; Ben-Ami, F

2013-10-01

118

Different learning paradigms for the classification of melanoid skin lesions using wavelets.  

PubMed

We use the wavelet-based decomposition to generate the multiresolution representation of dermatoscopic images of potentially malignant pigmented lesions. Three different machine learning methods are experimentally applied, namely neural networks, support vector machines, and Attributional Calculus. The obtained results confirm that neighborhood properties of pixels in dermatoscopic images are a sensitive probe of the melanoma progression and together with the selected machine learning methods may be an important diagnostic tool. PMID:18002660

Surowka, Grzegorz; Grzesiak-Kopec, Katarzyna

2007-01-01

119

Schistosomiasis on the Entebbe Peninsula.  

PubMed

A comparative study of the prevalence of Schistosoma mansoni and their intermediate host in the fishing villages of Nakiwogo and Kigungu is reported. A total of 520 inhabitants from the two villages were examined for Schistosoma mansoni. Their age varied from 4 to 40 and the infection was found to be higher at Nakiwogo 95(36.6%) than at Kigungu 40(15.4%). The snails collected were 1,345 Biomphalaria choanomphala, 237 Biomphalaria pfeifferi, 180 Bulinus (Bulinus) tropicus, 56 Bulinus (physopsis) globosus and other snails of non-medical importance like Pila ovata, Melanoides tuberculata and Bellamya species. Biomphalaria choanomphala was found to be the major intermediate host for Schistosoma mansoni in the two villages. The intermediate hosts for S. mansoni were screened for cercarial shedding, 2 Biomphalaria pfeifferi shed furcocercous cercariae and 9 Leptocercous cercariae while Biomphalaria choanomphala were an negative. The water contact activities related to infection in the two villages are discussed. PMID:2112995

Lakwo, T L; Odongo-Aginya, E I

1990-01-01

120

Prevalence of Haplorchis taichui in field-collected snails: a molecular approach.  

PubMed

The prevalence of the cercarial stage of an intestinal trematode, Haplorchis taichui, in thiarid snails (Gastropoda: Thiaridae) was investigated using light microscope and species-specific PCR procedures. A total of 988 snails were collected from Mae Taeng district, Chiang Mai province, northern Thailand, which comprised of 3 species; Melanoides tuberculata, Tarebia granifera, and Thiara scabra. The overall prevalence of pleurolophocercous cercariae was 21.7% as determined by the morphology. For genetic detection of H. taichui infection in snails, 2 primers Hapt_F (5'-GGCCAACGCAATCGTCATCC-3') and Hapt_R (5'-GCGTCGGGTTTCAGACATGG-3'), were used. The genomic DNA of H. taichui, which was used as a positive control, gave an amplification of the 256 bp fragment. The overall prevalence of H. taichui from specific PCR was 9.7%. The proportion of H. taichui among the pleurolophocercous cercariae in this study was 44.9%. PMID:21234240

Chontananarth, Thapana; Wongsawad, Chalobol

2010-12-16

121

Haplorchis infections in intermediate hosts from a clonorchiasis endemic area in Meinung, Taiwan, Republic of China.  

PubMed

Snails and freshwater fish were examined from four ponds in the Meinung township in which Clonorchis sinensis was known to be endemic 18 years ago. No metacercariae were found in 478 Tilapia nilotica, whereas of 451 Ctenopharyngodon idellus examined, 16.2%, 3.3% and 0.9% were found to be infected with Haplorchis pumilio, H. taichui and Clonorchis sinensis, respectively. In addition, there were some unidentified metacercariae in 12.0% of Ctenopharyngodon idellus examined. Overall, no positive correlation between infection rates and sizes of infected fish was shown. Six species of snails were collected in this survey and two frequently-occurring snails, Melanoides tuberculata and Thiara granifera were commonly infected with H. pumilio. Reasons for the prevalence of Haplorchis species and the absence of Clonorchis sinensis in fish and snail hosts in a previously reported endemic area for human clonorchiasis are discussed. PMID:12015833

Wang, Jiun-Jye; Chung, Lee-Yii; Lee, June-Der; Chang, Eddy-Essen; Chen, Eng-Rin; Chao, David; Yen, Chuan-Min

2002-06-01

122

First report of a field outbreak of the oriental eye-fluke, Philophthalmus gralli (Mathis & Leger 1910), in commercially reared ostriches (Struthio camelus) in Zimbabwe.  

PubMed

A total of 17 commercially reared ostriches (Struthio camelus) from Msengi farm, Chinhoyi, Zimbabwe, observed with swollen eyes, severe conjunctivitis and constant lacrimation accompanied by a purulent exudate, were restrained for further clinical examination. Some of the birds were semi-blind with severe loss of body condition. When examined, tiny organisms were observed attached to the nictitating membranes and the conjuctival sacs of both eyes. The organisms were identified as Philophthalmus gralli, the "oriental eye-fluke" and Melanoides tuberculata, a prosobranch snail, was confirmed as the intermediate host through natural and experimental infection. To the best of our knowledge this is the first record of the oriental eye-fluke infection in birds in Zimbabwe and Africa and extends its known geographical range. PMID:16300188

Mukaratirwa, S; Hove, Thokozani; Cindzi, Z M; Maononga, D B; Taruvinga, M; Matenga, Elizabeth

2005-09-01

123

Prevalence of Haplorchis taichui in Field-Collected Snails: A Molecular Approach  

PubMed Central

The prevalence of the cercarial stage of an intestinal trematode, Haplorchis taichui, in thiarid snails (Gastropoda: Thiaridae) was investigated using light microscope and species-specific PCR procedures. A total of 988 snails were collected from Mae Taeng district, Chiang Mai province, northern Thailand, which comprised of 3 species; Melanoides tuberculata, Tarebia granifera, and Thiara scabra. The overall prevalence of pleurolophocercous cercariae was 21.7% as determined by the morphology. For genetic detection of H. taichui infection in snails, 2 primers Hapt_F (5'-GGCCAACGCAATCGTCATCC-3') and Hapt_R (5'-GCGTCGGGTTTCAGACATGG-3'), were used. The genomic DNA of H. taichui, which was used as a positive control, gave an amplification of the 256 bp fragment. The overall prevalence of H. taichui from specific PCR was 9.7%. The proportion of H. taichui among the pleurolophocercous cercariae in this study was 44.9%.

Chontananarth, Thapana

2010-01-01

124

Susceptibility of Iraqi fresh water snails to infection with Schistosoma haematobium and Schistosoma mansoni Egyptian strains.  

PubMed

A great number of Egyptian workers and farmers are seeking settlement in Iraq and some of them proved to have either Schistosoma Haematobium (S.h.) or Schistosoma mansoni (S.m) or even mixed infection. Besides, there is the possibility that some of the Iraqi fresh water snails may prove to be susceptible to infection by one or both of the Schistosoma Egyptian strains. The present study deals with investigations on the susceptibility of Iraqi B. truncatus, Gyranaulus ehrenbergi, Physa c.f. fontinalis, Lymnea lagetis, Melanoides tuberculata and Melanopsis nodes by these parasites. Egyptian S. haematobium but not Egyptian S. mansoni infect Iraqi B. truncatus and both proved to be unable to infect any of the other snails included in the study. Yet, the number of cercariae shedded by B. truncatus snails infected with the Egyptian S. haematobium strain, was much less that the number of cercariae shedded by these snails when infected with the Iraqi S. Haematobium strain. PMID:555668

Wajdi, N A; Hussain, W I; El-Hawary, M F

1979-01-01

125

Freshwater mollusks of medical importance in Kalasin Province, northeast Thailand.  

PubMed

A snail survey was performed in six districts around irrigation areas of Lampao Dam, in Kalasin Province. The survey caught a total of 5,479 live snails and classed them into five families, 12 genera and 15 species, of which 7 species are suspected of transmitting human parasitic diseases. The seven species were Pila polita, Pomacea canaliculata, Filopaludina (S.) m. martensi, Bithynia (Digoniostoma) siamensis goniomphalos, Melanoides tuberculata, Radix rubiginosa, and Indoplanorbis exustus. Of these, B. (D.) s. goniomphalos and I. exustus were found to harbor emergent cercariae. Only B. (D.) s. goniomphalos hosted several types of cercariae--Opisthorchis viverrini, unidentified species of intestinal flukes, echinostomes, xyphidio and furcocercous cercariae. Indoplanorbis exustus shed only echinostome cercariae. B. (D.) s. goniomphalos showed a rather high natural infection rate with O. viverrini, 1.3% in Yang Talat district, and 0.61% in Kamalasai district, in Kalasin Province. PMID:16124433

Sri-Aroon, Pusadee; Butraporn, Piyarat; Limsomboon, Jaremate; Kerdpuech, Yupa; Kaewpoolsri, Manus; Kiatsiri, Songtham

2005-05-01

126

Effect of water plants and non-target snails on the infectivity of Bulinus truncatus with Schistosoma haematobium.  

PubMed

The application of the water plant (Ceratophyllum demersum, Eichhornia crassipes and Lemna gibba) and/or non-target snails (Planorbis planorbis, Physa acuta and Melanoides tuberculata) gave a significant degree of reduction in the infection rate of B. truncatus subjected to S. haematobium miracidia. The data also indicated a reduction in mean total number of cercarial production/snail. However, no significant difference was detected in the prepatent period and duration of cercarial shedding of the parasite when compared with the control group. So, the results revealed that the snails exhibited a competitive ability against B. truncatus. Both survival rate and egg production of B. truncatus were greatly reduced when existed in mixed cultures with non-target snails and the magnitude of this reduction increased by increasing the number of the non-target snails. PMID:16333895

Bakry, Fayez A; Abd-el-Monem, Sayed

2005-12-01

127

Studies on the morphology of cercariae obtained from freshwater snails at Erawan Waterfall, Erawan National Park, Thailand.  

PubMed

The morphology of cercariae of freshwater snails from Erawan Waterfall, Erawan National Park, Kanchanaburi Province was studied between December 2002 and August 2003. The snail samples were collected by handpicking using a counts per unit of time sampling method. The cercariae, larva stage of a trematode, were investigated using the shedding method where they were categorized into three groups and six species. The first group, Pleurolophocercous cercariae, consists of Haplorchis pumillo (C1) and Stictodora tridactyla (C3). The second group, Furcocercous cercariae, consisted of Mesostephanus appendicalatus (C2), Transversotrema laruei (C6) and Cardicola alseae(C4). The third group, Xiphidio cercariae, has only one species which is Loxogenoides bicolor (C5). Out of 1163 snails, only 62 were found to be infected by cercariae, equivalent to a 5.33% infection rate. The infections grouped by species of the cercariae are as follows: C, 22 (1.9%), C, 29 (2.5%), C2 1 (0.1%), C6 1 (0.1%), C4 6 (0.5%) and C5 3 (0.3%). The freshwater snail samples consist of four species. From a total of 1163 samples, there are 687 Melanoides jugicostis, 91 Tarebia granifera, 296 Thiara scabra and 89 Melanoides tuberculata. Infections were found in 45 (6.5%), 6 (6.6%), 1 (0.3%) and 10 (11.2%), respectively. PMID:17539280

Ukong, Suluck; Krailas, Duangduen; Dangprasert, Tunyarut; Channgarm, Pasapong

2007-03-01

128

A molecular phylogeography approach to biological invasions of the New World by parthenogenetic Thiarid snails.  

PubMed

The parthenogenetic snail Melanoides tuberculata, present in tropical fresh waters of most of the Old World before 1950, has now invaded the Neotropical area. The phylogeography of this snail was studied to evaluate the pathways and number of such invasions. Because of parthenogenetic reproduction, individuals are structured into genetical clones. Within populations from both the original and invaded areas, several morphologically distinct clones (referred to as morphs) often coexist but the amount of genetic divergence among morphs is unknown. Individuals from 27 morphs and 40 populations world-wide were sequenced at two mitochondrial genes (12S and 16S). Our phylogenetic reconstruction suggests that (i) most of the morphological variation observed in the New World predates invasion, (ii) at least six independent introductions have occurred, and (iii) invasive clones are found throughout most of the phylogenetic tree and do not come from a particular region of the area of origin. Two ideas are discussed in the light of these results. The first lies with the specificities of parthenogenesis in an invasion context. While in sexual species, independently introduced populations eventually merge into a single invasive population, in a parthenogenetic species independently introduced clones have distinct invasion dynamics and possibly exclude each other. Second, although repeated invasions in Melanoides may have an impact on indigenous molluscan faunas, their most likely effect is the world-wide homogenization of the invasive taxon itself. PMID:14629383

Facon, B; Pointier, J-P; Glaubrecht, M; Poux, C; Jarne, P; David, P

2003-11-01

129

Elimination of Biomphalaria pfeifferi, Bulinus tropicus and Lymnaea natalensis by the ampullarid snail, Marisa cornuarietis, in a man-made dam in northern Tanzania.  

PubMed

Marisa cornuarietis is a well known ampullarid competitor/predator of Biomphalaria glabrata in Puerto Rico. For the first time in Africa a flourishing population of Marisa has been established in a small, permanent, man-made dam at Kisangara, near Moshi, Tanzania. Prior to the release of M. cornuarietis in June 1977, this dam supported thriving populations of the pulmonate snail hosts Biomphalaria pfeifferi and Lymnaea natalensis; Bulinus tropicus and the melaniid Melanoides tuberculata were also common. Some 24 months after the establishment of Marisa the three pulmonate species had been eliminated; only M. tuberculata remained at about the same population density as originally recorded. Marisa has not caused any obvious adverse environmental impact in the dam. There is at present no valid evidence that this ampullarid would be a threat to local rice production, which is the only crop at risk, but carefully designed field trials should be undertaken to confirm or refute this view. In view of the vast number of permanent, lentic habitats throughout the Afrotropical region, which act as important transmission sites of schistosomiasis and fascioliasis, the role of Marisa cornuarietis as a cost-effective biological control agent in integrated control operations deserves henceforth to be energetically explored. PMID:6122367

Nguma, J F; McCullough, F S; Masha, E

1982-03-01

130

Assessment of the potential of competitor snails and African catfish (Clarias gariepinus) as biocontrol agents against snail hosts transmitting schistosomiasis.  

PubMed

The objective of this study was to assess the potential of the snails Physa acuta and Melanoides tuberculata and the African catfish Clarias gariepinus as biological control agents against the Schistosoma mansoni intermediate host Biomphalaria pfeifferi under laboratory conditions. Groups of five target and five competitor snails were raised together in experimental aquaria and same number in separate aquaria as controls. Shell size, number of eggs and mortality rate were recorded for twelve consecutive weeks. The stocking density for C. gariepinus was one fish per aquarium. Fish were provided with adequate or inadequate supplementary food and fifteen B. pfeifferi were added to each aquarium. The snails and their eggs were counted daily. Significant differences in shell growth and fecundity were noted between B. pfeifferi and M. tuberculata. Physa acuta was noted to be voracious in food consumption. Snail consumption was faster by fish provided with inadequate supplementary food. Based on the present findings, it is suggested that the two competitor snails and African catfish could be used as biological control agents against B. pfeifferi. Nevertheless, the susceptibility of the competitor snails to other trematodes in Ethiopia must first be ruled out before introducing these snails into new habitats. Follow-up field observation and rigorous laboratory studies remain areas for further research. PMID:18582914

Gashaw, Fikru; Erko, Berhanu; Teklehaymanot, Tilahun; Habtesellasie, Redeat

2008-06-25

131

Current advances on the study of snail-snail interactions, with special emphasis on competition process.  

PubMed

Field work research on population dynamic of snails from the regions of Belo Horizonte and Lagoa Santa give much information about interactions among two or more species of mollusks: Pomacea haustrum, Biomphalaria glabrata, B. tenagophila, B. straminea and Melanoides tuberculata. Data ranging from two years to several decades ago suggest that the Pampulha reservoir is like a cemetery of B. glabrata and B. straminea, species that coexist for more than 14 years in a small part of a stream, whereas only B. glabrata lives in all the streams of the basin. In the last ten to twenty years B. tenagophila has coexisted with P. haustrum and M. tuberculata in the Serra Verde ponds and in the Pampulha dam. However these species have not settled in any of the brooks, except temporarily. The data suggest that the kind of biotope and the habitat conditions are decisive factors for the permanence of each species in its preferencial biotope. B. glabrata, natural from streams and riverheads, quickly disappears from the reservoirs and ponds where it coexists with other species for a short time, independently of the competitive process. Competition needs to be better studied, since in Central America and Caribean islands this kind of study has favored the biological control of planorbid species. PMID:8531669

de Freitas, J R; dos Santos, M B

132

Paragonimiasis in KwaZulu-Natal province, South Africa.  

PubMed

Nine cases of paragonimiasis have been reported from cats (4), dogs (2) and children (3) in South Africa, with an additional suspected case in an adult female patient. Details of these cases are reviewed. All nine cases, and perhaps the adult case as well, were from the province of KwaZulu-Natal but locality data are only available for six of them. These six cases represent four localities which all lie below 100 m above sea level in the province's lowlands, suggesting that there may be a focus of transmission here. The molluscan first intermediate host must be one of the two prosobranch snail species present in the area, Melanoides tuberculata or Tomichia natalensis, and the decapod second intermediate host the common river crab Potamonautes sidneyi. All infected cats and dogs had pulmonary infections, while two human cases for which there is sufficient information had extrapulmonary infections. Transmission appears to be ongoing but the invasive snail Tarebia granifera may be competing with both M. tuberculata and T. natalensis. If so, this may bring transmission to an end. PMID:23253517

Appleton, C C

2012-12-20

133

Susceptibility of 7 freshwater gastropod species in Zimbabwe to infection with Gastrodiscus aegyptiacus (Cobbold, 1876) Looss, 1896.  

PubMed

Gastrodiscosis outbreaks due to Gastrodiscus aegyptiacus were recorded in horses in the vicinity of Harare, Zimbabwe, in the absence of Bulinus forskalii, B. senegalensis and Cleopatra sp. which are considered to be the only intermediate host snails. This suggested the possibility of other snail species acting as intermediate hosts in the life cycle of the trematode. A study was carried out to determine the susceptibility of 7 freshwater snail species to infection with G. aegyptiacus. First generation (F-1) of 5 freshwater pulmonate snail species, Bulinus tropicus, Bulinus globosus, Biomphalaria pfeifferi, Helisoma dyuri and Physa acuta that were bred in the laboratory, and 2 prosobranch snail species, Melanoides tuberculata and Cleopatra sp. that were collected from the field were used in this study. Data pertaining to mortalities and cercariae shedding were recorded throughout the experimental period. The prosobranch snails, M. tuberculata and Cleopatra sp. were susceptible to G. aegyptiacus with a minimum prepatent period of 45 days and 54 days, respectively. Bulinus tropicus, P. acuta and H. duryi were susceptible as evidenced by the presence of different generations of rediae and mature cercariae on dissection at 59 days post-infection although attempts to induce the snails to shed from 28 days post-infection did not produce cercariae. Bulinus globosus and Bio. pfeifferi were refractory to infection. The results revealed the ability of G. aegyptiacus to infect M. tuberculata, Cleopatara sp., B. tropicus, P. acuta and H. duryi under experimental conditions and this may explain the recorded outbreaks of gastrodiscosis in equine populations in Zimbabwe in the absence of the known intermediate hosts. Bulinus tropicus is considered as the most likely major intermediate host of G. aegyptiacus because of its wide distribution in Zimbabwe and is well adapted to a wide variety of environments. PMID:15830604

Mukaratirwa, S; Munjere, I F; Takawira, M; Chingwena, G

2004-12-01

134

Biological control of the snail hosts of Schistosoma mansoni in the Caribbean area using Thiara spp.  

PubMed

Field observations and experiments using thiarid snails as competitors of Biomphalaria spp., potential intermediate hosts of Schistosoma mansoni in the Caribbean area, are reviewed. The parthenogenetic snails, Thiara granifera and T. (= Melanoides) tuberculata, were introduced to the Neotropical area in recent decades. In numerous islands and countries, these oriental species have demonstrated their capacity to colonize rapidly and densely many types of habitats while at the same time reducing and even eliminating populations of Biomphalaria spp. The results of field experiments, carried out in several Caribbean islands, have shown the efficiency as well as the limitations of T. tuberculata as a competitor of B. glabrata and B. straminea. In St. Lucia, B. glabrata was apparently eliminated from marshes and streams, 6 to 22 months after the introduction of the competitor. In Martinique, T. tuberculata was introduced into two groups of water-cress beds which constituted the last transmission sites of schistosomiasis on the island. In just less than three years after the introduction of the competitor, both B. glabrata and B. straminea have been eliminated from the transmission sites. In Guadeloupe, several introductions have been carried out in different types of habitat such as permanent ponds, canals, streams and temporary marshes. The findings of all field experiments have indicated that thiarid snails as competitors of pulmonates are favoured by the presence of permanent and stable habitats, preferably shallow, with emergent plants and well oxygenated. On the other hand, the competitor snails are at a disadvantage in waterbodies which are temporary, extremely deep, poorly oxygenated or with a dense mat of floating aquatic vegetation.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2566267

Pointier, J P; McCullough, F

1989-05-01

135

Invading freshwater snails and biological control in Martinique Island, French West Indies.  

PubMed

Eight alien freshwater snail species were introduced into Martinique Island during the last 50 years. The introduced snails include four planorbids (Biomphalaria straminea, Helisoma duryi, Amerianna carinata and Gyraulus sp.), three thiarids (Melanoides tuberculata, M. amabilis and Tarebia granifera) and one ampullarid (Marisa cornuarietis). Four of these species rapidly colonized the whole Martinican hydrographic system whereas the other four remained restricted to some particular sites. The invasion processes were documented during the last 20 years and showed (i) a rapid invasion of the island by several morphs of M. tuberculata at the beginning of the 80's; (ii) the introduction of T. granifera in 1991 and M. amabilis in 1997; and (iii) the rapid spread of these last two species throughout the island. In the years following its introduction, M. tuberculata was used in biological control experiments against the snail hosts of schistosomiasis, B. glabrata and B. straminea. Experiments were conducted with success in several groups of water-cress beds which constituted the latest transmission sites for schistosomiasis at the beginning of the 80's. A malacological survey carried out in 2000 all over the island showed the absence of B. glabrata but the presence of some residual populations of B. straminea. Long-term studies carried out in Martinique have shown that the thiarids are able to maintain relatively stable populations over a long period of time, thus preventing recolonization by the snail hosts. Within this context the invasion of the hydrographic system of Martinique by thiarid snails has resulted in an efficient and sustainable control of the intermediate hosts of schistosomiasis. PMID:11586428

Pointier, J P

2001-01-01

136

CGRP REGULATES THE ACTIVITY OF MANTLE CELLS AND HEMOCYTES IN ABALONE PRIMARY CELL CULTURES (HALIOTIS TUBERCULATA)  

Microsoft Academic Search

Mollusc shell formation requires calcium (Ca++) and bicarbonate (CO3 - ) ions, transported through the mantle via the hemolymph, and the secretion of an organic matrix that interacts with the mineral ions to form either the aragonite or calcite polymorph of calcium carbonate (CaCO3). The biomineralization process takes place in the extrapallial space, between inner shell and outer mantle epithelium,

STÉPHANIE AUZOUX-BORDENAVE; MARTINE FOUCHEREAU-PERON; MARIE-NOËLLE HELLÉOUET; DOMINIQUE DOUMENC

2007-01-01

137

Trematode infections of the freshwater snail family Thiaridae in the Khek River, Thailand.  

PubMed

The freshwater snail family Thiaridae was studied at five different locations: water sources for the Khek River, Thailand. Snail samples were collected by hand using counts per unit of time sampling method between December 2004 and October 2005. The physico-chemical quality of the water changed with the seasons and affected the sampling areas during both the dry season and the flood season. A total of 9,568 snail samples comprised of 14 species were found. These were 284 Tarebia granifera, 24 Melanoides tuberculata, 86 Thiara scabra, 3,295 Paracrostoma pseudosulcospira pseudosulcospira, 736 P. paludiformis paludiformis, 3,266 P. paludiformis dubiosa, 117 P. morrisoni, 304 Brotia (Brotia) binodosa binodosa, 1,250 B. (Brotia) microsculpta, 146 B. (Senckenbergia) wykoffi, 1 B. (Brotia) pagodula, 5 B. (Brotia) binodosa spiralis, 5 B. (Brotia) insolita and 49 B. (Brotia) manningi. The cercariae were investigated using shedding and crushing methods where they were categorized into two types and five species. The first type, Parapleurolophocercous cercariae, were comprised of Haplorchis pumilio Looss, 1899 and Centrocestus formosanus Nishigori, 1924. The second type, Xiphidiocercariae were comprised of Acanthatrium hitaense Koga, 1953, Loxogenoides bicolor Kaw, 1945 and Haematoloechus similis Looss, 1899. The cercarial infection rates in the above 5 species were 0.1% (5:9,568), 0.2% (15:9,568), 0.3% (24:9,568), 0.4% (37:9,568) and 0.1% (5:9,568), respectively. Five species of snails were susceptible to trematode infections. They were T. granifera, M. tuberculata, T. scabra, P. paludiformis paludiformis and B. (Senckenbergia) wykoffi; infections were found in 26.1% (74:284), 33.3% (8:24), 1.2% (1:86), 0.3% (2:736) and 0.7% (1:146), respectively. PMID:18613543

Dechruksa, Wivitchuta; Krailas, Duangduen; Ukong, Suluck; Inkapatanakul, Wasin; Koonchornboon, Tunyarut

2007-11-01

138

Biological control of the snail hosts of schistosomiasis in areas of low transmission: the example of the Caribbean area.  

PubMed

The biological control of schistosomiasis has already proven its efficiency in several habitats in the Caribbean area. Two main types of biological control agents, either trematode parasites or competitor snails have been studied and tested against the snail hosts of schistosomiasis in this region. The first one, Ribeiroia guadeloupensis, a trematode sterilizing Biomphalaria glabrata was successfully tested in a Guadeloupean pond housing a natural population of B. glabrata. The second agent involves several species of competitor snails belonging to the Ampullariidae (Pomacea glauca, Marisa cornuarietis) and Thiaridae (Tarebia granifera, Melanoides tuberculata) families. Ampullarid snails were tested with success in several West Indian islands such as Guadeloupe. Thiarid snails have also proven their efficiency but also their limits in several types of habitats in Guadeloupe, Martinique, St. Lucia and Venezuela. Competitor snails have also proven to be useful in preventing the recolonization by the snail hosts after molluscicide treatments. The case of the rivers of the littoral central part of Venezuela is particularly relevant to this issue. The island of Martinique also constitutes a good example of the importance of competitor snails in a post-transmission phase of schistosomiasis control. This island is a well-developed country where schistosomiasis transmission was interrupted in the 1970s. However, the reactivation of some transmission sites was observed in the 1980s. The introduction of M. tuberculata into these sites resulted in the interruption of transmission and the near total disappearance of the snail hosts. Presently, the thiarid snails have colonized the whole Martinican hydrographic system and maintain dense populations preventing an eventual recolonization by the planorbid snails and thus are maintaining a sustainable control. PMID:10996120

Pointier, J P; Jourdane, J

2000-10-23

139

Accumulation of heavy metals in freshwater molluscs.  

PubMed

Heavy metals in the aquatic environment have to date come mainly from naturally occurring geochemical materials. However, this has been enhanced by human activity such as gold mining in the case of heavy metal pollution in Sg Sarawak Kanan. The high suspended solid loads in the river have quite efficiently removed most soluble metals from the water and trapped them in the bottom sediment. Three freshwater mollusc species were collected at the point source of the heavy metal pollutants and analysed for the heavy metal contents in their tissues and shells. Two of the mollusc species (Brotia costula and Melanoides tuberculata) are purely freshwater species while the Clithon sp. nr retropictus is able to survive in fresh and brackish water environments. The Brotia costula and the Clithon sp. are the edible species which are sold in the market. Accumulation of As, Cu, Fe, Se and Zn in all the three mollusc species were determined and the level of As in the tissues of Brotia costula and the Clithon sp. was much higher than the permissible level for human consumption. The mollusc species also demonstrated different preferences for the uptake of different metals. Variations in the heavy metal contents in the shell and tissues of the same species were also observed. PMID:9646520

Lau, S; Mohamed, M; Yen, A T; Su'ut, S

1998-06-18

140

Studies on schistosomiasis in the Niger Delta: Schistosoma intercalatum in the urban city of Port Harcourt, Nigeria.  

PubMed

Ova of S. intercalatum have been found in the urban city of Port Harcourt in the Niger Delta area of Nigeria, following examination of stool and urine samples from 1,709 persons (5-15 years of age) resident in various parts of the city. The ova occurred only in urine, with prevalence ranging from 1.0% to 9.8% with an overall prevalence of 5.7%. The intensity of the infection was low. Most infected individuals had counts of less than 500 ova in total bladder content. There was no significant difference in either the prevalence or intensity of the infection among the sexes (Male; prevalence 6.1%, intensity 527.3 vs Female; prevalence 5.4%, intensity 500.9). No case of infection with either S. haematobium or S. mansoni was encountered in the study. Malacological surveys in the gutters, creeks, streams and stagnant waterbodies within the city showed the presence of Lymnaea natalensis, Bulinus forskalii, Pila ovata, Melanoides tuberculata, Physa sp., Lanistes ovum and Segmentorbis sp. B. forskalii is indicated as the probable vector of S. intercalatum in the city. The growing problem of urban schistosomiasis in tropical Africa is discussed. Further studies on urban transmission and epidemiology of schistosomiasis in the Niger Delta area of Nigeria is also indicated. PMID:2772131

Arene, F O; Ukpeibo, E T; Nwanze, E A

1989-07-01

141

Comparative studies on the uptake and effects of cadmium and zinc on the cellular energy allocation of two freshwater gastropods.  

PubMed

The uptake and effects of cadmium (Cd) and zinc (Zn) as free metal ions were compared in the freshwater gastropods Melanoides tuberculata and Helisoma duryi. The Langmuir isotherm model was applied to determine the uptake of Cd, Zn, and a mixture of the metals at five different concentrations (Cd: 0.25, 0.51, 0.77, 1.03, 1.29 microM; Zn: 0.17, 0.43, 0.86, 2.17, 4.34 microM). The model gave a good description of metal uptake over a short exposure period (6 h). The gastropods showed interspecies differences in the uptake of Zn. The linear uptake of Cd was similar in these species, although the data did not yield a good fit to the model. No clear Cd/Zn interaction was observed with the mixed metal exposures and both species showed a reduced net uptake for the metals. Cellular energy allocation as a biomarker of exposure provided a measure of the net energy budget (total available energy reserves and total energy consumption). The gastropods were exposed to 0.51 microM Cd, 0.43 microM Zn, and mixture of the metals for a 2-week period. Both species elicited similar decreased net energy budgets following the metal exposures. A combined study on metal uptake and biomarker responses in organisms allows the ability to make interspecies sensitivity comparisons in ecotoxicological studies. PMID:17303241

Moolman, L; Van Vuren, J H J; Wepener, V

2007-02-15

142

Pattern of emergence and the effects of temperature and light on the emergence and survival of heterophyid cercariae (Centrocestus formosanus and Haplorchis pumilio).  

PubMed

Production of the cercariae of Centrocestus formosanus and Haplorchis pumilio was not affected by a 10-day starvation of the snail host Melanoides tuberculata, and there was no circadian rhythm in the pattern of cercarial emergence. Daily average cercarial productions from each snail were 1,643 for C. formosanus and 689 for H. pumilio at 25 C and 500 lux illumination. The number of cercariae was moderately correlated with the size of snail host. The heaviest sheddings ever observed from 1 snail in 24 hr were 63,400 cercariae for C. formosanus and 3,470 cercariae for H. pumilio. The cercariae of C. formosanus could emerge in the dark, but the number was much less than in the light. In contrast, the cercariae of H. pumilio emerged equally well with or without light. Within the temperature range tested, the emergence of cercariae occurred at 15-35 C, but not at 10 C. Shedding of C. formosanus cercariae increased with the rise in ambient temperature, whereas the greatest shedding of H. pumilio cercariae occurred at 25 C. Life-span of the cercariae was temperature-dependent. The most favorable temperature for survival of C. formosanus was 15 C, at which some survived for 160 hr, and 20 C for H. pumilio, with the longest survival of 130 hr. PMID:8604114

Lo, C T; Lee, K M

1996-04-01

143

Human urinary schistosomiasis transmission foci and period in an endemic town of Ijebu North, Southwest Nigeria.  

PubMed

Human urinary schistosomiasis transmission foci and period were investigated in an endemic town in Ijebu North, Southwest Nigeria. Three important streams (Areru, Eri-Oru and Ojupon) were sampled using long-handled scoop and a pair of tongs, between September 2002 and October 2003. Out of the 3500 freshwater snails collected, six species were identified which are Lanistes libycus (46.7%), Potadoma moerchii (31.4%), Melanoides tuberculata (1.5%), Bulinus globosus (18.2%), B.forskalii (0.2%) and Afrogyrus coretus (2.1%). 611 (96.1%) of the B.globosus recorded were from Eri-Oru and Areru streams 588 (96.2%) of the B.globosus from these two streams were recorded during little or no rainfall period when the snail infection rate range was 2.3 to 21.0%. Artificial cercarial infection of laboratory mice yielded terminally- spined eggs characteristic of Schistosoma haematobium. 16.2% and 5.0% of A. coretus collected from Eri-Oru in January and March 2003 respectively, shed cercariae which were not furcocercous. The results are discussed in relation to the nutritional significances of L. libycus and P.moerchii, findings from preliminary study and rainfall pattern in the study area. The study showed that human urinary schistosomiasis transmission occurred mainly in the dry season and that Eri-Oru and Areru streams were the main transmission foci. PMID:16493394

Agbolade, O M; Akinboye, D O; Fajebe, O T; Abolade, O M; Adebambo, A A

2004-12-01

144

Deriving freshwater quality criteria for iron, lead, nickel, and zinc for protection of aquatic life in Malaysia.  

PubMed

Freshwater quality criteria for iron (Fe), lead (Pb), nickel (Ni), and zinc (Zn) were developed with particular reference to aquatic biota in Malaysia, and based on USEPA's guidelines. Acute toxicity tests were performed on eight different freshwater domestic species in Malaysia which were Macrobrachium lanchesteri (prawn), two fish: Poecilia reticulata and Rasbora sumatrana, Melanoides tuberculata (snail), Stenocypris major (ostracod), Chironomus javanus (midge larvae), Nais elinguis (annelid), and Duttaphrynus melanostictus (tadpole) to determine 96 h LC(50) values for Fe, Pb, Ni, and Zn. The final acute value (FAV) for Fe, Pb, Ni, and Zn were 74.5, 17.0, 165, and 304.9 ?g L(-1), respectively. Using an estimated acute-to-chronic ratio (ACR) of 8.3, the value for final chronic value (FCV) was derived. Based on FAV and FCV, a criterion maximum concentration (CMC) and a criterion continuous concentration (CCC) for Fe, Pb, Ni, and Zn that are 37.2, 8.5, 82.5, and 152.4 ?g?L(-1) and 9.0, 2.0, 19.9, and 36.7 ?g?L(-1), respectively, were derived. The results of this study provide useful data for deriving national or local water quality criteria for Fe, Pb, Ni, and Zn based on aquatic biota in Malaysia. Based on LC(50) values, this study indicated that N. elinguis, M. lanchesteri, N. elinguis, and R. sumatrana were the most sensitive to Fe, Pb, Ni, and Zn, respectively. PMID:22919358

Shuhaimi-Othman, M; Nadzifah, Y; Nur-Amalina, R; Umirah, N S

2012-08-02

145

Biodiversity assessment of benthic macroinvertebrates along a reservoir cascade in the lower São Francisco river (northeastern Brazil).  

PubMed

In order to verify the cascade-system effect in benthic macroinvertebrate communities, and the implications for policy making and proposals for conservation and sustainable use of the lower portion of São Francisco river basin (Bahia State, Brazil), a three-reservoir cascade system including two stretches downstream were studied during dry (June, 1997) and rainy (March, 1998) periods. The dominant groups found were Mollusca (Melanoides tuberculata), Oligochaeta, and Chironomidae larvae. Low Shannon-Wiener and Pielou index values were found, but with no significant difference between the sampling periods. However, density and taxonomic richness were significantly different (t(0.05: 31)) = -2.1945; p < 0.05; e t(0.05; 31) = -3.0600; p < 0.01) between the sampling periods, with a reduction in the number of taxa and macroinvertebrate abundance during the rainy period. An increasing gradient in benthic macroinvertebrate community structures was noted along the reservoir cascade from the first reservoir (Apolônio Sales), followed by a decrease downstream from the third reservoir of the system (Xing6). Despite the negative consequences of rapid proliferation of dams, which have caused widespread loss of freshwater habitats, the reservoir cascade system promoted an increase in benthic macroinvertebrate diversity, due to water-quality improvement along the system. PMID:16097725

Callisto, M; Goulart, M; Barbosa, F A R; Rocha, O

2005-05-01

146

Trematode infections in freshwater snails and cattle from the Kafue wetlands of Zambia during a period of highest cattle-water contact.  

PubMed

A total of 984 snails, comprising nine species, were collected from six areas in the Kafue wetlands between August and October 2003 to assess larval trematode infections. Of these, 135 (13.7%) were positive. Most trematode infections were recorded from Lymnaea natalensis (42.8%), which harboured four of the five morphologically different cercariae found. No trematodes were recovered from Bellamya capillata, Biomphalaria pfeifferi, Melanoides tuberculata, Physa acuta and Cleopatra nswendweensis. One snail (0.2%) of 416 Bulinus snails shed brevifurcate-apharyngeate distome cercariae while three (0.7%) shed amphistomes. Gymnocephalous and longifurcate-pharyngeate distome were the commonest types of cercariae recorded while xiphidiocercaria was the least common. The highest prevalence rates of F. gigantica (68.8%) and amphistomes (50.0%) in cattle (n = 101) were in Chiyasa while those in Kaleya had the lowest (9.1 and 18.2%, respectively). In most habitats, infections were recorded in both cattle and snails. Critical determinants of infection may have been the distance of settlements and/or cattle kraals, the number of animals in nearby homesteads and the presence of susceptible host snails. This study suggests that fascioliasis and amphistomiasis could be major constraints of cattle production in the Kafue wetlands because favourable factors were available to introduce and maintain the infections. It further provides a starting point for some comprehensive studies on snail-related aspects of transmission and snail host ecology in Zambia. PMID:17381873

Phiri, A M; Phiri, I K; Chota, A; Monrad, J

2007-03-01

147

[Control of intestinal schistosomiasis in Martinique island].  

PubMed

The presence of schistosomiasis mansoni is known in Martinique since the beginning of the XXth century. A general survey of the distribution of the disease was carried out in 1977 and showed a mean prevalence of 12% (coprology and serology taken together) in the whole of the island. Following this survey, an integrated control programme associating sanitary education, detection and treatment of patients and improved sanitation, was developed. In addition, a biological control programme against the intermediate snail host, Biomphalaria glabrata using the competitor snail, Melanoides tuberculata, was developed in the transmission sites. The decline of snail populations and of its parasite, as well as a strong reduction of the prevalence in humans were recorded between 1977 and 1996. At the present time, only few cases corresponding to older infections are detected. This epidemiological situation is quite different from that in Guadeloupe island where, in spite of an excellent control programme which was achieved on the Basse-Terre district, an important focus is still functioning on Grande-Terre district with the black rat as host reservoir. Such foci do not exist on Martinique island. PMID:9587606

Schlegel, L; Pointier, J P; Petitjean-Roget, V; Nadeau, Y; Blateau, A; Mansuy, J M

1997-09-01

148

Predation of Biomphalaria and non-target molluscs by the crayfish Procambarus clarkii: implications for the biological control of schistosomiasis.  

PubMed

The North American crayfish Procambarus clarkii was examined under laboratory conditions for its ability to prey on Biomphalaria pfeifferi and B. glabrata, molluscan intermediate hosts of human schistosomiasis, and other, non-target gastropod species. Both male and female adult crayfish significantly reduced survival of neonate snails, even though alternative animal and plant foods were both available. In subsequent experiments, no differences in snail consumption were detected, for either adult or juvenile crayfish, in the presence or absence of a plant food alternative. Both adult and juvenile crayfish were able to consume small (2.5 mm) and large (17.5 mm) B. glabrata, suggesting that no size refuge from predation exists. Both adult and juvenile crayfish consumed Biomphalaria egg masses, although this consumption was significantly greater for juveniles. Procambarus clarkii adults were unable to consume substantial numbers of the relatively thick-shelled prosobranch snails Pila ovata and Lanistes carinatus. Crayfish did consume a third prosobranch, Melanoides tuberculata, and the pulmonate snail Physa acuta, but at a lower rate relative to consumption of Biomphalaria. Physa acuta, itself of North American origin, responded to the presence of crayfish by rapidly leaving the water and thereby avoided predation. Implications of these results for the biological control of schistosome-transmitting snails in East Africa are discussed. PMID:1304709

Hofkin, B V; Hofinger, D M; Koech, D K; Loker, E S

1992-12-01

149

Activity of Euphorbia splendens var. hislopii N.E.B. (Euphorbiaceae) latex against Lymnaea columella (Say, 1817) (Pulmonata: Lymnaeidae), intermediate host of Fasciola hepatica, Linnaeus, 1758 (Trematoda: Fasciolidae). 2: limited field-testing.  

PubMed

The molluscicidal evaluation of Euphorbia splendens var. hislopii (Crown of thorns) against Lymnaea columella snails, intermediate host of Fasciola hepatica, in irrigation ditches of the Pisciculture Station at Universidade Federal Rural do Rio de Janeiro, was studied under limited field conditions. An aqueous solution of the latex at 5 mg/l was tested in two irrigation ditches (experimental and control ditches), after initial sampling of the snail population present. Twenty-four hours after application of the product, it was verified that 97.4% of free L. columella snails and 100% of snails of the same species captive in cages and used as sentinels at three points equidistant from the application site in the experimental ditch, died. For Biomphalaria tenagophila and Melanoides tuberculata snails, present in the experimental ditch, the mortality was 100%, for the species Pomacea spp. the mortality was 40%. No mortality was verified in the free mollusks, or in the sentinels in the ditch used as control. E. splendens var. hislopii latex is thus an efficient natural molluscicide, which may be used as an alternative control agent against L. columella. PMID:14762529

de Vasconcellos, Mauricio Carvalho; de Amorim, Alziro

2004-01-07

150

[Socio-cultural and ethical factors involved in the diagnosis of schistosomiasis mansoni in an area of low endemicity].  

PubMed

Five annual parasitological surveys and one serological survey, respectively based on the Kato-Katz and free sedimentation methods and the Western blot technique, were conducted in Sumidouro, Rio de Janeiro, Brazil, an endemic county for schistosomiasis. Possible influences of the use of these methodologies on social, cultural, and ethical aspects of the study population were also evaluated. Having the opportunity to choose the different techniques was a conclusive issue influencing participation by the population. Prevalence rates of positive results for stool tests were: 11.6% (1995); 8.8% (1996); 12.2% (1998); 5.9% (1999); and 3.2% (2000). In the period during which the serological survey was performed, the use of laboratory testing in association with analysis of clinical data and available data on transmission and treatment generated a diagnostic procedure termed "coproseroepidemiology". This methodology contributed to significant improvements in the accuracy of measurement of local schistosomiasis prevalence, indicating that epidemiological surveillance could help prevent the recurrence of high prevalence rates. The fact that Biomphalaria glabrata was replaced by Melanoides tuberculata in the main transmission focus contributed to a significant decrease in infection rates. PMID:15692642

Gonçalves, Margareth Maria Lessa; Barreto, Magali Muniz Gonçalves; Maldonado, Arnaldo; Maione, Vanessa Regal; Rey, Luís; Soares, Marisa da Silveira

2005-01-28

151

Ecological and molecular studies on emerging schistosomiasis mansoni in Dhofar Governorate, Sultanate of Oman.  

PubMed

The recent detection of some cases of autochtonous schistosomiasis mansoni in Dhofar, Oman, prompted a search for the transmission sites. The five field surveys we conducted from November 2000 to February 2002 provided ecological data on schistosomiasis in Dhofar. Twenty-eight water bodies situated within 8-160 km from Salalah, the largest city of Dhofar and at altitudes of up to 900 m, were surveyed for freshwater snails. Biomphalaria arabica was found in 15 of them. Three sites (Tibraq, Siginitti and Arazat) had Schistosoma infected snails, the first snails shedding cercariae of this parasite ever collected in Oman. The parasite from Dhofar was analysed by Random Amplified Polymorphic DNA comparisons using 11 primers and 167 polymorphic fragments and had 87-88% similarity with Schistosoma mansoni from Guadeloupe, but only 37-38% similarity with S. rodhaini from Burundi. Thus, it is a strain of S. mansoni. During the November 2000 survey, the prosobranch snail Melanoides tuberculata was associated with B. arabica in 10 of the 13 B. arabica sites. Cercariae from other species of Digenea emerged from five of the B. arabica sites, including the three named above. This paper presents the first finding of S. mansoni in the Dhofar Governorate and represents an initial study of the biology of S. mansoni transmission. This parasite and its cycle need further biological and molecular characterization, and the clarification of its epidemiological status in Dhofar Governorate is an urgent task. PMID:12631319

Moné, Hélène; Mouahid, Gabriel; Shaban, Mahmoud A; Al Jabri, Ali A; Boissier, Jérôme; Ruppel, Andreas; Idris, Mohamed A

2003-03-01

152

Laboratory experiments on snail predation by Sargochromis codringtoni, a candidate for biological control of the snails that transmit schistosomiasis.  

PubMed

The potential efficacy of Sargochromis codringtoni, a species of cichlid fish, in the biological control of snails carrying the Schistosoma spp. infecting man has long been recognized. A laboratory study to produce much-needed data on the malacophagous characteristics of this fish was conducted, to see if field studies on its possible role as a biological agent for snail control in Zimbabwe were likely to be worthwhile. The fish can consume large numbers of snails within a short period: a single fish, provided with trout pellets as an alternative food, not only chose to eat the snails but also consumed > 800 within 3 weeks. Addition of macrophytes to the aquaria used appeared to offer the snails no protection from predation. For fish measuring 15-18 cm in length, there was no size preference among snails measuring up to 12 mm in shell height nor was any species preference observed in experiments involving Bulinus globosus, B. tropicus and Melanoides tuberculata. The fish crushed B. globosus which were > 3.0 mm in shell height in their pharynges but swallowed smaller snails of this species whole. Before field trials are conducted, further laboratory studies, in which field conditions are simulated, should be carried out. PMID:9093434

Chimbari, M J; Madsen, H; Ndamba, J

1997-01-01

153

Distribution patterns and cercarial shedding of Bulinus nasutus and other snails in the Msambweni area, Coast Province, Kenya.  

PubMed

In the Msambweni area of the Kwale District in Kenya, an area endemic for Schistosoma haematobium, potential intermediate-host snails were systematically surveyed in water bodies associated with human contact that were previously surveyed in the 1980s. Bulinus (africanus) nasutus, which accounted for 67% of the snails collected, was the only snail shedding S. haematobium cercariae. Lanistes purpureus was the second most common snail (25%); lower numbers of Bulinus forskalii and Melanoides tuberculata were also recovered. Infection with non-S. haematobium trematodes was found among all snail species. Rainfall was significantly associated with the temporal distribution of all snail species: high numbers of Bulinus nasutus developed after extensive rainfall, followed, in turn, by increased S. haematobium shedding. Spatial distribution of snails was significantly clustered over a range of up to 1 km, with peak clustering observed at a distance of 400 meters. Water lily (Nymphaea spp.) and several aquatic grass species appeared necessary for local colonization by B. nasutus or L. purpureus. PMID:15100463

Kariuki, H Curtis; Clennon, Julie A; Brady, Melinda S; Kitron, Uriel; Sturrock, Robert F; Ouma, John H; Ndzovu, Saidi Tosha Malick; Mungai, Peter; Hoffman, Orit; Hamburger, Joseph; Pellegrini, Cara; Muchiri, Eric M; King, Charles H

2004-04-01

154

Trematode Centrocestus formosanus infection and distribution in ornamental fishes in Mexico.  

PubMed

The aim of this study was to determine the ornamental fish species affected by the metacercariae of the digenean trematode Centrocestus formosanus and its distribution in 48 fish farms in Morelos, central Mexico. The parasite was found to form various numbers of branchial cysts in 11 of the 25 species analyzed. Goldfish Carassius auratus was the most commonly affected species; 20 of 30 farms were positive for this parasite, the fish showing severe clinical signs and having a high mortality rate. For the first time in the region, koi (a variant of common carp Cyprinus carpio), zebrafish Danio rerio, suckermouth catfish Hypostomus plecostomus and blue gourami Trichogaster trichopterus (also known as the threespot gourami) were positive; meanwhile, Mexican tetra Astyanax mexicanus, which had previously been reported positive in other studies in this region, was found to be negative. The parasite was observed in fish from 27 of the 48 farms studied. Ten of 15 municipalities had farms that were positive for the parasite. These results suggest that the distribution of C. formosanus is closely related to the use of water that had been contaminated with the parasite and to the presence of a snail, the red-rimmed melania Melanoides tuberculata. PMID:19485122

Ortega, César; Fajardo, Raúl; Enríquez, Ricardo

2009-03-01

155

Argentophilic structures of the miracidia and cercariae of Philophthalmus distomatosa n. comb. from Israel.  

PubMed

The morphology and patterns of distribution of the argentophilic structures of miracidia and cercariae of Philophthalmus distomatosa n. comb. are described. The epidermal plate arrangement of the vast majority (94.2%) of miracidia studied conformed to the formula 6:8:4:2 = 20. The rest (5.8%) displayed the following patterns of arrangement of epidermal plates: 6:7:4:2 = 19; 6:6:4:2 = 18; and 6:4:4:2 = 16. Twenty papillalike structures were observed on the terebratorium. They were arranged along 1 axis, in 3 groups. Most commonly, 16 papillae were present on the body, located between epidermal plates of the first and second rows. The eye spots were located dorsally, near interepidermal space S1. The numbers, arrangements, and locations of the excretory pores varied. Patterns of distribution of the tegumentary papillae of P. distomatosa n. comb. cercariae are given, including those of the cephalic regions, periacetabular region, and tail. Argentophilic structures of the mentioned larval stages and of other parameters clearly distinguishing between the presently described species and those of P. lucipetus from Israel are summarized. On the basis of comparison of the presently described larval stages and those of other Melanoides tuberculata-associated larval stages of Philophthalmus in Israel and Jordan, the possibility exists that a third species occurs in Israel. PMID:11191898

Dimitrov, V; Kanev, I; Panaiotova, M; Radev, V; Gold, D

2000-12-01

156

Angiostrongylus cantonensis (Nematode: Metastrongyloidea) in molluscs from harbour areas in Brazil.  

PubMed

Angiostrongylus cantonensis is the most common aetiological agent of human eosinophilic meningoencephalitis. Following a report indicating the presence of this parasite in Brazil in 2007, the present study was undertaken to investigate the presence of A. cantonensis in the surrounding Brazilian port areas. In total, 30 ports were investigated and the following molluscs were identified: Achatina fulica, Belocaulus sp., Bradybaena similaris sp., Cyclodontina sp., Helix sp., Leptinaria sp., Melampus sp., Melanoides tuberculata, Phyllocaulis sp., Pomacea sp., Pseudoxychona sp., Rhinus sp., Sarasinula marginata, Streptaxis sp., Subulina octona, Succinea sp., Tomigerus sp., Wayampia sp. and specimens belonging to Limacidae and Orthalicinae. Digestion and sedimentation processes were performed and the sediments were examined. DNA was extracted from the obtained larvae and the internal transcribed spacer region 2 was analysed by polymerase chain reaction-restriction fragment length polymorphism after digestion with the endonuclease ClaI. Of the 30 ports investigated in this study, 11 contained molluscs infected with A. cantonensis larvae. The set of infected species consisted of S. octona, S. marginata, A. fulica and B. similaris. A total of 36.6% of the investigated ports were positive for A. cantonensis, indicating a wide distribution of this worm. It remains uncertain when and how A. cantonensis was introduced into South America. PMID:22990962

Carvalho, Omar Dos Santos; Scholte, Ronaldo Guilherme Carvalho; Mendonça, Cristiane Lafeta Furtado de; Passos, Liana Konovaloff Jannotti; Caldeira, Roberta Lima

2012-09-01

157

Pathology and first report of natural eye infection with the trematode Philophthalmus gralli (Digenea, Philophthalmidae) in Tinamus major (Tinamiformes, Tinamidae), Costa Rica.  

PubMed

The eye-fluke Philophthalmus gralli (Philophthalmidae Looss, 1899) was found in six birds known as great tinamous (Tinamus major) reared in a wild animal shelter located in Alajuela, Costa Rica. The birds presented conjunctival hyperemia, blepharitis, anorexia and weakness. Some of them suffered from unilateral blindness and ocular loss. After morphometric analysis, the specimens showed characteristics compatible with the digenean trematode P. gralli. The clinical signs of infection were resolved by manual removal of the adults, treatment with praziquantel and relocation into an environment without a natural water source. In order to determine if an ongoing cycle of this pathogen was present in the shelter, the habitat of the birds was inspected for the presence of infected intermediate hosts and contaminated water and objects. It was found that the snails Melanoides tuberculata acted as the intermediate host, and reared the infectious stages toward other animals, as shown by the reproduction of ocular philophthalmiasis in chickens artificially infected with excysted metacercaria. Moreover, three out of every ten snails found in the place were infected with rediae of P. gralli, raising the possibility of the dispersion of the parasite into new environments as well as the imminent zoonotic risk. The finding of P. gralli in Costa Rica is the first official report in Central America. PMID:23993998

Rojas, Diana; Soto, Carmen; Rojas, Alicia

2013-08-28

158

Paleohydrology of a Pleistocene Pluvial Lake in the Western Desert of Egypt  

NASA Astrophysics Data System (ADS)

Stable isotope and minor element analyses of authigenic calcite silts and gastropods from a small (~3-4 km2) paleolake at Wadi Midauwara in Kharga Oasis provide evidence for the prolonged presence of perennial fresh surface water in the currently hyper-arid Western Desert of Egypt during the ~130 ka pluvial event. While sequential chemical analyses of the freshwater gastropod Melanoides tuberculata provide a seasonal record of lake water chemistry, analyses of the silts present an integrated centennial- to millennial-scale archive of longer term climatic shifts. Thus, climatic variation can be examined over a variety of temporal scales. Stable isotope analyses of the low-Mg calcite silts imply precipitation in equilibrium with water isotopically equivalent to `fossil' groundwater at Kharga Oasis (~-11‰SMOW), and with a dissolved inorganic carbon reservoir exhibiting little influence of respired carbon (average: -0.5‰PDB). While about 3‰ and 1.5‰ variability occurs in ?{18O and ?13C}, respectively, the isotopes do not covary, suggesting that the lacustrine environment at Wadi Midauwara may have been a hydrologically open system. This is supported by sequential intra-shell stable isotope and minor element analyses of Melanoides tuberculata. Stable isotope variability in ?18O can be accounted for by seasonal changes in water temperature coupled with minor fluctuations in water salinity. The Mg/Ca and Sr/Ca ratios of calcite from the lacustrine silts both decrease upwards through the stratigraphic profile, and weakly covary with the ?18O values for the silts. Mg/Ca and Sr/Ca ratios likely reflect the residence time of the water in the local limestone aquifer, which is driven principally by the amount of local recharge. Thus the decrease probably indicates a gradual decrease in the residence time of local water in the limestone aquifer, and implies increasing rainfall. Surprisingly, the Ba/Ca values for the silts do not covary with the Mg/Ca and Sr/Ca. Because Ba and Sr behave similarly in karstic systems, and are also incorporated similarly into the calcite lattice, the lack of covariance of Ba/Ca with Mg/Ca and Sr/Ca was unexpected. As barite cements are not uncommon in the sandstones of the Nubian aquifer, the Ba/Ca ratio of lacustrine calcite may actually be recording the relative contribution of Ba-rich Nubian aquifer water to a lake that was principally fed by local (Sr- and Mg-rich) limestone aquifers as well as by surficial drainage from limestone-floored watersheds. Wadi Midauwara, like many other foci of spring activity within the Western Desert, is located along a fault which may have provided for artesian discharge from the Nubian aquifer at relatively high elevations above the oasis floor. The climate of the pluvial events of the Sahara has been hypothesized to have been dominated by the Atlantic monsoon, with possible minor input from the Indian Ocean Monsoon. The apparent presence of perennial fresh water at Midauwara is contrary to what would be expected for ponds, fed only by seasonal rainfall. If the Western Desert during the ~130 ka pluvial event received significant summer and winter rains, similar to modern equatorial Africa, the seasonal variation in rainfall source should have been recorded as substantial variation in the ?18O of lake water, a variation which we do not observe. It is more likely, then, that perennial groundwater inflow derived from springs along the Libyan Plateau escarpment, as well as, perhaps, from the Nubian aquifer, maintained the lake.

Kieniewicz, J.; Smith, J. R.

2005-12-01

159

Subtipos de virus del papiloma humano y lesiones intraepiteliales e invasoras de cérvix uterino en mujeres de la provincia de Ciudad Real  

Microsoft Academic Search

SUMMARY Foreword :Th eoncogeni crol eo fhuma nPapillomaviru s(HPV )i nintraepithelia llesion so fth euterin ecerv¡ xha sbee nIargel ydescri- bed .Objective :T odetermin eth edifferen tHP VDN Aan dthe¡ rprevalenc ei npatient swit hcytopatholog¡ca llesions .Material sand Methods: The PAP smears of 6,300 women were diagnosed over a 2-year period. The presence of HPV DNA in all ¡ntraep¡thelial lesions,

A. M. Puig; P. Guerra; C. Martínez; C. MiIIana

2001-01-01

160

Coste-utilidad de la incorporación de las nuevas vacunas antineumocócicas conjugadas al programa de vacunación de la comunidad de Madrid. Impacto sobre la enfermedad neumocócica invasora  

Microsoft Academic Search

IntroductionThe inclusion of conjugate pneumococcal vaccines to the Regional Immunization Program avoids cases, among others, of invasive pneumococcal diseases caused by serotypes of Streptococcus pneumoniae contained in the vaccines.

J. Picazo; C. Méndez; I. Oyagüez; M. A. Casado; P. Guijarro

2010-01-01

161

Diversity of mollusks in the Lam Ta Khong reservoir, Nakhon Ratchasima, Thailand.  

PubMed

Sampling surveys to study the diversity of mollusks in the Lam Ta Khong reservoir, Nakhon Ratchasima Province, northeast Thailand, were carried out in the hot, rainy and cold seasons. The study area was divided into: Area I--the upper part where the Lam Ta Khong river drains; Area II--the mid-section of the reservoir; Area III--behind the dam. Mollusks were collected from four locations on each bank (to the right and left) of each area. Each location was sampled to include 6 cross-sectional stations; in total, 144 stations were sampled. In the deep water, an Ekman dredge was used to collect samples; the scoop or manual method was used at the water's edge. Ten species of snails and four species of clams were found. The dominant species of snails were: Clea helena, Bithynia siamensis goniomphalos and Melanoides tuberculata; clams were dominated by Corbicula sp. The intermediate host of the human blood fluke was not found. The population of most mollusk species increased during the cold season while that of clams and that of some species of snails increased during the rainy season. Clams and operculate snails predominated in Areas II and III. Pulmonate snails were mostly found close to the bank and on aquatic plants especially in Areas I and II. Operculate snails and clams mainly inhabited water 1 to 10 m deep. Two species of edible mollusks were found: Filopaludina martensi martensi and large numbers of Corbicula. Neither shedding light nor digestion with pepsin A revealed any human parasites in the mollusks sampled. PMID:12757219

Tesana, Smarn

2002-12-01

162

Life cycle stages of heterophyid trematodes in Vietnamese freshwater fishes traced by molecular and morphometric methods.  

PubMed

A survey of digenean zoonotic trematodes infecting snails and fishes in a North Vietnamese freshwater fish culture system revealed shedding of three types of parapleurolophocercous cercariae from the snail host Melanoides tuberculata and the presence of metacercariae within the genus Haplorchis (H. pumilio and H. taichui) and Procerovum sp. in tissues of cultured fishes (silver carp, Indian carp and climbing perch). No morphological characters were able to link the different cercariae specifically to any of the metacercariae. Subsequent molecular work including PCR and sequencing of ribosomal DNA (the ITS2 region) in cercariae and metacercariae associated only one type of the cercariae to the recovered H. pumilio metacercariae. Further, full identity (100%) was found with regard to the ITS sequence of adult H. pumilio obtained from the same North Vietnamese region. None of the cercariae showed sequence identities with H. taichui but more than 99% identity was found between one cercaria type and the Procerovum sp. metacercaria. It was indicated that trematode parasites of farmed fishes may originate from sources outside the fish ponds and may be introduced as free-swimming cercariae when pond water is being replenished by river water. Likewise, cercariae from the ponds may not always result in metacercarial infections of the farmed fishes. The present study frames the needs for including molecular techniques as auxiliary tools when conducting ecological studies of cercariae in complex ecosystems. The parasites recorded in the fish ponds are not only known to affect the health of aquacultured fishes but also the documented zoonotic potential of the diagnosed metacercaria calls for alerts regarding human consumption of raw or inadequately processed fish dishes. PMID:19056180

Skov, Jakob; Kania, Per W; Dalsgaard, Anders; Jørgensen, Thomas R; Buchmann, Kurt

2008-10-28

163

Population Structure of an Invasive Parthenogenetic Gastropod in Coastal Lakes and Estuaries of Northern KwaZulu-Natal, South Africa  

PubMed Central

Background Estuaries and coastal lakes receive little attention despite being heavily invaded by non-indigenous invasive species (NIS). In these situations, studies of population dynamics in invaded habitats can provide valuable insights into how NIS interact with new environments. Tarebia granifera is a prosobranch gastropod from south-east Asia which has invaded other sub-tropical parts of the world. This study addresses whether a small number of key environmental factors influences gastropod communities, and specifically how the population density and size structure of T. granifera were influenced by environmental change in estuaries and coastal lakes in southern Africa. Methodology/Principal Findings T. granifera's density, number of brooded juveniles and size structure were measured at the St. Lucia Estuary, Mgobozeleni Estuary, Lake Sibaya and Lake Nhlange. Size structure was classified according to shell height (SH). All dissected individuals were found to be female and free from trematode infection. Salinity, water depth, temperature, and pH were the main factors correlated with population density of gastropod communities. T. granifera often reached densities well over 1000 ind. m?2, displacing indigenous gastropods and becoming a dominant component of the benthic community. T. granifera successfully invaded estuaries despite frequent exposure to high salinity and desiccation, which could together eliminate >97% of the population. The persistence of T. granifera was ensured due to its high fecundity and the environmental tolerance of large adults (20–30 mm SH) which carried an average of 158±12.8 SD brooded juveniles. Repeat introductions were not essential for the success of this parthenogenetic NIS. Conclusion/Significance There is a need for a broader study on the reproductive biology of T. granifera (including the previously overlooked “brood pouch ecology”), which affects population dynamics and may be relevant to other parthenogenetic NIS, such as Melanoides tuberculata and Potamopyrgus antipodarum.

Miranda, Nelson A. F.; Perissinotto, Renzo; Appleton, Christopher C.

2011-01-01

164

Correlation between snails and fish in fish ponds of World Fish Center (ICLARM) with special reference to snail vectors of schistosomiasis and fascioliasis.  

PubMed

The abundance of snail species in earthen fish ponds, irrigation and drainage canals at World Fish Center (ICLARM) in descending order was Bellamya unicolor (50.89%) > Physa acuta (18.94%) > Cleopatra bulimoides (7.6%) > Lanistes carinatus (6.73%) > Bulinus truncatus (5.19%) > Melanoides tuberculata (4.83%) > Lymnaea natalensis (3.14%) > Gabbiella senaariensis (0.9%) > Biomphalaria alexandrina (0.55%) > Lym naea truncatula (0.4%) > Planorbis planorbis and Succinea cleopatra (0.33%) > Ferrissia isseli (0.18%). Dead snails constituted about 5.19% of all the collected specimens. There were dramatic decrease in the total number of pulmonates in fish ponds which contained only Tilapia sp., and a very small number of cat fish, whereas the numbers of prosobranchia snails were much higher in these ponds. In fish ponds which accommodated a variety of fish species, the most dominant snail was B. unicolor followed by L. carinatus. However, pulmonate snails were absent in these ponds. B. truncatus was the only snail species found in concrete tank which contained only young tilapias with a very small size (5-8 cm in standard length). In irrigation canals, the number of snails and diversity was much higher than those in fish ponds. Out of 191 snails collected from inlet irrigation canal, 71 were dead, but in the outside irrigation canals, seven out of 564 snails were dead. P. acuta was absent in all examined fish ponds, but it was alive and in a high number (497 snails) in the outside irrigation canals. The number of snails collected from Bahnasawy drain was remarkably low (128 snails), however the diversity of snails was much higher compared to those in fish ponds and irrigation canals. Snail populations were stable with constant recruitment of young to adult snails for all the studied species. PMID:14964656

Ismail, Nahed M M; El Gamal, Abd El Rahman A

2003-08-01

165

Trematode metacercariae of fishes as sentinels for a changing limnological environment.  

PubMed

Trematode metacercaria populations infecting cichlids in Lake Kinneret (Sea of Galilee) were used as sentinels for the changing limnological environment. Parasitological data from 0+ cichlid fingerlings (Tilapia zillii, Oreochromis aureus, Sarotherodon galilaeus) were collected from the northwest shore of the lake during 1999 to 2001 and compared with data obtained from 1982 to 1984. The results show that the composition of the metacercarial populations changed significantly between the 2 samplings periods. The total number of metacercarial species found in the Kinneret cichlids was lower in 1999 to 2001 than in 1982 to 1984. Metacercariae transmitted by the snail Bulinus truncatus (Clinostomum tilapiae, Euclinostomum heterostomum, Bolbophorus levantinus and Neascus-type metacercariae--black spot and others) that were commonly found in 1982 to 1984 were absent from the fishes sampled during 1999 to 2001. The other trematode metacercariae (Centrocestus sp. and Haplorchis sp. transmitted by Melanoides tuberculata, Pygidiopsis genata transmitted by Melanopsis costata, as well as Phagicola longa, Strigeidae sp.1, an unidentified metacercaria typically found in the liver, and glochidia) increased in abundance in fishes sampled during 1999 to 2001. The calculated 'true' species richness of the habitat, extrapolated as a function of sampling effort, was significantly lower in the 1999 to 2001 versus 1982 to 1984 samples, while significantly fewer fishes needed to be sampled ('sampling effort') during 1999 to 2001 in order to reach the 'true' species richness. The higher calculated values of species richness and diversity for the 1999 to 2001 samples despite the overall decline in species number is explained by the overall increase in metacercariae prevalence. PMID:12911062

Dzikowski, R; Diamant, A; Paperna, I

2003-07-01

166

Impact of certain plants and synthetic molluscicides on some fresh water snails and fish.  

PubMed

The LC50 (78, 85 ppm) and LC90 (88, 135 ppm) of Anagalis arvensis and Calendula micrantha respectively against Biomphalaria alexandrina were higher than those of the non-target snails, Physa acuta, Planorbis planorbis, Helisoma duryi and Melanoides tuberculata. In contrast, the LC50 of Niclosamide (0.11 ppm) and Copper sulphate (CuSO4) (0.42 ppm) against B. alexandrina were lower than those of the non-target snails. The mortalities percentage among non-target snails ranged between 0.0 & 20% when sublethal concentrations of CuSO4 against B. alexandrina mixed with those of C. micrantha and between 0.0 & 40% when mixed with A. arvensis. Mortalities ranged between 0.0 & 50% when Niclosamide was mixed with each of A. arvensis and C. micrantha. A. arvensis induced 100% mortality on Oreochromis niloticus after 48 hrs exposure and after 24 hrs for Gambusia affinis. C. micrantha was non-toxic to the fish. The survival rate of O. niloticus and G. affinis after 48 hrs exposure to 0.11 ppm of Niclosamide were 83.3% & 100% respectively. These rates were 91.7% & 93.3% respectively when each of the two fish species was exposed to 0.42 ppm of CuSO4. Mixture of sub-lethal concentrations of A. arvensis against B. alexandrina and those of Niclosamide or CuSO4 at ratios 10:40 & 25:25 induced 66.6% mortalities on O. niloticus and 83.3% at 40:10. These mixtures caused 100% mortalities on G. affinis at all ratios. A. arvensis CuSO4 mixtures at 10:40 induced 83.3% & 40% mortalities on O. niloticus and G. affinis respectively and 100% mortalities on both fish species at ratios 25:25 & 40:10. A mixture of sub-lethal concentrations of C. micrantha against B. alexandrina and of Niclosamide or CuSO4 caused mortalities of O. niloticus between 0.0 & 33.3% and between 5% & 35% of G. affinis. The residue of Cu in O. niloticus were 4.69, 19.06 & 25.37 mg/1kgm fish after 24, 48 & 72 hrs exposure to LC0 of CuSO4 against B. alexandrina respectively. PMID:16333905

Mosta-Fa, B B; el-Deeb, Fatma A; Ismail, Nahid M; el-Said, K M

2005-12-01

167

Seedling growth of the invader Calotropis procera in ironstone rupestrian fi eld and seasonally dry forest soils Crescimento de plântulas da espécie invasora Calotropis procera em solos de campos rupestres ferruginosos e fl oresta seca sazonal  

Microsoft Academic Search

The present study evaluated the growth, biomass allocation and nutrient content in seedlings of the invasive and exotic especies Calotropis procera (Aiton) W.T. Aiton (Apocynaceae), cultured in greenhouse, in soils from two different ecosystems: ironstone rupestrian fi elds (Canga) of Brumadinho, Minas Gerais; and seasonally dry forest (Caatinga), of Serra Talhada, Pernambuco. Seedlings from the Canga treatment were signifi cantly

Silvia H. F. de Oliveira; Daniel Negreiros; G. Wilson Fernandes; Newton P. U. Barbosa

168

The integrated culture of seaweed, abalone, fish and clams in modular intensive land-based systems: II. Performance and nitrogen partitioning within an abalone ( Haliotis tuberculata) and macroalgae culture system  

Microsoft Academic Search

A pilot-scale system for the intensive land-based culture of abalone was established using an integrated design aimed at eliminating the dependence on external food sources, whilst reducing water requirements and nutrient discharge levels. The system was the first and simplest trial in a series of progressive complexity of the concept of integrated culture of seaweed, abalone, fish and clams in

Amir Neori; Norman L. C. Ragg; Muki Shpigel

1998-01-01

169

Structural distortion of biogenic aragonite in strongly textured mollusc shell layers  

Microsoft Academic Search

The stabilisation of strong textures in mollusc shells has for long been a strong drawback towards precise structural determinations of these natural biocomposites. We demonstrate here on several crossed lamellar and nacre layers from two gastropods (Charonia lampas lampas and Haliotis tuberculata tuberculata) and one bivalve (Pinctada maxima), that on real specimens (without grinding or specific preparation), the textural information

D. Chateigner; S. Ouhenia; C. Krauss; M. Belkhir; M. Morales

2010-01-01

170

Bats that walk: a new evolutionary hypothesis for the terrestrial behaviour of New Zealand's endemic mystacinids  

Microsoft Academic Search

BACKGROUND: New Zealand's lesser short-tailed bat Mystacina tuberculata is one of only two of c.1100 extant bat species to use a true walking gait when manoeuvring on the ground (the other being the American common vampire bat Desmodus rotundus). Mystacina tuberculata is also the last surviving member of Mystacinidae, the only mammalian family endemic to New Zealand (NZ) and a

Suzanne J Hand; Vera Weisbecker; Michael Archer; Henk Godthelp; Alan JD Tennyson; Trevor H Worthy

2009-01-01

171

Effect of three dormant oils on schistosomiasis and fascioliasis vector snails and its relation with some non-target snails.  

PubMed

Three oils were tested for their molluscicidal activity, Caple-2, Kemasol and Super-max. Super-max had the strongest toxic effect on B. alexandrina and other snail species. Its LC50 was 0.53 ppm, meanwhile LC50 of Kemasol 3.2 ppm and 4.21 ppm for Caple 2. The LC50 & LC90 of the oils were lower in Lymneae natalensis as compared to B. alexandrina. The LC50 & LC90 of the oils against non-target snails (Physa acuta, Helisoma duryi, Planorbis planorbis and Melanoides tuberculata) were higher as compared to B. alexandrina. Hatchability of snails' eggs exposed to Super-max (3.0 & 5.0 ppm) was stopped completely and l.0 ppm showed the lower percent of egg hatchability 22.7 %. Caple 2 and Kemasol did not affect eggs hatchability. Supermax had the strongest harmful effect on both miracidia and cercariae of S. mansoni. 100% mortality values were obtained for both larval stages after 8 & 9 minutes respectively when maintained at LC50. 100% mortality of miracidia occurred after 35 & 155 minutes when maintained at LC50 of Kemasol & Caple 2 respectively. The infection rate of B. alexandrina with S. mansoni miracidia was greatly reduced by the sublethal concentrations of the oils. The reduction of infection rate was higher in snails treated with Supermax (42.9%). A highly significant reduction of total cercarial production per snail was in the experimental groups as compared with controls. The prepatent period of treated snails was prolonged compared to control. Moreover, Total protein content and enzyme activities of snails treated with LC10 of oils showed a significant reduction as compared with control in haemolymyph. There was an increase of protein contents in the tissue. AlkP enzyme activity was slightly increased in haemolymph of experimental groups than controls and was significantly higher in the tissues as compared to control. ALT enzyme activity in haemolymph of experimental groups was higher than control, but lower in tissue. AST enzyme activity was higher in haemolymph and tissue of experimental groups than controls. The SDS-PAGE pattern of tissue soluble proteins extracted from treated B. alexandrina and controls showed different oils effects on the synthesis of protein within snails yielded a complex pattern of polypeptides ranging in molecular weight between 13.775 to 156.7 kDa. Many bands were present in treated snails. At least, one band was detected for snails treated with each of the oils and not in controls. The difference in the similarity indices between treatment and control; for Kemasol was 0.86 & 0.64, for Caple 2 was 0.61 & 0.55 and for Supermax was 0.64 & 0.86. LC25 of Supermax did not cause any mortality to Daphnia after 6 hr. But, LC50 & LC90 caused lower mortality after 6 hr. Kemasol caused 100% mortality after 4 hr at LC50 and 2 hr in LC90. Caple 2 caused 50% mortality of Daphnia after 5 hr at LC25 &100% mortality after 30 minutes in LC50 & LC90. PMID:17153697

Mostafa, Bayaumy B

2006-12-01

172

Relative abundance and distribution of fishes and crayfish at Ash Meadows National Wildlife Refuge, Nye County, Nevada, 2010-11  

USGS Publications Warehouse

Ash Meadows National Wildlife Refuge (AMNWR) was established by the U.S. Fish and Wildlife Service (with the assistance of The Nature Conservancy) in 1984 to protect one of the highest concentrations of endemic flora and fauna in North America (Pister, 1985; Sada, 1990). Prior to federal acquisition, Ash Meadows had been anthropogenically altered, and non-native species had been introduced to the detriment of native species; reports and published literature document the negative effects to the Ash Meadows flora and fauna (Deacon and others, 1964; U.S. Department of the Interior, 1971; Landye, 1973; Pister, 1974; Soltz and Naiman, 1978; Taylor, 1980; Williams and others, 1985; Williams and Sada, 1985; Baugh and others, 1986; Hershler and Sada, 1987; Knight and Clemmer, 1987; Sada, 1990; Deacon and Williams, 1991; Scoppettone and others, 2005; Kennedy and others, 2006). Such activities led to the extinction of the endemic Ash Meadows poolfish (Empetrichthyes merriami) (Miller, 1961; Soltz and Naiman, 1978), and subsequently the federal government listed three local endemic fish as endangered pursuant to the Endangered Species Act (U.S. Fish and Wildlife Service, 1989)—Warm springs pupfish (Cyprinodon nevadensis pectoralis), Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes), and Ash Meadows speckled dace (Rhinichthys osculus nevadensis). Public ownership of a large portion of Ash Meadows provided the opportunity to restore the landscape to some semblance of its historical condition. Elimination of invasive aquatic species may be more difficult than landscape restoration, and their persistence can cause additional native fish decline or extirpation (Taylor and others, 1984; Moyle and others, 1986; Miller and others, 1989; Minckley and Deacon, 1991; Olden and Poff, 2005). Chemical treatment to remove invasive fishes is often unsuccessful (Meffe, 1983; Rinne and Turner, 1991; Meronek and others, 1996). In Ash Meadows, there has been some success in chemical eradication of localized populations of largemouth bass (Micropterus salmoides) and black bullhead (Ameiurus melas) (St. George, 1998, 1999; Weissenfluh, 2008b), as well as convict cichlid (Archocentrus nigrofasciatus) and sailfin molly (Poecilia latipinna) (Weissenfluh,2008a). However, there has been less success in removing western mosquitofish (Gambusia affinis) from Ash Meadows's larger spring systems, and sailfin molly maintains strongholds in several spring systems (Scoppettone and others, 2011b). Perhaps the more destructive invasive species are two invertebrates: red swamp crayfish (Procambarus clarkii) and red-rim melania (Melanoides tuberculata). Following the appearance of red swamp crayfish within the Warm Springs Complex, Warm Springs pupfish was believed to be extirpated from one spring system (St. George, 2000) and near extirpation in two others (Darrick Weissenfluh, Ash Meadows National Wildlife Refuge, oral commun., 2008, 2011). Crayfish also were demonstrated to greatly suppress the Bradford Springs population of Ash Meadows speckled dace population (McShane and others, 2004). Red-rim melania is known to displace native snail populations (Mitchell and others, 2007), and has been implicated as an agent of extinction of native Ash Meadows spring-snails (Donald Sada, Desert Research Institute, oral commun., 2011). Both invasive invertebrates are difficult to control or eradicate (Mitchell and others, 2007; Freeman and others, 2010). Habitat restoration that favors native species can help control non-native species (McShane and others, 2004; Scoppettone and others, 2005; Kennedy and others, 2006). Restoration of Carson Slough and its tributaries present an opportunity to promote habitat types that favor native species over non-natives. Historically, the majority of Ash Meadows spring systems were tributaries to Carson Slough. In 2007 and 2008, a survey of Ash Meadows spring systems was conducted to generate baseline information on the distribution of fishes throughout AMNWR (Scoppettone and others, 2011b). In this study, we conducted a follo

Scoppettone, G. G.; Johnson, D. M.; Hereford, M. E.; Rissler, Peter; Fabes, Mark; Salgado, Antonio; Shea, Sean

2012-01-01

173

COMPARATIVE TOXICITY OF CHEMICALS TO EARTHWORMS  

EPA Science Inventory

The concentration-response (mortality) relationships of four species of earthworms, Eisentia fetida, Allolobophora tuberculata, Eudrilus eugeniae, and Perionyx excavatus are summarized for 62 chemicals and two test protocols. eibull function is used to summarize these data for ea...

174

Comparative Toxicity of Chemicals to Earthworms.  

National Technical Information Service (NTIS)

The concentration-response (mortality) relationships of four species of earthworms, Eisentia fetida, Allolobophora tuberculata, Eudrilus eugeniae, and Perionyx excavatus are summarized for 62 chemicals and two test protocols. A Weibull function is used to...

C. A. Callahan M. A. Shirazi E. F. Neuhauser

1994-01-01

175

COMPARATIVE TOXICITY OF TEN ORGANIC CHEMICALS TO FOUR EARTHWORM SPECIES  

EPA Science Inventory

Ten organic chemicals were tested for toxicity to four earthworm species: Allolobophora tuberculata, Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus, using the European Economic Community's (EEC) earthworm artificial soil and contact testing procedure. The phenols were t...

176

Comparative Toxicity of Ten Organic Chemicals to Four Earthworm Species.  

National Technical Information Service (NTIS)

Ten organic chemicals were tested for toxicity to four earthworm species: Allolobophora tuberculata, Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus, using the European Economic Community's (EEC) earthworm artificial soil and contact testing proc...

E. F. Neuhauser P. R. Durkin M. R. Malecki M. Anatra

1986-01-01

177

Helobdella nilae and Alboglossiphonia conjugata leeches as biological agents for snails control.  

PubMed

The efficacy of leeches, as biological agents, in control of snail intermediate hosts of schistosomiasis (Bulinus truncatus, Biomphalaria alexandrina) and fascioliasis (Lymnaea natalensis) as well as their effect on the non-target snails Physa acuta, Melanioides tuberculata and Cleopatra bulimoides was evaluated. Two glossiphoniid snail leeches, Helobdella nilae and Alboglossiphonia conjugata were used. They destroyed egg masses and young snails more rapidly than adult ones. H. nilae showed a stronger destructive effect than A. conjugata. In a descending order, it preferred L. natalensis followed by B. truncatus, B. alexandrina, Ph. acuta, M. tuberculata and lastly C. bulimoides. But, A. conjugata preferred L. natalensis followed by B. truncatus, Ph. acuta, M. tuberculata, B. alexandrina and lastly C. bulimoides. The detailed diagnostic morphology and biology of the two leeches were given. PMID:19530628

Abd-Allah, Karim F; Saleh, Mohamed H; El-Hamshary, Azza M S; Negm-Eldin, Mohsen M; El-Fakahany, Amany F; Abdel-Tawab, Ahmed H; Abdel-Maboud, Amina I; Aly, Nagwa S M

2009-04-01

178

Freshwater snails of Oman, South Eastern Arabia  

Microsoft Academic Search

A systematic account is given of the extant freshwater snail fauna of Oman, based on recent collections made in Dhofar and in the northern mountainous areas. Also included are certain species found in brackish coastal localities. A total of 8 freshwater species is regarded as belonging to the fauna of normal freshwater; 7 have been found alive (Thiara scabra, Melanoides

D. S. Brown; M. D. Gallagher

1985-01-01

179

Crush-resistance of soft-sediment gastropods of Lake Mala?i: implications for prey selection by Molluscivorous fishes  

Microsoft Academic Search

An increase in human urinary schistosome transmission in southern Lake Mala?i has been suggested to be associated with decreased density of molluscivorous fishes due to illegal seine-net fishing from the shore. In addition, the increased density of snails (Melanoides spp.) through the invasion of an Asian morph could have changed the predators’ prey choice. At Chembe village, the intermediate host

B. N. Evers; H. Madsen; J. R. Stauffer Jr

2011-01-01

180

The integrated culture of seaweed, abalone, fish and clams in modular intensive land-based systems: I. Proportions of size and projected revenues  

Microsoft Academic Search

Three environmentally friendly modular designs for integrated mariculture are described. The basic design consists of modules for the culture of seaweed (Ulva lactuca or Gracilaria spp.) and abalone (Haliotis tuberculata). Modules for the culture of fish (Sparus aurata) and then clams (Tapes philippinarum) are subsequently connected in two progressively complex systems. The modular design allows flexibility in the allocation of

Muki Shpigel; Amir Neori

1996-01-01

181

Mixotrophic versus photoautotrophic specialist algae as food for zooplankton: The light : nutrient hypothesis might not hold for mixotrophs  

Microsoft Academic Search

We reared mixotrophic (Ochromonas tuberculata and Cryptomonas sp.) and photoautotrophic specialist algae (Scenedesmus obliquus) at different light : phosphorus supplies and compared their effects as food for zooplankton (Daphnia magna). According to the light : nutrient hypothesis (LNH), biomass and nutrient stoichiometry of pho- totrophic specialists depend strongly on light : phosphorus supplies. If this is true, herbivore growth and

Alexis Katechakis; Tanja Haseneder; Robert Kling; Herwig Stibor

2005-01-01

182

Gelidium robustum agar: quality characteristics from exploited beds and seasonality from an unexploited bed at Southern Baja California, México  

Microsoft Academic Search

The yield and gel properties of agar from Gelidium robustum, harvested in Baja California for industrial production is affected by season of collection and epiphyte loading. The alga is epiphytized to various extents by the bryozoan Membraniphora tuberculata ('conchilla') and the resulting calcareous crust on the alga diminishes the price of the seaweed biomass. Classification of the algal biomass quality

Y. Freile-Pelegrín; D. Robledo; E. Serviere-Zaragoza

1999-01-01

183

Evolutionary History and Taxonomy of the Cuscuta umbellata complex (Convolvulaceae): Evidence of Extensive Hybridization from Discordant Nuclear and Plastid Phylogenies  

Microsoft Academic Search

The Cuscuta umbellata complex is one of the 15 major clades recently circumscribed in C. subg. Grammica. Most of its members occur in North AMerican and the Caribbean (C. desmouliniana, C. lacerata, C. lacerata, C. leptantha, C. liliputana, C. odontolepsis, C. polyanthemos, C. tuberculata, C. umbellata), but three species (C. acuta, C. membranacea, C. umbellata) grow in South America, and

Mihai Costea; Saša Stefanovi?

2010-01-01

184

A SURVEY OF THE DISTRIBUTION, SEASONAL ACTIVITY AND ROOST SITES OF NEW ZEALAND BATS  

Microsoft Academic Search

Summary: The lesser short-tailed bat (Mystacina t. tuberculata) has been found in 18 locations in indigenous forest in North Island since 1961, mainly in Northland kauri forest (including Little Barrier Island), on the volcanic plateau (including Tongariro National Park), Urewera National Park and in Tararua Range. In South Island this bat has only been reported once since 1961, in North

M. J. DANIEL; G. R. WILLIAMS

185

Two new species of Ophidiasterid sea-stars from the vicinity of Diaoyudao, East China Sea  

NASA Astrophysics Data System (ADS)

Two new species of the asteroid family Ophidiasteridae are described from two specimens collected by commercial fishery vessels of Qingdao from the vicinity of Diaoyudao (25°45'N, 123°15'E), East China Sea. Hacelia tuberculata sp. nov. shows affinities with H. tyloplax (H. L. Clark, 1914) and Linckia gracilis sp. nov. is related to L. laevigata (Linnaeus).

Liao, Yulin

1985-06-01

186

Gene expression patterns in a novel animal appendage: the sea urchin pluteus arm.  

PubMed

The larval arms of echinoid plutei are used for locomotion and feeding. They are composed of internal calcite skeletal rods covered by an ectoderm layer bearing a ciliary band. Skeletogenesis includes an autonomous molecular differentiation program in primary mesenchyme cells (PMCs), initiated when PMCs leave the vegetal plate for the blastocoel, and a patterning of the differentiated skeletal units that requires molecular cues from the overlaying ectoderm. The arms represent a larval feature that arose in the echinoid lineage during the Paleozoic and offers a subject for the study of gene co-option in the evolution of novel larval features. We isolated new molecular markers in two closely related but differently developing species, Heliocidaris tuberculata and Heliocidaris erythrogramma. We report the expression of a larval arm-associated ectoderm gene tetraspanin, as well as two new PMC markers, advillin and carbonic anhydrase. Tetraspanin localizes to the animal half of blastula stage H. tuberculata and then undergoes a restriction into the putative oral ectoderm and future location of the postoral arms, where it continues to be expressed at the leading edge of both the postoral and anterolateral arms. In H. erythrogramma, its expression initiates in the animal half of blastulae and expands over the entire ectoderm from gastrulation onward. Advillin and carbonic anhydrase are upregulated in the PMCs postgastrulation and localized to the leading edge of the growing larval arms of H. tuberculata but do not exhibit coordinated expression in H. erythrogramma larvae. The tight spatiotemporal regulation of these genes in H. tuberculata along with other ontogenetic and phylogenetic evidence suggest that pluteus arms are novel larval organs, distinguishable from the processes of skeletogenesis per se. The dissociation of expression control in H. erythrogramma suggest that coordinate gene expression in H. tuberculata evolved as part of the evolution of pluteus arms, and is not required for larval or adult development. PMID:17227366

Love, Alan C; Andrews, Mary E; Raff, Rudolf A

187

Introduction, distribution, spread, and impacts of exotic freshwater gastropods in Texas  

Microsoft Academic Search

We examined the patterns of distribution, vectors of introduction, and potential ecological impacts of freshwater exotic species\\u000a in Texas over the last 45 years. Currently, five species of exotic gastropods are established: channeled-type applesnail (Pomacea insularum), red-rim melania (Melanoides tuberculatus), quilted melania (Tarebia granifera), giant rams-horn snail (Marisa cornuarietis), and Chinese mysterysnail (Cipangopaludina\\u000a chinensis). In contrast to the northern part of

Alexander Y. Karatayev; Lyubov E. Burlakova; Vadim A. Karatayev; Dianna K. Padilla

2009-01-01

188

Use of Bayluscide (Bayer 73) for Snail Control in Fish Ponds  

Microsoft Academic Search

Bayluscide applied to ponds on two commercial fish farms at five rates (from L1 to 13.5 kilogram per surface hectare) effectively controlled aquatic snails. Laboratory toxicity tests confirmed susceptibility of three endemic species of aquatic snail—Melanoides tuberculatus, Physella hendersoni, and Planorbella duryi—to Bayluscide. Observed 24-h concentrations lethal to 50% of snails (LC50) ranged from 0.062 to 0.085 mg\\/L, and 24-h

Ruth Francis-Floyd; James Gildea; Peggy Reed; Ruthellen Klinger

1997-01-01

189

Use of Ice-Water and Salt Treatments to Eliminate an Exotic Snail, the Red-Rim Melania, from Small Immersible Fisheries Equipment  

Microsoft Academic Search

Ice-water and salt treatments were evaluated for disinfection of small immersible fisheries equipment contaminated with a nonindigenous tropical snail, the red-rim melania Melanoides tuberculatus. This introduced species can displace native snails and transmit trematodes directly to fish and indirectly to other animals, including humans. The red-rim melania has a well-developed operculum that protects it from desiccation and allows it to

Andrew J. Mitchell; Thomas M. Brandt

2009-01-01

190

Streptomyces bungoensis sp. nov  

Microsoft Academic Search

Two actinomycete strains, MS16-1OG and MS16-1OW, isolated from soil and producing an antibiotic, were examined and assigned to the genus Streptomyces, because they have a gray aerial mass, spiral spore chains, and a spiny spore surface; form a melanoid pigment on tyrosine agar, on peptone-yeast extract-iron agar, and in tryptone-yeast extract broth; and have cell wall chemotype I. The DNA

TORU EGUCHI; NOBUO TAKADA; SHOJI NAKAMURA; TOSHIYUKI TANAKA; TAKETOSHI MAKIN; YASUJI OSHIMA

191

Maternal factors and the evolution of developmental mode: Evolution of oogenesis in Heliocidaris erythrogramma  

Microsoft Academic Search

Evolutionary change in developmental mode in sea urchins is closely tied to an increase in maternal provisioning. We examined\\u000a the oogenic modifications involved in production of a large egg by comparison of oogenesis in congeneric sea urchins with\\u000a markedly different sized oocytes and divergent modes of development. Heliocidaris tuberculata has small eggs (95 µm diameter) and the ancestral mode of development

M. Byrne; Jeffrey T. Villinski; Paula Cisternas; Rebecca K. Siegel; Ellen Popodi; Rudolf A. Raff

1999-01-01

192

Growth dynamics of root and shoot hydraulic conductance in seedlings of five neotropical tree species: scaling to show possible adaptation to differing light regimes  

Microsoft Academic Search

The dynamics of growth (shoot and root dry weights, surface areas, hydraulic conductances, and root length) were measured\\u000a in seedlings of five neotropical tree species aged 4–16 months. The species studied included two light-demanding pioneers\\u000a (Miconia argentea and Apeiba membranacea) and three shade-tolerant young- or old-forest species (Pouteria reticulata, Gustavia superba, and Trichilia tuberculata). Growth analysis revealed that shoot and

Melvin T. Tyree; Virginia Velez; J. W. Dalling

1998-01-01

193

Tanaidaceans (Crustacea) from the Central Pacific Manganese Nodule Province. I. The genera Collettea, Robustochelia and Tumidochelia  

PubMed Central

Abstract Three new species of are described from the manganese nodule province between the Clarion and the Clipperton Fracture Zone of the equatorial North Pacific Ocean, and collected during the Nodinaut expedition on board the r/v l´Atalante in the summer of 2004. The new species belongs to three genera as: Collettea (Collettea longisetosa), Robustochelia (Robustochelia pacifica), and Tumidochelia (Tumidochelia tuberculata). A key to the genus Tumidochelia is presented and the validity of the genera Robustochelia and Collettea is discussed.

Larsen, Kim

2011-01-01

194

3D reconstruction of the hemocyanin subunit dimer from the chiton Acanthochiton fascicularis.  

PubMed

Procedures are presented for the purification of the subunit dimer from Acanthochiton fasicularis hemocyanin. Electron microscopy of negatively stained specimens revealed a uniform population of macromolecules possessing the characteristic "boat shape". A 3D reconstruction from this EM data generated a approximately 3 nm resolution model that correlates well with earlier data of the purported subunit dimer, extracted from the 3D reconstruction of the didecamer of Haliotis tuberculata hemocyanin type 1. PMID:15036283

Harris, J Robin; Meissner, Ulrich; Gebauer, Wolfgang; Markl, Jürgen

2004-01-01

195

Effects of earthworms on decomposition and metal availability in contaminated soil: Microcosm studies of populations with different exposure histories  

Microsoft Academic Search

Population-specific differences in the responses of earthworms to simultaneous exposure to Cu and Zn were studied in microcosm experiments. Two populations of Aporrectodea caliginosa tuberculata (Eisen) with different metal exposure histories were chosen for the studies. Microcosms were prepared containing either uncontaminated soil or soils with low or high combined Cu\\/Zn -concentrations (79\\/139 or 178\\/311mgkg?1 dry mass of soil, respectively).

Tuomas Lukkari; Sanra Teno; Ari Väisänen; Jari Haimi

2006-01-01

196

Energy Use During the Development of a Lecithotrophic and a Planktotrophic Echinoid  

Microsoft Academic Search

The energy required for development was measured in two closely related echinoids with differing modes of development. Heliocidaris tuberculata hatches from a 95-pm egg (-0.1 pg dry organic mass) and devel- ops via a planktotrophic larva over 2 l-30 days into a ju- venile (5.3-7.5 pg). H. erythrogramma hatches from a -400 pm egg (11.6-19.0 pg) and develops over 3.5-

R. B. EMLET

197

A study on biological control of six fresh water snails of medical and veterinary importance.  

PubMed

This study evaluated the molluscicidal effect of Commiphora mnolmol oil extract (Myrrh), on control of six fresh water snails (Lymnaea natalensis, Bulinus truncatus, Biomphalaria alexandrina, Physa acuta, Melania tuberculata and Cleopatra bulimoides). Also, the extract effect on the egg masses of L. natalensis, B. truncatus, B. alexandrina and Ph. acuta was evaluated. Snails and egg masses were exposed at 16-20 degrees C to various concentrations (conc.). LD50 after 24 hours expo-sure were 264/132, 283/195, 230/252, 200/224, 241/246 & 241/246 ppm for young/adult of L. natalensis, B. truncatus, B. alexandrina, Ph. acuta, M. tuberculata and C. bulimnoides respectively. LDtoo after 24 hours exposure were 400/400 for L. natalensis, B. truncatus, B. alexandrina, M. tuberculata and C. bulimoides, and 300/300 for Ph. acuta. Also, complete mortality (100%) was achieved for the egg masses of L. natalensis, B. truncatus, B. alexandrina and Ph. acuta at concentrations of 300, 200, 300 & 400 ppm respectively. Lower concentrations gave the same results after longer exposure. LD100 of C. molmol oil extract (Myrrh) had a rapid lethal effect on the six snail species and their egg masses in high conc. of 300 & 400 ppm. Commiphora molmol is a promising plant to be included with the candidate plant molluscicides. The oil extract of this plant showed a remarkable molluscicidal activity against used snail species. PMID:19530615

Abd-Allah, Karim F; Negm-Eldin, Mohsen M; Saleh, Mohamed H; El-Hamshary, Azza M S; El-Gozamy, Bothina M R; Aly, Nagwa S M

2009-04-01

198

Life-history strategies affect aphid preference for yellowing leaves  

PubMed Central

According to the nutrient-translocation hypothesis, yellowing tree leaves are colonized by aphids at the end of the growing season owing to improved availability of nutrients in the phloem sap after chlorophyll degradation. We measured aphid densities on potted Betula pendula seedlings in a field site where a small proportion of foliage rapidly turned yellow before normal autumn coloration as a consequence of root anoxia. The number of adults and nymphs of the birch-feeding specialist aphids Euceraphis betulae, Betulaphis brevipilosa and Callipterinella tuberculata were counted from leaves on each of the 222 plants. Aphids were detected on 19 per cent of green leaves and on 41 per cent of yellow leaves. There was no indication of aphid avoidance of yellow leaves, and the number of winged (alate) viviparous E. betulae adults and their nymphs were significantly higher on yellow leaves than on green leaves, while the numbers of apterous B. brevipilosa and C. tuberculata did not differ between the leaf colour types. Our result suggests that only aphid species with alate generation during colour change can take advantage of yellowing leaves. This may explain the exceptional abundance of E. betulae compared with other aphid species on birches.

Holopainen, Jarmo K.; Semiz, Gurkan; Blande, James D.

2009-01-01

199

Life history and identification of Philophthalmus lucipetus from Israel.  

PubMed

A Philophthalmus species whose larval stages have been isolated from Melanopsis praemorsa snails collected in Israel and formerly identified as probably belonging to Philophthalmus palpebrarum has now been reevaluated as belonging to Philophthalmus lucipetus. The present determination is based on a detailed study of all the stages of the parasite's life cycle--eggs, intramolluscan stages, cercariae, and adults. They were compared to the original species P. lucipetus, recently reexamined and redescribed from source material in Vienna, Austria. The identity of the eyefluke from Israel and P. lucipetus was further confirmed by successful cross-infections employing miracidia of the Israeli isolate in European (Bulgarian) Fagotia acicularis acicularis snails on the one hand and miracidia of P. lucipetus from Bulgaria in Israeli Melanopsis praemorsa on the other hand, but none infected Melanoïdes tuberculata snails from Israel. PMID:10219311

Radev, V; Kanev, I; Nollen, P M; Gold, D

1999-04-01

200

Bdelloid Rotifers from Lakes above 1700 m in Western Italian Alps, with Taxonomic Notes on Dissotrocha macrostyla  

NASA Astrophysics Data System (ADS)

Benthic and periphytic bdelloid communities from 16 alpine lakes from 1700 to 2850 m above sea level in Sesia Valley (Piedmont region, North-western Italy), sampled during summer 2001 and 2002, were analyzed. Seventeen species were identified from these species-poor communities, with 1 to 6 species each. Dissotrocha macrostyla and Philodina citrina were the most common species, present in 10 lakes while 9 species were collected from one lake only. New morphological details from S.E.M. pictures of Dissotrocha macrostyla revealed that Dissotrocha macrostyla tuberculata (Gosse, 1886) is only a seasonal morphotype. Its different appearance is due to the presence of locally distributed microscopic mucous bubbles (diameter 1.41 +/- 0.18 m) on the trunk surface, produced by the rotifer itself under stressful conditions.

Fontaneto, Diego; Melone, Giulio

2003-11-01

201

A Partial Revision of the Marine Nematode Genus Elzalia (Monhysterida: Xyalidae) with New Characters and Descriptions of Two New Species from Khung Kraben Bay, East Thailand  

PubMed Central

Elzalia bipectinella1 n. sp. and E. tuberculata2 n. sp. from Thailand are described and the males of three species from the Gulf of Mexico, E. federici Castillo-Fernandez and Lambshead (1990), E. kimae Castillo-Fernandez and Lambshead (1990), and E. poli Castillo-Fernandez and Lambshead (1990) are re-described from type and topotype specimens using light and scanning electron microscopy. New morphological characters are described that include ornamentations at the distal end of the spicula and features of the gubernaculum including the manus with digits, pontis with sensory receptor and accessory process, and the condylus with either conical or foliate projections. Also, ejaculatory and rectal glands are described for the first time for Elzalia. The relevance of the new characters to the taxonomy of Elzalia is discussed. A key to identification of males is provided. A generalized description of females is given, although characters are lacking by which females of each species may be identified.

Hope, W. Duane; Aryuthaka, Chittima

2009-01-01

202

Construction of a stable GFP-tagged Vibrio harveyi strain for bacterial dynamics analysis of abalone infection.  

PubMed

Vibrio harveyi is a bacterial marine pathogen that can cause fatal disease in a large range of vertebrates and invertebrates, including the commercially important marine gastropod, Haliotis tuberculata. Since 1997, strains of this bacterium have regularly been causing high mortalities in farmed and wild abalone populations. The way in which the pathogen enters into abalone and the disease transmission mechanisms are thus far unknown. Therefore, a pathogenic strain, ORM4, was green fluorescent protein-tagged and validated both for its growth characteristics and for its virulence as a genuine model for abalone disease. The strain allows V. harveyi quantification by flow cytometry in seawater and in abalone haemolymph as well as the in situ detection of the parasite inside abalone tissues. PMID:19054091

Travers, Marie-Agnès; Barbou, Annaïck; Le Goïc, Nelly; Huchette, Sylvain; Paillard, Christine; Koken, Marcel

2008-12-01

203

Molluscan mega-hemocyanin: an ancient oxygen carrier tuned by a ~550 kDa polypeptide  

PubMed Central

Background The allosteric respiratory protein hemocyanin occurs in gastropods as tubular di-, tri- and multimers of a 35 × 18 nm, ring-like decamer with a collar complex at one opening. The decamer comprises five subunit dimers. The subunit, a 400 kDa polypeptide, is a concatenation of eight paralogous functional units. Their exact topology within the quaternary structure has recently been solved by 3D electron microscopy, providing a molecular model of an entire didecamer (two conjoined decamers). Here we study keyhole limpet hemocyanin (KLH2) tridecamers to unravel the exact association mode of the third decamer. Moreover, we introduce and describe a more complex type of hemocyanin tridecamer discovered in fresh/brackish-water cerithioid snails (Leptoxis, Melanoides, Terebralia). Results The "typical" KLH2 tridecamer is partially hollow, whereas the cerithioid tridecamer is almost completely filled with material; it was therefore termed "mega-hemocyanin". In both types, the staggering angle between adjoining decamers is 36°. The cerithioid tridecamer comprises two typical decamers based on the canonical 400 kDa subunit, flanking a central "mega-decamer" composed of ten unique ~550 kDa subunits. The additional ~150 kDa per subunit substantially enlarge the internal collar complex. Preliminary oxygen binding measurements indicate a moderate hemocyanin oxygen affinity in Leptoxis (p50 ~9 mmHg), and a very high affinity in Melanoides (~3 mmHg) and Terebralia (~2 mmHg). Species-specific and individual variation in the proportions of the two subunit types was also observed, leading to differences in the oligomeric states found in the hemolymph. Conclusions In cerithioid hemocyanin tridecamers ("mega-hemocyanin") the collar complex of the central decamer is substantially enlarged and modified. The preliminary O2 binding curves indicate that there are species-specific functional differences in the cerithioid mega-hemocyanins which might reflect different physiological tolerances of these gill-breathing animals. The observed differential expression of the two subunit types of mega-hemocyanin might allow individual respiratory acclimatization. We hypothesize that mega-hemocyanin is a key character supporting the adaptive radiation and invasive capacity of cerithioid snails.

2010-01-01

204

[Proposed neotype Streptomyces ruber (Krainsky, 1914) Waksman et Henrici, 1948].  

PubMed

Culture 78 was proposed as a neotype of Streptomyces ruber. It was isolated from the soils of the Baikal region and was closest, in its taxonomic properties, to the original description of the species [13] whose representative had been lost. Cultures from different microbial collections designated as S. ruber were shown to be unlike the original description. The neotype had the following taxononic properties: the cell wall of type I; spiral sporophores with extended spirals having 2-3 coils; oval spores with a smooth envelope; greyish pink aerial and dark-red substrate mycelia; a red pigment not passing into the medium; slow gelatin liquefaction and milk peptonization; weak starch hydrolysis; assimilation of glucose, xylose, rammose, fructose, and inositol; weak growth on arabinose, raffinose and mannitol, but not on sucrose; no formation of melanoid pigments; synthesis of riboflavin and prodigiosin pigments; inhibition of Gram-positive bacterial and acid-resistant mycobacterial growth; no inhibition of yeast and fungal growth. The culture was sensitive to streptomycin, neomycin, gentamycin, monomycin, tetracycline,erythromycin, oleandomycin, lincomycin, ristomycin, levomycetin, polymyxin and fusidin, but resistant in penicillin. The population was composed of six variants [3]: main, faded, asporogenic red, asporogenic yellow, asporogenic white and nocardia-like. The latter two were not capable of riboflavin and prodigiosin formation. The asporogenic yellow variant was a monosynthetic organism: it formed riboflavin, but could not synthesize prodigiosin. The neotype of S. ruber 78 is deposited withthe national Collection of Microorganisms (the reference number is VKM A-611). PMID:3613997

Kuznetsov, V D; Filippova, S N; Poltorak, V A

205

Outbreak of Philophthalmus gralli in four greater rheas (Rhea americana).  

PubMed

Using slit-lamp biomicroscopy, conjunctival biopsy, and morphological identification, a flock of four Greater rheas (Rhea americana) in Arizona were diagnosed with conjunctivitis secondary to Philophthalmus gralli (P. gralli) infection. Aquatic snails from the exhibit's water source were identified as Melanoides tuberculatus, a known vector for P. gralli. Comparison of partial sequences of DNA regions from P. gralli adults removed from the rheas and metacercariae from the aquatic snails demonstrated a 100% match, confirming the source of infection. The flock was divided into two treatment groups: the most severely affected rheas received both manual removal of trematodes and praziquantel 1% ointment OU q12?h and the least severely affected rheas were only given praziquantel 1% ointment OU q12?h. The rheas were permanently relocated away from the infected water source and aquatic snails. Initial resolution was seen at 17?weeks in the most severely affected rhea, which had 675 adult P. gralli removed and topical praziquantel. The two rheas that only received topical praziquantel showed resolution within 3 and 15?weeks. Current recommendations for treating P. gralli include: manual removal of trematodes, topical praziquantel 1% ointment, and relocation away from infected water sources and aquatic snails. PMID:22429741

Church, Melanie L; Barrett, Paul M; Swenson, Julie; Kinsella, John M; Tkach, Vasyl V

2012-03-19

206

A Comprehensive Expressed Sequence Tag Linkage Map for Tiger Salamander and Mexican Axolotl: Enabling Gene Mapping and Comparative Genomics in Ambystoma  

PubMed Central

Expressed sequence tag (EST) markers were developed for Ambystoma tigrinum tigrinum (Eastern tiger salamander) and for A. mexicanum (Mexican axolotl) to generate the first comprehensive linkage map for these model amphibians. We identified 14 large linkage groups (125.5–836.7 cM) that presumably correspond to the 14 haploid chromosomes in the Ambystoma genome. The extent of genome coverage for these linkage groups is apparently high because the total map size (5251 cM) falls within the range of theoretical estimates and is consistent with independent empirical estimates. Unlike most vertebrate species, linkage map size in Ambystoma is not strongly correlated with chromosome arm number. Presumably, the large physical genome size (?30 Gbp) is a major determinant of map size in Ambystoma. To demonstrate the utility of this resource, we mapped the position of two historically significant A. mexicanum mutants, white and melanoid, and also met, a quantitative trait locus (QTL) that contributes to variation in metamorphic timing. This new collection of EST-based PCR markers will better enable the Ambystoma system by facilitating development of new molecular probes, and the linkage map will allow comparative studies of this important vertebrate group.

Smith, J. J.; Kump, D. K.; Walker, J. A.; Parichy, D. M.; Voss, S. R.

2005-01-01

207

Holocene lacustrine fluctuations and deep CO2 degassing in the northeastern Lake Langano Basin (Main Ethiopian Rift)  

NASA Astrophysics Data System (ADS)

This work reports the results of an integrated investigation on Holocene faulted deposits exposed on the northeastern Lake Langano in the central sector of the Main Ethiopian Rift (MER). The Lake Langano is part of a closed basin and thus it is highly sensitive to climate fluctuations. The present study explored the foot of the Haroresa escarpment, where coarse-grained slope deposits interbedded with thin lake shore shell-rich coarse sands are well exposed. Stratigraphical analysis of these deposits, integrated with radiocarbon dating carried out on lacustrine gastropod Melanoides tubercolata shells, points to significant lake level fluctuations forced mainly by climate oscillations. These have been interplaying during the early and middle Holocene with a structurally-controlled threshold separating an embayment of the Lake Langano to the south, from the small perched Lake Haro Bu-a basin to the north. Significant differences in the 13C/12C isotopic ratio have been identified in the M. tubercolata shells collected on the opposite sides of such a threshold. The time-space variations of the isotopic signature of the shells are referred to the mutual relationships between the two main different CO2 sources (i.e., microbial activity and deep mantle degassing) dissolved in the lake water.

Benvenuti, Marco; Bonini, Marco; Tassi, Franco; Corti, Giacomo; Sani, Federico; Agostini, Andrea; Manetti, Piero; Vaselli, Orlando

2013-01-01

208

The schistosome intermediate host, Bulinus nyassanus, is a 'preferred' food for the cichlid fish, Trematocranus placodon, at Cape Maclear, Lake Malawi.  

PubMed

Over the last decade, transmission of the schistosome parasites of humans has increased in parts of Lake Malawi, possibly because over-fishing has led to a decline in the numbers of molluscivorous fish. The stomach contents of 51 wild-caught Trematocranus placodon from the Cape Maclear area of Lake Malawi have now been investigated and compared with the field abundance of snail species at two sites, close to where the fish were caught. The snails found in the fish stomachs were identified to genus or species on the basis of their shell fragments and/or opercula. The sizes of the prosobranchs consumed by the T. placodon were determined from their operculum sizes whereas the Bulinus nyassanus ingested by the fish were categorized as small (<4 mm) or large (> or =4 mm) on the basis of their shell fragments. The proportion of the Bu. nyassanus ingested that were categorized as large increased with fish size. Furthermore, the relative abundance of Bu. nyassanus in the guts of the fish was considerably higher than in the field, indicating that the T. placodon had a 'preference' for Bu. nyassanus over the Melanoides species that dominated the snail fauna. Small specimens of Bellamya species were also consumed in a greater proportion than found in field. PMID:16417717

Evers, B N; Madsen, H; McKaye, K M; Stauffer, J R

2006-01-01

209

Low rates of bindin codon evolution in lecithotrophic Heliocidaris sea urchins.  

PubMed

Life-history variables including egg size affect the evolutionary response to sexual selection in broadcast-spawning sea urchins and other marine animals. Such responses include high or low rates of codon evolution at gamete recognition loci that encode sperm- and egg-surface peptides. Strong positive selection on such loci affects intraspecific mating success and interspecific reproductive divergence (and may play a role in speciation). Here, we analyze adaptive codon evolution in the sperm acrosomal protein bindin from a brooding sea urchin (Heliocidaris bajulus, with large eggs and nonfeeding or lecithotrophic larval development) and compare our results to previously published data for two closely related congeners. Purifying selection and low relative rates of bindin nonsynonymous substitution in H. bajulus were significantly different from selectively neutral bindin evolution in H. erythrogramma despite similar large egg size in those two species, but were similar to the background rate of nonsynonymous bindin substitution for other closely related sea urchins (including H. tuberculata, all with small egg size and feeding planktonic larval development). Bindin evolution is not driven by egg size variation among Heliocidaris species, but may be more consistent with an alternative mechanism based on the effects of high or low spatial density of conspecific mates. PMID:22671541

Hart, Michael W; Popovic, Iva; Emlet, Richard B

2012-04-01

210

Some helminth and arthropod parasites of the grey duiker, Sylvicapra grimmia.  

PubMed

Sixteen grey duikers were culled on the farm Riekert 's Laager in the central Transvaal at irregular intervals from May 1979-March 1981. One trematode species, 3 cestode species and 16 nematode species were recovered from these animals. Of these the following are new helminth records for this antelope: Cooperia hungi , Cooperia neitzi , Cooperia pectinata , Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus falculatus , Trichostrongylus instabilis , Impalaia tuberculata , Nematodirus sp. and Paramphistomum sp. In addition, 6 species of ixodid ticks were collected. These, in order of abundance, were Amblyomma hebraeum (55,9%), Rhipicephalus appendiculatus (36,6%), Rhipicephalus evertsi evertsi (5,1%), Boophilus decoloratus (2,3%), Boophilus microplus (0,05%) and Haemaphysalis sp. (0,05%). Only 60 (2,8%) of the 2 118 ticks that were collected were adults. Of the 3 species of lice that were recovered, Linognathus zumpti zumpti was most abundant (58,9%), but, out of a total of 1 498 collected, 1 496 occurred on 1 animal only. Linognathus breviceps constituted 29,5% and Damalinia lerouxi 11,6% of the total. A total of 277 specimens of the hippoboscid fly Lipoptena paradoxa were collected from 12 of the 16 animals examined. Trends in the seasonal fluctuation of Haemonchus, Trichostrongylus, Impalaia , Lipoptena and the immature stages of Amblyomma and R. appendiculatus are graphically illustrated. PMID:6676685

Boomker, J; Du Plessis, W H; Boomker, E A

1983-12-01

211

Classification of Camellia (Theaceae) Species Using Leaf Architecture Variations and Pattern Recognition Techniques  

PubMed Central

Leaf characters have been successfully utilized to classify Camellia (Theaceae) species; however, leaf characters combined with supervised pattern recognition techniques have not been previously explored. We present results of using leaf morphological and venation characters of 93 species from five sections of genus Camellia to assess the effectiveness of several supervised pattern recognition techniques for classifications and compare their accuracy. Clustering approach, Learning Vector Quantization neural network (LVQ-ANN), Dynamic Architecture for Artificial Neural Networks (DAN2), and C-support vector machines (SVM) are used to discriminate 93 species from five sections of genus Camellia (11 in sect. Furfuracea, 16 in sect. Paracamellia, 12 in sect. Tuberculata, 34 in sect. Camellia, and 20 in sect. Theopsis). DAN2 and SVM show excellent classification results for genus Camellia with DAN2's accuracy of 97.92% and 91.11% for training and testing data sets respectively. The RBF-SVM results of 97.92% and 97.78% for training and testing offer the best classification accuracy. A hierarchical dendrogram based on leaf architecture data has confirmed the morphological classification of the five sections as previously proposed. The overall results suggest that leaf architecture-based data analysis using supervised pattern recognition techniques, especially DAN2 and SVM discrimination methods, is excellent for identification of Camellia species.

Lee, Sean; Nitin, Mantri

2012-01-01

212

Predicting water toxicity: pairing passive sampling with bioassays on the Great Barrier Reef.  

PubMed

Many coral reefs worldwide occur adjacent to urban or agricultural land which places these ecosystems at threat of exposure to complex mixtures of pollutants. In this study, the pairing of passive sampler extracts with bioassays is proposed as a tool for predicting effects of organic pollutant mixtures on key biota within coral reef ecosystems. Passive samplers, SDB-RPS Empore disks, which sequester a mixture of the contaminants present in the environment, were deployed at three sites in the Great Barrier Reef (GBR). Extracts from these samplers were analysed for herbicides and applied to bioassays targeting integral life stages or functions of coral reef biota. Biota included scleractinian coral larvae, sea urchin larvae, a marine diatom and marine bacteria. Photosynthesis in the marine diatom Phaeodactylum tricornutum was inhibited at the sampled environmental concentration while an environmental concentration factor of 15 times inhibited luminescence in the marine bacterium Vibrio fischeri. Concentrations of 50 times sampled environmental levels of organic pollutants inhibited >90% of Acropora millepora settlement and 100-fold environmental enrichment inhibited 100% Heliocidaris tuberculata larval development. These results demonstrate the utility of pairing passive sampling with bioassays and reveal that mixtures of organic pollutants in the GBR have the potential to cause detrimental effects to coral reef biota. PMID:19819564

Shaw, Melanie; Negri, Andrew; Fabricius, Katharina; Mueller, Jochen F

2009-09-01

213

Comparative toxicity of chemicals to earthworms  

SciTech Connect

The concentration-response (mortality) relationships of four species of earthworms, Eisenia fetida (Savigny), Allolobophora tuberculata (Eisen), Eudrilus eugeniae (Kinberg), and Perionyx excavatus (Perrier) are summarized for 62 chemicals and two test protocols. A Weibull function is used to summarize these data for each chemical in terms of sensitivity and toxicity, in addition to the LC50. The estimation of the Weibull parameters a and k summarize the entire concentration-response relationship. This technique should be applicable to a variety of testing protocols with different species whenever the goal is summarizing the shape of the concentration-response curves to fully evaluate chemical impact on organisms. In some cases for these data four orders of magnitude separate LC50s of the soil test and the contact test for the same chemical and species. All four species appear to be similar in range of toxicity and tolerance to these chemicals, suggesting that Eisenia fetida and may be representative of these four species and these chemicals.

Callahan, C.A.; Shirazi, M.A. (Environmental Protection Agency, Corvallis, OR (United States)); Neuhauser, E.F. (Niagara Mohawk Power Corp., Syracuse, NY (United States))

1994-02-01

214

Ontogeny of behavioural adaptations in beach crustaceans: some temporal considerations for integrated coastal zone management and conservation  

NASA Astrophysics Data System (ADS)

So-called "typical" behavioural responses of coastal animals to particular stimuli have previously been shown often to vary cyclically in phase with diel or tidal cycles in the environment. Less well-studied are differences in the behaviour of adults and juveniles of the same species at the same time of day or tidal state, or in response to the same stimulus. Experimental studies of such differences in behaviour are reviewed and compared for three species of beach crustaceans, namely, the crab Carcinus maenas, the isopod Eurydice pulchra and the amphipod Orchestoidea tuberculata. Juvenile, but not adult, Carcinus will entrain circatidal rhythmicity after exposure to artificial tidal cycles of immersion/emersion; juvenile, but not adult, Eurydice express pronounced free-running circatidal swimming rhythms at neap tides as well as at springs; and, in Orchestoidea, juveniles and adults express patterns of daily locomotor activity that are complementary, both on the shore and in the laboratory. These ontogenetic differences are discussed in relation to distributional and behavioural differences between adults and juveniles in each species, drawing attention to their adaptive significance and wider implications for coastal management and conservation.

Naylor, E.; Kennedy, F.

2003-10-01

215

Effects of an invasive plant on population dynamics in toads.  

PubMed

When populations decline in response to unfavorable environmental change, the dynamics of their population growth shift. In populations that normally exhibit high levels of variation in recruitment and abundance, as do many amphibians, declines may be difficult to identify from natural fluctuations in abundance. However, the onset of declines may be evident from changes in population growth rate in sufficiently long time series of population data. With data from 23 years of study of a population of Fowler's toad (Anaxyrus [ = Bufo] fowleri) at Long Point, Ontario (1989-2011), we sought to identify such a shift in dynamics. We tested for trends in abundance to detect a change point in population dynamics and then tested among competing population models to identify associated intrinsic and extrinsic factors. The most informative models of population growth included terms for toad abundance and the extent of an invasive marsh plant, the common reed (Phragmites australis), throughout the toads' marshland breeding areas. Our results showed density-dependent growth in the toad population from 1989 through 2002. After 2002, however, we found progressive population decline in the toads associated with the spread of common reeds and consequent loss of toad breeding habitat. This resulted in reduced recruitment and population growth despite the lack of significant loss of adult habitat. Our results underscore the value of using long-term time series to identify shifts in population dynamics coincident with the advent of population decline. Efectos de una Planta Invasora sobre las Dinámica Poblacional de Sapos. PMID:23692126

Greenberg, Daniel A; Green, David M

2013-05-21

216

Phylogeny, floral evolution, and inter-island dispersal in Hawaiian Clermontia (Campanulaceae) based on ISSR variation and plastid spacer sequences.  

PubMed

Previous studies based on DNA restriction-site and sequence variation have shown that the Hawaiian lobeliads are monophyletic and that the two largest genera, Cyanea and Clermontia, diverged from each other ca. 9.7 Mya. Sequence divergence among species of Clermontia is quite limited, however, and extensive hybridization is suspected, which has interfered with production of a well-resolved molecular phylogeny for the genus. Clermontia is of considerable interest because several species posses petal-like sepals, raising the question of whether such a homeotic mutation has arisen once or several times. In addition, morphological and molecular studies have implied different patterns of inter-island dispersal within the genus. Here we use nuclear ISSRs (inter-simple sequence repeat polymorphisms) and five plastid non-coding sequences to derive biparental and maternal phylogenies for Clermontia. Our findings imply that (1) Clermontia is not monophyletic, with Cl. pyrularia nested within Cyanea and apparently an intergeneric hybrid; (2) the earliest divergent clades within Clermontia are native to Kauài, then Òahu, then Maui, supporting the progression rule of dispersal down the chain toward progressively younger islands, although that rule is violated in later-evolving taxa in the ISSR tree; (3) almost no sequence divergence among several Clermontia species in 4.5 kb of rapidly evolving plastid DNA; (4) several apparent cases of hybridization/introgression or incomplete lineage sorting (i.e., Cl. oblongifolia, peleana, persicifolia, pyrularia, samuelii, tuberculata), based on extensive conflict between the ISSR and plastid phylogenies; and (5) two origins and two losses of petaloid sepals, or--perhaps more plausibly--a single origin and two losses of this homeotic mutation, with its introgression into Cl. persicifolia. Our phylogenies are better resolved and geographically more informative than others based on ITS and 5S-NTS sequences and nuclear SNPs, but agree with them in supporting Clermontia's origin on Kauài or some older island and dispersal down the chain subsequently. PMID:23658747

Givnish, Thomas J; Bean, Gregory J; Ames, Mercedes; Lyon, Stephanie P; Sytsma, Kenneth J

2013-05-02

217

Rivaling the World's Smallest Reptiles: Discovery of Miniaturized and Microendemic New Species of Leaf Chameleons (Brookesia) from Northern Madagascar  

PubMed Central

Background One clade of Malagasy leaf chameleons, the Brookesia minima group, is known to contain species that rank among the smallest amniotes in the world. We report on a previously unrecognized radiation of these miniaturized lizards comprising four new species described herein. Methodology/Principal Findings The newly discovered species appear to be restricted to single, mostly karstic, localities in extreme northern Madagascar: Brookesia confidens sp. n. from Ankarana, B. desperata sp. n. from Forêt d'Ambre, B. micra sp. n. from the islet Nosy Hara, and B. tristis sp. n. from Montagne des Français. Molecular phylogenetic analyses based on one mitochondrial and two nuclear genes of all nominal species in the B. minima group congruently support that the four new species, together with B. tuberculata from Montagne d'Ambre in northern Madagascar, form a strongly supported clade. This suggests that these species have diversified in geographical proximity in this small area. All species of the B. minima group, including the four newly described ones, are characterized by very deep genetic divergences of 18–32% in the ND2 gene and >6% in the 16S rRNA gene. Despite superficial similarities among all species of this group, their status as separate evolutionary lineages is also supported by moderate to strong differences in external morphology, and by clear differences in hemipenis structure. Conclusion/Significance The newly discovered dwarf chameleon species represent striking cases of miniaturization and microendemism and suggest the possibility of a range size-body size relationship in Malagasy reptiles. The newly described Brookesia micra reaches a maximum snout-vent length in males of 16 mm, and its total length in both sexes is less than 30 mm, ranking it among the smallest amniote vertebrates in the world. With a distribution limited to a very small islet, this species may represent an extreme case of island dwarfism.

Glaw, Frank; Kohler, Jorn; Townsend, Ted M.; Vences, Miguel

2012-01-01

218

Phylogeny, Floral Evolution, and Inter-Island Dispersal in Hawaiian Clermontia (Campanulaceae) Based on ISSR Variation and Plastid Spacer Sequences  

PubMed Central

Previous studies based on DNA restriction-site and sequence variation have shown that the Hawaiian lobeliads are monophyletic and that the two largest genera, Cyanea and Clermontia, diverged from each other ca. 9.7 Mya. Sequence divergence among species of Clermontia is quite limited, however, and extensive hybridization is suspected, which has interfered with production of a well-resolved molecular phylogeny for the genus. Clermontia is of considerable interest because several species posses petal-like sepals, raising the question of whether such a homeotic mutation has arisen once or several times. In addition, morphological and molecular studies have implied different patterns of inter-island dispersal within the genus. Here we use nuclear ISSRs (inter-simple sequence repeat polymorphisms) and five plastid non-coding sequences to derive biparental and maternal phylogenies for Clermontia. Our findings imply that (1) Clermontia is not monophyletic, with Cl. pyrularia nested within Cyanea and apparently an intergeneric hybrid; (2) the earliest divergent clades within Clermontia are native to Kauài, then Òahu, then Maui, supporting the progression rule of dispersal down the chain toward progressively younger islands, although that rule is violated in later-evolving taxa in the ISSR tree; (3) almost no sequence divergence among several Clermontia species in 4.5 kb of rapidly evolving plastid DNA; (4) several apparent cases of hybridization/introgression or incomplete lineage sorting (i.e., Cl. oblongifolia, peleana, persicifolia, pyrularia, samuelii, tuberculata), based on extensive conflict between the ISSR and plastid phylogenies; and (5) two origins and two losses of petaloid sepals, or—perhaps more plausibly—a single origin and two losses of this homeotic mutation, with its introgression into Cl. persicifolia. Our phylogenies are better resolved and geographically more informative than others based on ITS and 5S-NTS sequences and nuclear SNPs, but agree with them in supporting Clermontia's origin on Kauài or some older island and dispersal down the chain subsequently.

Givnish, Thomas J.; Bean, Gregory J.; Ames, Mercedes; Lyon, Stephanie P.; Sytsma, Kenneth J.

2013-01-01

219

Heavy metal pollution across sites affecting the intestinal helminth communities of the Egyptian lizard, Chalcides ocellatus (Forskal, 1775).  

PubMed

This study aimed to investigate the possible effects of heavy metal pollution across sites and some biological factors on helminth communities infecting the lizard, Chalcides ocellatus. The possibility of heavy metal accumulation by such helminths was also investigated. A total of 202 C. ocellatus were collected from three different sites (industrial, rural, and urban systems) in Ismailia governorate, Egypt, during summer 2009. The lizards were classified according to their sex and size and were examined for the intestinal helminths. Heavy metal levels were detected in the intestinal tissue of the lizards and the recovered helminths. Species richness was 6, 5, and 3 in rural, urban, and industrial systems, respectively. Significant site variations regarding infection prevalence, intensity, and abundance were encountered at different levels. Some noticeable effects of the host size were found. The significant differences found between the metal levels of the intestinal tissues and the recovered helminths and the other relations found in this study may be indications for a possible metals accumulation capacity by helminths. The cestode Oochoristica tuberculata could be a promising biomonitor for Cu and Pb, while the intestinal nematodes were less sensitive to the pollution. Differences in the accumulation capacity may be attributed to the intensity of infection, parasite species, and metal. The observed patterns of distribution and occurrence of helminths and the metals accumulation capacity reflect the need for more studies since this study proposes the model intestinal helminth/C. ocellatus as another promising bioindication system in the terrestrial habitat, especially in areas where the lizard C. ocellatus are available. PMID:22282349

Soliman, M F M

2012-01-27

220

Systematics and molecular phylogeny of the family oscarellidae (homoscleromorpha) with description of two new oscarella species.  

PubMed

The family Oscarellidae is one of the two families in the class Homoscleromorpha (phylum Porifera) and is characterized by the absence of a skeleton and the presence of a specific mitochondrial gene, tatC. This family currently encompasses sponges in two genera: Oscarella with 17 described species and Pseudocorticium with one described species. Although sponges in this group are relatively well-studied, phylogenetic relationships among members of Oscarellidae and the validity of genus Pseudocorticium remain open questions. Here we present a phylogenetic analysis of Oscarellidae using four markers (18S rDNA, 28S rDNA, atp6, tatC), and argue that it should become a mono-generic family, with Pseudocorticium being synonymized with Oscarella, and with the transfer of Pseudocorticium jarrei to Oscarella jarrei. We show that the genus Oscarella can be subdivided into four clades, each of which is supported by either a small number of morphological characters or by molecular synapomorphies. In addition, we describe two new species of Oscarella from Norwegian fjords: O. bergenensis sp. nov. and O. nicolae sp. nov., and we compare their morphology, anatomy, and cytology with other species in this genus. Internal anatomical characters are similar in both species, but details of external morphology and particularly of cytological characters provide diagnostic features. Our study also confirms that O. lobularis and O. tuberculata are two distinct polychromic sibling species. This study highlights the difficulties of species identification in skeleton-less sponges and, more generally, in groups where morphological characters are scarce. Adopting a multi-marker approach is thus highly suitable for these groups. PMID:23737959

Gazave, Eve; Lavrov, Dennis V; Cabrol, Jory; Renard, Emmanuelle; Rocher, Caroline; Vacelet, Jean; Adamska, Maja; Borchiellini, Carole; Ereskovsky, Alexander V

2013-05-30

221

Hyperparasitism of the cryptoniscid isopod Liriopsis pygmaea on the lithodid Paralomis granulosa from the Beagle Channel, Argentina.  

PubMed

A total of 29,570 false king crab Paralomis granulosa were sampled from the Beagle Channel (54 degrees 51'S, 68 degrees 12'W), Tierra del Fuego, Argentina, between July 1996 and August 1998. Crab size varied from 6.8 to 111.2 mm carapace length (CL). A few crabs parasitized by the rhizocephalan Briarosaccus callosus were found; prevalences of externae (the rhizocephalan reproductive body) and scars (the mark left on the host after the death of the parasite) were 0.28 and 0.16%, respectively. Of 85 externae examined, 55 were non-ovigerous and 30 ovigerous. The cryptoniscid isopod Liriopsis pygmaea infested 36.5% of the B. callosus examined. The most abundant stage was the cryptonicus larva, accounting for 208 of the 238 L. pygmaea recovered. Cryptonisci showed a highly aggregated distribution. A total of 92.7% of cryptonicsci were recovered inside empty externae, suggesting that the latter were attractive to cryptonisci. Early subadult females of L. pygmaea were rare; only 3 individuals occurred inside 1 ovigerous externa. Eight late subadult and 18 adult females were found on 3 and 7 non-ovigerous externae, respectively; in addition, 1 aberrant late subadult was found on 1 ovigerous externa. In the Beagle Channel, the population of P. granulosa harbours 3 different parasites: the bopyrid isopod Pseudione tuberculata, which reaches highest prevalence at 10 to 20 mm CL, the rhizocephalan B. callosus, with highest prevalence at 20 to 40 mm CL, and the cryptoniscid isopod L. pygmaea, which mainly infests rhizocephalan on crabs >40 mm CL. PMID:15038454

Lovrich, Gustavo A; Roccatagliata, Daniel; Peresan, Laura

2004-01-28

222

The helminth parasites of various artiodactylids from some South African nature reserves.  

PubMed

The helminth species composition and helminth burdens of 4 grey duikers, 12 bushbuck, 2 nyala, 2 giraffe, a steenbok, an oribi, a waterbuck and a tsessebe from the Kruger National Park (KNP); of a steenbok and a greater kudu from the farm Riekerts Laager, Transvaal; of a single blue duiker from the Tsitsikama Forest National Park, and of a blue wildebeest, a red hartebeest, a gemsbok and 2 springbok from the Kalahari Gemsbok National Park (KGNP) were collected, counted and identified. New parasite records are: Agriostomum equidentatum from the gemsbok, Cooperia neitzi from the bushbuck, Cooperia sp. from the gemsbok and the red hartebeest, Cooperia yoshidai from the waterbuck and the tsessebe, Dictyocaulus viviparus from the bushbuck, Haemonchus bedfordi from the waterbuck, Haemonchus contortus from the gemsbok, Haemonchus krugeri from the steenbok from the KNP, Impalaia nudicollis from the gemsbok and the red hartebeest, Impalaia tuberculata from the oribi and the waterbuck, Impalaia spp. from the kudu, Longistrongylus meyeri from the steenbok from Riekerts Laager and the gemsbok, Longistrongylus sabie from the steenbok from the KNP, Longistrongylus schrenki from the tsessebe, Parabronema sp. from the tsessebe and the red hartebeest, Paracooperia serrata from the gemsbok and the steenbok from the KGNP, Pneumostrongylus calcaratus from the bushbuck, Strongyloides sp. from the gemsbok, Trichostrongylus sp. from the gemsbok, the red hartebeest and the steenbok from the KGNP, Trichostrongylus axei from the blue duiker, Trichostrongylus falculatus from the bushbuck and the oribi, Trichostrongylus instabilis from the bushbuck, the steenbok from the KNP and the oribi and Trichostrongylus thomasi from the grey duikers and tsessebe. Host specificity of the parasites was not marked and crossinfestation was common. This was not true for the giraffe, since none of the helminths of these animals were found in the antelope and vice versa. PMID:3725333

Boomker, J; Horak, I G; De Vos, V

1986-06-01

223

Patterns of litter disappearance in a northern hardwood forest invaded by exotic earthworms.  

PubMed

A field study was conducted to evaluate the effects of exotic earthworm invasions on the rates of leaf litter disappearance in a northern hardwood forest in southcentral New York, USA. Specifically, we assessed whether differences in litter quality and the species composition of exotic earthworm communities affected leaf litter disappearance rates. Two forest sites with contrasting communities of exotic earthworms were selected, and disappearance rates of sugar maple and red oak litter were estimated in litter boxes in adjacent earthworm-free, transition, and earthworm-invaded plots within each site. After 540 days in the field, 1.7-3 times more litter remained in the reference plots than in the earthworm-invaded plots. In the earthworm-invaded plots, rates of disappearance of sugar maple litter were higher than for oak litter during the first year, but by the end of the experiment, the amount of sugar maple and oak litter remaining in the earthworm-invaded plots was identical within each site. The composition of the earthworm communities significantly affected the patterns of litter disappearance. In the site dominated by the anecic earthworm Lumbricus terrestris and the endogeic Aporrectodea tuberculata, the percentage of litter remaining after 540 days (approximately 17%) was significantly less than at the site dominated by L. rubellus and Octolasion tyrtaeum (approximately 27%). This difference may be attributed to the differences in feeding behavior of the two litter-feeding species: L. terrestris buries entire leaves in vertical burrows, whereas L. rubellus usually feeds on litter at the soil surface, leaving behind leaf petioles and veins. Our results showed that earthworms not only accelerate litter disappearance rates, but also may reduce the differences in decomposition rates that result from different litter qualities at later stages of decay. Similarly, our results indicate that earthworm effects on decomposition vary with earthworm community composition. Furthermore, because earthworm invasion can involve a predictable shift in community structure along invasion fronts or through time, the community dynamics of invasion are important in predicting the spatial and temporal effects of earthworm invasion on litter decomposition, especially at later stages of decay. PMID:16705969

Suárez, Esteban R; Fahey, Timothy J; Yavitt, Joseph B; Groffman, Peter M; Bohlen, Patrick J

2006-02-01

224

Australian gall-inducing scale insects on Eucalyptus: revision of Opisthoscelis Schrader (Coccoidea, Eriococcidae) and descriptions of a new genus and nine new species  

PubMed Central

Abstract We revise the genus Opisthoscelis Schrader, and erect the genus Tanyscelis gen. n. with Opisthoscelis pisiformis Froggatt as its type species. Species of both genera induce sexually dimorphic galls on Eucalyptus (Myrtaceae) in Australia, with Opisthoscelis subrotunda Schrader also in Papua New Guinea. We synonymise the following taxa (junior synonym with senior synonym): Opisthoscelis fibularis Froggatt, syn. n. with Opisthoscelis spinosa Froggatt; Opisthoscelis recurva Froggatt, syn. n. with Opisthoscelis maculata Froggatt; Opisthoscelis globosa Froggatt, syn. n. (= Opisthoscelis ruebsaameni Lindinger) with Opisthoscelis convexa Froggatt; and Opisthoscelis mammularis Froggatt, syn. n. with Opisthoscelis verrucula Froggatt. We transfer seven Opisthoscelis species to Tanyscelis as Tanyscelis conica (Fuller), comb. n., Tanyscelis convexa (Froggatt), comb. n., Tanyscelis maculata (Froggatt), comb. n., Tanyscelis maskelli (Froggatt), comb. n., Tanyscelis pisiformis (Froggatt), comb. n., Tanyscelis spinosa (Froggatt), comb. n., and Tanyscelis verrucula (Froggatt), comb. n. We redescribe and illustrate the adult female of each named species of Opisthoscelis for which the type material is known, as well as the first-instar nymph of the type species of Opisthoscelis (Opisthoscelis subrotunda) and Tanyscelis (Opisthoscelis pisiformis). We describe four new species of Opisthoscelis: Opisthoscelis beardsleyi Hardy & Gullan, sp. n., Opisthoscelis thurgoona Hardy & Gullan, sp. n., Opisthoscelis tuberculataHardy & Gullan, sp. n., and Opisthoscelis ungulifinis Hardy & Gullan, sp. n., and five new species of Tanyscelis: Tanyscelis grallator Hardy & Gullan, sp. n., Tanuscelis megagibba Hardy & Gullan, sp. n., Tanyscelis mollicornuta Hardy & Gullan, sp. n., Tanyscelis tripocula Hardy & Gullan, sp. n., and Tanyscelis villosigibba Hardy & Gullan, sp. n. We designate lectotypes for Opisthoscelis convexa, Opisthoscelis fibularis, Opisthoscelis globosa Froggatt, Opisthoscelis maculata, Opisthoscelis mammularis, Opisthoscelis maskelli, Opisthoscelis pisiformis, Opisthoscelis recurva, Opisthoscelis serrata, Opisthoscelis spinosa, and Opisthoscelis verrucula. As a result of our taxonomic revision, Opisthoscelis has six species and Tanyscelis has 12 species. We describe the galls of females for all 18 species and galls of males for 10 species of Opisthoscelis and Tanyscelis, and provide photographs of the galls for most species. A key to the adult females of the species of both genera is included.

Hardy, Nate B.; Gullan, Penny J.

2010-01-01

225

HUMAN PULMONARY DISTOMIASIS CAUSED BY PARAGONIMUS WESTERMANNI  

PubMed Central

1. The morbidity of pulmonary distomiasis among the school children in the plains of the Prefecture of Shinchiku is 4.3 per cent, while in the mountainous regions among the savages it reaches in some districts 50 per cent. 2. Seventeen species of cercariæ were discovered in fresh water mollusks in the Prefecture of Shinchiku, Formosa. But it was impossible to ascertain from morphological characteristics alone which of them developed into the pulmonary fluke. Consequently, the eggs of the pulmonary fluke after hatching into miracidia were allowed to come into contact with several species of fresh water mollusks, of which they infected two. But as it was difficult to keep the two spedes alive in the aquarium long enough to get cercariæ, the second intermediate hosts of the pulmonary distomas were looked for in the severely infected villages of the savage tribes. 3. The miracidia of the pulmonary distomas leave the egg about 4 weeks after they are first set free in the water, and if they do not reach mollusks they soon die. 4. Three species of fresh water mollusks were found to act as the first intermediate host of the pulmonary distomas; viz., Melania libertina Gould, Melania tuberculata Mueller, and Melania obliquegranosa Smith. 5. The cercariæ of the pulmonary distoma may be identified by their small size and a spine in the oral sucker. They develop in the liver of the three spedes of Melania mentioned above. 6. The second intermediate hosts of the pulmonary distoma,detected in the Prefecture of Shinchiku, are the following three species of fresh water crabs: Potamon (Geothelphusa) obtusipes Stimpson (native name, red crab), Potamon (Geothelphusa) dehaanii White (native name, dung crab), and Eriocheir japonicus De Haan (native name, hairy crab). In addition it was discovered that the following two species might act as intermediate hosts: Sesarma dehaanii Milne-Edwards and Potamon (Parathelphusa) sinensis Milne-Edwards. In Formosa four of the five species are the carriers of the cercariæ. 7. The encysted cercariæ are found in the gills, liver, and muscle, and have an elongated dark excretory vesicle in the middle of their bodies. They resemble the adult flukes. 8. Full grown encysted cercariæ fed to dogs develop into mature pulmonary distomas and begin to lay eggs in about 90 days. 9. In the final host the parasites are taken into the alimentary canal as encysted cercariæ. They liberate themselves from the cysts in the intestine and bore through the jejunum into the abdominal cavity. They then pierce the diaphragm, enter the thoracic cavity, and piercing the pleura reach the lungs. In the parenchyma of the lungs they form cysts and develop into adult forms. 10. The chief causes of pulmonary distomiasis are the eating of raw or insufficiently cooked crabs infected with the cercariæ of Paragonimus westermanni, and the drinking of river water containing them.

Nakagawa, Koan

1917-01-01