Dispersal and survival of Anopheles funestus and A. gambiae s.l. (Diptera: Culicidae) during the rainy season in southeast Tanzania

1998 ◽  
Vol 88 (5) ◽  
pp. 561-566 ◽  
Author(s):  
W. Takken ◽  
J.D. Charlwood ◽  
P.F. Billingsley ◽  
G. Gort
Keyword(s):  
Rainy Season ◽  
Light Trap ◽  
Survival Rates ◽  
Anopheles Funestus ◽  
The Other ◽  
Movement Rates ◽  
Fluorescent Powder ◽  
Local Topography ◽  
Release Area ◽  
Species Specific

AbstractIn a rural area of southeastern Tanzania, studies were undertaken on the dispersal and survival of Anopheles funestus Giles and A. gambiae Giles s.l. during the rainy season. Blood fed, resting mosquitoes were collected indoors, marked with fluorescent powder and released on the same day from two different sites in the study area. For two weeks indoor resting mosquitoes were collected from 11 houses in the release area. Additional collections were made with a light trap from a sentinel house in the centre of the study area. Anopheles funestus was more abundant than A. gambiae s.l. Of 4262 A. funestus and 645 A. gambiae s.l. released, 4.3% and 7.4%, respectively, were recaptured. Dispersal of mosquitoes was not random: one of three areas was favoured significantly more than the other areas, as shown by the recapture and movement rates of marked mosquitoes. Based on the regression of the recapture rate, estimated daily survival rates of A. funestus and A. gambiae s.l. were 0.63 and 0.78, respectively. These were significantly different. The differences in dispersal and survival rates between the two species are discussed in view of local topography and species-specific characteristics.

Sampling Anopheles arabiensis, A. gambiae sensu lato and A. funestus (Diptera: Culicidae) with CDC light-traps near a rice irrigation area and a sugarcane belt in western Kenya

1994 ◽  
Vol 84 (3) ◽  
pp. 319-324 ◽  
Author(s):  
A.K. Githeko ◽  
M.W. Service ◽  
C.M. Mbogo ◽  
F.A. Atieli ◽  
F.O. Juma
Keyword(s):  
Anopheles Arabiensis ◽  
Communicable Disease ◽  
Light Trap ◽  
Anopheles Funestus ◽  
Malaria Vectors ◽  
Light Traps ◽  
Western Kenya ◽  
Specific Variation ◽  
Species Specific ◽  
Center Light

AbstractCDC (Communicable Disease Center) light-traps were compared with human-bait collections as an alternative method for sampling malaria vectors in two villages of western Kenya. The numbers of Anopheles funestus Giles and Anopheles gambiae sensu lato Giles in CDC light-trap collections were significantly correlated to the numbers caught in human-bait collections, but in Anopheles arabiensis Patton the two collections were not significantly correlated. Most of the female vectors collected in the traps were unfed. Parity of A. arabiensis collected in CDC light-traps (44.3%) was significantly lower than the rate obtained from females caught on human-bait (54.5%). Although CDC light-traps provide a cheap and convenient method for collecting vectors, further studies should nevertheless be undertaken to determine the influence of species-specific variation in the sizes and age-structure of collections because such variations can affect the epidemiological interpretation of the data.

scholarly journals Prebiotic Combinations Effects on the Colonization of Staphylococcal Skin Strains

2020 ◽  
Vol 9 (1) ◽  
pp. 37
Author(s):  
Silvia Di Lodovico ◽  
Franco Gasparri ◽  
Emanuela Di Campli ◽  
Paola Di Fermo ◽  
Simonetta D’Ercole ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Commensal Bacteria ◽  
The Other ◽  
Bacteriostatic Effect ◽  
Skin Microbiota ◽  
Relevant Effect ◽  
Planktonic Phase ◽  
Species Specific ◽  
Biomass Quantification ◽  
General Reduction

Background: An unbalanced skin microbiota due to an increase in pathogenic vs. commensal bacteria can be efficiently tackled by using prebiotics. The aim of this work was to identify novel prebiotic combinations by exerting species-specific action between S. aureus and S. epidermidis strains. Methods: First, the antimicrobial/antibiofilm effect of Xylitol-XYL and Galacto-OligoSaccharides–GOS combined with each other at different concentrations (1, 2.5, 5%) against S. aureus and S. epidermidis clinical strains was evaluated in time. Second, the most species-specific concentration was used to combine XYL with Fructo-OligoSaccharides–FOS, IsoMalto-Oligosaccharides–IMO, ArabinoGaLactan–LAG, inulin, dextran. Experiments were performed by OD600 detection, biomass quantification and LIVE/DEAD staining. Results: 1% XYL + 1% GOS showed the best species-specific action with an immediate antibacterial/antibiofilm action against S. aureus strains (up to 34.54% ± 5.35/64.68% ± 4.77) without a relevant effect on S. epidermidis. Among the other prebiotic formulations, 1% XYL plus 1% FOS (up to 49.17% ± 21.46/37.59% ± 6.34) or 1% IMO (up to 41.28% ± 4.88/36.70% ± 10.03) or 1% LAG (up to 38.21% ± 5.31/83.06% ± 5.11) showed antimicrobial/antibiofilm effects similar to 1% XYL+1% GOS. For all tested formulations, a prevalent bacteriostatic effect in the planktonic phase and a general reduction of S. aureus biofilm formation without loss of viability were recorded. Conclusion: The combinations of 1% XYL with 1% GOS or 1% FOS or 1% IMO or 1% LAG may help to control the balance of skin microbiota, representing good candidates for topic formulations.

scholarly journals Species-Specific Segregation of Gender-Associated Mitochondrial DNA Types in an Area Where Two Mussel Species (Mytilus edulis and M. trossulus) Hybridize

Genetics ◽  
1996 ◽  
Vol 143 (3) ◽  
pp. 1359-1367 ◽  
Author(s):  
Carlos Saavedra ◽  
Donald T Stewart ◽  
Rebecca R Stanwood ◽  
Eleftherios Zouros
Keyword(s):  
Mytilus Edulis ◽  
The Other ◽  
Allozyme Analysis ◽  
Mussel Species ◽  
Species Origin ◽  
Species Pairs ◽  
Nuclear Background ◽  
Species Specific ◽  
Dna Types ◽  
Fertile Hybrids

Abstract In each of the mussel species Mytilus edulis and M. trossulus there exist two types of mtDNA, the F type transmitted through females and the M type transmitted through males. Because the two species produce fertile hybrids in nature, F and M types of one may introgress into the other. We present the results from a survey of a population in which extensive hybridization occurs between these two species. Among specimens classified as “pure” M. edulis or “pure” M. trossulus on the basis of allozyme analysis, we observed no animal that carried the F or the M mitotype of the other species. In most animals of mixed nuclear background, an individual's mtDNA came from the species that contributed the majority of the individual's nuclear genes. Most importantly, the two mtDNA types in post-F1 male hybrids were of the same species origin. We interpret this to mean that there are intrinsic barriers to the exchange of mtDNA between these two species. Because such barriers were not noted in other hybridizing species pairs (many being even less interfertile than M. edulis and M. trossulus), their presence in Mytilus could be another feature of the unusual mtDNA system in this genus.

scholarly journals Salinity and freshwater discharge determine rotifer distribution at the Mossoró River Estuary (Semiarid Region of Brazil)

2010 ◽  
Vol 70 (3) ◽  
pp. 551-557 ◽  
Author(s):  
AMA. Medeiros ◽  
JEL. Barbosa ◽  
PR. Medeiros ◽  
RM. Rocha ◽  
LF. Silva
Keyword(s):  
Species Richness ◽  
Rainy Season ◽  
Salinity Gradient ◽  
River Estuary ◽  
Positive Influence ◽  
Freshwater Discharge ◽  
The Other ◽  
Semiarid Region ◽  
Inverse Estuary ◽  
Species Richness And Abundance

The present study aimed at evaluating differences in rotifer distribution in three estuarine zones in an inverse estuary located in the Semiarid Region of Brazil. Zones were chosen based on their proximity to the ocean and river border as a means of reflecting a horizontal salinity gradient. High freshwater discharge during the rainy season was the major determinant of rotifer composition. On the other hand, due to higher salinity values during the dry season, very low values of species richness and abundance were observed in all zones. Therefore, the study highlights the constraints of salinity and the positive influence of seasonality and river proximity on rotifer species in a semiarid estuarine environment.

scholarly journals Bluetongue virus in a Nigerian dairy cattle herd: 1. Serological studies and correlation of virus activity to vector population

1983 ◽  
Vol 90 (2) ◽  
pp. 177-193 ◽  
Author(s):  
K. A. J. Herniman ◽  
J. P. T. Boorman ◽  
W. P. Taylor
Keyword(s):  
Bluetongue Virus ◽  
Light Trap ◽  
Survival Rates ◽  
Virus Transmission ◽  
Neutralizing Antibody ◽  
Decay Rates ◽  
Vector Population ◽  
Virus Activity ◽  
Serological Studies ◽  
Trap Catches

SUMMARYNewborn calves were bled at monthly intervals and examined for serum antibodies to bluetongue virus (BTV). Maternal immunity persisted for 3 months and it was possible to calculate decay rates for virus neutralizing antibody. Calves were subclinically infected with BTV within a few months of becoming susceptible and neutralization tests were used to deduce the serotype responsible. A profile of virus activity was built up over a 12 month period. Frequent light trap catches were used to examine the population dynamics of suspected Culicoides vector species. Two species, imicola and schultzei were present throughout the wet and dry seasons and survival rates were sufficiently long to account for virus transmission at any time of the year.

Vocal Learning of Japanese and Rhesus Monkeys

Behaviour ◽  
1989 ◽  
Vol 109 (3-4) ◽  
pp. 191-199 ◽  
Author(s):  
Nobuo Masataka ◽  
Kazuo Fujita
Keyword(s):  
Rhesus Monkeys ◽  
Japanese Monkey ◽  
Species Difference ◽  
Vocal Learning ◽  
The Other ◽  
Playback Experiments ◽  
Biological Mothers ◽  
Japanese Monkeys ◽  
The Cross ◽  
Species Specific

AbstractForaging vocalizations given by Japanese and rhesus momkeys reared by their biological mothers differed from each other in a single parameter. Calls made by a Japanese monkey fostered by a rhesus female were dissimilar to those of conspecifics reared by their biological mothers, but similar to those of rhesus monkeys reared by their biological mothers, and the vocalizations given by rhesus monkeys fostered by Japanese monkey mothers were dissimilar to those of conspecifics reared by their biological mothers, but similar to those of Japanese monkeys reared by their biological mothers. Playback experiments revealed that both Japanese and rhesus monkeys distinguished between the calls of Japanese monkeys reared by their biological mothers and of the cross-fostered rhesus monkeys on one hand, and the vocalizations of rhesus monkeys reared by their biological mothers and of the cross-fostered Japanese monkey on the other hand. Thus, production of species-specific vocalizations was learned by each species, and it was the learned species-difference which the monkeys themselves discriminated.

scholarly journals Biology of the Wild SilkmothAnaphe panda(Boisduval) in the Kakamega Forest of Western Kenya

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
N. Mbahin ◽  
S. K. Raina ◽  
E. N. Kioko ◽  
J. M. Mueke
Keyword(s):  
Life Cycle ◽  
Incubation Period ◽  
Rainy Season ◽  
Dry Season ◽  
Developmental Period ◽  
The Other ◽  
Western Kenya ◽  
Kakamega Forest ◽  
Pupal Period ◽  
Indigenous Forest

A study on the life cycle of the silkmothAnaphe panda(Boisduval) was conducted in two different habitats of the Kakamega Forest in western Kenya: Ikuywa, an indigenous forest, and Isecheno, a mixed indigenous forest. Eggs were laid in clusters, and the incubation period ranged from 40 to 45 days. Larvae fed onBridelia micrantha(Hochst) and passed through seven instars. The developmental period took between 83 to 86 days in the dry season and 112 to118 days in the rainy season. The pupal period ranged between 158 and 178 days in the rainy season and, on the other hand, between 107 and 138 days in the dry season. But the later caught up in development with those that formed earlier. Moths emerged from mid-October until mid-May. Longevity of adultAnaphe pandamoths took between 4 and 6 days, but generally females seemed to live longer than males. The moth also seems to have higher lifespan in the indigenous forest compared to the mixed indigenous forest.

scholarly journals Effect of NaCl on seed germination in some Centaurium Hill. Species (Gentianaceae)

2007 ◽  
Vol 59 (3) ◽  
pp. 227-231 ◽  
Author(s):  
S. Zivkovic ◽  
M. Devic ◽  
B. Filipovic ◽  
Z. Giba ◽  
D. Grubisic
Keyword(s):  
Life History ◽  
Salt Tolerance ◽  
Seed Germination ◽  
Gibberellic Acid ◽  
White Light ◽  
The Other ◽  
Distilled Water ◽  
Nacl Concentration ◽  
History Of ◽  
Species Specific

The influence of high NaCl concentrations on seed germination in both light and darkness was examined in the species Centaurium pulchellum, C. erythraea, C. littorale, C. spicatum, and C. tenuiflorum. Salt tolerance was found to depend on the life history of the seeds. To be specific, seeds of all five species failed to complete germination when exposed to continuous white light if kept all the time in the presence of 100-200 mM and greater NaCl concentrations. However, when after two weeks NaCl was rinsed from the seeds and the seeds were left in distilled water under white light for an additional two weeks, all species completed germination to a certain extent. The percent of germination not only depended on NaCl concentration in the prior medium, but was also species specific. Thus, seeds of C. pulchellum, C. erythraea, and C. littorale completed germination well almost irrespective of the salt concentration previously experienced. On the other hand, seeds of C. tenuiflorum completed germination poorly if NaCl concentrations in the prior media were greater than 200 mM. When seeds after washing were transferred to darkness for an additional 14 days, they failed to complete germination if previously imbibed on media containing NaCl concentrations greater than 400 mM. However, the seeds of all species, even if previously imbibed at 800 mM NaCl, could be induced to complete germination in darkness by 1 mM gibberellic acid. .

scholarly journals Repeated evolution of asymmetric genitalia and right-sided mating behavior in theDrosophila nannopteraspecies group

2019 ◽  
Author(s):  
Andrea Acurio ◽  
Flor T. Rhebergen ◽  
Sarah Paulus ◽  
Virginie Courtier-Orgogozo ◽  
Michael Lang
Keyword(s):  
Related Species ◽  
Current Data ◽  
The Other ◽  
Genital Morphology ◽  
Closely Related Species ◽  
Outgroup Species ◽  
Repeated Evolution ◽  
Drosophila Pachea ◽  
Species Specific ◽  
Group Species

AbstractBackgroundMale genitals have repeatedly evolved left-right asymmetries, and the causes of such evolution remain unclear. TheDrosophila nannopteragroup contains four species, among which three exhibit left-right asymmetries of distinct genital organs. In the most studied species,Drosophila pachea, males display asymmetric genital lobes and they mate right-sided on top of the female. Copulation position of the other species is unknown.ResultsTo assess whether the evolution of genital asymmetry could be linked to the evolution of one-sided mating, we examined phallus morphology and copulation position inD. pacheaand closely related species. The phallus was found to be symmetric in all investigated species exceptD. pachea, which display an asymmetric phallus with a right-sided gonopore, andD. acanthoptera, which harbor an asymmetrically bent phallus. In all examined species, males were found to position themselves symmetrically on top of the female, except inD. pacheaandD. nannoptera, where males mated right-sided, in distinctive, species-specific positions. In addition, the copulation duration was found to be increased innannopteragroup species compared to closely related outgroup species.ConclusionOur study shows that gains, and possibly losses, of asymmetry in genital morphology and mating position have evolved repeatedly in thenannopteragroup. Current data does not allow us to conclude whether genital asymmetry has evolved in response to changes in mating position, or vice versa.

scholarly journals Some like it hot: A differential response to changing temperatures by the malaria vectors Anopheles funestus and An. gambiae s.l.

2016 ◽  
Author(s):  
Jacques D Charlwood
Keyword(s):  
Air Temperature ◽  
Light Trap ◽  
Anopheles Funestus ◽  
Malaria Vectors ◽  
Effect Of Temperature ◽  
Night Time ◽  
Environmental Correlations ◽  
Air Temperatures ◽  
Soil Temperatures ◽  
Gravid Females

Background: With the possible implications of global warming, the effect of temperature on the dynamics of malaria vectors in Africa has become a subject of increasing interest. Information from the field is, however, relatively sparse. We describe the effect of ambient temperature over a five-year period on the dynamics of An. funestus and An. gambiae s.l., collected from a single village in southern Mozambique where temperatures varied from a night-time minimum of 6oC in the cool season to a daytime maximum of 35oC in the hot season. Results: Mean daily air temperatures varied from 34o C to 20oC and soil temperatures varied from 26 o C to 12 o C. Diurnal variation was greatest in the cooler months of the year and were greater in air temperatures than soil temperatures. During the study 301, 705 female An. funestus were collected in 6043 light-trap collections, 161, 466 in 7397 exit collections and 16, 995 in 1315 resting collections. The equivalent numbers for An. gambiae s.l. are 72, 475 in light-traps, 33, 868 in exit collections and 5, 333 from indoor resting collections. Numbers of mosquito were greatest in the warmer months. Numbers of An. gambiae s.l. went through a one hundredfold change (from a mean of 0.14 mosquitoes a night to 14) whereas numbers of An. funestus merely doubled (from a mean of 20 to 40 a night). The highest environmental correlations and mosquito numbers were between mean air temperature (r2 = 0.52 for An. funestus and 0.77 for An. gambiae s.l.). Numbers of mosquito collected were not related to rainfall with lags of up to four weeks. Numbers of both gravid and unfed An. gambiae complex females in exit collections continued to increase at all temperatures recorded but gravid females of An. funestus decreased at temperatures above 28oC. Overall the numbers of gravid and unfed An. funestus collected in exit collections were not correlated (p = 0.07). For an unknown reason the number of An. gambiae s.l. fell below monitoring thresholds during the study. Conclusions: Mean air temperature was the most important environmental parameter affecting both vectors in this part of Mozambique. Numbers of An. gambiae s.l. increased at all temperatures recorded whilst An. funestus appeared to be adversely affected by temperatures of 28oC and above. These differences may influence the distribution of the vectors as the planet warms.

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