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salivary secretion in wild glossina pallidipes austen. (diptera, glossinidae).the salivation behaviour of wild g. pallidipes obtained from lambwe valley and kbwezi was studied. salivation was measured by counting the number of salivary drops secreted per minute and measuring the sizes of the stained saliva after drawing them with a camera lucida. the results confirmed observations obtained from laboratory bred flies. the quantity of saliva secreted by tsetse flies was significantly increased as the flies became hungrier. the proportion of flies salivating also increased w ...197614492
the abundance of pathogenic african trypanosomes in the salivary secretions of wild glossina pallidipes.trypanosome infection rates in wild glossina pallidipes from the lambwe valley, kenya, were determined using salivation and fly dissection methods. of the 416 flies examined by salivation, one was infected with trypanosoma brucei, seven with t. congolense, 18 with t. vivax and three with both t. congolense and t. vivax. the fly infected with t. brucei always secreted saliva heavily infected with trypanosomes. flies infected with t. vivax secreted saliva which contained very few trypanosomes and ...1979539858
vector competence of glossina pallidipes and g. morsitans centralis for trypanosoma vivax, t. congolense and t. b. brucei.vector competence of glossina pallidipes for pathogenic trypanosoma species was compared to that of g. morsitans centralis. cattle or goats were the hosts used to infect teneral tsetse, rabbits were used to maintain tsetse which were dissected on day 30. mean infection rates of g. pallidipes and g. m. centralis by t. vivax isolated from a cow in kenya were respectively 39.5 +/- 8.9% and 32.1 +/- 10.3% whilst for t. vivax isolated from a cow in nigeria, they were 30.0 +/- 7.5% and 19.8 +/- 4.3%. ...19921359753
a comparison of colony performance of glossina pallidipes originating from two allopatric populations in kenya. 19921463909
responses of tsetse to ox sebum: a video study in the field.the behaviour of tsetse (mainly glossina pallidipes austen) around odour-baited targets, with or without a coating of ox sebum, was recorded in the field using video. the addition of sebum increased the total time a fly was in contact with the target, as well as the time spent flying around and landing on it. when carbon dioxide was released as part of the attractant odour plume, the presence of sebum on the target increased the number of landings made by each fly, but did not significantly affe ...19911768897
development of a low-cost tsetse trap and odour baits for glossina pallidipes and g. longipennis in kenya.experiments were carried out to improve the ng2b tsetse trap (brightwell et al., 1987), baited with acetone and cow urine, for use by rural communities to control g.pallidipes austen and g.longipennis corti. modifications included a lower dose rate of acetone, a new cage design and raising the trap about 15-20 cm. research on different trap cone materials showed that the degree of light transmission of the netting, rather than its colour, was the crucial factor affecting the catch of g.pallidipe ...19911768909
vector population responses to control interventions.in 1981, kenyan authorities attempted eradication of tsetse (glossina pallidipes) from the lambwe valley, by sequential aerial spraying of endosulfan. fly populations were reduced by over 99.9% in the main habitats, but recovered to their original levels within one year. in 1986, an argentine research team attempted local elimination of domestic triatominae (triatoma infestans) in an area of santiago del estero. house infestation rates were reduced to an apparent zero, but recovered to pre-contr ...19911793271
recombinant dna probes reveal simultaneous infection of tsetse flies with different trypanosome species.the utility of recombinant dna probes in the detection of natural trypanosome infection of tsetse flies has been assessed in lambwe valley, near the shores of lake victoria, kenya. the tsetse flies were surveyed during two different seasons in 1988. three different probes used each contained highly repetitive dna sequences specific for a species or subspecies of trypanosomes of the nanomonas subgenus. a fourth probe contained repetitive sequences common to trypanosome species of the trypanozoon ...19902362604
effect of host odours on trap catch composition of glossina pallidipes in kenya.the effect of odour attractants on the composition of samples of glossina pallidipes austen was investigated by comparing the age and nutritional status of flies caught in unbaited biconical traps with those caught in traps baited with cow urine and acetone. for both male and female flies, baited traps caught more flies with significantly higher fat content than did unbaited traps. thus the samples from baited traps were more representative of the population as a whole: males showed a fuller ran ...19892519676
responses of tsetse flies (glossina spp.) to compounds on the skin surface of an ox: a laboratory study.the behaviour of male glossina morsitans morsitans westwood and glossina pallidipes austen (diptera: glossinidae) alighting on targets with or without ox sebum was compared. the presence of ox sebum did not increase significantly the number of flies alighting on the target in either species. however, after contact with the sebum coated target, both species showed an increase in flight activity, and g. m.morsitans showed a greater tendency to return to the target. this behaviour resulted in a num ...19892519690
the probability of tsetse acquiring trypanosome infection from single blood meal in different localities in kenya.the probability of tsetse, glossina pallidipes, acquiring a trypanosome infection from a single blood meal was estimated in five localities on the kenya coast which were selected for differences in habitat and host availability. the probability that one blood meal contained infective trypanosoma congolense was 0.0077 in rural areas with domestic animals, 0.0019 in extensive areas of natural habitat with wild hosts and 0.0013 in an area with domestic animals under regular chemoprophylaxis. the re ...19852865875
the feeding habits of the tsetse, glossina pallidipes austen on the south kenya coast, in the context of its host range and trypanosome infection rates in other parts of east africa.the results of blood-meal identifications for 651 glossina pallidipes from 5 subpopulations near the kenya coast south of mombasa, and one, 70 km inland, are presented. bushpigs and/or warthogs were important hosts for g. pallidipes at all sites. other major hosts included elephant, buffalo and bushbuck where they were present, and on a dairy ranch nearly 30% of feeds were taken from cattle. there was a general relationship between the numbers and diversity of wild herbivores and the abundance o ...19882907261
some concepts of the interaction of trypanosoma (nannomonas) congolense and glossina pallidipes.light and electron microscope investigations were carried out on the infection with trypanosoma (nannomonas) congolense of laboratory-reared tsetse flies glossina pallidipes. trypanosomes became entombed in the peritrophic membrane (pm) to form intraperitrophic cavities which were more electron-translucent than the amorphous layer of the pm. a hypothesis is suggested that after migration anteriorly in the ectoperitrophic space, the trypanosomes become enmeshed in the pm during its formation in t ...19883250337
the investigation of trypanosoma brucei isolates obtained from glossina pallidipes in south nyanza, kenya.during studies to determine the main trypanosoma brucei rhodesiense transmission sites in lambwe valley, western kenya, glossina pallidipes were collected from two areas in the valley and examined for trypanosome infection. t. brucei isolated from infected flies were tested for their response to the lethal effects of human blood (blood incubation infectivity test, biit) and also characterized using isoenzyme electrophoresis. six of the 26 t. brucei tested were biit positive, two of which had enz ...19873669129
tsetse and trypanosomiasis in the lambwe valley, kenya.the lambwe valley is shared between wild animals in a national park and adjacent human settlements with domestic livestock. thicket and woodland in the valley are heavily infested with glossina pallidipes. rhodesian sleeping sickness continues to be a major human health hazard and livestock losses from nagana seriously affect the local economy. epidemiology is characterized by periods of quiescence and flare-up, reflecting intermittent vector control measures to reduce transmission. the situatio ...19863810794
properties of a novel dna virus from the tsetse fly, glossina pallidipes.virus particles were isolated from hypertrophied salivary glands of the tsetse fly, glossina pallidipes collected near mombasa, kenya. purified virus particles were rod-shaped, 57 nm wide by 700 to 1300 nm long. particle lengths fell into two size classes, with 'short' particles averaging 869 nm and 'long' particles 1175 nm. the virus particles morphologically resembled elongated baculovirus nucleocapsids although, unlike baculoviruses, no fully enveloped virions were found in purified preparati ...19863950581
observations on age-grouping the tsetse fly, glossina pallidipes, by wing-fray and ovarian dissection, on the south kenya coast.female glossina pallidipes from biconical trap collections at five localities on the south kenya coast were age-grouped by wing-fray and ovarian condition, and their trypanosome infection rates determined. from simultaneous application of the two age-grouping methods to 991 female tsetse, 17 reproductive age-categories were recognized. separation into these categories was supported by a highly significant correlation between estimated age and proportion of tsetse uninfected by trypanosomes. limi ...19854073997
characterization of potentially man-infective trypanosoma brucei from an endemic area of sleeping sickness in kenya.human trypanosomiasis caused by trypanosoma brucei rhodesiense has affected the human population in lambwe valley, western kenya, for more than 20 years. a characteristic feature of the disease has been the repeated recrudescense at restricted residual foci. studies carried out on the incidence of trypanosome infection rates in the vector glossina pallidipes during the last two years have shown high incidence of pathogenic african trypanosomes in the area. an overall trypanosome infection rate o ...19854081544
the nature of the establishment barrier for trypanosoma brucei in the gut of glossina pallidipes. 19734360226
factors contributing to the stability of a glossina pallidipes aust. population in the lossitete forest. 19744471453
the role of game animals in the maintenance of endemic and enzootic trypanosomiases in the lambwe valley, south nyanza district, kenya.rhodesian sleeping sickness and bovine trypanosomiasis were endemic in the lambwe valley of western kenya, where the vector of both diseases was a tsetse fly glossina pallidipes. since a large resident population of game animals also inhabited the valley, a programme was designed to assess the relationships between game animals, tsetse, and trypanosome populations and the results were collated with some aspects of local human ecology and the general epidemiological situation in the valley. of 13 ...19724544824
the hosts and trypanosome infection rates of glossina pallidipes in the lambwe and roo valleys.several thousand glossina pallidipes flies were dissected to determine trypanosome infection rates in the lambwe valley and to collect information on the hosts of this tsetse. a total of 1 450 (19.3%) flies had mature trypanosome infections but the rate varied between 9.6% and 30.9% in the lambwe valley. in the roo valley the rate was 19.7-28.6%. blood-meal squashes from tsetse collected in the roo valley and obaluanda areas and in the ruma, otuok, and rari thickets showed that the important hos ...19724544830
observations on the relative attractiveness to glossina pallidipes of different animal baits, a tsetse trap, and a fly-round patrol.studies conducted in the lambwe valley, kenya, have shown that in the absence of wild hosts, glossina pallidipes was more attracted to a calf than to a sheep, a goat, a man, or a tsetse trap, although the latter attracted more flies than the nonbovid baits. other investigations have shown that a newly developed tsetse trap was much more efficient at catching g. pallidipes than a standard fly-round patrol technique. an added advantage of the trap was that the sex ratio of flies caught by it was m ...19724544831
the influence of game animals on the distribution and feeding habits of glossina pallidipes in the lambwe valley.the role of game animals as important hosts of some species of tsetse, including glossina pallidipes, has been studied in detail in the lambwe valley area of kenya. a large population of g. pallidipes existed in association with a varied community of game animals in the study area, and the investigation was designed to determine which of the hosts available to g. pallidipes were actively selected and whether the preferred hosts influenced the distribution of the tsetse population. bushbuck (trag ...19724544832
the maintenance of a colony of glossina pallidipes austen. 19725038251
the establishment and initial survival of trypanosoma brucei in the gut of glossina pallidipes. 19725048843
the regulation of ovulation in the tsetse-fly, glossina pallidipes austen. 19715130027
effect of the developmental state of the host guinea-pig on the feeding activity of the tsetse fly glossina pallidipes aust. 19695375526
growth, longevity, and the frequency of feeding of glossina pallidipes austen. 19685693985
effect of gamma-radiation on glossina pallidipes aust. 19695809261
seasonal and diurnal variations in physiological age and trypanosome infection rate of females of glossina pallidipes aust., g. palpalis fuscipes newst. and g. brevipalpis newst. 19665915071
trypanosoma (nannomonas) congolense in the basement lamina of the anterior midgut cells of glossina pallidipes. 19806104430
comparative studies on fat reserves, feeding and metabolic strategies of flies from two allopatric populations of glossina pallidipes austen in kenya. 19826126098
a quantification of the risk of trypanosomiasis infection to cattle on the south kenya coast.the number of trypanosome-infected bites received by cattle grazed around an 8 ha area of forest harbouring a semi-isolated population of glossina pallidipes austen was estimated. the absolute size of the tsetse population was determined by mark-release-recapture techniques, the tsetse host range by the identification of blood-meals, and trypanosome infection rates by dissection of samples of tsetse. feeding frequency was estimated and the number of cattle present was known. it was estimated tha ...19836142631
first record of a reptile trypanosome isolated from glossina pallidipes in kenya.trypanosomes, isolated from the gut of a naturally infected glossina pallidipes in kiboko, kenya, were grown in vitro. the cultured trypanosomes ("f4"-stock) showed a wide variety in morphological stages, not characteristic of the salivarian trypanosomes that are known to occur in the kiboko area. identification of the "f4"-stock was attempted by isoenzyme studies, infection of tsetse flies and of experimental animals. electrophoretic isoenzyme patterns of the "f4"-organisms were developed for t ...19836837099
sex recognition pheromone in the tsetse fly glossina pallidipes austen.sexual responses of adult male g. pallidipes towards baited decoys show that a contact sex pheromone for this species is present in the hydrocarbon fraction of the adult female cuticle. results are consistent with the view that the pheromone is a c35 compound and is present in sufficient quantity in newly emerged females to elicit maximum responses from males. thus, maturation of sexual responsiveness is considered to be behavioral in females of this species.19827084410
a comparison of susceptibility to stocks of trypanosoma simiae of glossina pallidipes originating from allopatric populations in kenya.a colony of glossina pallidipes which originated from nguruman, rift valley province, kenya, was significantly more susceptible than a colony of the same species which originated from shimba hills, coast province, kenya, to infection with a stock of trypanosoma simiae cp 11 isolated from wild g. austeni in coast province, kenya, irrespective of whether pigs or goats were used as infecting hosts. male g.pallidipes from both the colonies were more susceptible than females to this t.simiae stock. s ...19957548937
blood meal sources of glossina pallidipes and g. longipennis (diptera: glossinidae) in nguruman, southwest kenya.in total, 1,952 glossina pallidipes austen and 1,098 g. longipennis corti adults were collected in forest and savanna habitat in nguruman, southwestern kenya, by ng2g traps during the dry season of 1992. of these, 339 individuals (11.1%) had blood meals, of which 155 (45.7%) were identified by direct enzyme-linked immunosorbent assay. the most frequent blood meal source was bushbuck, followed by ostrich, elephant, buffalo, and warthog. few meals were taken from cattle. the findings of frequent b ...19957616534
trypanosome infections of the tsetse fly glossina pallidipes in the luangwa valley, zambia.trypanosome infections of glossina pallidipes were investigated at a site in the luangwa valley, zambia between june 1991 and september 1992. almost 3700 flies were captured, dissected, screened for trypanosome infection, and aged using both wing fray and (for females) ovarian categories. dna probes were used to identify midgut infections. prevalences of mature infections were 6.2% trypanosoma vivax-type and 3.1% t. congolense-type (including low prevalances of t. brucei, t. simiae and another n ...19947772128
a comparison of susceptibility to stocks of trypanosoma vivax of glossina pallidipes from allopatric populations in kenya. 19957787230
a comparison of three types of "m" traps for sampling tsetse fly (diptera: glossinidae) populations at south luangwa game management area, zambia.a field trial was conducted between 27th july and 1st august, 1992 in mfuwe, south luangwa, zambia to assess the effectiveness of locally developed "m" traps for suppressing and sampling the tsetse flies glossina pallidipes austen and glossina morsitans morsitans westwood. the tsetse catches in the "m" traps and the standard f3 traps were collected at 24 hour intervals. the highest catches of both tsetse species in the series of "m" traps were in the m3 trap. the numbers of female flies caught f ...19947812999
control of tsetse flies in uganda by dipping cattle in deltamethrin.the effect of treating cattle with deltamethrin to control tsetse flies and ticks was investigated on 2 ranches 8 km apart in central uganda where there is a high risk of trypanosomosis. this area had a moderate challenge of glossina pallidipes. the cattle had very low challenge of rhipicephalus appendiculatus, amblyomma variegatum, boophilus decolaratus and rhipicephalus evertsi evertsi, due to regular treatment with dioxathion. on one ranch a dip was charged with deltamethrin to treat cattle r ...19948009646
genetics of two colonies of glossina pallidipes originating from allopatric populations in kenya.two large colonies, originating from allopatric populations of glossina pallidipes austen, in the shimba hills and nguruman, kenya, which differ biologically and with respect to vectorial competence, were compared at fourteen enzyme loci using polyacrylamide gel electrophoresis. the colonies had similar levels of genetic diversity with approximately half of the loci being polymorphic, an average of 1.6-1.7 alleles per locus, and a mean heterozygosity per locus of approximately 18.4%. however, th ...19948025320
midgut lectin activity and sugar specificity in teneral and fed tsetse.midgut infection rates of trypanosoma congolense in glossina palpalis palpalis and of trypanosoma brucei rhodesiense in glossina pallidipes are potentiated by the addition of d+ glucosamine to the infective feed, but not to the levels of super-infection reported for g.m.morsitans, g.p.palpalis and g.pallidipes are shown to possess two trypanocidal molecules: a glucosyl lectin which can be inhibited by d+ glucosamine and a galactosyl molecule inhibited by d+ galactose. addition of both d+ glucosa ...19948161852
the nutritional state of male tsetse flies, glossina pallidipes, at the time of feeding.the feeding intervals of tsetse flies have been estimated from the nutritional state of flies caught in traps. however, such estimates have been disputed on the grounds that traps catch a biased, hungry sample of the flies which are seeking hosts and will feed. in this paper we present data on the nutritional state of tsetse flies caught approaching and feeding on oxen. individual oxen were surrounded with an incomplete ring of electric nets which caught glossina pallidipes austen that were appr ...19938268484
a comparison of susceptibility of two allopatric populations of glossina pallidipes for stocks of trypanosoma congolense.a colony of glossina pallidipes austen which originated from nguruman, rift valley province, kenya, was significantly more susceptible to infection (19.3%) with a stock of trypanosoma congolense broden isolated from g. pallidipes in nguruman than a colony of the same species which originated from shimba hills, coast province, kenya (5.6%). male g.pallidipes from nguruman were significantly more susceptible than females to this t.congolense stock whilst the susceptibility of both sexes of g.palli ...19938268493
the influence of host blood on infection rates in glossina morsitans sspp. infected with trypanosoma congolense, t. brucei and t. simiae.trypanosoma congolense, t. brucei and t. simiae isolated from wild-caught glossina pallidipes were fed to laboratory-reared g. morsitans centralis and g.m. morsitans to determine the effect of host blood at the time of the infective feed on infection rates. bloodstream forms of trypanosomes were membrane-fed to flies either neat, or mixed with blood from cows, goats, pigs, buffalo, eland, waterbuck and oryx. the use of different bloods for the infective feed resulted in differences in infection ...19938355996
effect of host packed cell volume on the bloodmeal size of male tsetse flies, glossina pallidipes.haematin contents of engorged, male tsetse flies, glossina pallidipes austen, were compared with the packed cell volumes of oxen on which they had fed. haematin contents increased with packed cell volume up to packed cell volumes of approximately 30%. haematin contents appeared to level off or decline with further increase in packed cell volume. these results support a model of blood-feeding in tsetse flies in which the rate of blood consumption decreases as packed cell volume increases, because ...19958541591
a comparison of the susceptibility to stocks of trypanosoma brucei brucei of glossina pallidipes originating from allopatric populations in kenya. 19958541599
ultrastructural changes in the milk gland of tsetse glossina morsitans centralis (diptera; glissinidae) female infected by a dna virusmilk glands, dissected out and collected from glossina morsitans centralis (machado) females, artificially inoculated at the third-instar larval stage with a virus suspension obtained from hypertrophied salivary glands of wild-caught virus-infected glossina pallidipes (austen), were processed for routine electron microscopy and examined for pathological changes. they were compared to milk glands dissected out from normal female g.m. centralis at the same stage of pregnancy cycle. upon dissection ...19968954813
the daily feeding rate of tsetse (diptera: glossinidae) on cattle at galana ranch, kenya and comparison with trypanosomiasis incidence.at galana ranch, south-eastern kenya, for 2 days each month from january to may 1993. glossina pallidipes and g. longipennis were sampled around a heifer for 30 min every hour from 06:00 to 19:00. there was a seasonal decline in tsetse abundance; estimates of the total number attracted to the heifer in 1 day ranged from 556 g. pallidipes in january to 0 in may and 122 g. longipennis in february to 27 in may. the number of tsetse estimated to have fed on the heifer in 1 day during peak months was ...19979164602
host preferences of tsetse (diptera: glossinidae) based on bloodmeal identifications.an enzyme-linked immunosorbent assay (elisa) was developed to identify the origin of vertebrate blood in the guts of 29 245 wild-caught flies of eleven glossina species from various ecological zones of africa. depending on the quality of the bloodmeal samples, 62.8% of the samples were identified and could be assigned to a host-group (e.g. ruminant), family (e.g. bovidae) or species (e.g. bos spp.). a total of 13 145 samples (44.9%) was identifiable up to the species level. with a few exceptions ...19989622371
factors affecting the landing and feeding responses of the tsetse fly glossina pallidipes to a stationary ox.in zimbabwe, studies were made of the landing and feeding responses of glossina pallidipes on an ox. of the tsetse approaching an ox, approximately 70% fed. increasing densities of tsetse increased the grooming responses of the ox but had no significant effect on the percentage of tsetse that engorged. the landing site of tsetse on the ox varied with density, with approximately 50% landing on the legs at low densities (< 20 flies per ox), compared to approximately 80% at densities > 40 flies per ...19989622375
factors influencing the prevalence of trypanosome infection of glossina pallidipes on the ruvu flood plain of eastern tanzania.we report the pattern of infection of glossina pallidipes with trypanosoma vivax and t. congolense at a site in the coast region of eastern tanzania, studied between november 1993 and december 1994. of the 2315 flies dissected 114 (4.9%) were t. congolense positive, 77 (3.3%) were t. vivax positive and 2 (0.1%) were t. brucei positive. fly age was determined by the pteridine fluorescence method. prevalence of infection was most strongly affected by month and the linear effect of age with the int ...19989698260
breeding structure of glossina pallidipes populations evaluated by mitochondrial variation.mitochondrial dna diversity was studied at four loci in six natural populations of the tsetse fly glossina pallidipes from zimbabwe, mozambique, kenya, and ethiopia. single-locus diversity varied from 0.39 at 12s to 0.65 at coii. a total of 32 haplotypes was found with a mean of 6.4 +/- 2.9 per locus. to study breeding structure, diversity at two loci, coii and 16s2, was evaluated in 18 populations sampled from an area of approximately 1,611,000 km2 and in three laboratory cultures. twenty-six h ...199910589514
feeding behaviour of glossina pallidipes and g. morsitans centralis on boran cattle infected with trypanosoma congolense or t. vivax under laboratory conditions.in field studies, tsetse flies (diptera: glossinidae) feed more successfully on cattle infected with trypanosoma congolense broden (kinetoplastida: trypanosomatidae) than on cattle infected with t. vivax ziemann or uninfected cattle. here we describe the first laboratory investigation of this phenomenon. in the first experiment, caged glossina pallidipes austen were fed for 1 and 5 min on a boran steer infected with t. congolense clone il 1180 and on an uninfected steer. feeding success was reco ...200011016437
a history of rhodesian sleeping sickness in the lambwe valley.the main events in the spread of rhodesian sleeping sickness around the eastern shores of lake victoria during the 1930s and 1940s are summarized and the history of the disease in the lambwe valley area of western kenya is described since its appearance there in 1959. the area was very receptive to the introduction and dispersal of t. rhodesiense on account of a close association between human communities and their domestic livestock, a large tsetse (glossina pallidipes) population, and game ani ...19724544821
problems of field testing theoretical models: a case study.the problems of field-testing models are discussed with reference to a population simulation model for the tsetse fly glossina pallidipes austen developed by us at nguruman in southwestern kenya. model predictions showed a reasonable fit to the changes in the biconical trap index of population size, but tended to overestimate some changes and underestimate others. a more rigorous test for the model is to manipulate one of the population parameters and compare model predictions with the observed ...19892802817
size and mortality rates of glossina pallidipes in the semi-arid zone of southwestern kenya.seasonal changes in the mean size of tsetse, glossina pallidipes austen, as indicated by wing vein length, were monitored during 1983-86 at nguruman, southwestern kenya. changes in size of nulliparous females and wing fray category 1 males were shown to be correlated with the relative humidity 2 months before they were captured. soil temperature when flies were in the pupal stage had much less effect. size dependent mortality was demonstrated, with the mean size of flies emerging from pupae sign ...19892519651
spatial and temporal distribution of tsetse fly trap catches at nguruman, southwest kenya.spatial and temporal dynamics of rapidly growing populations of tsetse flies at nguruman, southwest kenya during 1993-1995, were investigated, following six years of intensive population suppression with traps over a c. 100 km2 area. the two tsetse species present were randomly distributed in the short rainy season, but were aggregated in the dry and long rainy seasons. maximum temperature was the dominant weather factor associated with the degree of aggregation. trends in catches at 20 fixed si ...200111415476
rate of trypanosome killing by lectins in midguts of different species and strains of glossina.the activity of lectins in different species of tsetse was compared in vivo by the time taken to remove all trypanosomes from the midgut following an infective feed and in vitro by agglutination tests. teneral male glossina pallidipes austen, g. austeni newstead and g. p. palpalis r-d. removed 50% of all trypanosoma brucei rhodesiense stephens & fantham infections within 60 h. a 'refractory' line of g. m. morsitans westwood took 170 h to kill 50% infections while a 'susceptible' line of the same ...19892519650
trap efficiency for glossina pallidipes (diptera: glossinidae) at nguruman, south-west kenya.an incomplete ring of electric nets was evaluated as a means of estimating trap efficiency for glossina spp. this methodology assumes flies approach the trap directly, and then enter, or leave directly in random directions. these results showed that the ratio of the number of flies intercepted on the outside of the electric nets to the number on the inside was lower than predicted by this single-approach behavioural model. moreover, an incomplete ring of nets around a trap reduced trap catch mor ...200111818038
population structure of the tsetse fly glossina pallidipes estimated by allozyme, microsatellite and mitochondrial gene diversities.diversities at nuclear and mitochondrial loci were examined in eleven natural populations of glossina pallidipes from east and southern africa. alleles in each class of loci are assumed to be selectively neutral. allozyme gene diversities (heterozygosities) averaged over eight loci were 0.146 among seven kenya populations and 0.201 among four southern african populations. microsatellite diversity averaged over three loci was 0.250 in kenya and only 0.218 in southern africa. mitochondrial diversi ...200211841501
monitoring tsetse fly populations. ii. the effect of climate on trap catches of glossina pallidipes.in part i it was shown that the sampling distribution of trap catches of tsetse flies, glossina pallidipes austen, at nguruman, kenya, using unbaited biconical traps follows a poisson distribution. in this paper we examine the effect of humidity and temperature on day-to-day and seasonal variations in the trap catches. it is shown that the seasonal variation is significantly correlated with maximum daily temperature, the catches increasing with temperature when the maximum temperature is below 3 ...19902132982
monitoring tsetse fly populations. i. the intrinsic variability of trap catches of glossina pallidipes at nguruman, kenya.during 1986 the tsetse fly glossina pallidipes austen was monitored daily at nguruman, southwestern kenya, using three unbaited biconical traps. this was done to investigate the nature and causes of daily variation in trap catches. the variability of the observed catches was compared to a model which includes the trapping probability and the stochastic variation in the sex-ratio. by comparing the catches of male and female flies we are able to establish the sampling distribution of the trap catc ...19902132981
studies on trap effectiveness of tsetse flies (glossina spp. (diptera: glossinidae)) in the tanga region of north eastern tanzania.at mkwaja and mivumoni ranches in ne tanzania the catches of glossina pallidipes austen, g. brevipalpis newstead, g. morsitans morsitans westwood and g. austeni newstead were usually about two to three times greater in traps of the ngu, epsilon and f3 types than in the blue biconical and pyramidal traps when used with odours. catches from moving men were improved about three times when the men carried a black screen, and increased by about another seven times for female g. pallidipes when a vehi ...200312875933
interactions between cattle and biting flies: effects on the feeding rate of tsetse.in zimbabwe, studies were made of the effect of host behaviour on the feeding success of glossina pallidipes austen and g. morsitans morsitans westwood (diptera: glossinidae) attracted to cattle of different age and sex. the mean feeding rates for male and female g. pallidipes attracted to oxen were 60% and 58%, respectively, compared to 33% and 53% for male and female g. m. morsitans. the feeding rate of g. pallidipes varied between oxen and was inversely correlated with a host's rate of defens ...200011129704
detection of trypanosoma brucei rhodesiense in animals from sleeping sickness foci in east africa using the serum resistance associated (sra) gene.the human serum resistance associated (sra) gene has been found exclusively in trypanosoma brucei rhodesiense, allowing the unequivocal detection of this pathogen in reservoir hosts and the tsetse vector without recourse to laborious strain characterisation procedures. we investigated the presence of the sra gene in 264 t. brucei ssp. isolates from humans, domestic animals and glossina pallidipes from foci of human trypanosomiasis in kenya and uganda. the sra gene was present in all isolates tha ...200415099811
metabolic rate variation in glossina pallidipes (diptera: glossinidae): gender, ageing and repeatability.despite the importance of metabolic rate in determining flight time of tsetse and in mediating the influence of abiotic variables on life history parameters (and hence abundance and distribution), metabolic rate measurements and their repeatability have not been widely assessed in these flies. we investigate age-related changes in standard metabolic rate (smr) and its repeatability, using flow-through respirometry, for a variety of feeding, gender and pregnancy classes during early adult develop ...200415121455
grouping of trypanosome species in mixed infections in glossina pallidipes.trypanosomes in the dissection-positive proboscis of glossina pallidipes were identified by pcr using species-specific primers. of the 3741 flies dissected 643 were proboscis positive. pcr was performed on 406 dissection-positive probosces giving positive identifications in 352 (86.7%) and infection rates of 14.8% for congolense-type infections, 2.8% for vivax-type infections and 1.4% for the unidentified group. of the 352 pcr identified infections 225 were single, 111 were double, 13 were tripl ...200010874721
immunization of rabbits with glossina pallidipes tsetse fly midgut proteins: effects on the fly and trypanosome transmission.proteins isolated from the midgut of glossina pallidipes were used to immunize rabbits and their efficacy as vaccine candidate(s) against the fly, and their potential to block transmission of trypanosoma brucei rhodesiense assessed. two fractions, detergent (det) and aqueous (aq) fractions were separated using a non-ionic detergent (triton x-114) and a series of bioassay experiments carried out using serum obtained from rabbits immunized with either of the two fractions. the mortality rates of t ...200515893620
artificial larviposition sites for field collections of the puparia of tsetse flies glossina pallidipes and g. m. morsitans (diptera: glossinidae).tsetse flies glossina pallidipes austen and g. morsitans morsitans westwood deposit their larvae in warthog burrows, in august-november, at rekomitjie research station, zambezi valley, zimbabwe. artificial burrows, made from 200-l steel drums, were used to sample these flies and to collect their puparia. sand-filled plastic trays in the burrows served as a substrate for larval deposition. the sand was covered with c. 2 cm of leaf litter after it was shown that only 3% of larvae were deposited on ...200515960876
evaluation of conventional odour attractants for glossina brevipalpis and glossina austeni (diptera: glossinidae) in south africa.the components of the synthetic ox-odour used in zimbabwe against glossina pallidipes and g. m. morsitans were evaluated for the attraction of g. brevipalpis and g. austeni in south africa. the zim babwe mixture (zim-mix), which consisted or acetone and a 1:4:8 mixture of 3-n-propyl phenol, 4-methyl phenol and 1-octen-3-ol, increased the catches of g. brevipalpis by c. 2.1-4.4 times compared to when no odours were used. one of the odour components, namely 3-n-propyl phenol, did not significantly ...199910689703
development of an adaptive tsetse population management scheme for the luke community, ethiopia.since 1996, tsetse (glossina spp.) control operations, using odor-baited traps, have been carried out in the luke area of gurage zone, southwestern ethiopia. glossina morsitans submorsitans newstead was identified as the dominant species in the area, but the presence of glossina fuscipes newstead and glossina pallidipes austen also was recorded. here, we refer to the combined number of these three species and report the work undertaken from october 2002 to october 2004 to render the control syst ...200516465742
the relative contributions of developmental plasticity and adult acclimation to physiological variation in the tsetse fly, glossina pallidipes (diptera, glossinidae).recent reviews of the adaptive hypotheses for animal responses to acclimation have highlighted the importance of distinguishing between developmental and adult (non-developmental) phenotypic plasticity. there has been little work, however, on separating the effects of developmental plasticity from adult acclimation on physiological traits. therefore, we investigated the relative contributions of these two distinct forms of plasticity to the environmental physiology of adult tsetse flies by expos ...200616513933
use of insecticide-impregnated targets for the control of tsetse flies (glossina spp.) and trypanosomiasis occurring in cattle in an area of south-west ethiopia with a high prevalence of drug-resistant trypanosomes.in the ghibe valley, south-west ethiopia, a tsetse control trial using deltamethrin-impregnated targets was started in may 1990. the mean relative density of the main vector, glossina pallidipes, fell from 2.1 flies per trap per day in the 12 months prior to introduction of tsetse control to 0.41 flies per trap per day in the 12 months after tsetse control was initiated. the annual mean prevalence of trypanosoma congolense infections in cattle fell from 32% in the 2 years before tsetse control t ...19968911444
the effect of cattle infection by trypanosoma congolense on the attraction, and feeding success, of the tsetse fly glossina pallidipes.an incomplete ring of electric nets was placed around uninfected cattle and cattle infected with trypanosoma congolense. the numbers of fed and unfed glossina pallidipes caught on the nets were used to estimate the attractiveness of infected and uninfected cattle to tsetse, and the feeding success of tsetse on the cattle. there was no difference in the attractiveness of infected and uninfected cattle to g. pallidipes. however, the feeding success of g. pallidipes on infected cattle was 75% great ...19938316432
characterization of microsatellite markers in the tsetse fly, glossina pallidipes (diptera: glossinidae).glossina pallidipes is a vector of african trypanosomiasis. here we characterize eight new polymorphic microsatellite loci in 288 g. pallidipes sampled from 12 kenya populations. the number of alleles per locus ranged from four to 36 with a mean of 20.5 +/- 10.1. expected single locus heterozygosities varied from 0.044 to 0.829. heterozygosity averaged 0.616 +/- 0.246. no linkage disequilibrium was found. we also report results in eight other tsetse species estimated by using the primers develop ...200316718306
feeding behaviour of tsetse flies (glossina pallidipes austen) on trypanosoma-infected oxen in kenya.an incomplete ring of electric nets was placed around oxen which were either uninfected, infected with trypanosoma vivax, or infected with t. congolense. the numbers of fed and unfed glossina pallidipes caught on the nets were used to estimate the attractiveness of the oxen to tsetse, and the feeding success of the tsetse on the oxen. oxen infected with t. congolense attracted more g. pallidipes than the other groups of oxen. taking into consideration daily variation in the abundance or activity ...19957724237
studies on glossina pallidipes, g. fuscipes fuscipes and g. brevipalpis in terms of the epidemiology and epizootiology of trypanosomiases in south-eastern uganda.glossina pallidipes, g. f. fuscipes and g. brevipalpis in stages i and ii of hunger were caught from bukunya and buyundo villages in south-east uganda during the period december 1969 to february 1971, and the origins of their blood meals identified. g. pallidipes fed mainly on bovids in the two villages; bushbuck was the most favoured host (44.9% of all blood feeds) though in buyundo buffalo provided a significant alternative (20.8%). g. f. fuscipes frequently fed on bovids (75.6%), particularly ...19807436606
vector--parasite relationships: the effect of trypanosoma (nannomonas) congolense on glossina pallidipes.an electron microscope study was made on the infection by trypanosoma (nannomonas) congolense of the tsetse fly glossina pallidipes. infected flies showed many clear abnormalities in their gut cells and peritrophic membrane. these features are described and illustrated.19836625732
tsetse and other biting fly responses to nzi traps baited with octenol, phenols and acetone.octenol (1-octen-3-ol), acetone, 4-methylphenol, 3-n-propylphenol, and other potential attractants (human urine, stable fly faeces), as well as guiacol, creosol (potential repellents), were tested as baits for biting flies in north america using standard phthalogen blue if3gm cotton nzi traps, or similar commercial polyester traps. baits were tested during the summers of 2001-04 at a residence in canada and during january-august 2001 at a dairy in the u.s.a. behaviour in the presence of octenol ...200717373949
macrogeographic population structure of the tsetse fly, glossina pallidipes (diptera: glossinidae).tsetse flies are confined to sub-saharan africa where they occupy discontinuous habitats. in anticipation of area-wide control programmes, estimates of gene flow among tsetse populations are necessary. genetic diversities were partitioned at eight microsatellite loci and five mitochondrial loci in 21 glossina pallidipes austin populations. at microsatellite loci, nei's unbiased gene diversity averaged over loci was 0.659 and the total number of alleles was 214, only four of which were shared amo ...200516197564
refractoriness in tsetse flies (diptera: glossinidae) may be a matter of timing.tsetse flies (diptera: glossinidae: glossina spp.) are vectors for african trypanosomiasis, a devastating disease that kills both people and animals in sub-saharan africa. trypanosomes ingested with an infected bloodmeal reside within the gut of tsetse and eventually move to the salivary glands where they become transmissible during blood feeding. although tsetses are efficient vectors for disease transmission, infection prevalence in the field is surprisingly low, a trait referred to as refract ...200717695022
on the interpretation of age-prevalence curves for trypanosome infections of tsetse flies.epidemiological models are used to analyse 8 published data sets reporting age-prevalence curves for trypanosome infections of the tsetse fly glossina pallidipes. a model assuming a fixed maturation period and a rate of infection which is independent of fly age is adequate for trypanosoma vivax-type infections, explaining 98% of observed variance in prevalence by site and age, allowing that the rate of infection may be site dependent. this model is not adequate for t. congolense-type infections ...19989509024
distribution and abundance of trypanosome (subgenus nannomonas) infections of the tsetse fly glossina pallidipes in southern africa.over 10 000 glossina pallidipes tsetse flies were collected during two field studies in the zambezi valley, zimbabwe and one in the luangwa valley, zambia. these were screened for mature trypanosome infections and 234 dot-blot preparations were made of infected midguts, which were screened using dna probes or pcr with primers specific to different species or types of the trypanosome subgenus nannomonas. over 70% of midgut infections were successfully identified as either trypanosoma godfreyi, t. ...19969147687
epidemiology of trypanosome infections of the tsetse fly glossina pallidipes in the zambezi valley.the epidemiology of trypanosome infections of glossina pallidipes was studied at a riverine site in the zambezi valley, zimbabwe for a period of 13 months. over 9000 flies were captured using a single trap. these flies were dissected, screened for trypanosome infection, sexed, and aged using both wing fray and (for females) ovarian category indices. midgut infections were identified to species using recently developed dna probes. the overall prevalence of mature infections was 5.5%, comprising 3 ...19938341584
glossina pallidipes and open country in the coastal area of kenya. 194918130376
genetic transformation and phylogeny of bacterial symbionts from tsetse.two isolates of bacterial endosymbionts, gp01 and gm02, were established in cell free medium from haemolymph of the tsetse, glossina pallidipes and g. morsitans. these microorganisms appear similar to rickettsia-like organisms reported previously from various tsetse species. the 16s rrna sequence analysis, however, placed them within the gamma subdivision of the proteobacteria, phylogenetically distinct from most members of the rickettsiaceae which align with the alpha subdivision. distinct mult ...19938269090
detection of trypanosoma brucei in field-captured tsetse flies and identification of host species fed on by the infected flies.the prevalence of trypanosome infections in tsetse flies in the chiawa area of lower zambezi in zambia, with endemic trypanosomosis, was determined by a polymerase chain reaction (pcr) method that allowed the detection of trypanosome dna and determination of the type of animal host fed on by the tsetse fly glossina pallidipes, using tsetse-derived dna extracts as templates. ninety g. pallidipes (82 females and 8 males; 18.3%) of the 492 flies captured by baited biconical traps tested positive fo ...200818399780
simple tools for assembling and searching high-density picolitre pyrophosphate sequence data.abstract:200818423012
epidemiology of bovine trypanosomiasis in the ghibe valley, southwest ethiopia. 1. tsetse challenge and its relationship to trypanosome prevalence in cattle.in this, the first of a series of papers on the epidemiology of bovine trypanosomiasis in the ghibe valley, southwest ethiopia, the tsetse populations and their relationships to the prevalence of trypanosome infections in cattle are described. the tsetse challenge to cattle at two sites sites in the area was estimated as the product of tsetse relative density and the trypanosome infection rate in flies. the proportion of feeds taken by tsetse from cattle was also considered. three tsetse species ...19938098898
prevalence and source of trypanosome infections in field-captured vector flies (glossina pallidipes) in southeastern zambia.the prevalence of trypanosome infections in tsetse flies, glossina pallidipes, collected from chiawa and chakwenga in zambia with endemic trypanosomosis was assessed by polymerase chain reaction (pcr). out of the 550 g. pallidipes, 58 (10.5%) flies were found to harbor trypanosome dna. infection rates of tsetse with trypanosoma vivax universal, trypanosoma congolense savannah, t. congolense forest and t. congolense kilifi were 4.2% (23/550), 4.7% (26/550), 1.1% (6/550) and 1.6% (9/550), respecti ...200818840966
trypanosoma brucei rhodesiense transmitted by a single tsetse fly bite in vervet monkeys as a model of human african trypanosomiasis.we have investigated the pathogenicity of tsetse (glossina pallidipes)-transmitted cloned strains of trypanosoma brucei rhodesiense in vervet monkeys. tsetse flies were confirmed to have mature trypanosome infections by xenodiagnosis, after which nine monkeys were infected via the bite of a single infected fly. chancres developed in five of the nine (55.6%) monkeys within 4 to 8 days post infection (dpi). all nine individuals were successfully infected, with a median pre-patent period of 4 (rang ...200818846231
quantitative pcr analysis of the salivary gland hypertrophy virus (gpsghv) in a laboratory colony of glossina pallidipes.many species of tsetse flies can be infected by a virus that causes salivary gland hypertrophy (sgh) and virus isolated from glossina pallidipes (gpsghv) has recently been sequenced. flies having sgh have a reduced fecundity and fertility. to better understand the impact of this virus in a laboratory colony of g. pallidipes, where the majority of flies are infected but asymptomatic, and to follow the development of sgh in symptomatic flies in relation to virus copy number, a quantitative pcr (qp ...200919014982
two viruses that cause salivary gland hypertrophy in glossina pallidipes and musca domestica are related and form a distinct phylogenetic clade.glossina pallidipes and musca domestica salivary gland hypertrophy viruses (gpsghv and mdsghv) replicate in the nucleus of salivary gland cells causing distinct tissue hypertrophy and reduction of host fertility. they share general characteristics with the non-occluded insect nudiviruses, such as being insect-pathogenic, having enveloped, rod-shaped virions, and large circular double-stranded dna genomes. mdsghv measures 65x550 nm and contains a 124 279 bp genome (approximately 44 mol% g+c conte ...200919141442
hytrosaviridae: a proposal for classification and nomenclature of a new insect virus family.salivary gland hypertrophy viruses (sghvs) have been identified from different dipteran species, such as the tsetse fly glossina pallidipes (gpsghv), the housefly musca domestica (mdsghv) and the narcissus bulbfly merodon equestris (mesghv). these viruses share the following characteristics: (i) they produce non-occluded, enveloped, rod-shaped virions that measure 500-1,000 nm in length and 50-100 nm in diameter; (ii) they possess a large circular double-stranded dna (dsdna) genome ranging in si ...200919458899
characterization of trypanozoon stocks from the south nyanza sleeping sickness focus in western kenya.220 trypanosoma (trypanozoon) brucei sp. stocks isolated between 1969 and 1983 from the lambwe valley sleeping sickness focus in south nyanza, western kenya, were characterized by isoenzyme electrophoresis using 12 enzymes. 12 different zymodemes of t. (t.) b. rhodesiense were isolated from patients during the 13-year period and identical stocks were also found in cattle, reedbuck (redunca redunca) and tsetse (glossina pallidipes). cattle may have played an important role in maintaining and incr ...19854095748
the development of a multipurpose trap (the nzi) for tsetse and other biting flies.new trap designs for tsetse (glossinidae), stable flies (muscidae: stomoxyinae), and horse flies (tabanidae) were tested in kenya to develop a multipurpose trap for biting flies. many configurations and colour/fabric combinations were compared to a simplified, blue-black triangular trap to identify features of design and materials that result in equitable catches. new designs were tested against conventional traps, with a focus on glossina pallidipes austen and g. longipennis corti, stomoxys nig ...200212241564
olfactory and behavioural responses of tsetse flies, glossina spp., to rumen metabolites.herbivores provide tsetse flies with a blood meal, and both wild and domesticated ruminants dominate as hosts. as volatile metabolites from the rumen are regularly eructed with rumen gas, these products could serve tsetse flies during host searching. to test this, we first established that the odour of rumen fluid is attractive to hungry glossina pallidipes in a wind tunnel. we then made antennogram recordings from three tsetse species (g. pallidipes morsitans group, g. fuscipes palpalis group a ...200919626328
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