摘要:

Abstract.Gut membrane antigens were extracted from ten isolates of the cattle tickBoophilus microplus;the antigen extracts were probed with bovine antisera and three murine monoclonal antibodies (mAbs) in Western blots and dot‐ELISA. The antisera had been obtained from cattle which were vaccinated with larval and gut extracts ofB.microplus, and which were subsequently protected (84% and 94% respectively) against challenge withB.microplus.One of the mAbs (QU13) has been demonstrated to precipitate protective antigens from the midgut ofB.microplus.Gut antigens from all ten isolates displayed similar reactivity profiles against bovine antisera and also against mAbs in Western blots. The end‐point titres of antigens in dot‐ELISA showed four‐fold variation between isolates against bovine antisera, and also against mAb QUI 3. Larval membrane antigen extracted from N‐strainB.microplusreacted with QU13 in dot‐ELISA, indicating that protective antigens are common to both larval and adult stages ofB.microplus.It was concluded that protective antigens recognized by QUI3 and antigens recognized by sera from protected cattle were conserved between the ten isolates examined, and between life

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00749.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract.The biology of nineteen taxa of African Stomoxyinae was studied during experiments with odour‐baited Vavoua traps in Nairobi National Park, Kenya. Both male and femaleStomoxyswere captured in similar numbers with C02released at 2 1/min or octenol released at 2 mg/h. Some species ofHaematoboscareacted synergistically to a combination of these two attractants, producing large increases in catch.StygeromyiaandRhinomuscaresponded only to C02, andProstomoxysdid not respond to either bait. Many different activity patterns were documented in these genera, but most activity was concentrated just prior to sunset. For example, at peak densities nearly 1500 Stomoxyinae representing fourteen taxa were caught in a single trap between 18.00 and 19.00 hours. The Stomoxyinae community was exceptionally diverse when compared with other biting fly communities. Using data from traps set with different odour baits in the park forest, Shannon‐Wiener diversity indices (H′) varied from 2.5 to 2.8, and evenness (J′) varied between 0.61 and 0.68. TheStomoxyspopulation was extremely female‐biased at the start of the rainy season, with species such asS.inornatusandS.boueticonsisting of nearly 100% females. Sex ratios equalized when the first rainy‐season generation emerged. Population doubling times estimated from trap indices were approximately 12–16 days in two habitats (forest and river

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00750.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract.Midgut homogenates prepared fromGlossina morsitans morsitans, that had previously been fed on different host blood samples, were tested for their abilities to transform bloodstreamTrypanosoma bruceiinto procyclic (midgut) formsin vitro.Compared to rat and goat blood samples, eland blood had the least capacity to support trypanosome transformation, whereas buffalo blood showed intermediate capacity. Fractionation of rat blood showed the importance of the cellular portion since both rat and eland red blood cells (RBCs) supported the process. Virtually no transformation was observed in rat and eland plasma or serum fractions. Suspending rat blood cells in eland plasma led to a reduction in parasite transformation rates. Further experiments showed that the RBC membranes were also capable of supporting the process. These results clearly show the important role played by blood, especially the red blood cells, in the transformation of bloodstream trypanosomes. In addition, the low transformation rates observed in eland blood is due to an inhibitory factor(s) present in the plasma fraction.

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00751.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract.Six cattle that had earlier exposure toDermatobia hominiswere infested experimentally with first‐instar larvae of the parasite. Skin biopsies taken at intervals were studied in wax and in plastic sections. The avidin‐biotin‐peroxidase method was used to detect the presence and localization of host immunoglobulins (Igs) G and M and antigens of first and second instar larvae ofDermatobia hominis.The larvae penetrated actively through the skin and migrated towards the subcutaneous tissues. The great numbers of eosinophils suggest that they are the most important cell in mediating damage toD.hominislarvae. The immunoglobulins bound only to dead or moulting larvae in which access to binding sites may have been altered. This could represent a morphological manifestation of a mechanism that protects larvae from the host immune response. Large amounts of soluble antigens detected along the fistulous tract may be important in the maintenance of this tract by disturbing the normal cicatrization pr

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00752.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract.Glossina longipenniswere recorded visiting and engorging on cattle in an enclosure and on a single ox in a crush using transparent electrocuting nets in an incomplete ring. Of the total flies caught, 3–6% of males and 5–6% of females in the total catches were engorged (a feeding success rate of up to 16.6% and 12.6%, respectively, depending on assumptions made about the proportion which had an opportunity to feed). Direct observation of tsetse from an observation pit showed 57% landing on the front legs, 13% on the hind legs, and 11 % on the belly of the host. The largest number of bloodmeals was taken from the front legs, although only 14% of landings there terminated in feeding; a higher proportion of the flies alighting on the hind legs and flank succeeded in feeding (28% and 21% respectively).Glossina longipenniswere attracted to targets baited with ox odour from an underground pit in a dose‐dependent manner. Odour of humans was much less attractive toG.longipennisthan that of oxen (for equivalent biomass). Analysis of bloodmeal samples from tsetse caught in two sites on die ranch showed thatG.longipennispreferentially feeds on suids, bovids and hippopo

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00753.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract.At 340–360 km North of the Arctic Circle in Norway,Hypoderma tarandi(L.) andCephenemyia trompe(Modeer) females were caught in baited traps from 10 July to 21 August. During three summers, adverse climatic conditions inhibited flight activity of these oestrids on 56–68% of the days. Flies were not caught prior to or after these dates, nor at winds above 8 m/s, temperatures below 10d̀C, light intensities below 20,000 lux, or during periods of rain or snow. C02‐baited insect flight traps caught significantly moreH. tarandifemales than non‐baited traps. However, neither a white reindeer hide or reindeer interdigital pheromone glands enhanced the attraction of C02toH. tarandiorC. trompe. Hypoderma tarandifemales also were attracted to mobile people, but not to stationary individuals. There were no significant differences in the numbers ofC.trompeorH.tarandicaught in C02‐baited traps in a birch/willow woods, on the treeless vidda (=tundra‐like biome), or at woodsrvidda ecotone sites. Flies were caught in traps on days when the nearest reindeer herds were 25–100 km away. Significantly moreH.tarandiandC.trompewere caught from 09.30 to 14.30 hours than from 14.30 to 19.30 hours; no flies were caught from 20.00 to 07.00 hours (Norwegian Standard Time = NST). Because COz‐baited traps caught from hundreds to thousands of mosquitoes, blackflies andCulicoidesmidges, when climatic conditions inhibited oestrid activity, reindeer aggregations and movements attributed to insect attacks during warm sunny days may be largely in response to attacks byH.ta

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00754.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract.Dissection of flies caught in northern Norway revealed that only mated, gravid females ofH.tarandi(L.) and larviparousC.trompe(Modeer) were caught in host‐mimicking C02‐baited traps. Trapped females had the same gonotrophic and fat body (FB) conditions as females caught on and around reindeer. Most trapped females of both species were of middle to old age, having only one‐half to no FB reserves left and only a few to moderate numbers of eggs or larvae remaining. Most young females trapped also had previously oviposited or larviposited at least once, and some newly eclosed, mated females were present throughout the fly season. Based on the known location of reindeer herds, it was evident that trapped flies that had recently oviposited or larviposited had dispersed into the trapping area from 25–100 km away. Declining FB reserves sustained wild‐caughtC.trompefemales (andin uterolarvae) in the laboratory for 14 days andH.tarandifemales for 18 days. Reserve FB also was depleted during long flights. Females of both species that flew for the longest times (5.1–11.7 h) on a laboratory flight mill had low FB reserves, but nearly maximum numbers of eggs or larvae. Conversely, most females that flew for less than 5 h on the flight mill had little or no FB remaining, and few eggs or larvae. The large FB reserves accumulated as larvae feed in the vertebrate host enable the non‐feeding adults to survive and infect their hosts even after prolonged periods of flight‐inhibiting clim

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00755.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract.Following the discovery of four cases of African human trypanosomiasis, an entomological survey was conducted along the Mouhoun river in southwest Burkina Faso to collectGlossina palpalis gambiensisandG.tachinoides.Among 226 flies dissected, 4.87% (eleven individuals) were infected in midgut or proboscis, but never in the salivary glands. Polymerase chain reaction analysis was undertaken, and was able to characterize all the proboscis infections, and half of the midgut infections. OnlyTrypanosoma simiaeandT. vivaxwere found in the organs of infected flies, in single or mixed‐species infections. Ten more flies, negative with parasitological examination, were tested withTrypanozoonprimers and remained negative. The epidemiological significance of the absence ofT.bruceigroup infections in wild tsetse populations and the presence ofT.simiaeinG.p.gambiensisare discusse

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00756.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract.Four species of ticks found to infest 1391 American mink(Mustela vison)in Britain in five years were, in declining order of frequency,Ixodes hexagonus, Ixodes canisuga, Ixodes ricinusandIxodes acuminatus. Ixodes hexagonusandI.canisugaoccurred on 40% and 2.5% of mink respectively. Infestation rates (the proportion of infested mink) of adult females, nymphs and larvae were similar and tended to be lower in summer. The distribution of infestation size (the number of ticks per host) for adult females describes a negative binomial. The mean infestation size of nymphs varied with the sex of the host and was 5.2 for males and 4.2 for females. Mink are competent hosts for /.hexagonus.

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00757.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract.Between 1920 and 1930, four species of parasitoid Hymenoptera(Tachinaephagus zealandicus, Alysia manducator, Nasonia vitripennisandBrachymeria ucalegon)were imported to New Zealand as an aid in the control of the blowflies causing myiasis in sheep (flystrike). Their long‐term effects have never been investigated and the extent to which they were successful in establishing and enlarging their ranges has been given scant regard over the last 60 years. A long‐term epidemiological study of flystrike in New Zealand between 1986 and 1996 obtained 4061 samples of blowfly larvae from flystruck sheep and carrion and overall 1.1% of these larval samples (most from the North Island) were found to be parasitized.Tachinaephagus zealandicusandA. manducatorwere present in field strikes, together with the endemicAphaereta aotearecently found to be a parasite of calliphorids. The endemic speciesPhaenocarpa antipodawas found in association with carrion but not flystrike. NeitherN.vitripennisnorB.ucalegonwere isolated from larvae in field strikes, the former because it parasitizes only pupae and the latter may be extinct as it has not been sighted since its introduction in 1919.It is concluded that if parasitoid wasps are able to locate and parasitize blowfly larvae on struck sheep, then their parasitism rate on more accessible larvae on carcases may be correspondingly greater. For this reason their scope for use in integrated management of flystrike could be increased by culturing and field rele

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1996.tb00758.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY