bluuebunny/crossref_metadata_2025 huggingface dataset:
Temperature‐dependent development and parasitism rates of four species of Pteromalidae (Hymenoptera) parasitoids of house fly (Musca domestica) pupae
Authors: MANN J. A. , AXTELL R. C. , STINNER R. E.
Published: March 2008

Abstract. Parasitoid development, parasitoid‐induced host mortality and parasitoid progeny emergence were determined at five constant temperatures for Muscidifurax raptor Girault and Sanders, Muscidifurax zaraptor Kogan and Legner, Spalangia earneroni Perkins and Spalangia endius Walker using pupae of the house fly, Musca domestica L., as hosts. At temperatures of 20, 25, 30 and 35oC the median development times (days from oviposition to adult emergence), respectively, were M.raptor (28.4, 20.7, 14.3, 14.5), M.zaraptor (30.6, 22.8, 14.1, 14.2), S.cameroni (55.6,35.2, 21.8,25.0) and S.endius (52.4, 31.5,16.3,14.6). All species failed to emerge at 15oC. Using densities of five parasitoids and 100 hosts and a 24 h exposure period, Muscidifurax species oviposited at a greater rate over a wider range of temperatures than Spalangia species. At 15, 20, 25, 30 and 35oC the mean number of pupae killed per parasitoid were, respectively, M.raptor (1.4, 7.4,10.5, 13.7,14.1), M.zaraptor (0.0, 3.3, 8.9,14.4,15.0), S.cameroni (0.0, 7.8, 11.0, 11.9, 7.4), S.endius (0.6, 4.0, 7.5, 12.0, 11.7), and means of the number of parasitoid progeny per parasitoid were, respectively, M.raptor (0.2, 5.2, 7.9, 11.8, 11.6), M.zaraptor (1.3, 4.4, 8.2, 13.0, 13.7), S.cameroni (0.0, 2.4, 4.7, 5.1, 1.0), S.endius (0.0, 0.9, 3.4, 7.5, 4.9). Development and ovipositional activity in S.cameroni was strongly inhibited at 35oC. The model by Sharpe & DeMichele (1977) was used to describe temperature‐dependent development and the number of parasitoid progeny produced per parasitoid at temperatures of 15–30oC in all species.
Effects of host age, host density and parent age on reproduction of the filth fly parasite Urolepis rufipes (Hymenoptera: Pteromalidae)
Authors: MATTHEWS J. R. , PETERSEN J. J.
Published: March 2008

Abstract. Urolepis rufipes Ashmead, a pteromalid wasp, was recently discovered parasitizing house fly and stable fly pupae in eastern Nebraska dairies. Studies have been conducted on the biology of this parasite to evaluate its potential as a biological control agent of stable flies (Stomoxys calcitrans (L.)) and house flies (Musca domestica L.). House fly pupae were suitable as hosts for U. rufipes at all ages; however, significantly higher parasitism occurred on host pupae aged 96–120 h. Parasite‐induced mortality (host mortality without progeny production) was higher than for other pteromalid parasites of filth flies under similar conditions. Parasitism increased with parasite‐host ratio at 20oC; however, the opposite was noted at 30oC for parasite‐host ratios ranging from 5:50 to 50:50. Fly eclosion decreased as parasite‐host ratio increased at 20oC, and no host eclosion occurred at the highest parasite‐host ratios (20:50 and 50:50) at 30oC. Females produced an average of 18.6 female and 7.6 male progeny. 88% of the progeny were produced during the first 6 days post parental eclosion. The short life span, low progeny emergence rate and high per cent host eclosion, in comparison with other parasite species, suggests that the Nebraska strain of U. rufipes may not an effective biological control agent of house flies.
Detection and selection of organophosphate and carbamate resistance in Culex quinquefasciatus from Saudi Arabia
Authors: AMIN A. M. , PEIRIS H. T. R.
Published: March 2008

Abstract. Resistance to a number of organophosphorus insecticides and the carbamate propoxur has been detected in a field population of Culex quinquefasciatus Say from Jeddah, Saudi Arabia. Cross resistance studies indicate that the same mechanism(s) may produce resistance to the full range of these compounds.
Bait‐fed adult Culex pipiens carry the larvicide Bacillus sphaericus to the larval habitat
Authors: SCHLEIN YOSEF , PENER HEDVA
Published: March 2008

Abstract. Sugar meals of plant origin are a basic component of mosquito diet. We show that sugar baits have potential as vehicles for control agents. When Culex pipiens L. resting‐sites were sprayed with sucrose solution, with or without incorporation of the larval toxicant Bacillus sphaericus Neide, 47% of female mosquitoes fed in situ. Dispersing B.sphaericus‐carriei mosquitoes caused larval mortality in breeding‐sites 60–100 m from the sprayed resting‐sites. The effect was not seen where no adults rested in sparse vegetation above larval habitats. This approach may be useful for the application of biological control agents against mosquitoes in biotopes where the adults and larvae are juxtaposed.
Rabbit antibody responses to experimental infestation with Dermatobia hominis
Authors: LELLO E. DE , BOULARD C.
Published: March 2008

Abstract. The three larval stages of Dermatobia hominis (Linnaeus) have been evaluated for their immunogenicity by ELISA and immunodiffusion (ID) using sera from experimentally infested rabbits. During a primary infestation, first instar D.hominis were found to cause most reaction and allowed the earliest diagnosis by ELISA. An inhibition of the antibody response against second and third instars was observed. The inhibition disappeared after departure of the larvae from the host. In experimentally immunized hosts the antibody response, following challenge, was highest against second and third instar antigens. Antibody remained elevated during the infestation but fell immediately after the larvae had left the host.
Skin test to detect resistance of cattle to Rhipicephalus appendiculatus ticks
Authors: WALKER ALAN R. , FLETCHER JUNE D.
Published: March 2008

Abstract. The evaluation of a skin test to detect acquired resistance to Rhipicephalus appendiculatus Neumann ticks is described. An extract of salivary glands of partially fed female R.appendiculatus was prepared by dissection, sonication and filtration and used for intra‐dermal injection. Tests were carried out on twelve calves of known resistance to R.appendiculatus and on twelve naive calves to establish threshold values for positive reactions. Four rabbits naive to ticks were skin tested repeatedly to assess immunogenicity of the test. Reactions to the test at 1 h and at 24 h after injection were significantly correlated with resistance. The correlation was higher with the reactions at 24 h. Rabbits were immunized by the test but the reactions never exceeded the positive threshold. Further development by field testing is recommended.
The effect of Amblyomma variegatum on liveweight gain of cattle in Zambia
Authors: PEGRAM R. G. , OOSTERWIJK G. P. M.
Published: March 2008

Abstract. The effect of the tick Amblyomma variegatum Fabricius on liveweight gain (LWG) on yearling cattle over 16 weeks was evaluated under quasi‐natural conditions. Early in the exposure period when animals may have been in a state of suppressed metabolism, the effect of tick feeding on LWG was negligible. Overall, however, the difference in LWG between tick‐free and tick‐infested groups of cattle was 4.95 kg after 16 weeks. This difference between the groups was used to estimate a lower LWG of 48–63 g due to each engorging female tick.
Equine Culicoides hypersensitivity in Florida: biting midges aspirated from horses
Authors: GREINER ELLIS C. , FADOK VALERIE A. , RABIN EDWIN B.
Published: March 2008

Abstract. Nine species of Culicoides were aspirated from horses in Florida during the second phase of a study of equine Culicoides hypersensitivity (CHS). Approximately 90% of the 2933 midges were Culicoides insignis Lutz, 4% were C.stellifer (Coquillett), 3% were C.niger Root and Hoffman, 2% were C.alachua Jamnback and Wirth and the remaining 1% included C.venustus Hoffman, C.scanloni Wirth and Hubert, C.lahillei Iches (=C.debitipalpis Lutz), C.pusillus Lutz, and C.edeni Wirth and Blanton. Culicoides were sampled on seven farms located throughout Florida. The location and seasonality of lesion development on horses with CHS correlated with the Culicoides spp. collected directly from the horses as to their sites of attack, their seasonality and geographical distribution.
Testing Anopheles albimanus for genetic linkage of insecticide resistance genes by combining insecticide bioassay and biochemical methods
Authors: LINES J. D. , FfRENCH‐CONSTANT R. H. , KASIM S. H.
Published: March 2008

Abstract. A microtitre‐plate assay which distinguishes propoxur‐resistant from susceptible Anopheles albimanus Weidemann was used to test for linkage between the genes for propoxur‐ and dieldrin‐resistance. The adult progeny of a backcross between a doubly‐resistant colony and a fully susceptible colony were exposed in conventional test kits to the standard discriminating dose of dieldrin, and kept in the insectary overnight. Both live and dead insects were then assayed individually for propoxur‐resistance.

The results showed that heterozygotes for propoxur‐resistance could be reliably distinguished from susceptibles whether or not they had been killed up to 24 h previously by dieldrin treatment. In this way all the backcross progeny could be scored at both resistance loci, and all four genotypic classes identified. Resistant and susceptible alleles at the two loci were inherited independently, demonstrating the absence of linkage.

The usual method of testing for linkage between resistance genes is inefficient and open to bias, because insects have to be exposed to each insecticide in turn, and only half of them can be scored at both loci. The method shown here avoids these drawbacks.
Intraspecific variation in the cuticular hydrocarbons of the sandfly Phlebotomus perfiliewi from Italy
Authors: PHILLIPS A. , MILLIGAN P. J. M. , MAROLI M. , LANE R. P. , KAMHAWI S. , BROOMFIELD G. , MOLYNEUX D. H.
Published: March 2008

Abstract. The cuticular hydrocarbons of Phlebotomus perfiliewi Parrot from representative localities on both sides of Italy show contrasts which support the view of Ward et al. (1981) that there are distinguishable populations of this sandfly on the Adriatic and Tyrrhenian coasts. It is suggested that the Appennine mountains form a barrier between the Adriatic and Tyrrhenian populations.

A third distinct hydrocarbon type of P.perfiliewi was detected in Calabria, southern Italy, where contact between the Adriatic and Tyrrhenian types of flies is most likely to occur. P.perfiliewi from a trans‐Appennine pass were also of the Calabrian hydrocarbon type.

These hydrocarbon contrasts between allopatric populations of P.perfiliewi may result from clinal variation across the Appennines, associated with different host preferences, or they may represent apomictic populations with differential mate recognition systems.
Ectoparasites of commensal rodents in Sulawesi Utara, Indonesia, with notes on species of medical importance
Authors: DURDEN LANCE A. , PAGE BERNARD F.
Published: March 2008

Abstract. Ectoparasite records are presented for four species of commensal murid rodents (Rattus rattus palelae Miller & Hollister, R.argentiventer (Robinson & Kloss), R.exulans (Peale) and Mus musculus castaneus Waterhouse) in Sulawesi Utara, with particular reference to the potential for these arthropods to bite and transmit pathogens to humans. The flea, Xenopsylla cheopis (Rothschild), was most common on R.r.palelae and is capable of transmitting plague and other pathogens to humans although no current foci for these diseases are known in Sulawesi. Hoplopleura pacifica Ewing and Polyplax spinulosa (Burmeister) sucking lice parasitized all three Rattus species although H.pacifica was mainly associated with R.exulans and P.spinulosa with R.r.palelae. These lice do not bite humans but may be intramurid vectors of murine typhus and other zoonoses. The mites Laelaps echidnina Berlese and L.nuttalli Hirst were both collected; the latter was recorded from all four murid species, mainly R.exulans. The mite Ornithonyssus bacoti Hirst was rare. Only one chigger mite, Walchiella oudemansi (Walch), was retrieved from murids (from R.exulans) and a single Leptotrombidium deliense (Walch) chigger was taken from a human subject. Although L.deliense is a significant vector of scrub typhus, a disease known from Sulawesi, the L.deliense– R.argentiventer relationship frequently noted in the ecology of this rickettsial disease, was not evident in this survey. Other ectoparasites collected from murids were the ticks, Ixodes granulatus Supino (first record for Sulawesi), Haemaphysalis sp. and Dermacentor sp., the mites Myocoptes musculinus (Koch) and Listrophoroides cucullatus (Trouessart), acarids and a uropodid. Additional ectoparasites noted on humans were the tick Amblyoma babirussae (Schulze), the scabies mite Sarcoptes scabiei L. and the head louse Pediculus humanus capitis De Geer.
Evaluation of monoclonal antibodies against Plasmodium vivax sporozoites for ELISA development
Authors: WIRTZ R. A. , CHAROENVIT Y. , BURKOT T. R. , ESSER K. M. , BEAUDOIN R. L. , COLLINS W. E. , ANDRE R. G.
Published: March 2008

Abstract. Nine monoclonal antibodies (MAbs) developed against Plasmodium vivax (Grassi & Feletti) salivary gland sporozoites were evaluated for use in an enzyme‐linked immunosorbent assay (ELISA), using sporozoites developed in Anopheles dims Peyton & Harrison An.gambiae Giles and An.maculatus Theobald. Four of the antibodies were unsuitable due to the low sensitivity of the resulting assays or the requirement for high concentrations of capture antibody. An additional two MAbs were rejected because they resulted in assays with high background absorbance, attributed to self‐binding. Of the three remaining MAbs, the use of Navy vivax sporozoite (NVS) 3 resulted in an ELISA with the highest sensitivity and the lowest concentration requirement for capture antibody. Assay sensitivity varied with sporozoite strain indicating possible quantitative epitope heterogeneity. None of the MAbs cross‐reacted with the heterologous sporozoites tested by immunofluorescence antibody assay (IFA). The IFA activity was not an indicator of ELISA sensitivity. The use of MAb NVS 3 in a standardized ELISA method resulted in an assay 10 times more sensitive than reported previously for P. vivax sporozoites, with a detection limit of fewer than 100 sporozoites per mosquito.
Automatic recording of flea activity
Authors: GREENWOOD M. T. , CLARK F. , SMITH J. S.
Published: March 2008

Abstract. An Insect Activity Monitor was created to measure the behavioural responses of fleas (Siphonaptera). The apparatus allows for a range of visual, chemo‐ and mechanoreceptor cues to be presented. The jumping response is detected by counting amplified pulses produced as the fleas land on a stretched membrane held over a microphone. Horizontal movements are detected using a system of infra‐red beams and phototransistors which, when broken, are counted as a measure of activity.

The apparatus was tested using Ceratophyllus hirundinis (Curtis), Ceratophyllusfarreni (Rothschild) and Ceratophyllus rusticus (Wagner), co‐inhabiting species from the nests of the house martin (Delichon u.urbica L.). No unaided emigration or immigration has been demonstrated in these species (Clark, 1988) and much of their time is spent confined to the darkness of the nest. In addition to species contrasts, females were more active than males and fleas were more active at 25oC than at 18oC.

The more active bird flea Ceratophyllus garei (Rothschild) from the nest of pheasant (Phasianus colchicus L), was tested for responses to light of varying intensity. Activity was stimulated by white light, but not proportional to light intensity.
Glossina fusca group tsetse as vectors of cattle trypanosomiasis in Gabon and Zaire
Authors: LEAK S. G. A. , COLARDELLE C. , D'IETEREN G. , DUMONT P. , FERON A. , JEANNIN P. , MINENGU M. , MULUNGU M. , NGAMUNA S. , ORDNER G. , SAUVEROCHE B. , TRAIL J. C. M. , YANGARI G.
Published: March 2008

Abstract.

he significance of Glossina fusca group tsetse flies as vectors of cattle trypanosomiasis was examined using biconical traps to survey tsetse populations at one site in Gabon and two sites in Zaire.

Mean trypanosome infection rates in G.tabaniformis Westwood over the study period ranged from a minimum of 8.9% at one site to a maximum of 17.7% at another. The mean infection rate in G.nashi Potts was 6.0%.

Up to 49% of bloodmeals of G.tabaniformis were from cattle. Trypanosome prevalence in cattle where G.tabaniformis appeared to be the main vector was 9.5% and 5.4% at the Mushie and OGAPROV ranches, respectively.

A highly significant positive correlation was found between tsetse challenge and trypanosome prevalence in N'Dama cattle across sites. Tsetse challenge was defined as the product of tsetse relative densities, trypanosome infection rates in the flies and the proportion of feeds taken by them from cattle. Thus, G.tabaniformis can be an important vector of pathogenic Trypanosoma species in cattle.
Development of a low‐cost tsetse trap and odour baits for Glossina pallidipes and G.longipennis in Kenya
Authors: BRIGHTWELL R. , DRANSFIELD R. D. , KYORKU C.
Published: March 2008

Abstract. 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. longi‐pennis Corti. Modifications included a lower dose rate of acetone, a new cage design and raising the trap about 15‐20cm. 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.pallidipes. Adding an additional metre of blue cloth to one side of the trap increased catches of females of both species by about 60%. Traps baited with synthetic phenols yielded similar numbers of G.pallidipes and significantly more G.longipennis than those baited with natural cow urine. The latter difference was not apparent when octenol was also used, so cow urine was retained as one of the odour baits in preference to the imported phenols. Although octenol increased catches of G.pallidipes by only about 30%, catches of G.longipennis were increased 2–4‐fold, making it a very useful attractant for the latter species. The cost of the trap/odour‐bait system was estimated to be US$8.5 per unit per annum. The economics of this method of tsetse control are discussed.
Induction of dominant lethal mutations for control of the facefly, Musca autumnalis DeGeer
Authors: MANSOUR Y. M. , KRAFSUR E. S.
Published: March 2008

Abstract.

Application of the sterile insect technique (SIT) to the facefly, Musca autumnalis DeGeer, is considered.

Six‐day‐old pupae were exposed to ionizing irradiation at doses in the range 100–1600 rads, each treatment being replicated six times.

Eclosion was unaffected but fecundity and fertility was inversely proportional to the radiation dose.

1600 rads gave 97% dominant lethality of sperm in treated males and suppressed ovarian development in females. Irradiated flies did not recover fertility.

Irradiation of males and females did not affect insemination rates.

Sterile males showed a decline in longevity and reduced mating competitiveness.

Local eradication of M. autumnalis is considered to be feasible if sufficient diapausing sterile flies are stockpiled and released in early spring, followed by additional releases of non‐diapausing flies in late spring and early summer, with further releases of diapausing sterile flies in late summer and autumn.
Malathion and pyrethroid resistance in Culex quinquefasciatus from Cuba: efficacy of pirimiphos‐methyl in the presence of at least three resistance mechanisms
Authors: BISSET J. A. , RODRIGUEZ M. M. , HEMINGWAY J. , DIAZ C. , SMALL G. J. , ORTIZ E.
Published: March 2008

Abstract. Use of malathion for mosquito control in Cuba for 7 years up to 1986 has selected for elevated non‐specific esterase and altered acetylcholinesterase (AChE) resistance mechanisms in populations of the pest mosquito Culex quinquefasciatus Say. These mechanisms are still present in relatively high frequencies in the Havana area, despite the replacement of malathion by pyrethroid insecticides for the last 3 years in the mosquito control programme.

Samples of Culex quinquefasciatus populations from within a 100 km radius of Havana had high levels of resistance to malathion and lower levels of resistance to propoxur, but there was little or no cross‐resistance to the organophosphorus insecticide pirimiphos‐methyl.

Selection with malathion for twenty‐two consecutive generations in the laboratory increased the level of malathion resistance to 1208‐fold and propoxur level to 1002‐fold, but the maximum level of pirimiphos‐methyl resistance was only 11‐fold.

Pirimiphos‐methyl is still operationally effective, despite the resistance mechanisms segregating, so this insecticide if used for control is unlikely to select either of the known resistance factors directly in the field population.

Since 1986, pyrethroids have been used extensively, and low levels of pyrethroid resistance were detected in two of five field population samples tested.

Malathion selection did not increase the level of pyrethroid resistance, which indicates that one or more distinct pyrethroid resistance factors are now being selected in the field populations of Culex quinquefasciatus.
Comparative use of bendiocarb and DDT to control Anopheles pseudopuncitpennis in a malarious area of Mexico
Authors: LOYOLA ENRIQUE G. , VACA MIGUEL A. , BOWN DAVID N. , PÉREZ ENRIQUE , RODRIGUEZ MARIO H.
Published: March 2008

Abstract. The state of Sinaloa has one of the highest and most persistent malaria transmission levels in Mexico. Due to this situation, with resistance of the vector Anopheles pseudopunctipennis Theobald to DDT, the carbamate insecticide bendiocarb was evaluated as an alternative to DDT for residual house‐spraying in village‐scale trials during 1985–87. Application rates of the active ingredient per square metre of sprayable surface (ai/m2) were 0.4 g bendiocarb 80% wettable powder (80WP) and 2g DDT 75% WP.

Both insecticides failed to control mosquito populations. Human‐bait mosquito densities were not altered as a result of insecticide spraying and human‐bait collected mosquito mortality rates were low, suggesting little pre‐biting insecticide contact due to avoidance or insufficient resting time indoors. Lower densities of indoor‐resting mosquitoes were observed with DDT as opposed to bendiocarb treated houses. Anopheline mortality was higher (98–100%) when exposed for 1 h to 1% bendiocarb in standard WHO susceptibility tests and wall bioassays. Mortality‐rates of 15–48% due to lh exposure to 4% DDT indicated that this insecticide may continue to be partially effective. House curtain and mark‐recapture mosquito studies indicated that DDT produced higher excito‐repellency than bendiocarb, as reflected by more mosquito landings but lower feeding rates, shorter resting period and earlier exit time from DDT sprayed houses.

In the absence of insecticide, more than 50% of blood‐fed An.pseudopunctipennis females exited from houses within 2–Ah of release, showing exophilic behaviour. The outdoor/indoor density ratio indicated that the majority were exophagic. These behavioural characteristics limit the usefulness of any residual insecticide against An.pseudopunctipennis.
Prehibernation diet and reproductive condition of female Anopheles messeae in Sweden
Authors: THOMAS G. , JAENSON T. , AMENESHEWA BIRKINESH
Published: March 2008

Abstract.

Blood and sugar feeding in the mosquito Anopheles messeae Falleroni were investigated near Uppsala, Sweden, from 1981 to 1985, with emphasis on prehibernation diet.

Fructose, indicating plant feeding, was present in females of all ovarian stages, from April to October, and contributed to fat body development in non‐gonoactive females before hibernation.

An.messeae males and females (inseminated and uninseminated) were observed feeding on floral nectaries of the plants Achillea millefolium L. and Tanacetum vulgare L. at night during August.

Gonotrophic dissociation started in some females in July, and by the end of September all females were inseminated and nulliparous but non‐gonoactive.

Animal sheds were used as diurnal resting sites of non‐gonoactive, prehibernating female An. messeae. Among recently fed mosquitoes in that group, 85% were gut positive for fructose and 15% for blood. Most of them showed negative host tropism, indicating that bloodfeeding is not a prerequisite for hibernation.

Survival rates of bloodfed (48 ± 31 days) and non‐bloodfed (42 ± 21 days) females, collected from a cattle shed in September and kept caged without food or water in a store house, were not significantly different. This indicates that bloodfeeding may occur facultatively before hibernation but does not affect longevity and survival.

If overwintering is possible for bloodfed An.messeae females, they would be more likely vectors of pathogens such as Batai virus.
Life history of Spalangia gemina Boucek (Hymenoptera: Pteromalidae), a fast‐breeding microhymenopteran pupal parasitoid of muscoid flies
Authors: MORGAN PHILIP B. , BERTI‐FILHO EVONEO , COSTA VALMIR A.
Published: March 2008

Abstract. Laboratory studies at 25.5oC and 70–75% r.h. demonstrated that the average daily survival rate for females of the parasitoid Spalangia gemina Boucek (Hymenoptera: Pteromalidae) was 0.907 over a 20‐day period, with 50% mortality in 17.3 days. Mean immature developmental time of S. gemina was 22 days and the population growth rate was c. 40‐fold per generation. The females successfully parasitized 1‐, 2‐ and 3‐day‐old pupae of Musca domestica L. and parasitism of 98–100% was obtained at parasitoid to host ratios of 1:0.5‐2.5. Parasitism of 81–87% was obtained at parasitoid to host ratios of 1:10. The male to female sex ratio was 1:1.59. S.gemina appears to have advantages over other Spalangia spp., which have immature development times of 28–32 days under comparable conditions, for the biological control of Muscidae.
Development of Onchocerca volvulus microfilariae injected into Simulium species from Cameroon
Authors: EICHNER M. , RENZ A. , WAHL G. , ENYONG P.
Published: March 2008

Abstract. Microfilariae (mff) of the savanna and forest strains of Onchocerca volvulus (Leuckart) were injected intrathoracically into adult females of Simulium damnosum Theobald sensu stricto, S.sirbanum Vajime & Dunbar, S.squamosum Enderlein and S.mengense Vajime & Dunbar. Nine days post infection (pi) 27–29% of the savanna mff and 31–38% of the forest strain had developed to third‐stage larvae (L3), irrespective of the fly species, size or injection dose (5, 10 or 15 mff). Savanna flies supported the development of forest O. volvulus better than forest flies, in contrast to the results after per os infections. Therefore, in these four species of the S.damnosum complex from Cameroon, the peritrophic membrane is considered to be the main factor limiting the success rate of microfilarial development following the ingestion of blood infections, while the fly's haemolymph and intracellular environment play minor roles.
The feeding behaviour, activity and trappability of wild female Glossina pallidipe in relation to their pregnancy cycle
Authors: RANDOLPH SARAH E. , ROGERS DAVID J. , KIILU JOHN
Published: March 2008

Abstract. Female Glossina pallidipes Austen trapped with baited NG2B traps were subjected both to detailed ovarian dissection and to nutritional analysis. Using a calibration curve derived from dissected wild‐caught, laboratory‐held flies, the field females were assigned by discriminant analysis to each day of the pregnancy cycle. Field females were most available to NG2B traps while carrying the first instar larva. The nutritional characteristics of trapped field females over the pregnancy cycle lead to the following main conclusions, (i) Fat levels increase most rapidly during the egg in utero stage, while CRDW increases significantly only during the larval stages, culminating in a 4mg increase during the last day of the third larval instar. (ii) The haematin content of the flies indicates that females feed at approximately 3‐day intervals and may feed on any day of the pregnancy cycle, (iii) The estimated time of feeding during the day corresponds with the observed time of peak activity, both of which are earlier in the day later in the pregnancy cycle, (iv) The rate of fat usage reveals significantly greater flight activity on day 5 of the cycle than on other days, agreeing with the high trappability on this day, and overall females appear to use fat at twice the rate of males. Reproductive data provide a much more accurate picture of the relative sampling efficiency than do nutritional data, although the latter reveal the general trends correctly.
Control of the haematophagous fly Hippobosca maculata, a serious pest of equines, by deltamethrin
Authors: PARASHAR B. D. , GUPTA G. P. , RAO K. M.
Published: March 2008

Abstract. This study reports the results of both a small‐scale and a large‐scale field treatment to assess control of the haematophagous fly Hippobosca maculata Leach a serious pest of equines in a stud in India using a deltamethrin based formulation, Butox®. In the small‐scale field trial application of 2 litres of deltamethrin at 0.001‐0.003% concentration gave 90–100% control over 30 days. At 0.004% and 0.005% concentrations complete control was recorded for 45 and 90 days respectively. Mass application of 2 litres of 0.005% deltamethrin to equines and bovines controlled infestations of H.maculata for 1 year.
Ixodes (Pholeoixodes) hexagonus, an efficient vector of Borrelia burgdorferi in the laboratory
Authors: GERN LISE , TOUTOUNGI LINA N. , HU CHANG MIN , AESCHLIMANN ANDRE
Published: March 2008

Abstract. Borrelia burgdorferi Johnson et al. was first isolated from the midgut of Ixodes dammini Spielman et al. in the U.S.A. and from the midgut of Lricinus (L.) in Europe. I.ricinus was considered to be the only tick vector of this borrelia, in Europe, until I.hexagonus Leach, the hedgehog tick, was found to harbour spirochaetes. This paper reports an evaluation of the vector competence of I. hexagonus for the spirochaete B. burgdorferi. Transovarial and trans‐stadial survival were demonstrated and the spirochaete was transmitted to laboratory mice via the bites of trans‐stadially infected I.hexagonus females.
Synthetic DNA probes for the identification of sibling species in the Anopheles gambiae complex
Authors: HILL SUSANNAH M. , URWIN RACHEL , KNAPP TERESA F. , CRAMPTON JULIAN M.
Published: March 2008

Abstract. The cloned DNA sequences pAnal, pAnql and pAnml4, which may be used to distinguish between at least five of the six species in the Anopheles gambiae Giles complex of Afrotropical malaria vector mosquitoes, have been sequenced. Each clone was found to possess a series of repeated sequences of 41, 30 and 163 bases respectively. In pAnql and pAnml4 the repeats were in direct tandem array, whilst in pAnal the repetitive sequence was found to be interspersed by 15–17 variable bases. A comparison of a number of copies of each of the repetitive sequences within the three clones enabled the definition of the consensus sequence for each repetitive element. Based on these consensus sequences, three oligonucleotides of 21, 23 and 26 bases were derived from pAnal, pAnql and pAnml4 respectively. When tested as probes against DNA dot‐blots and squash‐blots of mosquito specimens, each oligonucleotide retained the same species‐specificity as the original clones from which they were derived. The radioactively labelled oligonucleotides were able to detect as little as 5 ng of target genomic DNA in an overnight autoradiographic exposure. The synthetic DNA probes will form the basis of a simplified system for the field identification of Anopheles gambiae sibling species specimens.
Pyrethroid‐treated bednet effects on mosquitoes of the Anopheles gambiae complex in The Gambia
Authors: LINDSAY S. W. , ADIAMAH J. H. , MILLER J. E. , ARMSTRONG J. R. M.
Published: March 2008

Abstract. The response of Anopheles gambiae complex mosquitoes to men sleeping under insecticide‐impregnated or untreated bednets in six verandali trap huts was studied during the dry season in The Gambia. With this type of hut it was possible to collect live and dead indoor‐resting mosquitoes and estimate the number of wild mosquitoes which entered, bloodfed on man, and exited each night. Bednets were treated with emulsions targetted to leave deposits of 25mg/m2 lambda‐cyhalothrin, or 5,50 or 500 mg/m2 permethrin, diluted from emulsifiable concentrates (EC), or a blank formulation similar to the EC except that the permethrin was omitted; the sixth net was left untreated. Nets and sleepers were rotated between huts on different nights, the design being based on a series of Latin squares and conducted double‐blind.

Permethrin‐impregnated bednets deterred mosquitoes from entering the huts. The degree of deterrency was proportional to the dosage of permethrin. This effect was also caused by the blank formulation and therefore attributed to other components of the formulation, rather than to the permethrin itself. The net impregnated with 500 mg permethrin per square metre gave the best individual protection, reducing mosquito bloodfeeding by 91% compared with untreated nets. However, lambda‐cyhalothrin was proportionately more insecticidal than permethrin at doses of equivalent deterrency. At this stage of research, it remains conjectural whether chemical deterrency or killing of malaria vectors is better for community protection.
Lectin and peritrophic membrane development in the gut of Glossina m.morsitans and a discussion of their role in protecting the fly against trypanosome infection
Authors: LEHANE M. J. , MSANGI A. R.
Published: March 2008

Abstract. Newly emerged Glossina m.morsitans Westwood tsetse flies lack a peritrophic membrane which develops to fully line the midgut after c. 80‐90h. Midgut lectins are mainly associated with the peritrophic membrane. Lectin levels in the blood‐free gut of adult flies rise slowly up to 8 days and then rapidly to at least 14 days post‐eclosion (when the last of our recordings was made). Despite starving flies for 4 days prior to the agglutination assay, gut lectin levels in older flies are 100–200 times more than those in newly ecloded flies. This is inconsistent with the idea that there is a simple relationship between lectins and the protection of tsetse flies against trypanosome infection. Various theories put forward to account for age‐dependent variation in the ability of tsetse to become infected with trypanosomes are discussed in the light of these findings.
The Cliff Swallow Bug Oeciacus vicarius (Hemiptera: Cimicidae) in Florida: ectoparasite implications for hole‐nesting birds
Authors: LOY JENELLA , REGAN TIMOTHY W.
Published: March 2008

Abstract. In May 1988, ten juvenile birds, not yet ready to fledge, jumped to their death from a colony of the purple martin, Progne subis near Okeechobee City, Florida. The martin house and nestlings were found to be infested with ectoparasitic Oeciacus vicarius Horvath, the cliff swallow bug, not previously reported from Florida. This ectoparasite infestation apparently led to early abandonment of two houses by the adult martins. Oeciacus vicarius therefore represents a possible threat to all hole‐nesting birds.
Relations between Anopheles darlingi breeding habitats, rainfall, river level and malaria transmission rates in the rain forest of Suriname
Authors: ROZENDAAL J. A.
Published: March 2008

Abstract. Irregular peaks of P.falciparum malaria incidence were monitored in Suriname during 1982‐86. An attempt is made to correlate these fluctuations of malaria rates with rainfall and river level in relation to the periodic availability of breeding habitats for the malaria vector Anopheles darlingi Root.

Densities of adult female An. darlingi were recorded in the Upper‐Marowijne region of Suriname, in a focus of malaria along the Marowijne River. Peaks in biting densities correlated well with periods of (i) high water level in the long rainy season, (ii) low water level in the long dry season, and (iii) abundant rainfall in the short rainy season. Critical levels of river‐height and rainfall were defined which could explain most of the monthly fluctuations in malaria parasite incidence observed in this area.
Population dynamics and control of Triatoma infestans
Authors: GORLA DAVID E.
Published: March 2008

Abstract. Analysis of field populations of Triatoma infestans (Hemiptera: Reduviidae), after a 3‐year study, shows that population growth rate is affected by both density‐dependent and density‐independent mortality. Although an equilibrium exists, apparently as a consequence of a density dependent‐mechanism, population density fluctuates throughout the year because of the effect of monthly mean minimum temperature as a density‐independent source of mortality. Simulation studies based on Moran curves shows that high population densities have an approximately constant extinction probability (around 0.20), independently of the season the population starts growing. However, at very low population densities, the extinction probability depends strongly on the season when the population begins to grow. Very low density populations beginning in winter or autumn have the highest extinction probability. The outcome of the simulation studies coincides with results observed in field populations affected by insecticide application at different seasons.
Responses of female New World screwworm flies, Cochliomyia hominivorax, to swormlure‐4 in the laboratory
Authors: WARNES M. L. , GREEN C. H.
Published: March 2008

Abstract. The behaviour of 4‐day‐old virgin female New World screwworm flies Cochliomyia hominivorax Coquerel was investigated in a wind tunnel using video. Addition of the screwworm attractant swormlure‐4 to the airstream resulted in an increase in the number of take‐offs and in the duration of flight. In the presence of swormlure‐4 the flight speed decreased and the rate of turning increased. Take‐off was significantly orientated upwind during the period when swormlure‐4 was added to the airstream, and significantly orientated downwind in the period after the addition of swormlure‐4. The possible means by which this species finds a point source of odour in the field are discussed and compared with the mechanisms used by other flies.
Studies on vectors of Trypanosoma cruzi in Trinidad, West Indies
Authors: OMAH‐MAHARAJ INDIRA
Published: March 2008

Abstract.Studies on vectors ofTrypanosoma cruziChagas were conducted during 1982‐85 as part of an investigation on the epidemiological status of American Trypanosomiasis in Trinidad, West Indies. A total of 148 reduviid bugs were collected from caves, armadillo nests and at light traps, comprising four sylvatic species and totalling 120Panstrongylus geniculatus(Latreille), twoP.rufotuberculatus(Champion), twelveRhodnius pictipesStal and fourteenEratyrus mucronatusStal.

A significantly higher level of infection withT.cruziwas recorded forP. geniculatus(42.5%) compared toR.pictipes(8.3%). The other two bug species were not found to be infected.P.geniculatusseems to be the most important vector in the sylvatic cycle of transmission ofT.cruziin Trinidad.
Enzymes in saliva from four parasitic arthropods
Authors: KERLIN R. L. , HUGHES S.
Published: March 2008

Abstract. Enzyme assays and SDS polyacrylamide gel electrophoresis were carried out on saliva and in some cases homogenates of salivary gland and gut from four parasitic arthropods (the cattle tick, Boophilus microplus (Canestrini); the mosquito, Aedes aegypti (L.); non‐parasitic adult and parasitic larval blowfly of sheep, Lucilia cuprina (Wiedemann); the buffalo fly, Haematobla irritans exigua de Meijere). Saliva from all species showed large differences in the number and molecular weight of components, as judged by electrophoresis. Enzyme profiles, however, showed similar enzyme activities (phosphatase, esterase/ lipase) in saliva from species with dissimilar feeding behaviours. There were obvious differences in the enzyme profiles of saliva and gut tissues from the different species that reflected feeding strategies. These differences were mainly in the type and levels of glycosidase and protease activities. It was concluded that many of the components of saliva from different species had similar functions, although a small number of them may be specifically adapted to the mode of feeding for each parasite.
The susceptibility of the mosquitoes Aedes notoscriptus and Culex annulirostris to infection with dog heartworm Dirofilaria immitis and their vector efficiency
Authors: RUSSELL RICHARD C. , GEARY MERILYN J.
Published: March 2008

Abstract. The mosquitoes Aedes notoscriptus (Skuse) and Culex annulirostris Skuse were fed on a dog infected with Dirofilaria immitis (Leidy) and a blood parasite count of approximately 5000 microfilaria per ml. Cx annulirostris ingested almost 4 times as much blood and almost 4 times as many microfilariae as Ae.notoscriptus (mean 26.0 compared to 6.6). Attrition of the filarial numbers occurred primarily within the midgut during the first 24 h following ingestion and was greater in Cx annulirostris than Ae. notoscriptus. Aedes notoscriptus sustained development of almost 8 times as many third‐stage infective larvae as Cx annulirostris (mean of 3.8 compared to 0.5), and thus had a vector efficiency index of 57.6 compared to 1.9 for Cx annulirostris. In a series of investigations Ae. notoscriptus has now been shown to be an important vector for dog heartworm in southern Australia and may be a significant factor in the apparent burgeoning of the disease.
Host preferences of the phlebotomine sandfly Lutzomyia longipalpis in Amazonian Brazil
Authors: QUINNELL R. J. , DYE C. , SHAW J. J.
Published: March 2008

Abstract. Experiments were undertaken to determine the relative attractiveness of humans, dogs and chickens to Lutzomyia longipalpis, the principal vector of Leishmania chagasi causing American visceral leishmaniasis Field experiments in two villages on Marajo Island, Para State, Brazil, showed that one boy attracted significantly more flies than one dog or chicken, and slightly fewer flies than a group of six chickens. Experiments with laboratory‐bred female flies showed that a significantly greater number of flies engorged on a single human than on either a single dog or chicken, and man‐biting catches demonstrated the willingness of flies to bite in the field. It appears that Lu. longipalpis has catholic feeding habits, the attractiveness of different hosts being largely a function of their relative sizes. These results are discussed with reference to the epidemiology of visceral leishmaniasis in Brazil.
Modelling the effect of feeding‐related mortality on the feeding strategy of tsetse (Diptera: Glossinidae)
Authors: RANDOLPH SARAH E. , WILLIAMS BRIAN G. , ROGERS DAVID J. , CONNOR HILARY
Published: March 2008

Abstract. Free‐living haematophagous insects risk death through host grooming responses or through increased susceptibility to predation whenever they take a bloodmeal. In this paper we investigate the effects of these risks on the feeding strategy of tsetse. A model is presented that allows for death of tsetse by starvation if they do not succeed in feeding within a fixed time (set at 6 days in the first instance) and for mortality specifically associated with feeding. In addition there is background mortality that applies to all flies at all times.

The model is used to compute the individual life‐time fertility (number of female puparia per female) as a function of the probability of obtaining a meal (indicated by field data to be very high, usually > 0.85 per day) and the day on which flies start to search for a meal. We suggest that the feeding strategy that would be selected for is that which allows the maximum reproductive output. The model shows that this strategy involves making no attempts to feed for 3–4 days after the previous meal and then attempting to feed with the greatest possible probability until a meal is obtained. The predicted feeding interval, obtained independently of any trapping data, agrees closely with all previous estimates from field studies using a variety of methods. Preliminary results from a laboratory experiment reveal an increased risk of predation of recently fed as compared with hungry tsetse. The lower the actual feeding mortality the more frequently will flies be able to feed should conditions so demand. It is adaptive, however, for tsetse to delay attempting to feed for as long as they can, which is made possible by the near certainty of locating and feeding on a host within 1 day, using their sophisticated sensory systems.
Acquired immunity to larvae of Amblyomma marmoreum and Ahebraeum by tortoises, guinea‐pigs and guinea‐fowl
Authors: FIELDEN L. J. , RECHAV Y. , BRYSON N. R.
Published: March 2008

Abstract. A study of acquired resistance in guinea‐pigs, guinea‐fowl and tortoises to larvae of the ticks Amblyomma hebraeum Koch and A.marmoreum Koch (Acari: Ixodidae) showed that repeated infestations of the laboratory host resulted in a 29.3–49.4% reduction respectively in weight of engorged larvae. No resistance was induced in guinea‐fowl, the natural host for larvae of both species. A small decline in the mean weight of engorged larvae was observed for both species of ticks after three successive infestations on tortoises. The reduction in weight was more pronounced in A.hebraeum (14.5%) which does not naturally feed on tortoises than for A.marmoreum (8.4%), a common tick on this host. The occurrence of acquired resistance in natural tick host relationships as opposed to unnatural tick host relationships is discussed.
Saliva activated transmission (SAT) of Thogoto virus: relationship with vector potential of different haematophagous arthropods
Authors: JONES LINDA D. , HODGSON ELIZABETH , WILLIAMS TREVOR , HIGGS STEVE , NUTTALL PATRICIA A.
Published: March 2008

Abstract. Tick saliva (or salivary gland extract) potentiates the transmission of Thogoto (THO) virus to uninfected ticks feeding on a non‐viraemic guinea‐pig. This phenomenom has been named saliva activated transmission (SAT). To investigate the potential of different haematophagous arthropods to mediate SAT, guinea‐pigs were infested with uninfected R.appendiculatus Neumann nymphs and inoculated with THO virus and salivary gland extract (SGE) derived from a range of ixodid (metastriate and prostriate) or argasid ticks, or mosquitoes; control guinea‐pigs were inoculated with virus alone. Enhancement of THO virus transmission was observed only when SGE was derived from metastriate ticks. Comparison with the vector potential of these various arthropod species revealed that enhancement of THO virus transmission was specific for ticks which were competent vectors of the virus. The data indicate a correlation between vector competence and the ability of haematophagous arthropods to mediate SAT of THO virus.
Effects of Toxorhynchites moctezuma larval predation on Aedes aegypti populations: experimental evaluation
Authors: TIKASINGH ELISHA S.
Published: March 2008

Abstract. Predatory larvae of the mosquito Toxorhynchites moctezuma were used experimentally to control a standing crop of larvae of the dengue vector mosquito Ae.aegypti. Each week, fifty Ae.aegypti first instar larvae were introduced to each of five water‐filled drums (220 litres) of the type commonly used for domestic water storage in Caribbean dwellings. At the beginning of the fourth week, a certain number (0, 1, 2, 5 or 10) of first instar Tx.moctezuma larvae were introduced to each drum and the daily yield of Ae.aegypti adults from each drum was monitored thereafter. The experiment was repeated three times. With only one or two Tx.moctezuma larvae, predation on Ae.aegypti larvae stopped the output of Ae.aegypti adults for 1 week. Five or ten Tx. moctezuma prevented any Ae.aegypti emergence for up to 16 weeks. Cannibalism among Tx. moctezuma larvae was seldom observed and appeared not to be a hindrance in using this species against Ae.aegypti. Thus Tx.moctezuma is regarded as a good candidate for the biological control of Ae.aegypti by augmentative releases.