bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of tick control on liveweight gain of cattle in central Zambia
Authors: PEGRAM R. G. , LEMCHE J. , CHIZYUKA H. G. B. , SUTHERST R. W. , FLOYD R. B. , KERR J. D. , McCOSKER P. J.
Published: March 2008

ABSTRACT.Field trials were carried out during 1982‐86 in two different ecotypes in central Zambia to determine the impact of tick control on the liveweight gain (LWG) of cattle. During the first 2 years of the trial a diamidide acaricide (Amitraz) sprayed at weekly intervals caused periodic depression in LWG in young animals. Thereafter a pyrethroid acaricide (cypermethrin) was used. During the 1984‐85 tick season infestations of 50–120 adultAmblyomma variegatumFabricius in untreated animals caused significant reductions in LWG. From the differences in LWG between treated and untreated cattle, the induced loss in LWG was estimated at 46–61 g per engorged femaleA. variegatum.
Estimation of the interval between feeding and capture in peridomestic Glossina tachinoides
Authors: MADUBUNYI L. CHUKA
Published: March 2008

ABSTRACT. From successive 24‐hourly dissections of non‐teneral field‐caught Glossina tachinoides Westwood which had fed on a guinea‐pig in the laboratory, the progressive movement of a bloodmeal through the midgut was monitored and five stages (categories) in the trophic cycle identified. The frequency distribution in these trophic categories of G. tachinoides subsequently caught in the peridomestic agro‐ecosystem at Orie‐Orba near Nsukka by means of the biconical trap revealed that males and females had fed 2.8±0.4 and 2.4±0.4 days respectively preceding their capture.
Resistance and cross‐resistance in guinea‐pigs and rabbits to immature stages of ixodid ticks
Authors: RECHAV Y. , HELLER‐HAUPT A. , VARMA M. G. R.
Published: March 2008

ABSTRACT. Infestation of guinea‐pigs and rabbits with larvae of any one of five species of ticks, Rhipicephalus appendiculatus Neumann, Rhipicephalus evertsi evertsi Neumann, Amblyomma hebrauem Koch, Amblyomma variegatum Fabricius and Ixodes ricinus L., conferred resistance in the animals when exposed to subsequent infestations with the same tick species. Resistance to infestations by other tick species was not observed.
Effectiveness of zooprophylaxis in malaria control: a theoretical inquiry, with a model for mosquito populations with two bloodmeal hosts
Authors: SOTA T. , MOGI M.
Published: March 2008

ABSTRACT. A model for a vector mosquito population with two bloodmeal hosts (man and a domestic animal) was developed to study the influences of domestic animals on the frequency of mosquito bites on man and the endemicity of human malaria. The vector population model, including blood‐feeding success in the adult stage (depending on host density and biting efficiency) and density‐dependent regulation in the larval stage, was combined with the Ross‐Macdonald malaria transmission model.

Model analyses suggested that introduction of domestic animals easily fed upon by mosquitoes increases mosquito density and, in some situations, frequency of mosquito bites on man and the infection rate of malaria through increased success of blood‐feeding. Extinction of malaria was predicted only when an extremely large number of easily accessible (as compared to man) domestic animals are introduced. Limitations in the concept of zooprophylaxis and problems of livestock management in malaria control are discussed.
Laboratory tests of the effects of p‐cresol and 4‐methylcyclohexanol on oviposition by three species of Toxorhynchites mosquitoes
Authors: LINLEY JOHN R.
Published: March 2008

ABSTRACT. Laboratory experiments tested the effects of p‐cresol or 4‐methylcyclohexanol at concentrations of 1,10 and 50 ppm, on oviposition by the mosquitoes Toxorhynchites brevipalpis Theobald, Tx. amboinensis (Doleschall) and Tx. splendens (Wiedemann). A 5+5 ppm mixture of the two chemicals was also tested. All three species laid significantly more eggs in cups containing p‐cresol, whereas only Tx. brevipalpis and Tx. amboinensis responded similarly to 4‐methylcycohexonol and to the mixture of both chemicals. Tx. brevipalpis was, to a relatively limited degree, the most responsive of the three species. Ancillary experiments indicated that the chemicals were acting as attractants, causing more females to fly to treated cups. No stimulant effects were detected either in terms of the proportion of females that initiated oviposition flight (after flying to the cups) or in terms of the number of looping flights executed prior to ejection of an egg.
Efficacy of mosquito nets treated with permethrin in Suriname
Authors: ROZENDAAL J. A. , VOORHAM J. , VANHOOF J. P. M. , OOSTBURG B. F. J.
Published: March 2008

ABSTRACT. In the rain‐forest of Suriname, where malaria is endemic, 95% of the Maroons (who call themselves bush‐negroes) and all Amerindians use mosquito nets made of cotton cloth or, less frequently, nylon or cotton gauze over their hammocks or beds. Bush‐negroes usually wash their nets weekly; Amerindians wash nets at 1–4‐month intervals.

Females of the principal local malaria vector, Anopheles darlingi Root, were seen blood‐feeding through cotton cloth netting (at 22.30‐23.30 hours) on a person sleeping in a hammock; others fed successfully after the net was opened in the morning.

Cotton cloth impregnated with permethrin at a rate of 0.5 g/m2 killed all An. darlingi females exposed for 2 min, but after the material had been washed twice in soapy water the bioassay mortality fell to only 21.4%.

Exit traps on a hut with a single sleeper protected by a permethrin‐impregnated net yielded 185 An. darlingi females (12% blood‐fed) in 74 nights, compared with 276 females (19% blood‐fed) from another hut with a sleeper using an untreated net on the same nights (P< 0.001). No An. dar‐lingi females remained resting alive indoors in these huts during the daytime, and very few were found dead on the floor in the mornings (one treated, seven untreated). The 24 h mortality rate for those collected in exit traps was 58.4% for the test hut and 27.1% for the control hut (P< 0.001).

Bioassays of permethrin‐treated cotton cloth using laboratory‐reared sugar‐fed Culex quinquefasciatus Say females showed that sprayed nets were less effective than nets impregnated by soaking (at equivalent dosages of 0.16‐1.34 g/m2 measured by chemical assay) and confirmed that washing causes severe decline in insecticidal activity.

The feasibility of local mass treatment of mosquito nets is discussed.
Permethrin‐impregnated bednets reduce nuisance arthropods in Gambian houses
Authors: LINDSAY S. W. , SNOW R. W. , ARMSTRONG J. R. M. , GREENWOOD B. M.
Published: March 2008

ABSTRACT. The prevalence of bedbugs (Cimex hemipterus L.), chicken ticks (Argas persicus Oken) and headlice (Pediculus capitis De Geer) was surveyed in a rural area of The Gambia. At the beginning of the study 37.5% of children's beds were infested with bedbugs and 3.9% with chicken ticks, whilst the prevalence rate of pediculosis in children under 10 years old was 28.8%. Both bedbugs and headlice were clustered within compounds. Headlice prevalence increased with hair length and they were more common on girls than boys.

Following this cross‐sectional survey all bednets in the sixteen hamlets were either dipped in permethrin or a placebo. About 4 months later it was found that bedbugs and chicken ticks had disappeared from homes in which the bednets had been impregnated with permethrin. There was no reduction in hamlets with placebo‐treated bednets. The rate of acquiring headlice between the two surveys was reduced by 91.1% in children who slept under insecticide‐treated bednets compared with children with placebo‐treated bednets. There were also significantly fewer day‐flying and crawling insects, except earwigs, in homes of children who slept under insecticide‐treated bednets compared with those with placebo‐treated nets. These additional benefits of permethrin‐treated bednets should contribute to their widespread acceptance and utilization by the community for personal protection.
Effect of temperature on toxicity of three pyrethroids to horn flies
Authors: HINKLE NANCY C. , SHEPPARD D. CRAIG , BONDARI KAINE , BUTLER JERRY F.
Published: March 2008

ABSTRACT. Predictive models describing best‐fit regression equations for per cent mortality of horn flies as a function of temperature were determined for each of three pyrethroid insecticides (fenvalerate, flueythrinate and permethrin) over the temperature range 20–35°C. Susceptible horn flies, Haematobia irritans (L.), were exposed to c. an LC70 dose of each pyrethroid using a residue‐on‐glass method. This technique used confined exposure in chambers with temperatures of 20,25,30 and 35°C. Within this range, mortality was greatest at 25°C with all three insecticides. Estimated temperature‐mortality equations for each pyrethroid revealed different responses of horn flies to each of these insecticides. Horn flies exposed to flucythrinate demonstrated a linear mortality response that varied inversely with temperature. The response to permethrin was described by a quadratic equation, while the response to fenvalerate was best fitted by a cubic equation.
Ctenophthalmus harputus, a new Spalax flea from Turkey
Authors: AKTAŞ METIN
Published: March 2008

ABSTRACT. Ctenophthalmus harputus sp.n. is described from the mole rat Spalax ehrenbergi Nehring collected near Elaziǧ city in eastern Turkey. This new flea species is classified in the Ctenophthalmus (Palaeo‐ctenophthalmus) fissurus Wagner group. A key is given to the six species of Spalax fleas (Siphonaptera: Hystrichopsyllidae, Ctenophthalmus spp.) recorded from Turkey.
The vector competence of Culex annulirostris, Aedes sagax and Aedes alboannulatus for Murray Valley encephalitis virus at different temperatures
Authors: KAY BRIAN H. , FANNING IAN D. , MOTTRAM PIPI
Published: March 2008

ABSTRACT. Culex annulirostris Skuse, colonized from Brisbane. Queensland, and Mildura, Victoria, Australia, were effective vectors of Murray Valley encephalitis virus at 20, 27 and 32–35oC with full extrinsic‐incubation periods of 15, 10 and 4 days respectively. At 20oC, 7–11 days post‐infection, transmission by the Mildura colony (0–20%) was less efficient than the Brisbane colony (30–70%) but both were capable of 75–100% transmission after longer extrinsic incubation periods. Discriminant analysis of body and salivary gland titres showed that these were not satisfactory indicators of transmission. Wild‐caught Aedes sagax (Skuse) and Cx annulirostris from the Murray Valley showed equal competence, but Aedes alboannulatus (Macquart) was a poor vector. The results provide data on rural amplification of Murray Valley encephalitis virus during spring and suggest that further work on the potential of A e. sagax as a natural vector is warranted.
Midgut and salivary gland barriers to La Crosse virus dissemination in mosquitoes of the Aedes triseriatus group
Authors: PAULSON SALLY L. , GRIMSTAD PAUL R. , CRAIG GEORGE B.
Published: March 2008

ABSTRACT. Vector competence for La Crosse virus (LACV) was compared for four species in the Aedes (Protomacleaya) triseriatus group: Ae.triseriatus (Say), Ae.hendersoni Cockerel], Ae.zoosophus Dyar and Knab and Ae.brelandi Zavortink (Diptera: Culicidae). Rates of replication and dissemination of virus in the mosquito hosts were compared and rates of oral transmission of virus to suckling mice were determined. Barriers to virus dissemination which limited the ability of each species to transmit virus were identified.

Ae.zoosophus displayed the highest vector competence for LACV. Both infection and transmission rates were high: 99% and 85% respectively; no significant barriers to LACV were found. Disseminated infection of Ae. triseriatus with LACV was controlled primarily be a midgut escape barrier. When virus was introduced directly into the haemocoel, transmission rates were significantly increased (37% v. 79%). Ae.hendersoni showed high susceptibility to LACV infection but a very low rate of oral transmission (7%). Ae.brelandi was also highly susceptible to infection by LACV and transmitted virus at an intermediate rate (27%). Modulation of vector competence in both Ae.hendersoni and Ae. brelandi resulted from a salivary gland escape barrier.

As these four species of mosquitoes comprise a closely related monophyletic series, their differences of vector competence for LACV provide an excellent model for studying the genetic basis of the barriers involved.
Distribution of phlebotomine sandflies and the rate of their infection with Leishmania promastigotes in the Algarve, Portugal
Authors: SCHREY CHRISTIAN F. , PIRES C. ALVES , MACVEAN D. W.
Published: March 2008

ABSTRACT. Four species of sandflies: Phlebotomus (Larroussius) perniciosus Newstead, Sergentomyia minuta (Rondani), Phlebotomus (Paraphlebotomus) sergenti Parrot and Phlebotomus (Larroussius) ariasi Tonnoir, were collected, by aspiration and light traps, from three dog kennels and an area of high prevalence of human and canine visceral leishmaniasis in the Algarve, Portugal. Midgut infections with leishmanial promastigotes were observed only in P.perniciosus with a minimum infection rate of 5%. The engorgement, gravidity, population dynamics and sex ratios of the sandflies, and the temperature, source and altitude of collection sites were examined. Host preferences were noted for P.perniciosus.
Control of haematophagous flies on equines with permethrin‐impregnated eartags
Authors: PARASHAR B. D. , GUPTA G. P. , RAO K. M.
Published: March 2008

ABSTRACT. The efficacy of 10% (w/w) permethrin impregnated eartags for the control of the haematophagous fly pests Stomoxys calcitrans L., Haematopota dissimilis Meigen and Hippobosca maculata Leach on equines in India was determined. The tags were found to be effective for 1–2 months against S.calcitrans and H. dissimilis but completely ineffective against H. maculata. No tags were lost during the study. Tags can be used as part of an integrated control programme. This is the first reported use of eartags for control of haematophagous flies on horses.
The roles of vision and olfaction in mate location by males of the tsetse fly Glossina morsitans morsitans
Authors: WALL RICHARD
Published: March 2008

ABSTRACT. The roles of visual and/or olfactory stimuli in eliciting mating responses from male Glossina morsitans morsitans Westwood were examined, using a system for automatically recording the number and duration of mating strikes made towards decoys, under controlled conditions. The results confirm that there is no olfactory component of the female sex recognition pheromone sensed by the male antennae, and the attraction of males to females appears to be visual. The absence of male‐male mating strikes was the result of the absence of female sex‐pheromone, rather than the presence of a repellent mating deterrent in the male cuticle. Experiments with coloured, artificial, sex‐pheromone‐dosed, cotton decoys showed that colour had only weak effects on attractiveness and number of encounters with decoys, and that no colour caused significant enhancement of mating responses over those shown to decoy females.
Evaluations of permethrin‐impregnated clothing and three topical repellent formulations of deet against tsetse flies in Zambia
Authors: SHOLDT L. LANCE , SCHRECK CARL E. , MWANGELWA M. I. , NONDO JOSEPH , SIACHINJI VIOLET J.
Published: March 2008

ABSTRACT. Permethrin‐impregnated clothing and three topical repellent formulations of deet (diethyltoluamide) were field tested against natural populations of tsetse flies, mostly Glossina morsitans centralis Machado, in central Zambia. Volunteers wore different combinations of clothing impregnated with permethrin 0.125 mg ai/cm2 and repellents while riding in a vehicle that was driven slowly (4–6 km/h), with the windows and rear door open, through fly‐infested areas. The mean rate of tsetse bites was about twenty per 75 min for unprotected people. The treatment combination of permethrin‐impregnated clothing (blue cotton coveralls) and either of two controlled‐release deet formulations on exposed skin of face and arms provided 91% mean protection, but this was not significantly better (P>0.05) than wearing deet repellent alone (76–87% protection). No significant differences of protection were observed between the three repellent treatments, although the two controlled‐release formulations (intended to be more persistent) were applied at approximately half the dosage of the standard 75% deet. Wearing permethrin‐impregnated coveralls alone provided relatively poor protection (34%) for the untreated and exposed skin of head and hands. However, olive drab mesh jackets treated with permethrin reduced the tsetse biting rate by 75%.
Influence of habitat and temperature on dispersal behaviour of two pteromalid parasitoids of houseflies during an inundative release at a dairy barn
Authors: SMITH LINCOLN , RUTZ DONALD A. , SCOLES GLEN A.
Published: March 2008

ABSTRACT. 1. About 11,000 each of Muscidifurax raptor Girault and Saunders and Urolepis rufipes (Ashmead) were released weekly for 7 weeks at a commercial dairy farm in central New York state, U.S.A. Dispersal behaviour was monitored by parasitism rates of house fly, Musca domestica L., pupae placed in sentinel bags.

2. M.raptor, which was released inside the barn, parasitized fly pupae both inside and outside, and it achieved highest rates of parasitism in indoor straw calf‐bedding and in outdoor manure and silage.

3. U. rufipes, which was released outside the barn, did not attack pupae inside the barn, and its highest rates of parasitism occurred in outdoor manure and silage.

4. M. raptor appeared to be more effective than U. rufipes in parasitizing pupae located at sites where natural fly‐breeding occurred.

5. Interspecific competition did not appear to explain these distribution patterns.

6. There was no significant trend in parasitism by M.raptor as a function of distance from the release station. Furthermore, high rates of parasitism near open doorways and at an outdoor site 30 m away suggests that M.raptor dispersed throughout the barn and its immediate surroundings.

7. Air temperature was positively correlated to flight activity, but not to parasitization activity in natural fly‐breeding substrates.
Population dynamics of Triatoma infestans under natural climatic conditions in the Argentine Chaco
Authors: GORLA D. E. , SCHOFIELD C. J.
Published: March 2008

ABSTRACT. Using experimental chicken houses at a site in central Argentina where the bug Triatoma infestans (Klug) is endemic, nine populations of this vector of Chagas disease were monitored during a 34‐month period. Bug populations with four chickens as hosts were consistently larger than those with two chickens as hosts. Age structure of the bug population followed a similar pattern irrespective of the initial age structure. Egg to adult mortality was consistently around 98.5% and there was no consistent evidence for density‐dependent mortality. There was some evidence for density dependence in fecundity and recruitment rates, but these were heavily constrained by low temperatures during the winter months. Nymphal development rates correlated most strongly with mean minimum temperatures rather than with mean maximum temperatures. We conclude that vector control using insecticides against this species would be most effective at the onset of winter, when recovery of any surviving populations would be inhibited by low temperatures.
Early detection of cattle grub (Hypoderma lineatum and H.bovis) (Diptera, Oestridae) using ELISA
Authors: COLWELL D. D. , BARON R. W.
Published: March 2008

ABSTRACT. .An enzyme‐linked immunosorbent assay (ELISA) to detect cattle grub‐infested animals in the autumn in Alberta has been developed. Antibody to Hypoderma lineatum de Vill. was detectable as early as 6 weeks post‐infestation in artificially infested steers. Peak antibody concentrations preceded the peak in maximum ‘apparent’ grub numbers which occurred between 37 and 43 weeks after infestation. Natural infestations with H. lineatum and H. bovis L., ranging from one to ninety‐two grubs per calf, were readily detected by November and the incidence of false positives in uninfested calves was only 5%. Low level (1–4 grubs) infestations of H. bovis only became detectable in February with peak antibody concentrations occurring at the end of April. Prevalence of cattle grub infestations in southern Alberta was shown to be 37% during this study.
Anti‐mosquito antibodies reduce the susceptibility of Aedes aegypti to arbovirus infection
Authors: RAMASAMY MANTHRIS. , SANDS MICHAEL , KAY BRIAN H. , FANNING IAN D. , LAWRENCE GREGOR W. , RAMASAMY RANJAN
Published: March 2008

ABSTRACT. Aedes aegypti (L.) mosquitoes showed a significant reduction in susceptibility to infection with Ross River virus and Murray Valley encephalitis virus when they were fed on a blood‐virus mixture containing rabbit antibodies to mosquito midgut components. Presence of the antibodies did not demonstrably affect virus titres in infected mosquitoes, nor the transmission of virus from infected mosquitoes to vertebrates.
Facultative blood‐feeding in the crabhole mosquito, Deinocerites cancer
Authors: O'MEARA GEORGE F. , MOOK DAVID H.
Published: March 2008

ABSTRACT. 1. Most of the female crabhole mosquitoes Deinocerites cancer Theobald entering bait traps had undeveloped ovaries.

2. Nearly half of the D.cancer females that were captured in bait traps, but denied blood, were gravid following a 1 week holding period; they developed relatively small egg clutches autogenously (mean=7.4 eggs per gravid female).

3. Although both parous and nulliparous D. cancer females were captured exiting from crabholes, only parous females were attracted to and collected in bait traps.

4. Much larger egg clutches (mean=41.8 eggs per female) were produced anautogenously by mosquitoes that blood‐fed on chickens.

5. All D. cancer females from field collected pupae developed eggs autogenously when allowed to mate and sugar feed in the laboratory. These mosquitoes produced an initial egg clutch with a mean size equivalent to that found in blood‐fed, parous mosquitoes from bait traps.

6. In the field, mating and sugar feeding rather than blood‐feeding seem to stimulate production of the initial egg clutch.

7. D.cancer blood‐feeding appears to be delayed until after the first egg clutch has been laid; some parous crabhole mosquitoes are facultative blood feeders and can produce an egg clutch either with or without a blood meal.
Formulation of pyriproxyfen, a juvenile hormone mimic, for tsetse control
Authors: LANGLEY P. A. , FELTON T. , STAFFORD K. , OOUCHP H.
Published: March 2008

ABSTRACT. A topical dose, in 1 uJ acetone, of 0.02 |xg 2‐[l‐methyl‐2‐(4‐phenoxyphenoxy) ethoxy] pyridine, the juvenile hormone mimic pyriproxyfen (S‐31183, Sumitomo Chemical Co.), caused an adult female tsetse, Glossina morsitans morsitans Westwood, to produce non‐viable offspring for the whole of her life.

Using 14C labelled pyriproxyfen it was determined that as little as 0.001 fig transferred to the in utero larva was sufficient to arrest development in the pupal stage. A formulation in vegetable oil was prepared for treating black cotton cloth targets which caused females to pick up 0.1 p‐g active ingredient (a.i.) by tarsal contact during 1 min of exposure. Males exposed similarly for between 1 and 5 min transferred up to 0.016 |xg a.i. to females if they mated immediately after treatment. Doses as low as 0.01 |xg in 10 |JL1 oil cnT2 on black cotton cloth targets caused females to produce non‐viable offspring for at least two reproductive cycles following exposure. However, a dose of 0.1 u‐g in 10 |xl oil cm‐2 was necessary for an exposed male to cause disruption of the reproductive potential of his mate.

This juvenile hormone mimic has potential to induce sterility via both sexes of tsetse using treated targets or traps under field conditions.
An ivermectin sustained release bolus in cattle: its effects on the tick Ixodes ricinus
Authors: TAYLOR S. M. , KENNY J.
Published: March 2008

ABSTRACT. Five calves were given an intraruminal bolus orally, designed to release ivermectin for 120 days at the rate of 8 mg/day. This is equivalent to a dose of 40 μg/kg/day for a calf expected to weigh 200 kg at the end of the delivery period. Five control calves were given a placebo bolus. On days 7 and 36 after treatment ten nymphs and ten adult female Ixodes ricinus (Linnaeus 1758) were placed in ear bags on the calves. The engorgement rates were monitored for 10 days and subsequent egg production and hatching percentages determined. There were no significant differences between treatment groups for female mortality. However, ivermectin treatment significantly reduced the numbers and weights of engorged females, females laying eggs, and the number of larvae produced on the treated calves was reduced to 3% of that of the control group. The effects on nymphs, although similar, were less consistent than on adults.
Microgeographic distribution of immature Ixodes dammini ticks correlated with that of deer
Authors: WILSON MARK L. , DUCEY ANNE M. , LITWIN THOMAS S. , GAVIN THOMAS A. , SPIELMAN ANDREW
Published: March 2008

ABSTRACT. In order to determine whether the small‐scale distribution of immature Ixodes dammini Spielman et al. corresponds closely to the activity patterns of white‐tailed deer, Odocoileus virginianus (Zimmerman), these relationships were examined in a site on Long Island, New York, U.S.A. We first determined the extent and temporal pattern of adult ticks feeding on deer by examining twenty‐three resident deer tranquilized during September‐December 1985.1, dammini adults infested deer throughout this fall period, most abundantly during October and November. With radio‐telemetry collars attached to deer we determined the relative frequency that they occupied 0.25 ha quadrats of the study site. During the following summer, we examined white‐footed mice, Peromyscus leucopus (Rafmesque), that inhabited these quadrats and removed immature ticks from each. 8975 larval and 163 nymphal /. dammini were removed from 208 mice trapped in forty‐three such quadrats. The frequency of deer using these quadrats was positively correlated with both the number of larval and of nymphal ticks per mouse. These results suggest that risk of I.dammini‐borne zoonotic disease may be decreased by locally reducing deer density in sites that experience intense human activity.
Changes in food selection by workers of the pharaoh's ant, Monomorium pharaonis
Authors: EDWARDS J. P. , ABRAHAM L.
Published: March 2008

ABSTRACT. The results from simple choice test experiments with laboratory and field colonies of pharaoh's ants have revealed two behavioural traits that influence the way in which foraging worker ants respond to foods. Initially, worker ants from laboratory colonies showed a distinct preference for certain foods (e.g. honey and peanut butter). However, when given only these ‘preferred’ foods continuously for several weeks, workers showed a marked preference for other foods when offered a choice. This ‘satiation’ response occurred even though the initial diet was originally highly attractive to foraging workers. In addition, workers show a marked tendency to alternate between carbohydrate foods and protein foods. Thus, workers from colonies fed predominantly on proteins, subsequently showed a marked preference for carbohydrates, and vice versa. The ‘satiation’ and ‘alternation’ responses to foods ensure that colonies receive a diet that is both varied and balanced. In addition, these aspects of feeding behaviour have important consequences for the use of food‐based baits in control measures against Monomorium pharaonis (L.).
Cold resistance in all life stages of two blowfly species (Diptera, Calliphoridae)
Authors: BLOCK W. , ERZINCLIOGLU Y. Z. , WORLAND M. R.
Published: March 2008

ABSTRACT. 1. Freezing was lethal in the eggs, larvae, pupae and adults of the blowflies Calliphora vicina R‐D. and Calliphora vomitoria (L.), but varying degrees of supercooling were found.

2. Cold resistance (as determined by their supercooling capacity) was greatest in eggs (to c.– 25oC), and moderate in other life stages (range ‐7 to – 13oC), which was evident from the distributions of their supercooling points.

3. Water contents of all life stages varied from 63% to 77% of fresh weight; pupae of C. vomitoria contain the smallest proportion of water. No relationship between the amount of body water and supercooling ability was detected.

4. Glucose was the major compound in all life stages of C. vicina, with a maximum concentration of 8.22 μg mg_1 fresh weight in the adults. In addition, five other potential cryoprotectants occurred in concentrations >0.1% of fresh weight. No correlation between solute concentration and supercooling was observed.

5. Both C. vicina and C. vomitoria have sufficient cold hardiness to avoid lethal freezing in sheltered habitats in southern Britain, which may render diapause unnecessary in both species.
Mechanisms of organophosphate and carbamate resistance in Culex quinquefasciatus from Saudi Arabia
Authors: HEMINGWAY J. , CALLAGHAN A. , AMIN A. M.
Published: March 2008

Abstract. Broad spectrum organophosphate resistance in Culex quinquefasciatus Say from Saudi Arabia is inherited as a semi‐dominant characteristic. The resistance has a metabolic basis and confers cross‐resistance against the carbamate propoxur. Organophosphate‐selected strains contain two elevated esterases with the same electrophoretic mobilities as those in resistant Cx quinquefasciatus from Sri Lanka and a range of African locations. Alteration in the sensitivity of acetylcholinesterase to insecticide inhibition does not play a major role in resistance.

There was a significant increase in the amount of Cytochrome P450 in Cx quinquefasciatus lines selected with the pyrethroid permethrin or with the organophosphate pirimiphos‐methyl, but no change in lines selected with five other organophosphates or propoxur, compared to the parental strain, which suggests that oxidases are involved in the P450 mediated resistance to both permethrin and pirimiphos‐methyl.
Preliminary evaluation of four immunological tests for the early diagnosis of Hypoderma tarandi causing hypodermosis in reindeer
Authors: MONFRAY KARINE , I.N.R.A. CHANTAL BOULARD
Published: March 2008

Abstract. 294 serum samples from five Norwegian reindeer herds were examined for antibodies against Hypoderma tarandi L. The first and second larval instars of H. tarandi were tested as antigens in immunodiffusion tests, passive haemagglutination and an Enzyme‐Linked Immunosorbent Assay (ELISA). The latter technique, using first instar antigens, produced the best results. A significant difference (P<0.1%) was observed between the antibody value of naive reindeer bred in France and those from infected Norwegian herds. No correlation was observed between the antibody titre and the number of warbles recovered at necropsy from the 294 Norwegian reindeer.
Artificial immunization of pigeons against Argas polonicus (Ixodoidea, Argasidae)
Authors: DUSBABEK F. , KOHNOVÁ P. , GRUBHOFFER L. , LUKEŠ Š.
Published: March 2008

Abstract. Two subcutaneous injections of salivary gland antigen (SGA) or larval homogenate (LH) at 2‐week intervals induced a resistance in pigeons to Argas (Argas) polonicus Siuda, Hoogstraal, Clifford and Wassef larvae and induced anti‐tick antibodies. The number of larvae rejected after LH immunization was significantly higher compared to SGA immunization but lower than the number of larvae rejected after two natural infestations at 2‐week intervals. The antibody titre reached a peak on day 6 following the first inoculation of LH, and 11–13 days after SGA inoculation. The maximum antibody titre was recorded 6 days after a second challenge for both antigens. The highest antibody titre was reached after the first inoculation with LH but only after the second inoculation with SGA. The sera of pigeons immunized either with SGA or LH cross‐reacted with the other antigen as demonstrated by ELISA. SDS‐PAGE and immunoblot studies demonstrated several differences in the protein profiles of these antigens, the presence of 34 and 35 kdal proteins in SGA and their absence in LH.
Role of prestomal teeth in feeding of the house fly, Musca domestica (Diptera; Muscidae)
Authors: Sz F. KOVACS , MEDVECZKY I. , PAPP L. , GONDAR E.
Published: March 2008

Abstract. Ultrastructural studies of the mouthparts of Musca domestica L. show that the fly's prestomal teeth are more damaging to host tissues than considered previously. When fed on tissue culture or pig cornea, SEM revealed that M.domestica were able to tear and suck up cells. This process occurs so rapidly, and so few cells are involved, that the damage is not perceptible to the naked eye. Except for the prestomal teeth, the mouthparts have few other structures which can inflict the damage observed.
Alighting sites of female Tabanidae (Diptera) at Rekomitjie, Zimbabwe
Authors: PHELPS R. J. , HOLLOWAY M. T. P.
Published: March 2008

Abstract. Twenty‐one species of Tabanidae from four genera were recorded. Where samples were large enough, the preferred alighting sites were determined for the tabanids, and differences in such sites were found for species in three genera. The lower legs of the bait ox were the preferred alighting site for 61.8% of the flies. In the season of peak fly numbers, the bait ox was under stress from the tabanids.
Amplification and analysis of human DNA present in mosquito bloodmeals
Authors: COULSON RICHARD M. R. , CURTIS CHRISTOPHER F. , READY PAUL D. , HILL NIGEL , SMITH DEBORAH F.
Published: March 2008

Abstract. DNA fingerprinting should permit the identification of individual human hosts of haematophagous arthropods, providing epidemi‐ologically useful information, for example, the biting rates on different people and the impact of insecticide‐impregnated bednets.

Investigations reported here demonstrate that it is possible to extract, amplify and fingerprint human DNA from the bloodmeals of individual female Anopheles gambiae mosquitoes kept at 24oC for up to 10–15 h post‐ingestion.
Use of the polymerase chain reaction to identify mosquito species of the Anopheles gambiae complex
Authors: PASKEWITZ S. M. , COLLINS F. H.
Published: March 2008

Abstract. A nonradiometric method has been developed for distinguishing between the sibling species Anopheles gambiae Giles and An.arabiensis Patton, two important Afrotropical vectors of malaria. DNA fragments of species diagnostic length are amplified by polymerase chain reaction (PCR) from a small amount of unknown DNA and three different PCR primers. All three PCR primers are based on ribosomal DNA (rDNA) sequences. A universal plus‐strand primer (A0) is derived from a conserved region at the 3' end of the 28S rDNA coding region. Two species‐specific minus‐strand primers (Aa05 and Ag1 3) are derived from sequences in the intergenic spacers. The Ag13 sequence is approximately 1.3 kb downstream of A0; the Aa05 sequence is about 0.5 kb downstream of A0. When mosquito DNA is amplified in the presence of all three primers, a 1.3 kb fragment is produced if An.gambiae DNA is used as template, and a 0.5 kb fragment is produced if An.arabiensis DNA is used. Amplification of DNA from An. gambiae I An.arabiensis hybrids produces both the 1.3 kb and the 0.5 kb fragments. Neither diagnostic fragment is produced when DNA from other species in the An.gambiae complex is used as template.
Field studies on the potential of butanone, carbon dioxide, honey extract, l‐octen‐3‐ol, L‐lactic acid and phenols as attractants for mosquitoes*
Authors: KLINE D. L. , TAKKEN W. , WOOD J. R. , CARLSON D. A.
Published: March 2008

Abstract. Various combinations of six candidate attractants ‐butanone, carbon dioxide (CO2), honey, octenol, lactic acid and mixed phenols ‐ were tested against natural populations of mosquitoes in Everglades National Park, Florida, U.S.A., using unlighted CDC‐baited traps. With few exceptions, the attractancy of these candidate compounds to mosquitoes, when used alone, was less than that of CO2 alone. The exceptions were that octenol and honey extract alone attracted larger numbers of Coquillettidiaperturbans (Walker). Addition of lactic acid and/or octenol to CO2 increased trap collections of Aedes taeniorhynchus (Wiedemann), Anopheles atropos D. & K., and An. crucians Wiedemann by 1.4–13.8 times. Culex nigripalpus Theobald collections were increased 2.7 times by the addition of lactic acid, while the addition of octenol produced mixed results. Whereas the addition of lactic acid reduced collections of Cx (Melanoconion) spp., the addition of octenol generally increased collections. The opposite happened for Wyeomyia mitchellii (Theobald). For the biting midge, Culicoides furens (Poey), octenol (1.6–23.4X) and phenol (2.7x) alone attracted larger numbers, and lactic acid alone attracted approximately the same numbers as CO2 alone. The combinations octenol + phenol and octenol + 200 ml/min CO2 increased C.furens collections c. 100 times over CO1 alone. The combination of octenol + CO2 increased (1.6x) collections of the tabanid Diachlorus ferrugatus (Fabricius). Butanone appeared to decrease the trap collections of all species when combined with CO2 or octenol + CO2.
Flight activity of insecticide resistant and susceptible Anopheles stephensi mosquitoes in actograph chambers lined with malathion, γ HCH or dieldrin
Authors: ROWLAND MARK
Published: March 2008

Abstract. The activity and resting behaviour of resistant and susceptible Anopheles stephensi Liston were recorded in acoustic actograph chambers lined with residual deposits of malathion, dieldrin or γHCH. In γHCH‐treated flight chambers, SS and RS mosquitoes became active only after picking up lethal doses of insecticide, which explains why few SS and RS mosquitoes survive release into γHCH‐treated experimental huts. Similar results were obtained in flight chambers treated with dieldrin; however, more mosquitoes would be expected to survive dieldrin under field conditions because resistance to this insecticide is greater than to γHCH. Mosquitoes in contact with malathion showed a three‐phase activity pattern: an initial active phase, an inactive phase, and hyper‐activity/convulsions. Initial activity or irritability was especially pronounced in SS and RS but absent in RR mosquitoes. Whether or not irritability would protect RS mosquitoes from malathion would probably depend on the ratio of sprayed to unsprayed surfaces in treated huts.
Cuticular lipid differences between the malaria vector and non‐vector forms of the Anopheles maculatus complex
Authors: KITTAYAPONG P. , CLARK J. M. , EDMAN J. D. , POTTER T. L. , LAVINE B. K. , MARION J. R. , BROOKS M.
Published: March 2008

Abstract. Two chromosomal forms (E and F) of the Anopheles maculatus Theobald complex were distinguished by gas–liquid chromatographic (GC) analysis of cuticular lipids in association with a multivariate principal component analysis. The GC chromatogram obtained from n‐hexane extracts of individual specimens showed no consistent qualitative differences in normalized peak areas between forms. Of the seventeen consistent peaks, five were found to be quantitatively different between forms at a high (99.5–99.95%) level of statistical confidence. Relative ratios of these five quantitatively different GC peaks were used as criteria to distinguish single specimens as either form E or form F.

Chemical structures of the five GC peaks were assigned by both electron impact and chemical ionization gas chromatography/mass spectrometry analysis. The first three peaks, which were always doublets, were partially resolved saturated and mono‐unsaturated free fatty acids; the other two peaks were n‐alkanes. Principal component analysis substantiated that the vector form E has very similar cuticular lipid profiles and is well separated from the non‐vector form F.
Anopheles pharoensis and transmission of Plasmodium falciparum in the Senegal River delta, West Africa
Authors: CARRARA G. C. , PETRARCA V. , NIANG M. , COLUZZI M.
Published: March 2008

Abstract.1.Anopheles pharoensisTheobald was found to be the prevalent man‐biting anopheline mosquito in the central area of the Senegal River delta.

2. Blood‐fed females ofAn.pharoensiswere obtained during September‐December 1987 from mosquito bednets in the village of Souhlloul, near the Boundoum dam, 70 km NE of St Louis.

3. Dried mosquito specimens were identified morphologically and each thorax processed using monoclonal antibody against the circum‐sporozoite protein ofPlasmodium falciparum.

4. FiveAn.pharoensisout of 912 examined were sporozoite positive, while ninety‐eightAn.gambiaeGilessensu latowere all negative. This finding strongly supports the local importance ofAn.pharoensisas a malaria vector.

5. Successful use of pyrethroid‐impregnated bednets against malaria transmission in this situation has helped to achieve more than 90% reduction of malaria prevalence.
Malaria transmission potential of Anopheles mosquitoes in the Mwea‐Tebere irrigation scheme, Kenya
Authors: IJUMBA J. N. , MWANGI R. W. , BEIER J. C.
Published: March 2008

Abstract. 1. Anopheles arabiensis Patton and An.funestus Giles were identified as vectors of Plasmodium falciparum malaria in the Mwea‐Tebere irrigation scheme, Kenya. An.arabiensis was the only member of the An.gambiae complex identified from chromosome characteristics. Other Anopheles species found included An.pharoensis Theobald, An.rufipes Gough and An.coustani Laveran.

Survival rates per gonotrophic cycle for An.arabiensis averaged 0.37 during the short rains (October‐November), 0.49 during the dry season (February) and 0.78 during the long rains (May‐June). Vectorial capacities were correspondingly low due to low survival rates and a high degree of zoophily. The average duration of infective life for P.falciparum was 0.2 days for both An.arabiensis and An.funestus. In contrast, entomological inoculation rates were comparatively high: 6–8 infective bites/man/month.

An.pharoensis averaged 110 bites/man/night during the short rains; 1/999 (0.1%) was positive by ELISA for P.falciparum circumsporozoite antigen, but the ELISA evidence is not conclusive for vector incrimination.

In correspondence with clinical observations, the transmission of P.malariae and P.ovale is unlikely due to the low vector survival rates. The observed anomaly between low vectorial capacities and high entomological inoculation rates demonstrates the importance of accurately estimating vector sporozoite rates to monitor unstable malaria transmission in irrigated areas.
Quantitation of malaria sporozoites transmitted in vitro during salivation by wild Afrotropical Anopheles
Authors: BEIER JOHN C. , ONYANGO FRED K. , KOROS JOSEPH K. , RAMADHAN MUTALIB , OGWANG ROSE , WIRTZ ROBERT A. , KOECH DAVY K. , ROBERTS CLIFFORD R.
Published: March 2008

Abstract. The malaria transmission potential of wild, infective Anopheles from western Kenya was evaluated by determining the number of sporozoites transmitted in vitro by salivation when their mouthparts were inserted into capillary tubes containing either sucrose or blood. With sucrose, 86.6% of 102 infective Anopheles transmitted a geometric mean (GM) of 3.84 sporozoites (range 1–34). With blood, 23.1% of 104 infective Anopheles, tested on the day of collection, transmitted a GM of 2.30 sporozoites (range 1–117). For Anopheles held 5 days postcapture before testing with blood, 53.6% of 56 transmitted a GM of 6.04 sporozoites (range 1–420). Transmitting Anopheles contained significantly more salivary gland sporozoites than non‐transmitters. No significant differences were detected between Anopheles gambiae Giles sensu lato and Anopheles funestus Giles in sporozoite transmission by individuals with sporozoites in their salivary glands.

Sporozoites were detected microscopically in the salivary duct from heads in 80.3% of 117 infective Anopheles (GM=11.2, range 1–71). Sporozoite detection in mosquito heads by ELISA was 25% less efficient than microscopic detection.

Over 98% of the infective Anopheles transmitted less than twenty‐five sporozoites. Transmitted sporozoites represented only about 3% of the total sporozoites in the salivary glands suggesting that sporozoite transmission may be restricted to sporozoites in the salivary duct at the time of feeding. Results are discussed in relation to anti‐sporozoite vaccine development.
Anatomical dissemination of circumsporozoite protein in wild Afrotropical Anopheles affects malaria sporozoite rate determination by ELISA
Authors: BEIER JOHN C. , KOROS JOSEPH K.
Published: March 2008

Abstract. The head, thorax, wings, legs and abdomen of 320 wild‐caught Anopheles gambiae Giles sensu lato and 115 An.funestus Giles were tested by an enzyme‐linked immunosorbent assay (ELISA) for Plasmodium falciparum Welch to determine how anatomical dissemination of circumsporozoite (CS) protein could affect the estimation of malaria sporozoite rates by ELISA. Of fifty‐three Anopheles with CS protein detected in any body part, positive reactions were observed for 58.5% of heads, 67.0% of thoraces, 39.6% of wings, 52.8% of legs and 60.4% of abdomens. Mean absorbance values (range 0–2.00) were highest in thorax samples (1.17), followed by heads (0.80), abdomens (0.67), wings (0.48) and legs (0.46).

Circumsporozoite protein was present in the wings or legs, but not in the head or thorax, in 11.3% (6/53) of the infected Anopheles. The ELISA infection rate of 12.8% (41/320) for An.gambiae would have increased to 14.7% (47/320) by inclusion of six mosquitoes with CS protein in wings or legs alone. The slight overestimation of the proportion of infective mosquitoes due to disseminated CS protein would have little effect on estimates of relative infection rates by ELISA for field‐collected Anopheles, with abdomens removed prior to testing. However, the widespread dissemination of CS protein indicates that sporozoite load estimates by ELISA, for mosquitoes without abdomens, may not provide adequate measurements of the numbers of sporozoites in the salivary glands. Operationally, careful processing of mosquito samples for the determination of infectively rates by ELISA is necessary to prevent the mixing of wings or legs among samples representing individual mosquitoes.
Response of the sandfly Lutzomyia longipalpis to an oviposition pheromone associated with conspecific eggs
Authors: ELNAIEM DIA‐ELDIN A. , WARD RICHARD D.
Published: March 2008

Abstract. Response of female Lutzomyia longipalpis Lutz & Neiva (Diptera: Psychodidae) to an oviposition attractant and/or stimulant associated with conspecific eggs was investigated in the laboratory. Females of two populations laid significantly higher mean number of eggs on sites with 160 eggs already present than on bare control sites. This response was lost when eggs placed on test sites were previously washed in organic solvents and distilled water. Age of eggs placed on test sites, 1–6 days after being laid, did not seem to affect the oviposition response of the females. Comparing effects of different numbers of eggs, positive responses were obtained when 80, 160 or 320 eggs were placed on test sites. No significant differences between mean egg numbers laid on test sites and controls were detected when batches of only 20 or 40 eggs were used.
The louse Trinoton anserinum (Amblycera: Phthiraptera), an intermediate host of Sarconema eurycerca (Filarioidea: Nematoda), a heartworm of swans
Authors: COHEN S. , GREENWOOD M. T. , FOWLER J. A.
Published: March 2008

Abstract. The role of the louse Trinoton anserinum (F) as an intermediate host of Sarconema eurycerca (Wehr) was investigated in swans. 8.3% of healthy swans carried one to twelve lice per bird, dispersed contagiously. Injured and lead‐poisoned swans were more heavily infected.

The mouthparts appear designed to penetrate the hosts' skin; the mandibles are robust and asymmetric, and the maxillae have a serrated intercutting surface. 22% fed exclusively on blood and 33% on both blood and feather. All life‐cycle stages fed upon blood and the barbs and barbules from down feathers; hooklets from contour feathers were only found in adults. 9% of lice were infected with developing nematode larvae in the head, thorax or abdomen.

Lice labelled with Technetium 99 m moved towards the scapulas and the wings. Lice were found to be highly active and were mobile.