摘要:

Abstract.We observed thatPlasmodium bergheisporozoite‐infectedAnopheles stephensiwas not impaired in its ability to locate blood on a host. When probing rats, infected mosquitoes took as long as non‐infected mosquitoes to locate blood.Contrary to previous suggestions, infective mosquitoes delivered sporozoites into mineral oil even after extensively probing a vertebrate host. We observed that, in mosquitoes having probed a host, both the mean number of sporozoites ejected over 3min into oil (35.9v.31.7 sporozoites) and the proportion of mosquitoes delivering sporozoites (60% v. 50%) were similar to mosquitoes not having probed.We then developed a model of sporozoite delivery, taking into account observations that sporozoites are clumped in the lumen of the glands as well as upon delivery, and that output is uneven and inconsistent. We conclude that clumping optimizes transmission, if a threshold of infection exists and the mean number of sporozoites per clump is greater than the thresh

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1992.tb00036.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Abstract.The acceptability of dietary allopurinol to German cockroaches,Blattella germanica(L.), was assessed. In diet choice tests between rat chow with or without 0.1% w/w allopurinol there were no significant differences in nymphal development, feeding duration, visits or consumption. The LT50of cockroaches fed a choice of diets was 3 weeks greater (7.88) than those fed non‐choice a 0.1% allopurinol diet. Female cockroaches provided a choice of diets aborted a significantly greater percentage of their oothecae (98.6%) than those fed the untreated diet (1.7%). Choice arena tests of 2% allopurinol in rat chow significantly reduced cockroach populations compared with untreated controls. After 6 weeks, populations were reduced by approximately 50%, and 97% after 14 weeks. These results indicate that allopurinol is acceptable toB.germanicaas a dietary supplement which could be used in baits for cockroach contro

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1992.tb00037.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Abstract.Coloured, odour‐baited, sticky targets, designed to catch the sheep blowflyLucilia sericataMeigen are described and the results of field trials are presented. The number ofL.sericatacaught by the targets was positively related to target surface area and was dependent on target colour. The performance of the coloured targets is described by a model in which catch is related negatively to reflectivity in the 300–450 nm (ultra‐violet/blue) band of the spectrum and positively to the reflectivity in the 450–580nm (blue‐green‐yellow) band. Of theLuciliablowflies caught by the targets, 13–16% wereL.sericataand 72–75% of theL.sericatawere female. The number ofL.sericatacaught appeared to be positively related to the availability of sheep over a relatively localized area and showed a marked decline following insecticidal dipping of sheep. The further development of targets and the implications of the results forL.sericatacontro

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1992.tb00038.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

Abstract.In two heavily infested rural villages of Santiago del Estero, Argentina, where no indoor‐spraying with residual insecticides had ever been carried out by official control services, we studied the influence of roof and wall structure, domestic use of insecticide, family size and the number of domestic dogs, on the domiciliary density ofTriatoma infestans(Klug). Bug density was significantly associated with (1) the interaction between insecticide use and type of roof, (2) the structure of indoor walls, (3) the number of dogs sharing sleeping areas of people (room‐mate dogs), and (4) the number of people plus room‐mate dogs, but not with just the number of people resident in the house.The interaction between insecticide use and a roof made of ‘simbol’, a locally available grass (Pennisetumsp.), also reflected a younger age structure of domestic bug populations. In infested houses, the density of bugs infected withTrypanosoma cruziChagas was significantly correlated with overall bug density. Our data suggest that the application of environmental management measures by the affected people, such as plastering of walls and modification of roofs, coupled with keeping dogs away from bedrooms and application of insecticides, should limit the domestic population density ofT.infestansand thus reduce the transmission ofT.cruzi

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1992.tb00039.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1992.tb00040.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1992.tb00041.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0269-283X    

DOI:10.1111/j.1365-2915.1992.tb00042.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY