Highlights of Veterinary

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Highlights of Veterinary

Avian influenza (H5N2) and insect vectors(Wilson, D. D. , Schmidtmann, E. T. , Richard, R. D. , Lehman, R. D. 1986 ‘Arbovirus research in Australia’)Percent adult insect pools positive for avian influenza virus,Pennsylvania outbreak 1983/4 (number tested)Musca domesticaOphyra (Hydrotaea) aenescensAlphitobius diaperinusCoproica hirtulaNov ’83-Jan’8415% (20)57% (7)Jan - Feb ’8442% (52)31% (16)3% (34)39% (18)Other species of interest tested without detection include Fanniacannicularis and F. femoralis, Dermestes maculatus and Carcinops spBean et al. (1985) J. Virol. 54:151 also reported isolation of H5N2 from‘flies collected in chicken houses’.Avian influenza and insect vectorsWilson, D. D. , Schmidtmann, E. T. , Richard, R. D. , Lehman, R. D. 1986‘Arbovirus research in Australia’)Species of larvae (number of pools) tested include:No. pools testedNo. positiveM. domestica, 23 0(Pupa) 1 0(Egg) 1 0O. aenescens, 12 0A. diaperinus 22 0D. maculatus 26 1F. cannicularis 3 0Tenebrio molitor 3 0Carcinops sp 3 0Veterinary cases 2006 (to Nov 14 2006)(CDC ArboNET)West Nile VirusPositive 2006Historical reports1500010000Number of confirmed equine cases of WestNile Virus by year (source data APHIS2006)WNV – vector studies• Ceratopogonids could play a role in maintaining enzootic cycles inbirds and as bridging vectors from birds to mamals in Louisiana(Sabio,, Mackay, Roy and Foil 2006, J Med Entomol 43:1020:1020)• WNV from unengorged louse fly – possible role of hippoboscidsin enzootic transmission? (Farajollahiet al. . 2005 J Am Mosq Cont Assoc 21: : 474).• Blood meal studies suggested Cx salinarius as an important bridgevector in NE USA, Cx restuans, Cx pipiens more important inenzootic bird cycles(Molaiet al. 2006 Emerg Inf Dis 12:468 )500001999 2000 2001 2002 2003 2004 2005 2006• Ae triseriatus could be important in the maintenance of enzooticcycles in small mammals in the midwest(Erickson et al. 2006 J Med Entomol 43:966)


Global warming and arbovirusspreadBluetongue and African Horse Sickness to 2002(Tatem, et al. 2003Vet Microbiol 97 13–29)• Potential expansion of the range of arbovirus vectors with globalwarming and of the viruses they carry has received muchattention• Gould et al. . (2006) from their review of potential arbovirusemergence and implications for the United Kingdom concludedthat climate change is probably the most important requirementfor the emergence of a range of arthropod-borne diseases(Gould, Higgs, Buckley, Gritsun 2006 Emerg Inf Dis 12, , 549)■ Before 1998 – sporadic outbreaks south and east of Europe■ Since 1998 – more serious and widespread incursions– (Greece, Spain, Portugal, France, Bulgaria and the Balkan States)– Blamed for death of 800,000 sheep■ 2006 – The Netherlands, Belgium, Germany (Poland).Blue tongue vectors in Europe• Before 2002 – outbreaks linked to incursions of Culicodes immicolafrom North Africa• More recently – bluetongue in areas where C. immicola does not occur• 2005– C. obseletus implicated as vector in central italy(De Liberato et al. Vet Rec 2005 156: 301)• October 2006 – C. dewulfi (obseletus group) implicated as vector inEuropean outbreaks (R.Meisswinkel, OIE press release)• C. dewulfi adaptability to European weather provides the potential forbluetongue to become endemic and expand geographicallyGlobal warming extending vector range and enablingexposure of potential new vectors?Vesicular stomatitis• 2006 – one outbreak in Wyoming• Lysyk (2006) profiled seasonal abundanceand species composition of Culicoides faunaat cattle facilities in Southern Alberta (Lysyk2006 J Med Entomol 43: 840)• Reference point for changes from globalwarmingVesicular stomatitis• C. sonorensis successfully transmitted VSV to guinea pigs and cattle• Although seroconversion occurred clinical signs were not observed• C. sonorensis fed on exposed animals did not become infected• Implications for epidemiology and trade restriction(Perez de Leon and Tabachnik 2006 J Med Entomol 43: 232; Perez de Leon, O’Toole andTabachnik 2006 J Med Entomol 43: 586)Prevention of fly and mosquito spread oncommercial aircraft▬ Horizontal and vertical air curtains directed at 45° with airflow of4m/s excluded 95%-99% of mosquitoes and 95%-100% of houseflies▬ Indications that at least as effective and probably better thanchemical disinsection.(Carlson, Hogsette, Kline, Geden, Vandermeer (2006) J Econ Entomol 99: 182)


Host ranges of filth fly parasitoids from Florida,Eurasia, Morocco and BrazilM. domesticaS. calcitransH. irritansH. aenescensS. bullataMuscidifuraxSpalangiaraptorcameroniFloridaRussiaKahazakstan++++++++++++(Geden,, Moon and Butler 2006 Environmental Entomology 35:405)FloridaRussiaK’stan+++++++++++++S.endiusFloridaRussiaK’stan++++++++++++S.S.DirhiusnigroaeneageminahimalyanusRussiaK’stan++++++++++++Brazil+++++++++++++Morocco+++++++++++Geographic strain differences small although Florida M. raptor betterthan Eurasian strainsFungal entomopathogensBeauvaria bassiana and Metarizium anisopliae• Alpitobius diaperinus▬ 99 isolates of M. anisopliae and B. bassiana screened in Brazilian studies▬ Beauveria strain isolated from A. diaperinus was most effective▬ High level of sporulation on culture media(Rohde et al. 2006 Neotrop Entomol 35, 231)• Rhipicephalus microplus▬ 50 strains of B. bassiana screened▬ Ticks from same locality showed low geneticvariation (RAPID) but often significant variability inpathogenicity(Fernandes et al. 2006 Parasitol Res 98: 324)Metarizium anisopliae• Psoroptes ovis▬ 100% of mites became infected from P. ovis cadavers▬ P. ovis are soft bodied and form dense foci in warm, humidexudative lesions should be good target for fungal biopesticides(Lemkimme et al. 2006 Vet Parasitol 139: 196 )• Bovicola bovis▬ 73% infection in B. bovis confined in 7cm arenas on cattle(Briggs, Colwell and Wall 2006 Vet Parasitol 142: 344)Brevibacillus laterosporosis▬Sardinian strain of entomopathogenic bacterium showed toxicity to M. domesticacomparable with Musca-active Bacillus thuringiensis(Ruiu et al. 2006 Entomol. Exp et Appl. 118: 137)Publications/year120100806040200Peer reviewed articles on Wolbachia toDecember 2006(Floate Kyei-Poku and Cochlin, Biocontrol Science and Technology 16:767)


Tick vaccines• 64P protein, putatively from tick cement may target both exposed andconcealed antigens.▬ 64TRPs effective across tick stages and a number of tick species▬ Blocked transmission of TBEV in a mouse model(Nuttall et al. 2006 Parasite Immunol 28: 155)• Vaccinating cattle with a mixture of two recombinant serine proteaseinhibitors conferred significant protective immunity to R appendiculatus(Imamura et al. 2006 Vaccine 24: 2230)• Identification of exposed antigens stimulating natural immunity identified a19.1kDa specific protein from B. microplus larvae▬ may be useful for a diagnostic Elisa to identify previous exposure ofcattle to B. microplus(Pruett, Untalan and Davey 2006 Vet Parasitol 140: 148)Immune response to other parasites• Although Sarcoptes scabiei mites do not contact host blood they ingesthost immunoglobulins and may be amenable to a concealed antigenimmunisation approach.(Rapp, Morgan and Arlian 2006 J Med Entomol 43: 539)• Infestation with dipteran Oestrus ovis larvae reduces gastrointestinalnematode burden and fecundity in sheep.▬ May be due to non specific activation of eosinophils by O. ovis(Yacob et al. 2006 Vet Parasitol 137: 184.)• Tropomyosin from D. gallinae was a homoloqous to the dust miteallergen Der p 10 and may represent a candidate for a concealedantigen approach to control of poultry red mites(Nisbet et al. Parasite Immunol 2006 28: 401)Arthropods of veterinary importance genomesequencing projectsAnopheles gambiaeAedes aegyptiA. albopictusA. triseriatusAmblyommaamericanumAm. variegatumCulex pipiensCx pipiensquinquefasciatusGlossinia morsitansGenomeGenomeGenomeGenomeESTESTGenomeGenomeGenome and ESTNasonia giraultiN. longicornisGenomes OnLine Database (GOLD): amonitor of genome projects world-wideIxodes scapularisN. vitripenisPediculus humanus(corporus)(Rhodnius prolixusRhipicephalusmicroplus*Lucilia (Phaenicia)cuprinahttp://www.genomesonline.orgGenomeGenomeGenomeGenomeGenomeGenome*Guerrero FD, Nene VM, George JE, Barker SC, Willadsen P (2006). J. Med Entomol 43, 9-16.Applications of RNAi• Silencing a single gene subolesin in Dermacenter variabilis by RNAi producedticks unable to successfully mate and produce viable offspring.▬ Method for development of a sterile acarine technique?(de la Fuente et al. 2006 Biochem Biophys Res Comm 344: 332 )• Silencing of two tick protective antigens of R sanguineous – Rs86 and 4D8(subolesin) by RNAi showed synergistic effect▬ profound effect on tick attachment success, feeding weight andoviposition(de la Fuente et al. 2006 Parasitol Res 99: 108)• Targeting multiple protective antigens may greatly enhance efficacy ofvaccinesEconomic effect• Each engorging R. microplus tick responsible for1.37±0.25 g loss in body weight in Bos taurus cattle,1.18±0.21g in B. taurus x B. indicus cattle.(Jonsson et al. 2006 Vet Parasitol 137: 1-10)• Percent flawless cattle hides increased from 56% in 1998 to 90% in 2003coincident with in increase of parasiticide applications from 6000 to 528000▬ Benefit cost ratio of 4-5:1 plus welfare and calf health impact(Nafstad 2005 Norsk Veterinaertidsskrift 117: 251)• Behavioral response of dairy cattle to stable flies linearly related and cowsmaintained ranks to fly numbers and prevalence of repelling behaviors▬ No consistent effects on milk yield (peak densities = 3-3.5/ leg)(Mullens et al. 2006 Med Vet Entomol 20: 122)Resistance• R. microplus in Texas resistant to coumaphosand diazinon▬ High dose strategy in CTEP unable to eradicate(Miller, Davey and George 2005 J Med Entomol 42: 912)• No reproductive disadvantage associated with pyrethroidor formamidine resistance but reduction of 34.1% inlarval numbers with OP resistant compared to susceptible(Davey, George and Miller 2006 Vet Parasitol 139: 211)• Resistance to tetrachlorvinphos and cyfluththrin in both adults and larvae ofAlphitobius diaperinus (Hamm, Kaufman, Reasor, Rutz, Scott (2006) Pest Man Sci 62: 673)


‘Ethical livestock production’ andveterinary entomology• Animal welfare▬ Greatly increased sensitivity in population at large(Party for Animals in Dutch parliament)▬ Community expectation that animals will be maintained in acomfortable and stress free environment▬ Implications for veterinary entomology in production andcompanion animalsAnimal welfare: the mulesingdebate in AustraliaMulesing:▬ ‘a facelift at the other end’▬ keystone procedure blowfly myiasis IPM programsin Australia over many years▬ Targeted by PETAVeterinary entomologists▬ Highlighted the importance of veterinary entomology inanimal welfare context▬ Involved in mulesing discussions▬ New research approaches▬ Welfare will become increasingly important aspect ofveterinary entomology research and extensionWorld Harmonisation of guidelines for testingectoparasiticides(World Association for Advancement of Veterinary Parasitology)Volume 136, Issue 1, Pages 1-66Biting and nuisance flies on ruminantsP.A. Holdsworth, J. Vercruysse, S. Rehbein, R.J. Peter, C. De Bruin, T. Letonja and P. GreenMyiasisP.A. Holdsworth, J. Vercruysse, S. Rehbein, R.J. Peter, C. De Bruin, T. Letonja and P. GreenTicksP.A. Holdsworth, D. Kemp, P. Green, R.J. Peter, C. De Bruin, N.N. Jonsson, T. Letonja, S. S.Rehbein and J. VercruysseLice and kedsP.A. Holdsworth, J. Vercruysse, S. Rehbein, R.J. Peter, T. Letonja and P. GreenMange and itchmitesJ. Vercruysse, S. Rehbein, P.A. Holdsworth, T. Letonja and R.J. Peter(Flea and tick infestation on dogs and catsA.A. Marchiondo, P.A. Holdsworth, P.Green, B.L. Blagburn and D.E JacobsArticle in Press, Corrected Proof )The Oestrid Flies: Biology, Host-ParasiteRelationships, Impact and ManagementD. D. Colwell, M. J. R. Hall and P. J. SchollImportance and Impact of Oestrids R A Roncalli,Phylogeny and Evolution of the Bot Flies T Pape,Molecular Phylogeny and Identification D Otranto and J R StevensLife Cycle Strategies D D ColwellMorphology of Adult Oestridae D M WoodEgg Morphology D D ColwellLarval Morphology D D ColwellPupal Biology and Metamorphosis Behaviour A C NilssenAdult Biology J R AndersonLarval - Host Parasite Relationships C Boulard, E Lello, D Colwell and P DorchiesOestrid Myiasis of Humans J R AndersonManagement and Control of Oestrid Flies P J SchollA Synopsis of the Biology, Hosts, Distribution, Disease D D Colwell, M J R Hall and P J SchollHighlights of VeterinaryEntomology 2006 - Bibliographyhttp://www.dpi.qld.gov.au

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