L'émergence de la résistance des poux aux insecticides neurotoxiques ont favorisé le développement de nouveaux pédiculicides à action « mécanique » à base d’huile. Mais le mécanisme précis d’action de ces produits était mal connu. Dans ce travail, nous nous sommes intéressés aux modes d’action de 5 huiles essentielles pédiculicides et d’une huile minérale, la diméticone également pédiculicide. Dans une première étape, j’ai évalué l’efficacité pédiculicide des huiles essentielles. Seule Eugenia caryophyllata s’est révélée très efficace, Litsea cubeba, a montré une efficacité relative. Dans une deuxième étape, j’ai évalué la résistance des poux à la noyade et à l’anoxie, mécanismes d’action revendiqués pour les produits huileux. Alors que les poux résistent jusque 24 h dans l’eau sans se noyer, ils se noient rapidement et meurent dans la diméticone, en moins de 30 min. Les poux meurent également par noyade lorsqu’ils sont immergés dans les composants biochimiques des huiles étudiées. Les poux résistent à l’anoxie jusque 14 h. Dans une troisième étape, l’activité neurotoxique des principaux composants des huiles a été évaluée sur la blatte, Periplaneta americana, seul modèle disponible pour ce travail. Selon la technique du patch-clamp, aucune activité électrophysiologique n’est décelée aux concentrations habituellement utilisées. Enfin, nous avons étudié le génotypage des poux utilisés. Les poux de Bobigny appartiennent à 3 clades : A, B et E. Le clade E est noté pour la première fois en région parisienne. Les agents pathogènes hébergés par ces poux ont été recherchés et nous notons pour la première fois la présence de Bartonella quintana dans les poux de corps de Bobigny / The emergence of resistance in Pediculus h. capitis, to chemical-based insecticides has result the development of "mechanical" oil-based pediculicides. Despite this interest, little is known on the precise mechanism of action of these products. In the current thesis, we have concentrated on the modes of action of 5 essential oils commonly used as pediculicides as well as one mineral oil, dimeticone. At the first step, the pediculicidal efficacy of essential oils was evaluated by in-vitro bioassay. Among oils examined, only E. caryophyllata has proved to be very effective followed by Litsea cubeba. In the second step, the resistance of head lice to drowning and anoxia was assessed. The lice were resistant up to 24 h in the water without drowning whereas they were quickly drown and died in the dimeticone, in less than 30 min. In addition, the lice were died by drowning during immersion in the pure biochemical components of essential oils. In the same way, the lice were resistant to anoxia up to 14 h in an enclosed box without oxygen. In the third step, the neurotoxic activity of the main components derived from mentioned essential oils were analyzed on the cockroach, Periplaneta americana as the sole model available. According to the patch-clamp technique, no electrophysiological activity was detected using habitual concentrations. Finally, the bacterial flora of mentioned specimens was studied using molecular analysis. Based on our results, Bartonella quintana was detected for the first time in the body lice collected in Bobigny. According to the genotyping results, the lice of Bobigny belong to three clades of A, B and E. The latter is newly reported in the current thesis

This study examined variation in ectoparasite density and grooming behavior of naturally occurring white-tailed deer (Odocoileus virginianus) in southwest Alabama. Stimulus-driven grooming as well as the intraspecific body size and vigilance principles of programmed grooming were tested. During the rut, males had a higher average tick (Ixodidae) density than females and exhibited complete separation of tick parasitism between non-rutting and rutting periods, supporting the vigilance principle. Stimulus-driven grooming was supported, as both fawns and yearlings had significantly higher fly (Hippoboscidae) and combined fly/tick densities than adults, and fawns oral groomed at a significantly higher rate than adults, even in the absence of allogrooming. Programmed and stimulus-driven grooming of deer examined in this study were not mutually exclusive but ectoparasite dependent.

A infestação por larvas de dípteros, conhecida como miíase, é um grande problema na pecuária em todo o mundo e pode causar perdas econômicas severas. A superfamília Oestroidea é um modelo interessante para estudar a evolução de moscas causadoras de miíase devido à diversidade de estratégias de parasitismo entre espécies intimamente relacionadas nessa família. Essas moscas são classificadas pelo seu hábito alimentar como parasitas saprófagos, obrigatórios ou parasitas facultativos. Os parasitas, em particular, podem ser subdivididos pela manifestação clínica/local de infestação como dérmica, nasofaríngea, traumática/ferida e furuncular. Com tal diversidade de estratégias, postula-se que espécies intimamente relacionadas tenham diferenças genéticas que desempenham um papel na formação desses hábitos. Aqui, utilizamos dados de expressão gênica e as sequências codificantes em escala genômica de cinco espécies (Cochliomyia hominivorax, Chrysomya megacephala, Lucilia cuprina, Dermatobia hominis e Oestrus ovis) para encontrar genes que possam estar envolvidos em diferentes estratégias e/ou preferências alimentares. Nós testamos se os 1.287 ortólogos identificados possuiam expressão diferente e restrições evolutivas em diferentes cenários. Ao comparar seus perfis de expressão gênica, encontramos dois genes regulados positivamente; um genes em espécies que causam miíase dérmica envolvido no transporte metabolização de ferro (Ferritina) e outro gene em espécies que causam miíase traumática que responde a níveis reduzidos de oxigênio (anoxia up-regulation-like). Nossa análise evolutiva mostrou um resultado semelhante. Em Ch. hominivorax, encontramos genes diferentes, mas envolvidos nas mesmas funções que podem estar evoluindo sob seleção positiva. Este é o primeiro passo para entender as origens e a evolução da diversidade de estratégias parasitárias em Oestroidea / The infestation by dipterous larvae, known as myiasis, is a major problem in livestock worldwide and can cause severe economic losses. The Oestroidea superfamily is an interesting model to study the evolution of myiasis-causing flies because of the diversity of parasitism strategies among closely-related species in this family. These flies are classified by their feeding habit as saprophagous, obligate parasites or facultative parasites. The parasites in particular can be subdivided into dermal, nasopharyngeal, traumatic/wound and furuncular. With such a diversity of parasitic strategies, we expect that closely-related species have genetic differences that play a role in shaping these habits. Here, we used gene expression and coding sequence data from five species (Cochliomyia hominivorax, Chrysomya megacephala, Lucilia cuprina, Dermatobia hominis and Oestrus ovis) to find genes that may be involved in different parasitic strategies. We tested whether 1,287 orthologs have different expression and evolutionary constrains in different scenarios. By comparing their gene expression profiles, we found two up-regulated genes; one in species causing dermic myiasis that is involved in iron transportation/metabolization (Ferritin), and other in species causing traumatic myiasis that responds to reduced oxygen levels (anoxia up- regulated-like). Our evolutionary analysis showed a similar result. In the Ch. Hominivorax branch, we found different genes, but involved in the same functions that may be evolving under positive selection. This is the first step towards understanding the origins and evolution of the diversity of parasitic strategies in Oestroidea

Made available in DSpace on 2016-04-28T14:56:36Z (GMT). No. of bitstreams: 1 2008 - Heloiza Helena de Oliveira Morelli Amaral.pdf: 1392333 bytes, checksum: e9a8a156b5bb7fbc58a31fe201039311 (MD5) Previous issue date: 2008-11-28 / From October 2005 to October 2007, rodents and marsupials were captured at Pedra Branca State Park, Rio de Janeiro, RJ. This research aimed to characterize the vegetation concerning the study area; to check the existence of a correlation between mesoclimate and microclimate in relation to the presence of parasites and hosts; to identify the dynamics of the hosts and parasites population throughout the seasons and verify the stratification of the small rodents and marsupials fauna as well as the ectoparasitarian fauna. Six spaces of capture were highlighted, in different levels of height. Three types of traps were used, Sherman, Tomahowk and Francesinha, with different baits distributed in five transects. A hundred and sixty mammals were captured, 96 specimens of marsupials and 64 of rodents from the following species: Akodon cursor, Oligoryzomys nigripes, Rattus norvergicus, Rattus rattus, Guerlinguetus ingrami, Sphigurus villosus, Didelphis aurita, Marmosops incanus, Micoureus paraguayanus, Metachirus nudicaudatus, Monodelphis americana and Philander frenatus. It was possible to observe that in hotter (July and August) and drier (December, January and February) months, the number of animals captured is much lower. The vegetation present in the collection areas (in the six levels researched) is composed by secondary vegetation in different stages of regeneration. The areas placed in levels 150, 200, 300 and 400 m can be classified as areas at initial and medium stage of regeneration, while, the areas situated in levels 500 and 600 m the classification is of areas at medium to advanced stage of regeneration. The correlation between the environment (relative humidity, temperature and pluviometric index) and the ectoparasites was only significant to the ticks, showing that, the higher the temperature, the higher is the number of ticks. The dominant species is D. aurita (35%). Three hundred and seventy specimens of ectoparasites were collected: 162 fleas, 105 ticks and 103 lice. The parasites found were: Siphonaptera: Adoratopsylla (Adoratopsylla) antiquorum ronnai, Adoratopsylla (Tritopsylla) intermedia intermedia, Polygenis (Polygenis) occidentalis occidentalis, Polygenis (Polygenis) rimatus, Polygenis (Polygenis) steganus, Polygenis (Neopolygenis) atopus, Ctenocephalidae felis felis, Acari (Ixodidae): Amblyomma geayi, Amblyomma longirostre, Amblyomma scutatum, Amblyomma spp., Ixodes amarali, Ixodes auritulus, Ixodes didelphidis, Ixodes loricatus, Ixodes luciae, Ixodes spp., Phthiraptera: Poliplax spinulosa, Hoplopleura sciuricola, Eutrichophilus minor and Eutrichophilus cercolabes. The siphonapterus obtained the highest prevalence coefficient (28,13%) and the highest abundance index (1,01 flea/host). The phthirapters presented the highest mean intensity of parasitism (17,17 lice/host). The correlation between the numbers of rodents captured and the levels was not significant (rs = 0,23, p = 0,6) and for the marsupials the correlation was negative and also not significant (rs = -0,6, p = 0,2). Polygenis (P.) occidentalis occidentalis was found at the highest frequency (20,8%) among the rodents and in relation to the marsupials, Adoratopsylla (T.) intermedia intermedia was the most frequent (77,7%). E. cercolabes presented the highest frequency (91,5%) among lice; among ticks the highest frequency was of Ixodes loricatus. / No per?odo de outubro de 2005 at? outubro de 2007, foram capturados roedores e marsupiais no Parque Estadual da Pedra Branca, Rio de Janeiro, RJ. Este trabalho objetivou caracterizar a vegeta??o da ?rea de estudo; verificar se existe correla??o entre mesoclima e microclima com rela??o ? presen?a de parasitos e hospedeiros; identificar a din?mica das popula??es de hospedeiros e parasitos ao longo das esta??es do ano e verificar a estratifica??o da fauna de pequenos roedores e marsupiais e da fauna ectoparasit?ria. Foram marcados seis pontos de captura, em diferentes cotas. Utilizou-se tr?s tipos de armadilhas, Sherman. Tomahowk e Francesinha, com diferentes iscas e dispostas em cinco transectos. Capturou-se 160 mam?feros, sendo 96 esp?cimes de marsupiais, das esp?cies: Didelphis aurita, Marmosops incanus, Micoureus paraguayanus, Metachirus nudicaudatus, Monodelphis americana e Philander frenatus, e 64 de roedores, das esp?cies: Akodon cursor, Oligoryzomys nigripes, Rattus norvergicus, Rattus rattus, Guerlinguetus ingrami, Sphigurus villosus,. A vegeta??o presente nas ?reas de coleta (nas seis cotas pesquisadas) ? composta por vegeta??o secund?ria em diferentes est?gios de regenera??o. As ?reas situadas nas cotas 150, 200, 300 e 400 metros podem ser classificadas como ?reas que est?o em est?gio de inicial a m?dio de regenera??o, enquanto, as ?reas situadas nas cotas 500 e 600 metros a classifica??o ? de ?reas em est?gio de m?dio a avan?ado de regenera??o. A correla??o entre o ambiente (umidade relativa do ar, temperatura e ?ndice pluviom?trico) e os ectoparasitas s? foi significativa para os carrapatos, demonstrando que, quanto maior a temperatura, maior ? o n?mero de carrapatos. Observou-se que nos meses de julho e agosto (meses mais secos) e nos meses de dezembro, janeiro e fevereiro (mais quentes) o n?mero de animais capturados ? muito baixo. A esp?cie dominante ? D. aurita (35%). Coletou-se 370 esp?cimes de ectoparasitas, sendo: 162 pulgas, 105 carrapatos e 103 piolhos. Os parasitos encontrados foram: Siphonaptera: Adoratopsylla (Adoratopsylla) antiquorum ronnai, Adoratopsylla (Tritopsylla) intermedia intermedia, Polygenis (Polygenis) occidentalis occidentalis, Polygenis (Polygenis) rimatus, Polygenis (Polygenis) steganus, Polygenis (Neopolygenis) atopus, Ctenocephalidae felis felis; Acari (Ixodidae): Amblyomma geayi, Amblyomma longirostre, Amblyomma scutatum, Amblyomma spp., Ixodes amarali, Ixodes auritulus, Ixodes didelphidis, Ixodes loricatus, Ixodes luciae, Ixodes spp.; Phthiraptera: Poliplax spinulosa, Hoplopleura sciuricola, Eutrichophilus minor e Eutrichophilus cercolabes. As pulgas obtiveram o maior coeficiente de preval?ncia (28,13%) e o maior ?ndice de abund?ncia (1,01 pulga/hospedeiro). Os piolhos apresentaram a maior intensidade m?dia de parasitismo (17,17 piolhos/hospedeiro). A correla??o entre o n?mero de roedores capturados e as cotas n?o foi significativa (rs = 0,23, p = 0,6) e para os marsupiais a correla??o foi negativa e tamb?m n?o significativa (rs = -0,6, p = 0,2). Polygenis (P.) occidentalis occidentalis foi encontrada com a maior freq??ncia (20,8%) entre os roedores e em rela??o aos marsupiais, Adoratopsylla (T.) intermedia intermedia foi a mais freq?ente (77,7%). E. cercolabes apresentou a maior freq??ncia (91,5%) entre os piolhos; entre os carrapatos a maior freq??ncia foi de Ixodes loricatus.

Made available in DSpace on 2016-04-28T20:16:28Z (GMT). No. of bitstreams: 1 2009 - Michelle Goldan de Freitas Tancredi.pdf: 538519 bytes, checksum: ae1613ebf623782066bdba2f97bf53df (MD5) Previous issue date: 2009-02-27 / The objectives of the present study were to evaluate the efficacy and clinical safety of a novel topical 10% fipronil on the control of Ctenocephalides felis felis on dogs and cats and Rhipicephalus sanguineus on dogs; residual efficacy of the fipronil formulation on dog s coat on the control of eggs, larvae and adults of C. felis felis; effect of dispersion of the tested formulation on adults of C. felis felis; and the influence of bathe on the efficacy of the novel formulation against fleas and ticks on dogs. Utilized animals were belong to the the Laboratory of Experimental Chemotherapy in Veterinary Parasitology (LECVP) from the Department of Animal Parasitology of the Institute of Veterinary of the Universidade Federal Rural do Rio de Janeiro or domiciliated ones. Fleas and ticks were gathered from colonies maintained in the LECVP. Methodologies were based on guidelines and the literature. Pulicide efficacy on cats was: 99.4; 100; 100; 95.1; 86.8 and 70% on days +2 +7, +14, +21; +28, +35 e +42, respectively. The efficacy against ticks on dogs was: 100; 100; 95.4; 90.2; 83.4 and 62.6% on days +2 +7, +14, +21; +28 e +35, respectively. Pulicide efficacy on dogs was: 100; 100; 100; 99.5; 99.8 and 91.6% on days +2 +7, +14, +21; +28 e +35, respectively. Those essays demonstrated satisfactory efficacy levels obtained by the formulation and expected residual period against reinfestations. Regarding the influence of shampooing on pulicide activity, the efficacy was 100% on days +3, +7, +14, +21 and +28; 98.4; 95 and 70.6% on days +35, +42 e +49, respectively for the group with only one bathe. The weekly shampooing group presented efficacy of 98.8; 100; 100; 100; 86.9 and 44.2% on days +3, + 7, +14, +21, +28, +35 and +42, respectively. Efficacy against ticks for the group shampooed once was 99.5; 100; 100; 91.8; 91.6; 70.9 and 63.2% on days +3, + 7, +14, +21, +28, +35 and +42, respectively. The weekly shampooing group presented efficacy of 100; 100; 99.1; 81.1; 58.9 e 41.% on days +2 +7, +14, +21; +28 and +35, respectively. Shampooing once did not affect the product s efficacy. Weekly bathes, despite showed satisfactory efficacy, presented shorter residual period. Regarding the in vitro trials to evaluate the residual activity against fleas, the following can be concluded: the adulticide efficacy varied from average to high until day +14; larvicide efficacy was irregular and presented short residual activity; efficacy against eggs was high and presented long residual activity. Regarding the in vitro essays to evaluate speed of kill the formulation was 100% effective within 16h until day +21 and, 24h on days +28 and +35, demonstrating long residual activity. Therefore, the topical 10% fipronil formulation presented, in general, satisfactory efficacy levels and residual activity on C. felis felis on cats and dogs and, R. sanguineus on dogs, comparable to the reference formulation found commercially, besides have presented the desirable clinical safety. / Os objetivos do presente estudo foram avaliar: a efic?cia e seguran?a cl?nica de uma formula??o t?pica de fipronil a 10% no controle de Ctenocephalides felis felis em c?es e gatos e Rhipicephalus sanguineus em c?es; a efic?cia residual de uma nova formula??o em teste de fipronil em pelo de c?es no controle de ovos, larvas e adultos de C. felis felis; o efeito da dispers?o da formula??o teste em pelo de c?es tratados sobre adultos de C. felis felis; e influ?ncia do banho sobre a efic?cia pulicida e carrapaticida em c?es da nova formula??o. Os animais utilizados pertenciam ao Laborat?rio de Quimioterapia Experimental em Parasitologia Veterin?ria (LQEPV), do Departamento de Parasitologia Animal, Instituto de Veterin?ria, da Universidade Federal Rural do Rio de Janeiro ou domiciliados. Pulgas e carrapatos eram provenientes de col?nias mantidas no LQEPV. As metodologias foram baseadas em normas ou literatura. A efic?cia pulicida em gatos foi: 99,4; 100; 100; 95,1; 86,8 e 70% para os dias +2 +7, +14, +21; +28, +35 e +42, respectivamente. A efic?cia carrapaticida em c?es foi de 100; 100; 95,4; 90,2; 83,4; 62,6% para os dias +2 +7, +14, +21; +28 e +35, respectivamente. A efic?cia pulicida em c?es foi: 100; 100; 100; 99,5; 99,8; 91,6% para os dias +2 +7, +14, +21; +28 e +35, respectivamente. Foi constatado que a formula??o em teste obteve satisfat?rios n?veis de efic?cia e esperado per?odo residual contra reinfesta??es. Em rela??o ? influ?ncia do banho na atividade pulicida, a efic?cia foi de 100% para os dias +3, +7, +14, +21 e +28, e 98,4; 95 e 70,6% para os dias 35, +42 e +49, respectivamente no grupo com banho ?nico. Para o grupo com banho semanal, a efic?cia foi de: 98,8; 100; 100; 100; 86,9 e 44,2%, para os dias 3, +7, +14, +21,+28 e +35, respectivamente. A efic?cia carrapaticida no grupo com banho ?nico foi de: 99,5; 100; 100; 91,8; 91,6; 70,9 e 63,2% para os dias +3, + 7, +14, +21, +28, +35 e +42, respectivamente. No grupo banho semanal as efic?cias foram de 100; 100; 99,1; 81,1; 58,9 e 41,3 para os dias +3, +7, +14, +21, +28 e +35, respectivamente. O banho ?nico demonstrou n?o provocar queda da efic?cia do produto. Banhos semanais, apesar de apresentarem efic?cia satisfat?ria, demonstraram menor per?odo residual. Para os experimentos in vitro avaliando atividade residual sobre pulgas pode concluir-se que a efic?cia: adulticida variou de mediana ? alta at? dia +14; a larvicida foi irregular, apresentando curta atividade residual; e a ovicida foi elevada, apresentando longo per?odo residual. Nos ensaios in vitro avaliando a velocidade de morte a formula??o teste foi 100% eficaz em at? 16h at? o dia +21 e 24h nos dias +28 e +35, demonstrando prolongada atividade residual. Portanto, a formula??o teste de aplica??o t?pica de fipronil 10% alcan?ou, em geral, satisfat?rios n?veis de efic?cia e atividade residual sobre C. felis felis em c?es e gatos e R. sanguineus em c?es, compar?veis ? formula??o refer?ncia existente no mercado, al?m de apresentar seguran?a cl?nica desejada.

Orientador: Ariovaldo Pereira da Cruz Neto / Resumo: A perda de habitat é vista como um dos principais efeitos decorrentes das perturbações da paisagem causada pelo homem aos ambientes naturais. Essa gera maior isolamento dos fragmentos e diminui as áreas de contato entre habitat e matriz, com efeitos negativos sobre a biodiversidade. Os efeitos da perda de habitat nos padrões de biodiversidade são geralmente analisados usando dados de distribuição de espécies e / ou abundância relativa. No entanto, eles não podem ser identificados em populações em que esses efeitos ainda não foram refletidos na abundância e incidência de espécies, e não nos informam sobre os mecanismos causais subjacentes às respostas diferenciais de espécies ou populações a essas perturbações. Uma opção para preencher esta lacuna é concentrar-se em quantificar a miríade de processos fisiológicos em que diferentes espécies lidam com ambientes em mudança. Os morcegos apresentam uma grande diversidade morfológica, fisiológica e comportamental, estando presentes em uma diversa variedade de nichos ecológicos, estabelecendo diversas relações críticas para a manutenção dos ecossistemas onde ocorrem. Os morcegos frugívoros estão entre os mais importantes dispersores de sementes do Neotrópico. Juntamente com os morcegos, investigações com seus ectoparasitas específicos são de grande relevância, visto que, os ectoparasitas exercem pressões seletivas importantes sobre a evolução dos seus hospedeiros. Assim, perda de habitat pode trazer importantes mudanças para as popul... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Habitat loss is seen as one of the main effects of man-made landscape disturbances on natural environments. This generates greater isolation of the fragments and reduces the contact areas between habitat and matrix, with negative effects on biodiversity. The effects of habitat loss on biodiversity patterns are generally analyzed using species distribution and / or relative abundance data. However, they cannot be identified in populations where these effects have not yet been reflected in species abundance and incidence, and do not inform us of the causal mechanisms underlying the differential responses of species or populations to these disturbances. One option to bridge this gap is to focus on quantifying the myriad physiological processes in which different species deal with changing environments. Bats have a great morphological, physiological and behavioral diversity, being present in a diverse variety of ecological niches, establishing several critical relationships for the maintenance of the ecosystems where they occur. Fruit bats are among the most important seed dispersers of the Neotropic. Together with bats, investigations with their specific ectoparasites are of great relevance, as ectoparasites exert important selective pressures on their host evolution. Thus, habitat loss can bring about major changes to bat populations and in some biotic interactions such as parasitism. In this context, we use some physiological analysis to (1) evaluate the impacts of habitat los... (Complete abstract click electronic access below) / Mestre

Feral pigs, European wild boars and their crosses are ubiquitous and found in all ecological zones from Florida to California. These introduced animals are recorded in 39 US states and four Canadian provinces. Texas currently has an estimated population of 1-4 million pigs with the potential to exceed 4 million based on suitable habitat estimates. Feral pigs can modify local flora and fauna and cause significant physical damage with their rooting activities. They can also reintroduce parasites and pathogens to previously parasite and pathogen free herds of domestic cattle, horses, sheep, and goats. The two overarching objectives of this research were to determine what role feral pigs have in the maintenance and possible distribution of fleas, lice, and ticks common to the three wildlife districts; and if they serve as bridging hosts for the same (or other) arthropods and their natural hosts. The supporting objectives were to establish host records of fleas, lice, and ticks parasitizing feral pigs; determine species assemblies within each of the three wildlife districts; and to compare species assemblies among the wildlife districts. Feral pigs (564) were taken from June 2008 to March 2011 using box, corral, and panel traps in three wildlife districts. Two hundred fifty six fleas, Pulex porcinus (Jordan and Rothschild), were collected from all gender and age classes of feral pigs at the South Texas Plains wildlife district. No fleas were collected at either the Hill Country or Post Oak Savannah wildlife districts. This is the first report of these fleas on feral pigs. Lice and ticks were collected from all gender and age classes of feral pigs from all sample sites. Only hog lice, Haematopinus suis, were collected at all three sample sites. Seven species of ticks were collected from the three sites: Amblyomma americanum, A. cajennense, A. maculatum, Dermacentor albipictus, D. halli, D. variabilis, and Ixodes scapularis. Amblyomma cajennense was collected only at the South Texas Plains sample site; A. americanum and I. scapularis were collected only at the Hill Country and Post Oak sample sites. This study reports that feral pigs are serving as hosts for one species of flea, one species of lice and seven species of ticks common to Texas.

THESIS ABSTRACT Current control strategies for livestock ectoparasites are limited by problems associated with chemical resistance and residues. Fungal biopesticides could provide an alternative control without these problems. However, a strategic approach is needed to first evaluate the suitability of selected fungal isolates for fungal biopesticide development. Two ectoparasites of significance to cattle and sheep are the cattle tick Rhipicephalus (Boophilus) microplus (Canestrini) and the Australian sheep blowfly Lucilia cuprina (Wiedmann). The fungus Metarhizium anisopliae (Metsch.) Sorokin) was evaluated for its potential to control these livestock ectoparasites. The growth characteristics of 30 isolates of M. anisopliae were investigated. Radial growth measurements were used to identify vigorous isolates that grew well at 30C and were capable of growing at 35C. A qualitative assessment of sporulation capacity further refined the candidate isolate group. A possible nutritive role of oil in the formulation was also investigated. However, there was no clear support for the theory that oil as a formulation additive could boost the germination and growth of the fungal conidia in vitro. Quantal response bioassays were conducted with cattle ticks and sheep blowflies using a range of conidial doses of three different isolates of M. anisopliae and different methods of inoculation. Ticks were either dosed with 2 µl or immersed in the conidial doses. Blowflies were either dosed with 2 µl of the conidial doses or fed conidia mixed with sugar. Probit analyses were carried out on the mortality data to compare the virulence of these isolates to ticks and blowflies and look for indications of different virulence mechanisms employed by M. anisopliae isolates when invading these hosts. One isolate (ARIM16) showed high virulence to both hosts killing 95 % of ticks after two days and 88 (±2) % of blowflies after four days. Strikingly different mortality patterns indicated quite different virulence mechanisms operating when M. anisopliae invades ticks or blowflies. The mortality pattern seen with ticks suggested that the number of conidia adhering per unit area of the cuticle was more important for rapid tick death than the total number of conidia contacting the entire tick surface. Blowflies fed conidia mixed with food died rapidly after an initial lag phase regardless of dose. Microscopic investigations were carried out to resolve the basis of the virulence patterns observed. The spatial and temporal aspects of the invasion of ticks and blowflies by M. anisopliae isolate ARIM16 were investigated with different types of microscopy. The scanning electron microscope and stereo light microscope were used to record surface changes and events and the compound light microscope revealed internal changes. Two distinctly different patterns of invasion were found in ticks and blowflies. Fungal conidia germinated on the surface of ticks then hyphae simultaneously penetrated into the tick body and grew across the tick surface. There was extensive fungal degradation of the tick cuticle with a preference for the outer endocuticle. While large numbers of conidia adhered to the surface of blowflies, no conidia were recorded germinating on external surfaces. One germinating conidium was seen in the entrance to the buccal cavity. Investigations of the fly interior revealed a higher density of hyphal bodies in the haemolymph surrounding the buccal cavity than in haemolymph from regions of the upper thorax. This pattern suggested that fungal invasion of the blowfly is through the buccal cavity. Plentiful extracellular mucilage was seen around the hyphae on ticks, and crystals of calcium oxalate were seen amongst the hyphae on the surface of ticks and in the haemolymph of blowflies killed by M. anisopliae isolate ARIM16. It was considered that cattle ticks are more suited for control with fungal biopesticides than adult blowflies. Three field trials were conducted over twelve months to assess the pathogenicity of M. anisopliae to parasitic stages of R. microplus on dairy heifers under different environmental conditions. Two isolates were selected based on their high optimal growth temperature (30oC), good conidial production characteristics and ability to kill adult engorged ticks in the laboratory in minimum time. Conidia were formulated in an oil emulsion and applied using a motor driven spray unit. Surface temperatures of selected animals were monitored, as were the ambient temperature and relative humidity. Unengorged ticks sampled from each animal immediately after treatment were incubated under laboratory conditions to assess the efficacy of the formulation and application. Egg production by engorged ticks collected in the first 3 days after treatment was monitored. Side counts of standard adult female ticks were conducted daily, before and after treatment to assess the performance of the fungus against all tick stages on the animals. At each trial the formulation caused 100% mortality in unengorged ticks that were removed from cattle and cultured under laboratory conditions. A significant reduction in egg production was recorded for engorged ticks collected in the three days post treatment. In the field, the fungal formulation had an inconsistent effect on ticks, which might be due to the influence of environmental temperature and humidity.

THESIS ABSTRACT Current control strategies for livestock ectoparasites are limited by problems associated with chemical resistance and residues. Fungal biopesticides could provide an alternative control without these problems. However, a strategic approach is needed to first evaluate the suitability of selected fungal isolates for fungal biopesticide development. Two ectoparasites of significance to cattle and sheep are the cattle tick Rhipicephalus (Boophilus) microplus (Canestrini) and the Australian sheep blowfly Lucilia cuprina (Wiedmann). The fungus Metarhizium anisopliae (Metsch.) Sorokin) was evaluated for its potential to control these livestock ectoparasites. The growth characteristics of 30 isolates of M. anisopliae were investigated. Radial growth measurements were used to identify vigorous isolates that grew well at 30C and were capable of growing at 35C. A qualitative assessment of sporulation capacity further refined the candidate isolate group. A possible nutritive role of oil in the formulation was also investigated. However, there was no clear support for the theory that oil as a formulation additive could boost the germination and growth of the fungal conidia in vitro. Quantal response bioassays were conducted with cattle ticks and sheep blowflies using a range of conidial doses of three different isolates of M. anisopliae and different methods of inoculation. Ticks were either dosed with 2 µl or immersed in the conidial doses. Blowflies were either dosed with 2 µl of the conidial doses or fed conidia mixed with sugar. Probit analyses were carried out on the mortality data to compare the virulence of these isolates to ticks and blowflies and look for indications of different virulence mechanisms employed by M. anisopliae isolates when invading these hosts. One isolate (ARIM16) showed high virulence to both hosts killing 95 % of ticks after two days and 88 (±2) % of blowflies after four days. Strikingly different mortality patterns indicated quite different virulence mechanisms operating when M. anisopliae invades ticks or blowflies. The mortality pattern seen with ticks suggested that the number of conidia adhering per unit area of the cuticle was more important for rapid tick death than the total number of conidia contacting the entire tick surface. Blowflies fed conidia mixed with food died rapidly after an initial lag phase regardless of dose. Microscopic investigations were carried out to resolve the basis of the virulence patterns observed. The spatial and temporal aspects of the invasion of ticks and blowflies by M. anisopliae isolate ARIM16 were investigated with different types of microscopy. The scanning electron microscope and stereo light microscope were used to record surface changes and events and the compound light microscope revealed internal changes. Two distinctly different patterns of invasion were found in ticks and blowflies. Fungal conidia germinated on the surface of ticks then hyphae simultaneously penetrated into the tick body and grew across the tick surface. There was extensive fungal degradation of the tick cuticle with a preference for the outer endocuticle. While large numbers of conidia adhered to the surface of blowflies, no conidia were recorded germinating on external surfaces. One germinating conidium was seen in the entrance to the buccal cavity. Investigations of the fly interior revealed a higher density of hyphal bodies in the haemolymph surrounding the buccal cavity than in haemolymph from regions of the upper thorax. This pattern suggested that fungal invasion of the blowfly is through the buccal cavity. Plentiful extracellular mucilage was seen around the hyphae on ticks, and crystals of calcium oxalate were seen amongst the hyphae on the surface of ticks and in the haemolymph of blowflies killed by M. anisopliae isolate ARIM16. It was considered that cattle ticks are more suited for control with fungal biopesticides than adult blowflies. Three field trials were conducted over twelve months to assess the pathogenicity of M. anisopliae to parasitic stages of R. microplus on dairy heifers under different environmental conditions. Two isolates were selected based on their high optimal growth temperature (30oC), good conidial production characteristics and ability to kill adult engorged ticks in the laboratory in minimum time. Conidia were formulated in an oil emulsion and applied using a motor driven spray unit. Surface temperatures of selected animals were monitored, as were the ambient temperature and relative humidity. Unengorged ticks sampled from each animal immediately after treatment were incubated under laboratory conditions to assess the efficacy of the formulation and application. Egg production by engorged ticks collected in the first 3 days after treatment was monitored. Side counts of standard adult female ticks were conducted daily, before and after treatment to assess the performance of the fungus against all tick stages on the animals. At each trial the formulation caused 100% mortality in unengorged ticks that were removed from cattle and cultured under laboratory conditions. A significant reduction in egg production was recorded for engorged ticks collected in the three days post treatment. In the field, the fungal formulation had an inconsistent effect on ticks, which might be due to the influence of environmental temperature and humidity.

Appendix 4.4 removed due to copyright restrictions: Suepaul, R.B., Alley, M.R., Jansen van Rensburg, M., 2010, Salt gland adenitis associated with bacteria in blue penguins (Eudyptula minor) from Hauraki Gulf (Auckland, New Zealand). Journal of Wildlife Diseases, 46(1) : 46-54. / According to the New Zealand Threat Classification, little blue penguin (LBP) (Eudyptula minor) populations are under ‘gradual decline’. Although long-term data are available for some mainland populations, the status of LBP on offshore islands remains largely unknown. Most studies have focussed on breeding success and foraging ecology. However, there is a paucity of data pertaining to diseases and parasites, and the potential effects of these factors on LBP health, reproductive success and survival. To date, the LBP population on Tiritiri Matangi Island, Hauraki Gulf, Auckland, New Zealand, has only been monitored periodically, despite the island being an important habitat for LBP throughout their annual cycle. The overall aim of this study was to examine the relative importance of parasites and disease in relation to key aspects of LBP life-history, including: the annual cycle; reproductive success; energetic demands, immunity; and mortality. During 2006 and 2007, the reproductive success of LBP on Tiritiri Matangi Island was investigated with respect to lay date, nest site attributes, parental quality and ectoparasite loads. A nest treatment experiment was conducted to explore flea (Parapsyllus longicornis) and tick (Ixodes eudyptidis) effects on breeding success. Overall reproductive output was low, estimated at 33.3%, with an average of 0.67 chicks fledged per pair. Lay date and body condition (BC) appeared to be the main drivers of reproductive success, with early breeders fledging significantly more chicks than late breeders. Increased BC improved reproductive success. Although late breeders exhibited higher BC scores, increased chick mortality indicated that late nests face a reproductive trade-off. Treatment did not prove effective in reducing ectoparasite loads and there was no correlation between ectoparasite abundance in the nest and reproductive success. Throughout their geographic distribution, penguins are host to a range of ectoparasites. Using Ixodes eudyptidis ticks as indicators, ectoparasite-host dynamics were investigated over the course of one year, in relation to LBP life stages, body condition (BC) and haematological parameters. To investigate the presence of vector-borne diseases, blood parasite prevalence was determined using molecular techniques and microscopy. Tick load exhibited significant seasonal variation, being highest during periods of increased host availability i.e. moult and breeding. However, these increases in abundance were not associated with body condition or decreased reproductive success of adults. Nonetheless, LBP exhibited seasonal fluctuations in haematological parameters, with decreases in white blood cell concentrations during periods of increased energy demands and high tick loads. Blood parasite prevalence was low (<1%), determined to be Plasmodium sp. infection. No other blood parasites were found. These results indicate that the lifecycle of I. eudyptidis is tightly linked with that of its LBP hosts, and that infested individuals exhibit physiological responses to tick load. LBP exhibit annual fluctuations in mortality and experience periodic mass mortalities. To examine factors associated with mortality, post-mortems were conducted on 32 LBP from the Hauraki Gulf. Additionally, 128 LBP necropsy records were obtained from the National Wildlife Database (HUIA) for the period spanning April 1993-January 2009, and the causes of mortality were reviewed. Starvation and disease accounted for the highest mortality levels, with 65% of deaths attributed to either one or both of these factors. Furthermore, there was a strong association between starvation and parasites. Parasitic disease and diseases of uncertain aetiology were the most common disease types. In all age groups, the likelihood of infectious, non-infectious and disease of unknown aetiology was significantly higher in LBP that harboured one or more parasite species. Results from this study suggest that starvation and disease, including parasites, are significant factors associated with mortality of LBP in New Zealand, as has been found in Australian LBP populations. Parasites and disease are increasingly recognised as a challenge to the conservation of wildlife, and information regarding endemism of pathogens and parasites within populations is vital for determining ecosystem health, and identifying aberrant diseases.