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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Detecção e caracterização de hemoprotozoários e ectoparasitas em Nasua nasua e Didelphis spp.

Silva, Maria Regina Lucas da. January 2018 (has links)
Orientador: Lucia Helena O'Dwyer / Resumo: Animais silvestres são considerados reservatórios para uma infinidade de patógenos transmitidos por ectoparasitas, dentre os quais Hepatozoon spp. e piroplasmas; e os ectoparasitas atuam como vetores desses micro-organismos. O presente estudo teve por objetivo investigar a ocorrência de Hepatozoon spp., piroplasmas e ectoparasitas em Nasua nasua e Didelphis spp. da região peri-urbana e urbana dos municípios de Botucatu, Palmital e São Paulo, além de identificar os ectoparasitas e caracterizar morfologicamente e molecularmente os hemoparasitas encontrados. Foram coletados ectoparasitas e amostras de sangue de 69 Didelphis albiventris, 11 Didelphis aurita e 83 N. nasua. Também, foram coletadas amostras de baço e fígado de dois N. nasua e de 25 D. albiventris, para análise histológica. Os carrapatos foram identificados e dissecados para pesquisa de oocistos de Hepatozoon spp. e alguns exemplares tiveram seu DNA extraído para verificar a presença de hemoparasitas. Para identificação dos hemoparasitas foram realizados esfregaços sanguíneos, a PCR, clonagem, e posterior sequenciamento das amostras. Primeiramente, Hepatozoon procyonis foi identificado em N. nasua. Dois carrapatos Amblyomma ovale, coletados em N. nasua, também foram positivos para Hepatozoon spp. Um espécimen foi positivo para H. procyonis e o outro para Hepatozoon sp. próximo de um haplótipo de Hepatozoon americanum. Um piroplasma próximo de Babesia sp. capybara foi detectado em Amblyomma sculptum, também coletado e... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Wild animals are considered reservoirs for several pathogens transmitted by ectoparasites, among which Hepatozoon spp., and piroplasms, and the ectoparasites are the vectors of these microorganisms. The present study aim to investigate the occurrence of Hepatozoon spp., piroplasms and ectoparasites in Nasua nasua and Didelphis spp., from peri-urban and urban regions of Botucatu, Palmital and São Paulo municipalities, besides to identify ectoparasites and characterize morphologically and molecularly the hemoparasites found. For this purpose, were collected ectoparasites and blood samples from 69 Didelphis albiventris, 11 Didelphis aurita e 83 N. nasua. In addition, tissue samples were collected from two N. nasua and 25 D. albiventris for histological analysis. Ticks were identified and dissected to recover oocysts of Hepatozoon spp. Some specimens of ticks had their DNA extracted for identification of hemoparasites. For parasitological diagnosis, blood smears were performed, for subsequent identification and morphometry of the parasites. The molecular diagnosis was performed by PCR or cloning and sequencing. First, we detected Hepatozoon procyonis infecting N. nasua. Amblyomma ovale collected on N. nasua was also infected by H. procyonis and by Hepatozoon sp. closely related to a Hepatozoon americanum haplotype. A piroplasm closely related to de Babesia sp. capybara was detected in Amblyomma sculptum collected also on N. nasua. We detected, for the first time, H. canis infecti... (Complete abstract click electronic access below) / Doutor
142

Ecology of lawbreaking:effects of poaching on legally harvested wolf populations in human-dominated landscapes

Suutarinen, J. (Johanna) 23 April 2019 (has links)
Abstract Illegal killing of wolves (hereinafter ’wolf poaching’) in human-inhabited areas where wolves are also legally harvested is a special case of wildlife crime. This doctoral thesis examines wolf poaching in Finland and Sweden from the ecological perspective. In the first paper, we examined the causes of mortality among collared Finnish wolves and the role of estimated poaching rates on population changes. The second paper related the likelihood of being poached to covariates expressing different dimensions of the wolf conflict at two spatial scales (territory and country level) in Finland. Third paper turns the focus to Sweden, where we examined the disappearances of adult wolves in relation to population size, legal harvest and inbreeding. The first two studies were done in collaboration with the Natural Resources Institute Finland (Luke) and the third with the Scandinavian wolf research project SKANDULV. Poaching outnumbered other causes of death. Most poaching cases were unverified. Other causes of death were legal harvest, traffic and natural mortalities. Both populations had a relatively high number of wolves with unknown fates. Inbreeding was not related to the disappearances of adult wolves in Sweden. Remoteness to human inhabitation and the detectability of the wolves from the forest roads (road crossings by wolves) increased the likelihood of poaching in Finland. Adult wolves suffered high risk of poaching in both populations. Risk was highest in early spring in Finland. Larger population size increased and the number of legally harvested wolves decreased poaching in both countries. Poaching seemed to limit the study populations despite the management efforts that used legal hunting as a tool to increase tolerance towards wolves. / Tiivistelmä Suden ja ihmisen rinnakkainelo johtaa konflikteihin, joiden lievittämiseksi susikantoja rajoitetaan usein luvallisella metsästyksellä. Suteen kohdistuu lisäksi laitonta tappamista eli salametsästystä. Tämä väitöstutkimus selvittää salametsästyksen ekologisia vaikutuksia Suomen ja Ruotsin susipopulaatioihin. Ensimmäisessä osatyössä selvitimme suomalaisten pantasusien kuolinsyitä, arvioimme salametsästyksen voimakkuutta ja sen vaikutuksia populaatiotasolla. Toisessa osatyössä tarkastelimme susikonfliktiin liittyvien ennustetekijöiden vaikutusta laittomasti tapetuksi tulemisen riskiin reviiritasolla ja koko Suomen mittakaavassa. Kaksi ensimmäistä osatyötä tehtiin Luonnonvarakeskuksen (Luke) suurpetotutkimuksessa. Kolmas osatyö tehtiin osana skandinaavista susitutkimushanketta (SKANDULV). Siinä selvitimme populaatiokoon, luvallisen pyynnin ja sukusiittoisuuden vaikutuksia aikuisten susien katoamiseen Ruotsissa. Salametsästys oli susien yleisin kuolinsyy, mutta suurin osa tapauksista jää toteen näyttämättä. Muita kuolinsyitä olivat luvallinen metsästys, liikenne ja luonnolliset kuolinsyyt. Aineistoissa oli runsaasti kohtaloltaan tuntemattomaksi jääneitä yksilöitä. Yksilöiden sukusiittoisuusaste ei ollut yhteydessä susien katoamisiin Ruotsissa. Syrjäinen sijainti ja susien havaittavuus metsätiestöltä lisäsivät laittoman tapon todennäköisyyttä Suomessa. Salametsästysriski oli korkein kevättalvella. Aikuisilla susilla oli huomattavan korkea riski tulla laittomasti tapetuksi. Tutkimuksen perusteella salametsästyksen määrää selittävät erityisesti susipopulaation kulloinenkin koko ja luvalliset pyyntimäärät. Suurempi susikanta lisäsi salametsästystä ja metsästyslupien määrä vähensi sen riskiä. Salametsästys vaikuttaa säädelleen susikantoja siitä huolimatta, että susikonfliktia on pyritty lieventämään luvallisella metsästyksellä.
143

Avalia??o cl?nica, morfol?gica, hematol?gica, bioqu?mica e biomolecular de c?es naturalmente infectados por Ehrlichia canis e Anaplasma platys / Clinical, morphologic, hematological, biochemist and biomolecular evaluation of naturally infects dogs for Ehrlichia canis and Anaplasma platys

Sousa, Val?ria R?gia Franco 20 February 2006 (has links)
Made available in DSpace on 2016-04-28T20:16:32Z (GMT). No. of bitstreams: 1 2006-Valeria Regia Franco Sousa.pdf: 1545960 bytes, checksum: 07990d273ccfe1ac6c38929e5d3d100c (MD5) Previous issue date: 2006-02-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work had for objective to investigate the infection for Ehrlichia canis and Anaplasma platys in the dogs taken care of in the Veterinarian Hospital of the Universidade Federal de Mato Grosso, through the examination of blood smears and of the PCR, analyzing the clinical and laboratories findings. During the period of May of 2004 the July of 2005, 195 dogs with suggestive clinical signs of ehrlichiosis or had contact with the infection had been examined. The canine cyclic thrombocytopenia, caused for the A. platys, provokes reduction of platelets to each 14 days, without provoking severe signs, but when associated to the infection for E. canis the clinical gravity it increases. In the thirteen dogs taken care of with positive PCR for E. canis diagnosised by the PCR it was possible to verify the diversity of signals, with statistical significant predominance of the hemorrhagic riots. Already in the 195 dogs tested for the examination of blood smears it did not have predominance of no clinical signs. The hematologic findings had also been nonspecific, occurring in such a way anemia, leukopenia and thrombocytopenia, how much normality or increase of the cells. The alterations observed in the analysis biochemist had not been exclusive of the groups with infection. In these groups increase of plasma proteins occurred, with hyperglobulinaemia, without, however to have significant difference, despite this finding being frequent in ehrlichiosis. From the analysis of the PCR it was confirmed that the infection for E. canis and A. platys occur in the dogs taken care of in the Veterinarian Hospital of the UFMT, having to be taken writ of prevention, mainly in the control of the vector, since all the ticks found in the examined dogs had been of species Rhipicephalus sanguineus. / Este trabalho teve por objetivo investigar a infec??o por Ehrlichia canis e Anaplasma platys nos c?es atendidos no Hospital Veterin?rio da Universidade Federal de Mato Grosso, atrav?s das t?cnicas de esfrega?o sang??neo e de PCR, analisando os achados cl?nicos e laboratoriais. Durante o per?odo de maio de 2004 a julho de 2005 foram examinados 195 c?es com sinais cl?nicos sugestivos de erlichiose ou com contactantes com a infec??o. A trombocitopenia canina c?clica, causada pelo A. platys, provoca diminui??o das plaquetas a cada 14 dias, sem provocar sinais severos, mas quando associada ? infec??o por E. canis a gravidade cl?nica aumenta. Nos treze c?es atendidos com PCR positiva para E. canis foi poss?vel verificar a diversidade de sinais, com predomin?ncia estatisticamente significativa dos dist?rbios hemorr?gicos. J? nos 195 c?es testados pela t?cnica de esfrega?o sang??neo n?o houve predom?nio de nenhum sinal cl?nico. Os achados hematol?gicos tamb?m foram inespec?ficos, ocorrendo tanto anemia, leucopenia e trombocitopenia, quanto normalidade ou aumento das c?lulas. As altera??es observadas na an?lise bioqu?mica n?o foram exclusivas dos grupos com infec??o. Nestes grupos ocorreu aumento das prote?nas plasm?ticas, com hiperglobulinemia, sem, no entanto haver diferen?a significativa, apesar deste achado ser freq?ente na erliquiose. A partir da an?lise da PCR confirmou-se que a infec??o por E. canis e A. platys ocorre nos c?es atendidos no Hospital Veterin?rio da UFMT, devendo ser tomadas medidas preventivas, principalmente no controle do vetor, j? que todos os carrapatos encontrados nos c?es examinados foram da esp?cie Rhipicephalus sanguineus.
144

Aspectos epidemiol?gicos da Babesia canis vogeli em c?es da Baixada Fluminense, RJ / Aspects of Babesia canis vogeli in dogs from Baixada Fluminense, RJ

VILELA, Joice Aparecida Rezende 30 March 2012 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-05T17:41:38Z No. of bitstreams: 1 2012 - Joice Aparecida Rezende Vilela.pdf: 2330778 bytes, checksum: 444dfb2be034c128fc34d8e5ad64d910 (MD5) / Made available in DSpace on 2017-05-05T17:41:38Z (GMT). No. of bitstreams: 1 2012 - Joice Aparecida Rezende Vilela.pdf: 2330778 bytes, checksum: 444dfb2be034c128fc34d8e5ad64d910 (MD5) Previous issue date: 2012-03-30 / CAPES / The canine babesiosis, is a disease widely distributed in Brazil and worldwide, caused by? protozoa of the genus Babesia?spp. that parasitize erythrocytes and it?s transmitted by ticks? Ixodidae. This study aimed to characterize the epidemiology of canine babesiosis through? questionnaires and serological diagnosis by ELISA, diagnosis of Babesia? spp. infection in? dogs by real?time PCR technique, identify the subspecies of B. canis?by RFLP, characterize? the hematological aspects, diagnosis by direct microscopy, identification of ectoparasites and? diagnosis by real?time PCR, the agent of canine babesiosis in ticks from dogs from rural and? urban areas from Serop?dica city, RJ State. The present study evaluated 311 dogs, 167? (n=53,7%) of rural and 144 (n=46,3%) in urban areas. By ELISA technique, was found 39? dogs (12,54%) serologically positive for Babesia canis, with frequency of seropositivity of? 21,56% ???(n=36/167) in dogs of rural area and 2,08% (n=3/144) in dogs from urban area, and? therefore the rural area, the highest seropositivity (p<0,0001). The variables associated with? seropositivity were: area of residence of the dog, breed, age, presence of ticks, environment of? dog access, contact with other animals, the animal's habits, condition of cleanliness of the? environment, absence of veterinary care and animal wandering. The profile of the owner and? its management were striking features in parasitism by ticks and consequently the frequency? of seropositivity to the agent. The diagnostic by PCR real??time of blood samples from dogs? showed a frequency of 11,90% (n=37/311). The subspecies identified affecting dogs of this? region was B. canis vogeli. Of the total of 311 dogs evaluated, infestations by ectoparasites? were found in 252 (81,03%) dogs at the time of collection. Of these, 70,64% (n=178/252)? were infested with ticks. In relation to the infestation, Rhipicephalus sanguineus?was found in? 68,54% (n=122/178) of the dogs, Amblyomma cajennense?in 11,80% (n=21/178), A. ovale?in? 3,37% (n=6/178) and A. dubitatum? in 0,56% (n=1/178). Nymphs of R. sanguineus? and? Amblyomma sp. were observed in 13,48% (n=24/178) and 5,62% (n=10/178) of dogs infected? with ticks, respectively. The tick species most common in urban and rural areas was R. sanguineus, which was associated with positivity of B. canis?in dogs by molecular method.? The frequency of ticks positive for B. canis?was 5% (n=12/240). The DNA from B. canis?was? detected in nine R. sanguineus?ticks, an A. cajennense?adult and two nymphs of Amblyomma? sp. The main hematological changes in infected dogs were: anemia, thrombocytopenia and? hemoglobinemia. The study concluded that canine babesiosis caused by B. canis vogeli?occurs? in rural and urban areas from the Serop?dica being of great importance its occurrence in the? cities of the Rio de Janeiro State, which have characteristics similar expansion of urbanization? to rural areas with little distinction between the two areas and points to the importance of? diagnosis and identification of the pathogen and vectors in dogs, in order to know the? epidemiological conditions for the adoption of appropriate preventive measures, because in? addition to affect the animal health, many of these vectors are capable to transmit pathogens? to humans.? / A babesiose canina, patologia de ampla distribui??o no Brasil e no mundo, ? causada por? protozo?rios do g?nero Babesia? spp., que parasitam hem?cias e s?o transmitidos por? carrapatos Ixodidae. O presente trabalho objetivou determinar a epidemiologia da babesiose? canina atrav?s de aplica??o de question?rios e diagn?stico por ELISA, diagn?stico por? microscopia direta, diagn?stico de Babesia canis? por meio da PCR em tempo real,? identifica??o das subesp?cies de B. canis? por meio da RFLP, caracteriza??o das principais? altera??es hematol?gicas, identifica??o dos ectoparasitos e diagn?stico atrav?s da PCR em? tempo real do agente da babesiose canina em carrapatos de c?es do munic?pio de Serop?dica,? Baixada Fluminense ??RJ. No presente estudo foram avaliados 311 c?es, sendo 167 (n=53,7%)? de ?rea rural e 144 (n=46,3%) de ?rea urbana. Atrav?s do teste de ELISA, encontrou?se um? total de 39 c?es (12,54%) sorologicamente positivos para Babesia canis, com frequ?ncia de? 21,56% (n=36/167) nos c?es de ?rea rural e 2,08% (n=3/144) nos c?es de ?rea urbana, sendo,? portanto a ?rea rural, a de maior soropositividade (p<0,0001). As vari?veis que apresentaram? associa??o com a soropositividade foram: ?rea de domic?lio do c?o, defini??o racial, idade,? infesta??o por carrapatos, locais de acesso do c?o, contato com outros animais, h?bito do? animal, ambiente do c?o, aus?ncia de limpeza do ambiente, aus?ncia de assist?ncia? veterin?ria, aus?ncia de abrigo e origem errante. O perfil do propriet?rio e o manejo do c?o? apresentaram caracter?sticas marcantes no parasitismo por carrapatos e consequentemente na? frequ?ncia de soropositividade para o agente. O diagn?stico pela PCR em tempo real de? amostras sangu?neas de c?es revelou uma frequ?ncia de 11,90% (n=37/311). A subesp?cie? identificada acometendo c?es desta regi?o foi B. canis vogeli. Do total de 311 c?es avaliados,? foram observadas infesta??es por ectoparasitos em 252 (81,03%) c?es. Destes, 70,64%? (n=178/252) apresentaram?se infestados por carrapatos. Em rela??o ? infesta??o por? carrapatos, Rhipicephalus sanguineus foi encontrado em 68,54% (n=122/178) dos c?es,? Amblyomma cajennense em 11,80% (n=21/178), A. ovale em 3,37% (n=6/178) e A. dubitatum em 0,56% (n=1/178) dos c?es infestados por carrapatos. Ninfas de R. sanguineus e? Amblyomma sp. foram observadas em 13,48% (n=24/178) e 5,62% (n=10/178) dos c?es? infestados por carrapatos, respectivamente. A esp?cie de carrapato mais frequente nos meios? urbano e rural foi R. sanguineus, que apresentou associa??o com a positividade de B. canis? vogeli?nos c?es pelo m?todo molecular. A frequ?ncia de carrapatos positivos para B. canis foi? de 5% (n=12/240). O DNA de B. canis foi detectado em nove carrapatos adultos de R. sanguineus, em um adulto de A. cajennense? e em duas ninfas de Amblyomma? sp.. As? principais altera??es hematol?gicas nos c?es infectados foram: anemia, hemoglobinemia e? trombocitopenia. O estudo permitiu concluir que a babesiose canina causada por B. canis vogeli?ocorre nas ?reas rurais e urbanas do munic?pio estudado sendo de grande import?ncia a? sua ocorr?ncia nos munic?pios da Baixada Fluminense do Estado do Rio de Janeiro, os quais? apresentam caracter?sticas semelhantes de expans?o da urbaniza??o para o meio rural com? pequena distin??o entre as duas ?reas e aponta para a import?ncia do diagn?stico do pat?geno? e identifica??o de vetores nos c?es, visando o conhecimento das condi??es epidemiol?gicas? para a ado??o de medidas profil?ticas adequadas, pois al?m de afetarem a sanidade animal? muitos destes vetores s?o capazes de veicularem pat?genos transmiss?veis ao homem.??
145

Formação de classes funcionais em cães domésticos (Canis familiaris) / Functional clases formation in domestic dogs (Canis familiaris)

SOUZA, Liane Dahás Jorge de 02 1900 (has links)
Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-05-13T13:53:04Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_FormacaoClassesFuncionais.pdf: 678932 bytes, checksum: 1a685a737e24ef02e89dad6494f11cb0 (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2014-09-12T12:58:43Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_FormacaoClassesFuncionais.pdf: 678932 bytes, checksum: 1a685a737e24ef02e89dad6494f11cb0 (MD5) / Made available in DSpace on 2014-09-12T12:58:43Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_FormacaoClassesFuncionais.pdf: 678932 bytes, checksum: 1a685a737e24ef02e89dad6494f11cb0 (MD5) Previous issue date: 2009 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente estudo investigou a possibilidade de ensinar dois cães domésticos (Canis familiaris) a responderem adequadamente a duas classes de três estímulos (caixas contendo pedaço de alimento quando com função positiva) através de um procedimento de mudanças sucessivas de discriminação simples (MSDS). A coleta de dados foi realizada em uma sala na qual duas, quatro ou seis caixas de madeira eram dispostas lado a lado, em posições fixas. Inicialmente, os sujeitos responderam a dois estímulos por sessão (um positivo[S+] e outro negativo[S-]), até que quatro das seis caixas apareciam com ambas as funções. Na fase seguinte, as quatro caixas foram apresentadas juntas, de maneira que duas caixas de uma classe eram S+ e as outras duas S-. Foram realizadas mudanças de função até que os sujeitos alcançassem o critério de aprendizagem em 11 de 12 sessões. Em seguida os sujeitos foram expostos a uma sessão ao reforçamento de respostas nas duas caixas ainda não utilizadas e depois a um treino de discriminação simples com as seis caixas. Foi realizado um teste consistindo em uma sessão de mudança com quatro caixas, após a qual eram re-inseridas as duas caixas restantes na sala experimental. Com os resultados negativos obtidos nesse teste, foi realizado um treino de MSDS com as seis caixas, após o qual o teste foi refeito. Ambos os sujeitos responderam adequadamente a todas as tentativas. Outros cinco testes foram realizados com as demais caixas, no mesmo formato do primeiro teste. Um sujeito respondeu adequadamente a dois desses cinco testes e o outro a três deles. Discute-se os efeitos da ênfase na discriminação visual e o uso de posições fixas das caixas sobre o desempenho dos sujeitos. / The present study investigated the possibility of teaching two domestic dogs (Canis familiaris) to respond adequately to two classes of three stimuli (boxes with pieces of food when having S+ function) through a procedure of successive changes of simple discrimination (SCSD). Sessions were carried out in a room in which two, four or six wooden boxes were placed side by side. Initially, the subjects responded to two stimuli (a positive [S+] and another negative [S-]) for session, until four of the six boxes appeared with both of the functions. In the following phase, the four boxes were presented together, whith two boxes of a class functioning as S+ and the other two, as S-. Changes were performed until the subjects reached the criteria of learning in 11 out of 12 sessions. After that, the subjects were trained to respond to the two boxes that had not been used before, and then, the training with all six boxes was initiated. The test took place after a session of change with four boxes in which the two remaining boxes had been re-inserted in the experimental room. Having negative results in this test, training of SCSD was conducted with the six boxes, after which the test was remade. Both of the subjects had adequately responded to all the trials. Other five tests were conducted with the others boxes, in the same format of the first test. One of the subjects adequately responded to two of these five tests and the other to three of them. It is argued about the effect of the emphasis in the visual discrimination and the use of fixed positions of the boxes on the performance of the subjects.
146

Description, Taphonomy, and Paleoecology of the Late Pleistocene Peccaries (Artiodactyla: Tayassuidae) from Bat Cave, Pulaski County, Missouri

Woodruff, Aaron L 01 May 2016 (has links)
The late Pleistocene faunal assemblage from Bat Cave, central Ozarks, Missouri provides an opportunity to assess specific aspects of behavior, ecology, and ontogeny of the extinct peccary Platygonus compressus. All identifiable elements referable to this taxon were catalogued and examined, and a minimum number of individuals of 70 was determined for the sample. The presence of distinct, non-overlapping age groups suggests that P. compressus utilized Bat Cave on a seasonal basis. A predator-prey relationship with Canis dirus, the second most abundant vertebrate from the Bat Cave site, is also described in this study. Damage patterns suggest that the feeding patterns of C. dirus at Bat Cave were consistent with its extant relative, and that these predators would periodically enter the cave to hunt and/or scavenge peccaries. Overall, the fossil material from Bat Cave is virtually unweathered and represents one of the most extensive and well-preserved late Pleistocene faunas from the Ozarks.
147

Validation of a Noninvasive Technique for the Assessment of Physiological Stress in Coyotes (Canis latrans)

Stevenson, Erika T. 01 May 2015 (has links)
Quantifying physiological stress may aid in a better understanding of how animals survive various environmental conditions. One noninvasive technique for assessing physiological stress in animals is to extract steroid hormones from fecal samples. This technique has the potential to aid in wildlife conservation by providing a better understanding of behavior and welfare for a variety of species. The objectives of the study were to (1) determine responses in plasma and fecal steroid hormone concentrations for coyotes (Canis latrans), (2) determine which steroid hormone (cortisol or corticosterone) was better for examining physiological stress responses for coyotes, and (3) determine the amount of time steroid hormone metabolites can be found in coyote scats during 2 different seasons. We first conducted an adrenocorticotropic hormone (ACTH) challenge in 16 coyotes and examined both plasma and fecal steroid hormone concentrations. An ACTH challenge is when there is an externally derived hormone (ACTH) injected into a subjects blood stream, which causes an increase in the subject’s circulating steroid hormones associated with physiological stress. We injected 16 treatment animals with ACTH and 16 control animals with a saline solution. We collected blood and fecal samples pre- and post-injection to measure steroid hormone concentrations. Radioimmunoassay, a laboratory method used to measure substances, was used to measure concentrations of steroid hormones in coyote blood and feces. To evaluate if steroid hormone concentrations remained in feces for an extended period of time we collected samples from 6 captive coyotes and left the samples in natural environmental conditions for 13 days. Each day a sub-sample was collected, and hormones were extracted and run through radioimmunoassay. We found increased steroid hormone concentrations after an ACTH challenge in both blood and feces, validating the use of fecal steroid hormone concentrations as a tool to measure physiological stress in coyotes. We also found there were no differences in levels of steroid hormone concentrations over 13 days. Our study provides validation for use of fecal steroid hormone concentrations in coyotes to quantify stress levels and confirms that steroid hormone metabolites are viable up to 13 days post deposition in coyote scat. This noninvasive tool can aid in the evaluation of the abilities of coyotes to adapt and exist in a variety of habitats.
148

Spatial Ecology of Coyotes and Cougars: Understanding the Influence of Multiple Prey on the Spatial Interactions of Two Predators

Mahoney, Peter J. 01 May 2017 (has links)
The extent to which predators regulate prey populations remains a subject of debate. Yet, when predator control is employed as a management strategy, it is often assumed that predators can and do regulate prey populations. From 2011 through 2015, I monitored the demography and space use of coyotes (Canis latrans) and cougars (Puma concolor) on Monroe Mountain in Fishlake National Forest, Utah as part of a larger collaboration investigating the impacts of coyote aerial control on mule deer (Odocoileus hemionus) neonate survival. My primary objective was to assess the impacts of anthropogenic regulation on the respective populations and identify any cascading effects relevant to mule deer management. To meet this objective, I established a monitoring program for both predators by deploying radio-telemetry collars (VHF and GPS) on each, documented predation events, established surveys for small mammals and lagomorphs to monitor primary prey populations during deer parturition (June – August), and collected data on the location and demographic composition of winter-removed coyotes. I analyzed these data primarily in a community-based, animal movement and resource selection framework permitting the integration of data from multiple sources. When evaluating coyote aerial removal as a management strategy, I identified a spatial dependency in the ability to match removals with indices of deer recruitment as Wildlife Services Operations personnel were primarily limited by terrain and tree cover. Thus, matching treatment with deer fawning was highly variable with only a small number of sites where removals were effective. In addition, I found that coyotes selected for sites with the highest densities of lagomorphs while avoiding areas with a high probability of encountering cougars. Coyotes did not select for mule deer fawning sites, although individual coyotes that occupied resource-poor home ranges were more likely to do so. Cougars strongly selected for mule deer high use areas throughout much of the year, only switching to elk (Cervus elaphus) during the cougar harvest season (i.e., winter). Data from cougar kill site investigations match the observed patterns in cougar space use. My results suggest that predator-prey processes are multi-dimensional and dynamic through time, which likely contribute to the lack of resolution regarding the efficacy of predator control and the regulatory potential of predators in general.
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The Behavior and Ecology of Cursorial Predators and Dangerous Prey: Integrating Behavioral Mechanisms with Population-level Patterns in Large Mammal Systems

Tallian, Aimee 01 May 2017 (has links)
Driving into Yellowstone National Park for the first time is a moving experience. Gazing over the sweeping landscapes, seeing a geyser erupt 80 feet into the air, and having your first ‘wildlife encounter’, whether that be a 2 ton bull bison aggressively wallowing on his dirt mound, snorting and kicking up dust, or watching a pack of 6 wolves move through a valley off in the distance, pausing to howl in search of their companions. Yellowstone staff wishes to manage our park in a way that preserves these remarkable experiences. In order to effectively manage this dynamic ecosystem, it is critical to thoroughly understand how different animal and plant species interact with each other and their environment. Wolves were reintroduced to Yellowstone in 1995-1997 and park researchers and managers are still trying to understand how their presence impacts the ecosystem. In Yellowstone, wolves primarily prey on elk; however, predation on bison has started to increase in recent years. We still know little about how wolves hunt bison and what impacts wolves have had on how bison use their environment. The objective of this study was to better understand the behavioral and ecological interactions of wolves and bison, the most dangerous prey for wolves in North America. Since reintroduction, researchers have collected data on how wolves hunt both elk and bison. I used these data to understand 1) the conditions that allow wolves to capture their most dangerous prey, bison, 2) whether wolves have started preying on bison more often as the bison population increased, and 3) whether wolf reintroduction has limited bison use of Yellowstone’s most extreme high-elevation winter range. Finally, I collaborated with ecologists in Scandinavia to determine how wolf predation was affected by a competitor, the brown bear. My study adds to the current body of work addressing the effects of wolf reintroduction in Yellowstone. This research is unique because it focuses on wolf bison interactions, about which little is known in this system. This research also sheds light on the behavioral relationships at play in a special type of predator-prey interaction: predators that hunt dangerous prey
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Surgical Sterilization of Coyotes to Reduce Predation on Pronghorn Fawns

Seidler, Renee 01 May 2009 (has links)
Coyote (Canis latrans) predation accounts for the majority of neonatal pronghorn (Antilocapra americana) mortality in many areas and may influence local population declines. Current techniques used to manage coyote predation on wildlife species generally focus on lethal control methods. However, these methods may be controversial to the general public. Coyote sterilization is an alternative predation control method which is more acceptable to the public and has been shown to be effective in reducing sheep predation. We hypothesized that surgical sterilization of coyotes may increase pronghorn fawn survival; in the same way it reduces coyote predation on domestic sheep. Sterilization reduces the energetic need to provision coyote pups, which may decrease the predation rate on fawns by sterile coyotes. We employed tubal ligation and vasectomy of captured coyotes to maintain pair bonds and territoriality. We monitored pronghorn fawns by radio telemetry for one year pre-treatment and coyotes and pronghorn fawns one year post-treatment. We also examined the effects of sterilization on coyote territorial maintenance and survival. Survival of fawns captured in sterile coyote home ranges was higher than survival of fawns captured in intact home ranges (P = 0.078). We also found that fawn survival was consistently higher in the northern part of the study site (P = 0.081). A severe winter followed by a wet spring in 2007 did not reduce fawn survival and may have increased fawn survival (P = 0.364); however, our sample sizes did not allow us to detect significance in this relationship. Our results also supported the hypothesis that sterilization, while keeping hormonal systems intact, did not change coyote territorial behaviors. Sterile coyote packs were the same size as intact packs (P = 0.554). Sterile and intact coyote packs maintained similar home range sizes in all seasons tested (P ¡Ý 0.556). We found differences between home range and core area overlap of sterile and intact packs in some seasons, but this trend appeared to exist before the coyotes were treated. Residency rates were similar for sterile and intact coyotes (P = 0.406). We recommend coyote sterilization as a tool to boost pronghorn fawn survival in areas where fawn survival is a critical factor in pronghorn population persistence. Because these techniques have been tested under few circumstances, we recommend careful monitoring in future coyote sterilization programs.

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