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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.
171

Comparação entre eletroacupuntura, cirurgia e cirurgia associada à eletroacupuntura no tratamento da doença do disco intervertebral em cães

Joaquim, Jean Ghilherme Fernandes [UNESP] 18 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-18Bitstream added on 2014-06-13T20:27:19Z : No. of bitstreams: 1 joaquim_jgf_dr_botfmvz.pdf: 1751207 bytes, checksum: 18a2c91a32f8aa041a2876a9d9e2f6d6 (MD5) / Universidade Estadual Paulista (UNESP) / As enfermidades do disco intervertebral são doenças neurológicas freqüentemente encontradas na prática clínica. A compreensão das alterações patológicas associadas à discopatias, ainda não é completa. A opção pelo tratamento clínico ou cirúrgico varia com os achados clínicos e a experiência do médico veterinário. O objetivo deste estudo foi comparar a resposta a diferentes formas de tratamento da discopatia toracolombar e lombar, com base na avaliação do quadro clínico de animais antes e após tratamentos específicos: cirurgia descompressiva, tratamento clínico com eletroacupuntura ou associação de cirurgia e eletroacupuntura. Os 40 pacientes selecionados foram atendidos no período de janeiro de 2003 a julho de 2007, com quadro clínico de discopatia toracolombar. Estes foram então classificados conforme o grau de envolvimento medular (de I a V, com severidade clínica crescente) segundo a classificação de adaptada de Takahashi et al. (1997), Schulz et al. (1998) e Chierichetti e Alvarenga (1999) e divididos em três grupos: G1 (Cirurgia), G2 (Acupuntura) e G3 (Acupuntura e Cirurgia), de acordo com o tipo de tratamento a qual foram submetidos. Para análise estatística utilizou-se o Teste de Goodman para contrastes entre e dentro de populações multinomiais com o nível de significância de 5% (p<0,05). Todos pacientes dos três grupos tinham quadro clínico medular grave (IV ou V), a exceção de um animal grau II do G2. No G1, houve melhora de 40% dos animais tratados, no G2 de 79% e no G3 de 72,7%. Em nenhum animal houve piora clínica. Concluiu-se que o grupo do tratamento com eletroacupuntura foi mais eficiente que o grupo da cirurgia descompressiva tardia para recuperação do quadro neurológico em cães portadores de discopatia. / Intervertebral disc disease is the most commom cause of neurologic disease in small animals. Spinal cord alterations in disc herniation are not completly understood. Treatment options are depending on neurological examination. The aim of this study was to compare the effectiveness of surgery, acupuncture or surgery followed by eletroacupuncture in dogs with disc disease. Dogs with thoracolumbar and lumbar intervertebral disc disease were selected from january 2003 to july 2007. Patients were classified according to a score adapted from Takahashi et al. (1997), Schulz et al. (1998) and Chierichetti and Alvarenga (1999) scale of myelopathy, ranging from I to V with a crescent severerity. Forty animals were treated with surgery (G1), acupuncture (G2) and surgery followed by acupuncture (G3). All of them had a high degree of myelopathy (grade IV-V) except one dog (grade II) in G2 group. Statistical analysis was performed using the Goodman test for comparison of differences between the polinomial populations (p<0,05). We obtained that 40% of the animals improved in G1, 79% in G2 and 72,7% in G3. Electroacupuncture was more effective than late surgery for neurological improvement in dogs with disc disease.
172

Avaliação do espermograma de cães submetidos à administração de cisplatina /

Castro, João Humberto Teotônio de. January 2007 (has links)
Orientador: Carlos Roberto Daleck / Banca: Paulo Henrique Franceschini / Banca: Maria Denise Lopes / Resumo: A correta orientação do Médico Veterinário, aos proprietários de cães, usados com finalidades reprodutivas, submetidas à quimioterapia com cisplatina, é importante na medida que este agente citostático age nas células em constante divisão, podendo ser citotóxicos para as células germinativas testiculares. O objetivo desse trabalho foi avaliar a qualidade espermática através do espermograma de cães que receberam cisplatina em diferentes momentos de análise espermática. A dose utilizada foi de 70 mg/mø, em intervalos de 21 dias, totalizando 4 infusões. Os cães foram divididos em dois grupos de 4 animais cada, sendo que um dos grupos recebeu a quimioterapia e o protocolo de diurese para proteção renal, já o grupo controle não recebeu a cisplatina, estando sujeito apenas aos fatores ambientais. Os resultados obtidos demonstraram que a cisplatina influenciou na qualidade espermática de cães, pois elevou as patologias maiores e totais acima do aceitável para cães aptos a reprodução. Portanto, infere-se que este citostático possa acarretar alterações morfofuncionais nos túbulos seminíferos e conduto epididimário. / Abstract: The correct veterinary's orientation for male dogs' owners used for reproduction goals, undergone cisplatin administration, is important because of this cistostatic act in cell with frequently proliferation, and could to cause germ cell injury. The objections of this experiment was to analysis the sperm quality through dogs' spermogram that received cisplatin's infusions. The dose used was 70 mg/mø in 21 days periods, with 4 infusion in total. The dogs were divided in 2 groups with 4 animal each one. One of the groups received all the diuresys protocol (to protect the kidney) and the citostatic. And the other control group just didn't receive the cisplatin infusion to know the real action of cisplatin effects without environmental stresses. The results show that cisplatin influence at the sperm quality in the dogs, because it elevated the major and total defects above that would be acceptable for competent dog to reproduct. It could deduct that cisplatin cause phisiologic alteration in the testis and epididymis. / Mestre
173

Qualidade microbiológica de rações para cães comercializadas no varejo em embalagem fechada e a granel /

Girio, Thais Marino Silva. January 2007 (has links)
Orientador: Luiz Augusto do Amaral / Banca: Luiz Francisco Zafalon / Banca: Maria da Glória Buzinaro / Resumo: Nos últimos anos, o segmento de alimentos para animais de estimação no Brasil apresentou um expressivo crescimento no volume de vendas. O mercado brasileiro de rações para cães apresenta os maiores índices de crescimento mundial. Com os objetivos de verificar a qualidade higiênico-sanitária e a influência da venda a granel foram analisadas 15 marcas de rações para cães, em duplicata, oriundas de embalagens fechadas e da comercialização a granel. As amostras foram obtidas no comércio varejista dos Municípios de Jaboticabal e Ribeirão Preto/SP. Foram realizadas as determinações dos números mais prováveis de coliformes totais e termotolerantes, as contagens de bolores e leveduras e microrganismos mesófilos e a pesquisa de bactérias do gênero Salmonella. Os resultados obtidos evidenciaram que não houve diferença significativa nas contagens de bolores e leveduras e microrganismos mesófilos entre as amostras comercializadas em embalagens fechadas e a granel. Entretanto, nas amostras de rações comercializadas em embalagens fechadas foram verificadas maiores porcentagens de amostras contaminadas por bolores e leveduras e maior presença por indicadores de contaminação fecal. Não foram isoladas bactérias do gênero Salmonella nas amostras analisadas. Sugere-se que na comercialização a granel a ração seja embalada, para com isso preservar a qualidade microbiológica do produto. / Abstract: In the past years, pet food segment in Brazil has been experiencing a marked increase in sales' volume. The Brazilian dog food market has the world's highest growth rate. This study is aimed to verify the influence of in bulk sales and the hygienic-sanitary quality of dog food. Fifteen brands of dog food obtained from packages and from in bulk marketed were analyzed in duplicate. The samples were collected from retailers of Jaboticabal y Ribeirão Preto Municipality/SP. The most probable number of total coliforms and heat-resistant ones, the counts of yeasts, molds and mesophils, and Salmonella investigation were performed. Results for counts of yeasts, molds and mesophils showed no statistical significance between packed and in bulk food. However, it was verified that samples of in bulk food had greater percentage of molds, yeasts and fecal indicators contaminations. No bacteria of the genus Salmonella was found in analyzed samples. This study suggests that in bulk marketing should pack dog food in order to preserve its microbiological quality. / Mestre
174

Estudo eletrocardiográfico em cães geriátricos submetidos à anestesia geral / Electrocardiographic study in geriatrics dogs submited to general anesthesia

Andreza Conti 26 June 2003 (has links)
O traçado eletrocardiográfico, observado durante a anestesia geral, pode diferir morfologicamente do traçado pré-anestésico. O que não se conhece é o grau de influência que os fármacos anestésicos exercem sobre o registro eletrocardiográfico de um cão geriátrico submetido à anestesia geral e a que ponto estas alterações eletrocardiográficas interferem em sua hemodinâmica. Avaliou-se oitenta e dois cães geriátricos (categoria de risco I ou II) foram distribuídos em três grupos: grupo I, cães de pequeno porte (até 10 kg, n=36); grupo II, cães de médio porte (11 a 25 kg, n=27), e grupo III, cães de grande porte (26 a 45 kg, n=19). Além da avaliação eletrocardiográfica, os exames pré-anestésicos constaram de hemograma completo, mensuração sérica de uréia, creatinina, proteína total e albumina; foram feitas mensurações séricas de potássio, cálcio, sódio e magnésio. A medicação pré-anestésica constou de acepromazina associada à morfina ou a meperidina ou somente morfina. A indução foi feita com propofol ou propofol associado ao midazolam, e a manutenção da anestesia realizada com isofluorano em oxigênio a 100%. Durante a anestesia, os cães foram monitorados continuamente com auxílio de um eletrocardiógrafo computadorizado que avaliou o ritmo cardíaco, a freqüência cardíaca, o intervalo PR, a largura e a morfologia do complexo QRS, o segmento ST, a morfologia, a amplitude e a polaridade da onda T. Avaliou-se também a pressão arterial sistólica, média e diastólica; a freqüência respiratória; a ventilação avaliada através da observação da concentração de dióxido de carbono expirado e dos valores de pressão parcial de dióxido de carbono no sangue arterial; a oxigenação, avaliada através da oximetria de pulso, da pressão parcial de oxigênio no sangue arterial e da saturação da oxi-hemoglobina arterial. Os animais foram submetidos à ventilação assistida ou à controlada quando observou-se hipoventilação e hipercapnia. Nos três grupos, o ritmo cardíaco mais freqüente foi o sinusal normal (88%). Observou-se taquicardia sinusal em alguns momentos do trans-operatório em 9% dos animais. Pouco freqüente, mas com importância hemodinâmica, observou-se bradicardia sinusal (3%) associada à hipotensão. Assim, neste estudo o isofluorano não proporcionou o aparecimento de arritmias e promoveu estabilização hemodinâmica dos animais. Observou-se aumento não significante do intervalo PR que do ponto de vista biológico deve ser considerado importante, visto que aproximadamente 11% dos animais que apresentavam intervalo PR normal com ritmo sinusal , evoluíram para bloqueio atrioventricular de primeiro grau. Observou-se bloqueio atrioventricular de primeiro grau em 2% dos animais no eletrocardiograma pré-anestésico, e 1% evoluiu com bloqueio atrioventricular de 2o grau Mobitz tipo I. As alterações no segmento ST e onda T durante o período trans-anestésico, foram muito freqüentes e relacionadas principalmente a hipoventilação. / The electrocardiogram observed during the general anesthesia, can differ from the morfology of the preanesthetic record. It is unknown the influence of the anesthetic drugs in the electrocardiographic record of a elderly dog during general anesthesia, and if electrocardiographic disturbances interfere in their hemodynamic. Eighty two geriatrics dogs (risk category I or II) were evaluated and distributed in three groups: group I, small-size breeds (less than 10 kg, n=36); group II, medium-size breeds (11 to 25 kg, n=27), and group III, large-size breeds (26 to 45 kg, n=19). Beyond electrocardiographic evaluation, the preanesthetic profile consisted in packed cell volume, seric measurement of urea, creatinine, total protein and albumin; the eletrolytes (potassium, calcium, sodium and magnesium). The preanesthetic medication consisted in acepromazine with morphine or meperidine or only morphine. Anesthesia was induced with propofol or propofol with midazolam and maintained with isoflurane in 100% oxygen. During the anesthesia, the animals were monitoried with a continued computadorized electrocardiogram, recording rhythm, heart rate, P-R interval, QRS complex, ST segment and T wave. The systemic blood pressure (systolic, mean and dyastolic), the respiratory rate, the end-tidal carbon dioxide, partial pressure of arterial CO2, the arterial oxygen saturation, the partial pressure of arterial oxygen and oxygen saturation of hemoglobin were evaluated continuously. The animals were submitted to assisted or controled ventilation when hypoventilation and hypercapnia were observed. In the three groups, the normal sinus rhythm was more common (88%). Sinus tachycardia was observed in 9% of the animals. Sinus bradycardia and a decrease in the systemic blood pressure was observed in 3% of the animals. In view of the results obtained it is possible to conclude that, the isoflurane didn\'t provide the observation of arrhythmias and it gave hemodynamic stability. The prolonged P-R interval was observed although of no statistical significance. However it is important, because 11% of the animals that have prolonged P-R interval, developed first degree atrioventricularricular block. First degree AV block was observed in 2% of the animals in the preanesthetic electocardiogram, and 1% developed second degree AV block Mobitz I during the anesthesia. The changes of ST segment and T wave during the anesthetic proceeding was too common and it was related to hipoventilation.
175

Estudos biol?gicos de Rhipicephalus sanguineus e intera??o Rickettsia rickettsii, R. sanguineus e c?es em condi??es laboratoriais. / Biological studies on Rhipicephalus sanguineus and interactions of Rickettsia rickettsii, R. sanguineus and dogs under laboratory conditions.

Piranda, Eliane Mattos 29 February 2008 (has links)
Made available in DSpace on 2016-04-28T20:16:26Z (GMT). No. of bitstreams: 1 2008- Eliana Mattos Piranda.pdf: 1406016 bytes, checksum: c9a77c6cc1de7bc1adde1a6eb06a7a84 (MD5) Previous issue date: 2008-02-29 / Funda??o de Amparo a Pesquisa do Estado de S?o Paulo / The bacterium Rickettsia rickettsii is the etiological agent of an acute, severe human disease called Rocky Mountain Spotted Fever in the United States or Brazilian Spotted Fever in Brazil. The infection occurs through the tick bite. Reports of clinical illness on dogs due to this agent have been restricted to the United States. The brown dog tick or kennel tick, Rhipicephalus sanguineus (Latreille, 1806) is the most widespread tick species throughout the tropics and subtropics. Biological studies on ticks are very important to the tick-borne pathogens transmission knowledge. For this purpose, the present study evaluated experimental infection of dogs with a Itaia?u (Mogi das Cruzes/ S?o Paulo, Brasil) strain of R. rickettsii and some biological aspects of Rhipicephalus sanguineus. Initially, dogs were infected with R. rickettsii its susceptibility and the role of R. sanguineus as a vector was verified. In the second part the viability of adults ticks (R. sanguineus) on three different temperatures were tested. Ticks were maintained under the controlled conditions of 18 ? 1&#9702;C, 27 ? 1&#9702;C e 32 ? 1&#9702;C e 80 ? 5% (temperature ? humidity) for different times without feed. The dogs were susceptible to R. rickettsii infection. R. sanguineus was able to acquire the pathogen and to transmit R. rickettsii to guinea pigs. Based on the second part s results, R. sanguineus viability is affected by both, temperature and unfed time. / A bact?ria Rickettsia rickettsii ? o agente etiol?gico de uma doen?a aguda e severa em humanos denominada Rocky Mountain Spotted Fever nos Estados Unidos e Febre Maculosa Brasileira no Brasil. A infec??o se d? pela picada de carrapatos. Relatos da doen?a cl?nica nos c?es s?o restritos aos EUA. O carrapato marrom do c?o ou carrapato dos canis, Rhipicephalus sanguineus (Latreille, 1806), ? a esp?cie de carrapato mais freq?ente nos tr?picos e subtr?picos. Estudos da biologia de carrapatos s?o de grande import?ncia para o entendimento da transmiss?o de biogentes. O objetivo do presente trabalho ? avaliar experimentalmente a infec??o nos c?es com R. rickettsii cepa Itaia?u (Mogi das Cruzes/ S?o Paulo, Brasil) e aspectos da biologia de Rhipicephalus sanguineus. Na primeira etapa, c?es foram infectados com R. rickettsii e avaliou-se a susceptibilidade dos animais a infec??o e o comportamento de R. sanguineus como vetor. No segundo experimento, adultos de R. sanguineus tiveram a viabilidade de infestar novos hospedeiros analisada. Os carrapatos foram mantidos a18 ? 1&#9702;C, 27 ? 1&#9702;C e 32 ? 1&#9702;C e 80 ? 5% UR por tr?s per?odos de jejum. Observou-se que os c?es s?o suscept?veis a infec??o por R. rickettsii cepa Itaia?u. Foi verificado que R. sanguineus se infectam com R. rickettsii e s?o capazes de transmitir o agente a cobaias. Baseado nos resultados do segundo experimento, concluem-se que R. sanguineus tem a viabilidade influenciada pela temperatura e tempo de jejum.
176

Incidence of Bradycardia, Hypotension, Bradycardia with Hypotension and Their Risk Factors in Dogs Undergoing General Anesthesia

Hung-Chun Lin (6861473) 16 October 2019 (has links)
<div><b>Background:</b> Bradycardia and hypotension are complications commonly occurring during general anesthesia in small animals. Intraoperative hypotension has been found to be associated with adverse postoperative consequences. </div><div><br></div><div><b>Objectives: </b>The objectives of his study were first, to determine the incidence of bradycardia, hypotension, and bradycardia with hypotension in dogs undergoing general anesthesia, and second, to identify the risk factors associated with these three complications. The third objective was to evaluate the relationship between these three intraoperative complications and the recovery quality in these dogs.</div><div><br></div><div><b>Methods and Materials:</b> A retrospective cohort study was performed using anesthetic records from 250 dogs undergoing general anesthesia between May 23, 2018 and October 1, 2018 at the Purdue University Veterinary Teaching Hospital. Intraoperative bradycardia was defined as heart rate < 60 beats/min for at least two consecutive readings at 5 minutes apart. Hypotension was defined as mean arterial pressure (MAP) < 60 mmHg or a systolic arterial pressure (SAP) < 80 mmHg for at least two consecutive readings. A univariate analysis followed by multiple logistic regression was performed to build the model for bradycardia, hypotension, and bradycardia with hypotension. The relationships between the three complications and the recovery quality were analyzed using the Pearson’s chi-square test.</div><div><br></div><div><b>Results:</b> The study found that out of the 250 dogs, 114 (45.6%) developed bradycardia, 113 (45.2%) developed hypotension, and 32 (12.8%) dogs developed bradycardia with hypotension. The use of dexmedetomidine-based tranquilizers/sedatives, longer duration of anesthesia, and subjection to orthopedic and neurologic surgical procedures were all identified as risk factors for the dogs to develop bradycardia. The use of acepromazine-based tranquilizers/sedatives, young and old age dogs, and dogs subjected to neurologic surgery were associated with the development of intraoperative hypotension. When the length of the anesthesia increased, the chance for developing bradycardia with hypotension increased. There was no significant association between these intraoperative complications and the recovery quality.</div><div><b><br></b></div><div><b>Conclusions:</b> We found a high incidence of bradycardia or hypotension while a much lower incidence of bradycardia with hypotension in the anesthetized dogs. The risk factors for bradycardia were the use of dexmedetomidine-based tranquilizers/sedatives, the longer duration of anesthesia, and the performance of orthopedic surgery and neurosurgery. The risk factors for hypotension included the use of acepromazine-based tranquilizers/sedatives, the older or younger age of dogs, and the performance of neurosurgery. The risk factor for bradycardia with hypotension was the longer duration of anesthesia. While these adverse events developed intraoperatively, we could not identify a direct influence of these complications on the recovery quality. </div><div><br></div>
177

Factors Influencing Relocation Success of Utah Prairie Dog (Cynomys parvidens)

Curtis, Rachel 01 December 2012 (has links)
Utah prairie dogs (Cynomys parvidens) have been extirpated in 90% of their historical range. Because most of the population occurs on private land, this threatened species is continually in conflict with landowners. The Utah Division of Wildlife Resources has been relocating prairie dogs from private to public land since the 1970s, but relocations have been largely unsuccessful due to high mortality. Prairie dogs are highly social animals, but they are usually relocated without regard to their family group (coterie). I hypothesized that relocating Utah prairie dogs with their social structure intact may positively affect their survival rates and behavior. Utah prairie dogs were relocated from the golf course in Cedar City, Utah to two prepared sites near Bryce Canyon National Park, Utah in 2010 and 2011. Trapped animals were individually marked, and released at the new sites. Prairie dogs were relocated as coteries, or in a control group as randomly trapped individuals. To compare the two sites, vegetation transects were established at each site to document differences in composition and structure. Two months after relocation, traps were set to recapture released animals. Activity budgets were collected prior to, and following, relocation. Activity data were also collected on wild prairie dog populations for comparison. The best predictor of survival and recapture rate was the animal’s weight at initial capture. Larger animals had higher survival, but lower recapture rates. More research is needed to determine if this is due to better body condition, older animals having more experience, or both. Analysis showed no evidence of an advantage to relocating Utah prairie dogs by coteries. There was no benefit to survival, and no difference in behavior between coterie and control relocation strategies. Relocated animals behaved differently from non-relocated prairie dogs. While still significantly different, relocated individuals behaved more like wild prairie dogs than the animals at the urban source population. The vegetation at the two sites was significantly different. One site had significantly less grass cover, more invasive plant cover, and rockier soils. The sites also had different soil structures, which affect burrowing, and long-term retention rates. More research is needed to determine how site selection influences long-term success of a relocation site.
178

The Utah Prairie Dog: Abundance, Distribution, and Habitat Requirements

Collier, G. Donald 01 May 1975 (has links)
Objectives of this study were: (1) to determine the status of the utah prairie dog (Cynomys parvidens, Allen), a rare mammal endemic to southcentral Utah, and (2) to identify habitat factors which limit densities of this species. Seven components of the habitat were studied: barriers, other animals, soil, temperature and precipitation, topography, vegetation, and water. Prior to collection of habitat data, virtually all populations of the species were found by extensive searching and interviewing; the number of animals and the area occupied were determined for each population. Results justified the endangered status of the Utah prairie dog. Area occupied by this prairie dog was reduced by an estimated 87 percent during the past 50 years. During this time, the animals disappeared from 34 localities. Recently, total numbers also were reduced: between 1970 and 1971, the total population dropped from an estimated 8, 600 animals to 5, 700. Only 48 substantial populations existed in 1971. Six other populations were exterminated the preceding year by rodent control. Although the loss of prairie dogs between 1970 and 1871 resulted from rodent control, another loss between 1971 and 1972 resulted from drought. A drought decimated all populations in regions without water. Topographic region, which reflected water available to plants, was more strongly correlated to density of this prairie dog than any other parameter (r20' • 67). The crucial role of water was confirmed by analysis of vegetative parameters. Since grasses, forbs, and shrubs have distinctive water contents, they indicated prairie dog response to plant water. Forb cover, which contains the highest relative water content, was the only type of cover that was positively correlated to the density of these animals. Shrubs, with the lowest water content, were negatively correlated; and grasses, with an intermediate water content, were neutral relative to density. Two other parameters also demonstrated the critical nature of water: the mean number of grasses, forbs, and shrubs, and heterogeneity among plant communities. No other parameters were significant (p :::_. 05) in multiple regression. Together, these explained 75 percent of the variability in abundance of the Utah prairie dog. The mean number of grasses, forbs, and shrubs was negatively correlated with density; coefficients of this parameter probably reflected the time required for prairie dogs to select plant parts with adequate water. On the other hand, heterogeneity among plant communities was positively correlated to density, and indicated emergency sources of plant water. Such water probably allowed prairie dogs to avoid population reductions otherwise associated with drought. The critical nature of plant water is especially meaningful in light of long-range drying trends. The Utah prairie dog's habitat has become progressively drier during the past several thousand years. If these trends continue, the animal may become extinct. However, their possible extinction can be delayed by transplanting animals to sites adjacent to streams or irri[;ated fields. Transplanting also can help solve the secondary problem of rodent control: since prairie clogs are often eradicated on private lands, transplant sites should be controlled by the public. Public lands in southern Utah usually contain little water; therefore, purchase of certain private lands with adequate water for the animals is a key to managing this unique prairie dog.
179

The ecology and conservation biology of the endangered African wild dog (Lycaon pictus) in the Lower Zambezi, Zambia

Leigh, Kellie A January 2006 (has links)
Doctor of Philosophy / The African wild dog (Lycaon pictus) is one of Africa’s most endangered carnivores. Previous research into this species has focussed on the largest extant populations in Africa. However, there are a large number of relatively small populations (20 to 50 dogs) distributed across Africa, which represent an important component of the diversity of the species and its remaining habitat. This study investigated the status of a small population of wild dogs in the Lower Zambezi area in Zambia. Objectives focussed on assessing population dynamics and identifying causes of decline. Research was carried out over a broad range of topics in an effort to provide comprehensive information for conservation management of the population. The scope of the project was divided into five sections: 1) Demography and pack dynamics were assessed to identify the structure and status of the population, and the main causes of mortality. 2) An assessment of habitat types and related ecological factors was carried out to determine wild dog habitat utilisation in relation to vegetation type, prey densities and hunting success in each area. 3) The effects of interpredator competition on wild dog population dynamics was investigated, specifically, the effects of lions (Panthera leo) and spotted hyaenas (Crocuta crocuta). 4) Genetic analyses were carried out to assess the historic and contemporary genetic variability of the population, and to define patterns of geographic structuring and population differentiation. 5) Results were combined to assess the viability of the population and recommend conservation management strategies. Snaring was identified as the most important cause of adult mortality, and a threat to wild dog population persistence. Inbreeding avoidance led to the emigration of adult males and females from the area and appeared to be a substantial contributor to population decline. Limited mate selection corresponded with neither sex displaying philopatry and large dispersal distances effectively removed adults from the population. This result has important implications for the management of small populations, whereby lack of mate choice may increase dispersal distances and thereby increase edge effects on populations, regardless of home range sizes. Home range sizes were related to den locations in remote areas of the Zambian Escarpment, which was used as a breeding refuge area. The Zambezi River and Zambian Escarpment appeared to be effective barriers to wild dog home range movements. The study area contained a diversity of habitats on the alluvial terraces of the river valley floor. There was a high density of impala (Aeypceros melampus), which formed the main prey base for the wild dog population. Studies of other populations have found that wild dogs often avoided areas with high competing predator densities, which corresponded with high prey density areas. In contrast to those findings, the Lower Zambezi wild dog population showed a strong preference for high prey density areas. This population also showed only temporal avoidance of high lion density areas. Low lion density areas were preferred during breeding periods, while moderate to high lion density areas were preferred during non-breeding periods. Direct predation of adult wild dogs by lion and spotted hyaenas was rare. Kleptoparasitism of wild dog kills by either competing predator species was also rare. Predator competition was not considered to be an important determinant of population decline. The Lower Zambezi population suffered from a loss of heterozygosity, low allelic richness, and there was significant evidence of a recent population bottleneck. The population did not contain any new mtDNA haplotypes, nor any unique alleles on the commonly used microsatellite loci, but was differentiated from African wild dog populations in other regions. There was evidence of historical and recent gene flow between the Lower Zambezi and the neighbouring southern African populations of Hwange and Okavango. This was the first study to show a loss of genetic variability in a free-ranging African wild dog population. Although more immediate anthropogenic and demographic factors were the critical determinants of population decline, the loss of genetic variability has important implications for the conservation of the remaining small and fragmented wild dog populations in Africa. Results showed that due to its small size the population is likely to have suffered from inverse density dependence and Allee effects on dispersal and reproductive success. Management recommendations focussed on mitigating anthropogenic causes of mortality, and improving connectivity with a larger, potential source population to increase the probability of successful dispersal and to restore genetic diversity. The high density prey base, small home range sizes and low levels of interpredator competition detected in this study suggest that the area has the capacity to support a large and potentially viable population of wild dogs if appropriate management strategies are implemented.
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The biology of the European red fox and the free roaming dog on Bherwerre Peninsula, Jervis Bay

Meek, Paul D., n/a January 1998 (has links)
This thesis provides an insight into the biology and ecology of foxes Vulpes vulpes from a coastal habitat and free roaming dogs Canis lupus familiaris from an Aboriginal community, both in SE NSW. In particular, the study examines the home range and movement patterns of both canids from a view point of population and disease control. Additional base line information was collected for these species on diet, parasites and population biology. A total of 14 foxes and 10 dogs were collared and radio tracked to determine the home range and movement patterns of the animals. The data collected provides information on the behaviour of foxes in coastal habitat and represents the first detailed biological study of freeroaming dogs in Australia. The results provide a better understanding of dog movements, particularly the differences in behaviour between wandering and sedentary dogs. Home range sizes varied greatly between the dog groups from 1 ha to 2451 ha. There was evidence that dog forays were influenced by prey availability, particularly medium sized macropods. Occasional sallies, size and shape of fox and dog home range is discussed in relation to the richness of habitat at Jervis Bay with comparisons being made with other studies from the literature. Foxes in Jervis Bay had home ranges between 60-270 ha which is comparable to foxes living in the forests of Germany and in coastal habitat in the Netherlands This study also provides data on the diet of foxes and dogs presenting quantitative and qualitative data on food preferences. Foxes tended to be opportunistic in food selection although critical weight range mammals ie. ringtail possums were favoured. The high prevalence of the parasite Spirometra spp. in foxes indicated that considerable numbers of amphibians and reptiles are consumed by this species. A comprehensive inventory of the parasites of the two canid species showed a high proportion of hookworm in foxes and dogs and Spirometra spp in foxes. These results are discussed in light of the potential health implications for local Aboriginal people. Analysis of fox scats revealed that they have the potential to spread the seeds of bitou bush. A more detailed pilot study revealed the potential impact of foxes on the environment through the spread of weed seeds. Germination trials recorded high viability of seeds that were eaten and deposited by foxes. The management implications of this behaviour are discussed in context to weed control. This thesis has provided new information on foxes and dogs in Australia. Discussion on these species in the thesis has been framed around the benefits of this information for population and disease control.

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