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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.
11

Correlações da biometria ultrassonográfica testicular com medidas prostáticas e corporais em cães / Correlations of testicular ultrasound biometry with prostatic and body measurements in dogs

Denise Gonçalves 15 December 2015 (has links)
Foram realizadas as biometrias ultrassonográficas testiculares e prostáticas, e mensurações corporais como altura de cernelha, comprimento do corpo, estatura e peso corporal de 54 cães inteiros, com idade entre 24 e 50 meses e escore corporal definido eliminando animais obesos. As medidas testiculares apresentaram correlação positiva forte com as medidas prostática, medidas corporais e peso metabólico (p<0,001), e correlação positiva moderada com o índice de massa corporal canino (IMCC). Foi possível determinar um intervalo de confiança entre as medidas testiculares e prostáticas no grupo de animais estudados e elaborar equações lineares simples para se estimar as medidas prostáticas a partir das medidas testiculares. Definiu-se equações utilizando o comprimento testicular (CT) ou o diâmetro testicular (DT) em centímetros. Comprimento próstata = CT x 0,82 (r2 = 0,97); Comprimento da próstata = DT x 1,27; Altura próstata = CT x 0,72 (r2 = 0,97); Altura da próstata = DT x 1,12; Largura próstata = CT x 0,85 (r2 = 0,96); Largura da próstata = DT x 1,32. Não houve diferença estatisticamente significativa entre as dimensões de comprimento e diâmetro dos testículos direito e esquerdo / The ultrasound biometry of testicular and prostate as well as body measurements such as withers height, body length, height and weight were done of 54 dogs, aged between 24 and 50 months and body condition defined eliminating obese animals. The testicular measurements showed strong positive correlation with prostate size and body measurements as well as with metabolic weight (p < 0,001), and moderate positive correlation with de canine body mass index (IMCC). It was possible to determine a confidence interval between testicular and prostate measures. Simple linear equations to estimate prostate measures from the testicular measures were done. The equations was defined using testicular length or testicular diameter in centimeters. Prostate length = testicular length x 0,82 (r2 = 0,97); Prostate length = testicular diameter x 1,27; Prostate height = testicular length x 0,72 (r2 = 0,97); Prostate length = testicular diameter x 1,12; Prostate width = testicular length x 0,85 (r2 = 0,96); Prostate widht = testicular diameter x 1,32. There was no statistically significant difference between the dimensions of the right and left testicles
12

Correlação de medida ultrassonográfica com o volume hepático medido através do deslocamento de água em cães / Correlation of ultrasound measurement with liver volume measured by water displacement in dogs

Mariana Silva de Salles Pacheco 30 November 2015 (has links)
O tamanho do fígado é um critério importante para o diagnóstico diferencial de cães com suspeita de doenças hepáticas, porém, há uma carência na literatura veterinária no que se refere à avaliação de seu volume, principalmente pelo ultrassom, que é considerado um excelente recurso para avaliação desse órgão. Para se obter uma maneira prática e de simples execução de se mensurar o volume hepático através da ultrassonografia, foram realizadas medidas externas (altura, largura e perímetro do tórax) e medidas ultrassonográficas lineares do fígado de 82 cadáveres de cães, de idades e raças variadas, por dois observadores. Essas medidas foram correlacionadas com o volume hepático determinado por deslocamento de água, através de regressões lineares. As equações obtidas por regressão linear foram: Volume hepático (ml) = 639 + 10 &rho; + 75 medA - 55h - 23peri + 1,4h &#42 peri (r2 ajustado = 0,81; p &lt; 0,01), Volume hepático (ml) = 822 + 14 &rho; + 59 medE - 59h - 28peri + 1,7h &#42; peri (r2 ajustado= 0,83; p < 0,01), e Volume hepático (ml) = 30 + 0,3 &#42; x (r2 = 0,88; p < 0,01), onde peri = perímetro do tórax (cm); &rho;= peso corporal (kg); medA = medida ultrassonográfica.A (cm), mensurada do início do parênquima hepático até o diafragma, tangenciando o colo da vesícula biliar; medE= medida ultrassonográfica.E (cm), mensurada na linha média, da borda caudal do fígado até o diafragma; h = altura do tórax (cm) e; x = h &#42; largura do tórax &#42; medA. A associação entre medidas ultrassonográficas hepáticas com o peso corpóreo, assim como com a altura e o perímetro torácicos permitiu boa correlação com o volume hepático. As medidas ultrassonográficas estabelecidas mostraram-se reprodutíveis por um mesmo observador ou observadores diferentes / The liver size is an important criterion for differential diagnosis of dogs with suspected liver disease, however, there is a lack in the veterinary literature regarding estimation of liver volume, especially by ultrasound, which is considered an excellent resource for evaluation of that organ. In order to obtain a practical and simple method of measuring liver volume by ultrasonography, external measures (height, width and girth of the chest) and linear ultrasound measures of the liver of 82 dog corpses of various ages and breeds were done by two observers. By linear regression these measures were correlated with liver volume, determined by water displacement. The equations obtained were: Hepatic volume (ml) = 639 + 10 &rho; + 75 medA - 55h - 23peri + 1.4h &#42; peri (adjusted r2 = 0.81; p < 0.01), Hepatic volume (ml) = 822 + 14 &rho; + 59 medE - 59h - 28peri + 1.7h &#42; peri (adjusted r2 = 0.83; p < 0.01), and Hepatic volume (ml) = 30 + 0,3 &#42; x (adjusted r2 = 0,88; p < 0,01), where peri = perimeter of the chest (cm); = body weight (kg); medA = ultrassonographic measurement A (cm), from the beginning of the hepatic parenchyma to the diaphragm tangent to the neck of the gallbladder; MedE= ultrassonographic measurement.E (cm), from the caudal border of the liver to the diaphragm, measured on the midline; h = height of the chest (cm) and; x = h &#42; width of the chest &#42; medA. The association of liver ultrasound measures with the weight, height and thoracic perimeter provided good ground for a correlation with the liver volume. The ultrasound measures proved to be reproducible inter as well as intra observer
13

Informacijos perdavimo lytiniais feromonais tyrimas Canis familiaris pavyzdžiu / Information transfer by means of sex pheromones in test object Canis familiaris

Juškevičiūtė, Justina 16 August 2007 (has links)
Dabar vis daugiau mokslininkų bando identifikuotus gyvūnų feromonus sintetinti ir panaudoti praktinėms reikmėms, pavyzdžiui, vabzdžių sintetinių feromonų analogus naudoti kovai su žemės ūkio kenkėjais. Tačiau tik XX amžiaus pabaigoje pradėta domėtis ir žinduolių feromonais. Viena iš naujų tiriamų sričių yra: lytinių feromonų įtaka gyvūnų lytinei elgsenai. Lytinė elgsena yra vienas iš svarbiausių šunų kaip ir, bet kurios kitos gyvosios sistemos egzistavimo garantas, todėl tai paskatino mus išsamiau paanalizuoti šunų lytinės elgsenos modelį (asistavimą). Taip pat mūsų tikslas buvo sumodeliuoti tokį biotestavimo modelį kaip materiali informacija paveikia individo (šuns) elgesį ir nustatyti bei apibūdinti kas tai yra ta informacija, šiuo atveju – cheminė medžiaga. Tyrimai buvo atlikti 2005 – 2007 metais. Buvo surinkti šlapimo ėminiai iš skirtingų šunų veislių devynių kalių nerujos ir rujos metu. Ėminių rinkimo metodika buvo specialiai sukurta įgyvendinti mūsų užduotis ir yra originali. Viena dalis rinkimo metu surinktos medžiagos buvo išsiusta į Karališkąjį Technologijų Institutą Stokholme (Royal Institute of Technologies). Atlikus pirminius ėminių tyrimus, nustatyta jog tik rujojančių kalių šlapime yra TC medžiaga. Antra dalis rinkimo metu surinktos medžiagos buvo naudota biotestui. Po to buvo atlikti du biotestavimai lauko sąlygomis Pietų Rusijos aviganių veislyne „Balandis“. Šiuose tyrimuose buvo atlikti testavimai su šios veislės patinais pagal 7 mūsų sukurtus testavimo... [toliau žr. visą tekstą] / More and more scientists nowadays are trying to syntetic animals‘ pheromones and use them for practical purposes. Analogues of syntetic pheromones, for instance, are used in agriculture against pests. It was only in the end of the 20th century, however, that mammals‘ pheromones, too, started arousing interest. One of the new fields of resaerch is the animals‘ sexual behaviour. Sexual behaviour is one of the guarantees of dogs‘, as well as any other living systems‘ existence. Then an idea suggested itself to us to analyze more deeply the model of this type of behaviour amoung dogs. Our aim was also to set up a model of biotesting in what way material information is reflected on an individual‘s (dog‘s) behaviour and to establish what that information is. In this case – a chemical substance. The research was carried out between 2005 and 2007. Urine samples were gathered from bitches of different dogs‘ breeds then they were on the heat and when they were not on the heat. The method of taking the samples was specially created to satisfy our requirements and is original. One part of the samples gathered was sent to the Royal Institute of Technologies in Stockholm. The research conducted on the primary samples showed that the substance TC was to be found only in the urinie of bitches (females) that were on the heat. The rest of material gathered was used for examination. Then two biotests (in outside)was conducted at the South Russian Sheep – dog kennel “Balandis“. Researched... [to full text]
14

Aspectos epidemiológicos da leishmaniose visceral em Sergipe e liberação de redes extracelulares de neutrófilos em cães e humanos na infecção por Leishmania infantum / Epidemiological aspects of visceral leishmaniasis in Sergipe and release of extracellular networks of neutrophils in dogs and humans on infection with Leishmania infantum

Campos, Roseane Nunes de Santana 06 June 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Visceral Leishmaniasis (VL) is a serious infectious disease and is increasing geographical expansion and urbanization. patterns of transmission of the disease are altered due to human actions. The dog is considered the main reservoir of the parasite. The development of the disease depends in part on the host immune system. Neutrophils are considered the first line of defense against pathogens and important agents in the control of LV. These cells have an additional mechanism to eliminate microorganisms that occur with the release of extracellular networks (Neutrophil Extracellular Traps -NETs). This work has two overall objectives, the first being an epidemiological study of LV in Sergipe and the second evaluation of NETs formation in human neutrophils and dogs with LV stimulated with L. infantum, so this thesis was divided into chapters, for better understanding. Epidemiological evaluation were used SINAN data and serosurveys canines Zoonosis Aracaju-SE. A descriptive analysis of the data and construction of distribution maps of disease was performed. Sergipe Aracaju and from 2008 to 2014 the incidence rate in humans with LV increased and the percentage of infected dogs has doubled in the capital. The percentage of cases positive for human VL by sex, according to the age of the patient group, showed that over 15 years the disease affects more males. The spatial distribution analysis allowed to view areas of the city with the highest concentration of human and canine VL. The neighborhoods located in poor areas or growing areas were those with the highest incidence of the disease in humans and dogs. The results show that presents endemicity for human and canine VL. In order to evaluate the formation of NETs were used human groups: Control; LV treated and positive DTH. The dogs were divided into control; Asymptomatic and symptomatic. Neutrophils were isolated from patients with LV University Hospital / UFS and dogs diagnosed with VT by Zoonoses were incubated with and without stimulation of parasite and NETs measures in the supernatant of the cultures after 90 minutes. The parasitic load determined after 24 and 48 hours of interaction with neutrophils treated by the limiting dilution technique. In the evaluation of NETs induction of human neutrophils and release dogs with LV greater amount of NETs when stimulated with L. infantum. When compared between the groups individuals positive DTH release fewer NETs stimulated or not with the parasite. At 24 and 48 hours LV treated subjects have a higher parasite load and showed positive DTH fewer parasite than the other groups tested. Dogs with LV release signals greater amount of NETs when stimulated with L. infantum and have higher parasitic load after 48 hours. It is observed that the release of NETs and control of parasitic load by neutrophils varies according to the clinical form of the LV, in humans and dogs. / A Leishmaniose Visceral (LV) é uma doença infecciosa grave e está em crescente expansão geográfica e urbanização. Os padrões de transmissão da doença são alterados devido às ações antrópicas. O cão é considerado o principal reservatório do parasito. O desenvolvimento da doença depende em parte do sistema imune do hospedeiro. Os neutrófilos são considerados a primeira linha de defesa do organismo contra agentes patogênicos e importantes no controle da LV. Estas células têm um mecanismo adicional para eliminar microorganismos que ocorre com a liberação de redes extracelulares (Neutrophil Extracelular Traps -NETs). Este trabalho teve dois objetivos gerais, sendo o primeiro um estudo epidemiológico da LV em Sergipe e o segundo a avaliação da formação de NETs em neutrófilos de humanos e cães com LV estimulados com L. infantum, assim essa tese foi dividida em capítulos, para melhor compreensão. Na avaliação epidemiológica foram utilizados dados do SINAN e inquéritos sorológicos caninos do Zoonoses de Aracaju-SE. Foi realizada uma análise descritiva dos dados e construção de mapas de distribuição da doença. Em Sergipe e Aracaju de 2008 a 2014 o coeficiente de incidência em humanos com LV aumentou e o percentual de cães infectados dobrou na capital. A porcentagem de casos positivos para LV humana por sexo, de acordo com a faixa etária do paciente, mostrou que acima de 15 anos a doença acomete mais o sexo masculino. A análise de distribuição espacial permitiu visualizar áreas da cidade com maior concentração de LV humana e canina. Os bairros situados em áreas com situação econômica desfavorável ou em zonas de expansão foram os que apresentaram maior incidência da doença em humanos e cães. Os resultados demonstram que apresenta caráter endêmico para a LV humana e canina. Com a finalidade de avaliar a formação de NETs foram utilizados grupos humanos: Controle; Tratados LV e DTH positivos. Os cães foram divididos em: Controle; Assintomáticos e sintomáticos. Foram isolados neutrófilos de pacientes com LV do Hospital Universitário/UFS e de cães diagnosticados com LV pelo Zoonoses foram incubadas, com e sem estímulo do parasito e NETs medidas no sobrenadante das culturas após 90 minutos. A Carga parasitária determinada após 24 e 48 horas de interação com neutrófilos tratados, através da técnica de diluição limitante. Na avaliação da indução de NETs, os neutrófilos de humanos e cães com LV liberam maior quantidade de NETs quando estimulados com L. infantum. Quando comparado entre os grupos indivíduos DTH positivos liberam menor quantidade de NETs estimulados ou não com o parasito. Em 24 e 48 horas indivíduos tratados com LV apresentam maior carga parasitária e os DTH positivos demonstraram menor quantidade do parasito do que os outros grupos testados. Os cães com sinais de LV liberam maior quantidade de NETs quando estimulados com L. infantum e apresentam maior carga parasitária após 48 horas. Observa-se que a liberação de NETs e o controle da carga parasitária através dos neutrófilos variam de acordo com a forma clínica da LV, em humanos e cães.
15

Ocorrencia de cães domesticos (canis familiaris) em fragmentos de mata atlantica em zona rural e urbana e sua relação com a ocupação humana do entorno / Domestic dogs (canis familiaris) in atlantic forest fragments in rural and urban areas and their relationship with the surrounding human occupation

Torres, Patricia Carignano 04 March 2008 (has links)
Orientador: Paulo Inacio de Knegt Lopez de Prado / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T22:02:28Z (GMT). No. of bitstreams: 1 Torres_PatriciaCarignano_M.pdf: 994827 bytes, checksum: 783f69cfeebf179301aa38f51ed8b078 (MD5) Previous issue date: 2008 / Resumo: O cão doméstico tem atuado como espécie exótica invasora, perturbando e modificando ecossistemas nativos de diferentes maneiras. Porém, pouco se sabe sobre o tamanho da população de cães que habitam locais próximos a áreas de interesse ambiental e se isso pode influenciar a chance de entrada desses animais em tais áreas. Além disso, apesar de sua estreita ligação com a população humana, pouco se sabe sobre a relação desta com a população de cães. Sendo assim, o presente estudo teve como objetivos estimar o tamanho de populações de cães, em área urbana e rural próximas a fragmentos florestais, entender de que modo a população humana dessas áreas maneja seus cães e qual a freqüência de ocorrência de cães nos fragmentos florestais. Assim, foram feitas entrevistas com os residentes de modo a obter informações sobre o número de cães com dono e o regime de manejo dado a eles, censos de cães soltos nas áreas e foram montadas parcelas de areia dentro dos fragmentos, a distâncias crescentes da borda, para verificar a freqüência de ocorrência dos cães e se ela diferia da borda para o interior. Os resultados indicaram que ter cães é mais comum em área rural, bem como deixá-los soltos fora da propriedade. Apesar disso, o tamanho da população de cães é maior nas áreas urbanas estudadas, devido a grande densidade populacional humana. Também nessas áreas há cães sem dono, algo raro nas áreas rurais estudadas. O tamanho da população de cães no entorno não influencia a freqüência de ocorrência desses animais dentro dos fragmentos e em ambos os ambientes (rural e urbano), os cães parecem ser um efeito de borda nos fragmentos florestais. Apesar de serem pouco freqüentes a distâncias maiores da borda, esses animais foram marcadamente muito mais freqüentes que carnívoros silvestres, podendo ser mais um impacto importante causado pela presença humana nessas áreas. Assim, o efeito direto que os cães domésticos exercem sobre a fauna local é algo que ainda precisa ser estudado no Brasil / Abstract: Domestic dogs (Canis familiaris) have been acting as invasive exotic species in many instances, disturbing and modifying natural ecosystems in many ways. Still, little is know about the dogs population size near areas of conservation interest and if that can influence dog¿s chance of using those areas. In addiction, despite their close relationship with humans, little is know about the people¿s attitudes towards the dog population. Thus, this study intends to estimate dog populations sizes in urban and rural areas near forest patches, to investigate the people¿s attitudes towards dogs in those areas and to quantify dog frequencies inside forest patches. For that purpose, questionnaires with local residents were conducted to obtain information about dogs¿ number and the owners¿ attitudes towards caring for their dogs. Censuses on the areas were conducted to estimate numbers of unrestricted and stray dogs. Scent-stations were installed inside the forest patches, at different distances from the edge, to evaluate the frequency of those animals and see if it differed between patches¿ edge and their interior. Having a dog is more common in the rural area, as well as keeping them unrestricted. Yet, dogs¿ population is larger in the urban areas studied, due to high human densities. Also, in those areas there are stray dogs, which is uncommon in the rural areas studied. The dogs¿ population size in the surroundings don¿t influence their presence inside the forest patches and in both landscapes (rural and urban), dogs seems to be an edge effect. Despite not being very common inside the patches other than in its edge, these animals seem to occur more frequently than wild carnivores. For that reason they can represent another important negative impact cause by the human presence in those areas. Domestic dogs¿ direct effects on wildlife still have to be studied in Brazil, nonetheless these potential impacts can be minored by preventing dogs from entering the forest patches. To do so, the residents¿ attitudes towards dogs, in the surrounding areas, are of extreme importance / Mestrado / Ecologia / Mestre em Ecologia
16

Příčiny dominantní agrese psa domácího (Canis familiaris ) vůči člověku / Causes of canine dominant aggression (Canis familiaris) to people

Suková, Karolína January 2015 (has links)
Karolina Suková Abstract People have been living with dogs (Canis familiaris) in close symbiotic relationship for many thousands of years. Such a kind of coexistence cannot get along without certain risk factors. Although aggression is a natural and wide spread phenomenon in the animal kingdom, manifestation of canine aggression toward people is a public health problem which has to be resolved. Dog bites can cause traumatic injuries to victims and decrease the quality of life or even cause the loss of life to the animal. Therefore there is a serious need to determine the risk factors of dog attacks to people and provide effective preventive strategies to this problem. We consider two kinds of risk factors to be fundamental in this respect: factors depend on the dog (e.g. age, breed, sex and size) and factors depend on the owner (e.g. method of training, prior experience with care of dogs, knowledge of natural behavior of dog, time dedicated to dog etc.). Our study examined this risk factors using a questionaire. Seventy two respondents (owners of both aggressive and non-aggressive dogs) participated on our study. Our results suggest that owner's knowledge of natural behavior of dog, time which the owner dedicates to his dog and sex of the dog correlate significantly with canine aggression toward people. Key...
17

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.
18

Conservation Genetics of Wolves and their Relationship with Dogs

Sundqvist, Anna-Karin January 2008 (has links)
<p>Management of wolves is a complex issue, and molecular genetics is an important tool in this work. Molecular genetics can provide important information at the species, population and individual level, which can be essential for the development of management programs aiming at the long term survival of wolf populations.</p><p>In this thesis I developed new genetic markers on the canine Y chromosome to estimate the number of founders of the Scandinavian wolf population. This knowledge is important to reconstruct the history of the population and to design the most appropriate conservation strategies. Next, genetic markers with different pattern of inheritance have been used to identify hybrids between wolves and dogs. This allowed us to determine the direction of hybridization and to evaluate its possible impact on the gene pool of a wolf population. Furthermore, I also developed a method for a more reliable identification of the predator responsible of an attack by using saliva remains left on the prey. Since predation on livestock is perhaps the main reason for the negative opinions about the predator, the correct identification of the responsible for an attack (wolf, dog or hybrid) is essential. </p><p>Finally, this thesis has also been focusing on the domestication of dogs. By using Y chromosome markers (paternally inherited), it has been possible to complement previous studies based on mtDNA sequences (maternally inherited) and autosomal markers (inherited from both parents). In this way I have obtained a more complete picture of the domestication process and of the origin of breeds. This has shown that there has been a bias in the contribution of the two sexes in the origin of dog breeds (fewer males then females contributing to each breed) and that the origin of dogs was not marked by extensive backcrosses with male wolves over the entire species range.</p>
19

Conservation Genetics of Wolves and their Relationship with Dogs

Sundqvist, Anna-Karin January 2008 (has links)
Management of wolves is a complex issue, and molecular genetics is an important tool in this work. Molecular genetics can provide important information at the species, population and individual level, which can be essential for the development of management programs aiming at the long term survival of wolf populations. In this thesis I developed new genetic markers on the canine Y chromosome to estimate the number of founders of the Scandinavian wolf population. This knowledge is important to reconstruct the history of the population and to design the most appropriate conservation strategies. Next, genetic markers with different pattern of inheritance have been used to identify hybrids between wolves and dogs. This allowed us to determine the direction of hybridization and to evaluate its possible impact on the gene pool of a wolf population. Furthermore, I also developed a method for a more reliable identification of the predator responsible of an attack by using saliva remains left on the prey. Since predation on livestock is perhaps the main reason for the negative opinions about the predator, the correct identification of the responsible for an attack (wolf, dog or hybrid) is essential. Finally, this thesis has also been focusing on the domestication of dogs. By using Y chromosome markers (paternally inherited), it has been possible to complement previous studies based on mtDNA sequences (maternally inherited) and autosomal markers (inherited from both parents). In this way I have obtained a more complete picture of the domestication process and of the origin of breeds. This has shown that there has been a bias in the contribution of the two sexes in the origin of dog breeds (fewer males then females contributing to each breed) and that the origin of dogs was not marked by extensive backcrosses with male wolves over the entire species range.
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Determining the antiquity of dog origins: canine domestication as a model for the consilience between molecular genetics and archaeology

Raisor, Michelle Jeanette 15 November 2004 (has links)
Archaeologists have favored a date of 14,000-15,000 years before present (BP) for canine domestication. However, recent studies of mutations in the mitochondrial DNA sequence by molecular geneticists have implied that dogs were domesticated over 100,000 years ago, which has challenged traditional theory. Geneticists have further hypothesized that dogs originated from wolf ancestors based upon the number of substitutions observed in dog and wolf haplotypes. Although both disciplines provide substantial evidence for their theories, the origin of dog domestication remains controversial. Several areas continue to be debatable. First, both geneticists and archaeologists incorrectly use the term domestication to describe events that clearly can not be proven to under human control. Second, the evolutionary development of canines is viewed by molecular biologists as well as archaeologist to be indicators of domestication without any further exploration of other probable causes. Third, the studies in canine genetics are so complex that most archaeologists have difficulty in providing evidence that would be contradictory to molecular theory. Fourth, both fields of study continually ignore innate behavioral characteristics of wolves that would make domestication highly improbable. Fifth, geneticists rely heavily on data gathered from sequencing of mitochondrial DNA, which has been assumed to maternally inherited. However recent human studies have shown that this assumption has now been proven to be incorrect. And finally, not only are morphological traits of fossilized dogs and wolves so similar that making a taxonomic identification improbable, but also the amount of archaeological remains available are too sparse and fragmented for accurate affiliation. An alternate theory of canine domestication will be proposed utilizing data gathered from the archaeological record and molecular research. I hypothesize that dogs diverged naturally from wolves 100,000 years ago as a result of the natural course of evolution, not human intervention, and had already evolved into a dog prior to being domesticated by humans 14,000-15,000 years ago. Evidence will be presented to clearly show that this hypothesis is a more accurate scenario of canine domestication.

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