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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.
21

Efeito do meio de congelação sobre as características morfofuncionais do sêmen canino

Chirinéa, Viviane Helena [UNESP] January 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2003Bitstream added on 2014-06-13T19:38:33Z : No. of bitstreams: 1 chirinea_vh_me_botfmvz.pdf: 882967 bytes, checksum: dbe4419b2561f045402e0da0d59ad8da (MD5) / Fundação para o Desenvolvimento da UNESP (FUNDUNESP) / Com o objetivo de se avaliar dois meios diluidores - Tris/Glicerol e MP50 - para a congelação do sêmen de cães, foram utilizados ejaculados de 10 cães adultos, colhidos por meio de manipulação digital. As características morfofuncionais foram analisadas no sêmen in natura (T1), refrigerado (T2) e descongelado (T3). As amostras foram avaliadas para: motilidade e vigor espermático, teste hiposmótico, integridade de membrana espermática, morfologia espermática e análise ultra-estrutural, além da mensuração do pH. Após a diluição com os diferentes meios, o sêmen foi envasado em palhetas francesas de 0,5mL, contendo 40 x 106 espermatozóides móveis/palheta, e mantidas por 60 minutos à 5ºC (T2); logo após, foram transferidos para o vapor de nitrogênio durante 20 minutos, e por fim, mergulhadas em nitrogênio. O armazenamento das palhetas foi em botijão criogênico. As palhetas foram descongeladas a 70ºC por 8 segundos. A análise de variância mostrou influência do efeito animal nas variáveis analisadas, com exceção da motilidade espermática e integridade de membrana espermática. O teste hiposmótico, a integridade de membrana espermática e o pH, nas amostras refrigeradas (T2), apresentaram diferença estatística significativa (p<0,05) entre os meios, com superioridade do MP50. Nas análises pós-descongelação (T3), não foram observadas diferenças significativas entre as variáveis estudadas para os dois meios. A análise ultra-estrutural, mostrou edema de membrana plasmática e acrossomal, nas diferentes etapas do processo de congelação. Em conclusão, considerando-se as características morfofuncionais do sêmen canino pós-descongelação, os meios diluidores demonstraram igualdade. / The objective of this study was to verify the efficiency of two different extenders for freezing dog semen: Tris/Glycerol and MP50. Ten ejaculates from different adult dogs were collected by digital manipulation. Seminal characteristics were evaluated in three different moments, fresh (T1), cooled (T2) and thawed (T3) semen for sperm motility and vigor, hypo-osmotic swelling test, sperm membrane integrity, sperm morphology, ultrastructural analysis and seminal pH. The samples were divided into two equal parts and each part was mixed with one extender type. After mixing, samples were packaged in 0,5mL French straws with 40 x 106 spermatozoa/straw. Semen samples were kept at 50C for 60 minutes (T2); then frozen in static vapor of nitrogen for the following 20 minutes and immersed in liquid nitrogen until being thawed in 700 C water for 8 seconds (T3). By analysis of variance, it would be possible to verify the animal effect on almost all variables observed in this study, except for sperm motility and membrane integrity. For cooled semen (T2), MP50 were significantly better for hypo-osmotic swelling test, sperm membrane integrity and pH (p<0,05) than Tris/Glycerol. For thawed semen (T3), there was no significant difference between extenders. By ultrastructural analysis, it was possible to verify swelling plasma and acrosomal sperm membranes in the different stages of freezing process. In conclusion, the extenders showed the same results as to morphofunctional characteristics the semen canine thawed.
22

Biochemical genetic typing of a Southern African endemic domestic dog breed from rural areas

Greyling, Letitia Maria 11 September 2008 (has links)
Electrophoresis (horizontal starch gel and PAGE) was used to study the genetic diversity and uniqueness of an endemic southern African domestic dog (Africanis) breed. The results were compared to those of three other populations/breeds: blood samples obtained from the Society for the Prevention of Cruelty to Animals (SPCA); indigenous Middle Eastern dog breed (the Saluqis) and hybrid (mongrel) dogs from the Jericho-area, near Brits (South Africa). Gene and phenotypic allele frequency and genetic differentiation were analysed at 21 protein coding loci. Nine polymorphic loci were identified (AK-1, -2, CK, PER, Hb, PA-1 to -3 and P-Tf). The average heterozygosity ranged from 0.106 to 0.159; the percentage of polymorphic loci were the least in the Saluqi (23.81%) and ranged to 33.33% in the Jericho breed; and the mean number of alleles per locus varied from 1.33 (Saluqi) to 1.43 (Jericho). Significant deviations (P<0.05) of allele frequencies from expected Hardy-Weinberg proportions occurred in loci AK-1, -2, Hb and P-Tf. These loci can serve as markers to define groups (i.e. only Africanis showed the presence of private alleles, CK*B and PA-2*C). The genetic distance values (D78) were between 0.001 and 0.026, with the smallest distance between Africanis and Saluqi, and the largest distance between Jericho and Africanis. This former, small D-value indicates a close genetic relationship between Africanis and Saluqis, supporting archaeological evidence that the endemic Africanis breed has indeed been introduced from the Middle East thousands of years ago, and not through western influences. These results are discussed with specific reference to genetic variation and differentiation that makes the endemic southern African domestic dog breed unique. / Prof. F.H. Van der Bank
23

Evaluation of epidural morphine and incisional bupivacaine for analgesia following hemilaminectomy in the dog

Horowitz, Farrah B. 23 June 2009 (has links)
A blind, placebo–controlled clinical trial was performed to evaluate the postoperative analgesic effect of topically administered, intraoperative, epidural morphine (Duramorph™) and intramuscular infiltration of the incision site with bupivacaine prior to closure of the skin in dogs undergoing hemilaminectomy for Hansen type I Intervertebral Disk Disease (IVDD). Thirty-three dogs were randomly allocated into four treatment groups: epidural Duramorph™ with incisional bupivacaine (DUR/BUP), epidural saline with incisional bupivacaine (SAL/BUP), epidural Duramorph™ with incisional saline (DUR/SAL), and epidural saline with incisional saline (SAL/SAL). All dogs were premedicated with a standard protocol and were anesthetized with propofol and isoflurane. After surgery, scores were assigned using a visual analog scale (VAS) for both pain and sedation and a composite pain scale (CPS). In addition, a von Frey anesthesiometer was used to determine pain thresholds at 1 cm and 3 cm from the surgical incision line (primary hyperalgesia) as well as on the lateral aspect of the stifle (secondary hyperalgesia). Assessments were carried out at fixed intervals over the 48 hour postoperative period. Significant differences were found between those groups treated with the epidural Duramorph™ and those that received epidural saline. Those dogs in the DUR/BUP and DUR/SAL groups exhibited lower von Frey pain thresholds and higher VAS and CPS scores than the SAL/BUP and SAL/SAL groups. The administration of bupivacaine had no significant effect on any measured outcome. The authors conclude that topically administered epidural Duramorph™ and intramuscular incisional bupivacaine do not enhance analgesia following hemilaminectomy in the dog. / Master of Science
24

History and consequence of keystone mammal eradication in the desert grasslands : the Arizona black-tailed prairie dog (Cynomys ludovicianus arizonensis) /

Oakes, Claudia Lea, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 366-391). Available also in a digital version from Dissertation Abstracts.
25

Feeding ecology and carrying capacity of a reintroduced pack of African wild dogs in a relatively small, fenced reserve.

Niemann, Sophie Mary. January 2010 (has links)
Reintroduction has been used successfully as a tool to restore declining populations of many threatened species. However, the lack of detailed evaluations of past reintroduction attempts has hindered a priori planning of management actions to achieve conservation goals. The metapopulation approach resulted in the most extensive and successful reintroduction efforts of the African wild dog (Lycaon pictus) in South Africa, but the approach was only recently evaluated by Gusset et al. (2008). For future reintroduction attempts to be successful on relatively small reserves, extensive evaluations are needed. Particular focus on feeding behaviour and impact on prey populations is essential to predict sustainability and carrying capacities in these areas for the African wild dog. A small reintroduced population of African wild dogs (pack number varying from 3 to 13 during the study period) were studied in the Karongwe Game reserve (79 km2) between January 2002 and January 2004. Fourteen prey species were identified: impala (Aepyceros melampus, 60 %) was the most dominant prey followed in descending order by bushbuck (Tragelaphus scriptus, 7.4 %), waterbuck (Kobus ellipsiprymnus, 4.9 %), warthog (Phacochoerus aethiopicus, 4.7 %), kudu (Tragelaphus strepsiceros, 4.4 %), and grey duiker (Sylvicapra grimmia, 4.4 %). Generally, prey were included in the diet in relation to abundance, and the dogs were not rate maximizing foragers but, unlike the findings of previous studies, were opportunistic feeders. The fences and angles in the fence, were used to assist hunting, but only for medium sized prey, impala and bushbuck, which were killed significantly more than expected along the fence line. A predictive prey preference model was then tested, but the model did not account for possible differences in feeding behaviours and prey preferences found in this, nor another study from the small Shambala Game Reserve. The model had limited accuracy as a predictive tool for proposed reintroductions into relatively small reserves. Models which can predict carrying capacity and minimum area requirements were also tested. Large variation and low numbers were predicted, which conflicted with social requirements needed for the survival of the population; further the models did not account for interspecific competition nor simultaneous depletion of prey by other guild predator. If the metapopulation approach is to continue to be successful and sustainable, more detailed evaluations of reintroductions of African wild dog on relatively small, fenced reserves are needed to determine the impact of these dogs on prey populations, and to determine if African wild dog feeding behaviour does differ for these areas in comparison to previously described open systems. With this information, more appropriate protocols regarding reintroduction and management can then be developed, thereby meeting one goal of management and conservation for the African wild dogs and their coexisting prey populations, and which can be used as a model for managing other large predators. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2010.
26

Establishing genetic and physiological baselines for the black-tailed prairie dog (Cynomys ludovicianus)

Biggs, Cindy Dawn. Beitinger, Thomas L., January 2007 (has links)
Thesis (Ph. D.)--University of North Texas, May, 2007. / Title from title page display. Includes bibliographical references.
27

Níveis de IgG anti-Leishmania e perfil de citocinas em cães machos e fêmeas assintomáticos naturalmente infectados por Leishmania (L.) Chagasi /

Dossi, Ana Cláudia Silva. January 2006 (has links)
Orientador: Valéria Marçal Felix de Lima / Banca: Rosangela Zacarias Machado / Banca: Alexandre Barbosa Reis / Resumo: O cão é o principal reservatório da Leishmania (Leishmania) chagasi, o parasita responsável pela Leishmaniose Visceral (LV) nas Américas. Na (LV) estudos em modelos experimentais, têm mostrado diferenças na resposta imunológica entre macho e fêmea. Na (L VC) tais estudos, não foram realizados. Este trabalho investigou em cães assintomáticos machos e fêmeas, naturalmente infectados por Leishmania (L.) chagasi, os níveis séricos de IgG contra antígenos totais de Leishmania, o nível de IL-10 e IFN-y, no sobrenadante do extrato do baço e fígado, e a citocina regulatória TGF-j3 no sobrenadante do extrato do baço e fígado, e sua produção natural no sobrenadante de cultura de células esplênicas. Os níveis de anticorpos anti-L. (L.) chagasi da classe IgG nos cães assintomáticos machos e fêmeas, não apresentaram diferença significativa entre o sexo. O nível de IL-10 mostrou-se elevado, no sobrenadante do extrato do fígado em cães infectados machos e fêmeas assintomáticos e apresentou dominância marcante em relação às outras citocinas. O nível do TGF-j3 mostrou-se aumentado no extrato do baço. O nível de IFN-y no baço dos grupos avaliados foi quantitativamente menor que as citocinas IL-10 e TGF-B. diferindo do observado no fígado onde foi observado uma baixa produção de TGF-j3 em relação ao IFN-y. No baço, o IFN-y apresentou diferença significativa em fêmeas assintomáticas quando comparadas com os machos assintomáticos. A observação da predominância das citocinas TGF-j3 no baço, e IL-10 no baço e fígado, em modelo ex vivo, sugere uma polarização da resposta imunológica para o padrão Th2 em cães naturalmente infectados por Leishmania (L.) chagasi. / Abstract: The dog is the main reservoir of Leíshmanía (Leíshmanía) chagasí, the parasite responsible for Visceral Leishmaniasis (VL) in the Americas. Experimental studies on VL have shown differences in the immune response of males and females. Such studies have not been carried out on canine visceral leishmaniasis. This study investigated the seric levei of IgG against Leíshmanía total antigens, the levels of IL-10 and IFN-y in the supernatant of spleen and liver extracts, the regulatory cytokine TGF-131 in the supernatant of spleen and liver extracts, and its natural production in the supernatant of spleen cell culture, in male and female asymptomatic dogs naturally infected by Leíshmanía (L.) chagasi. The levels of anti-L. (L.) chagasí IgG antibodies in male and female asymptomatic dogs did not differ significantly between the sexes. IL-10 levei was high in the supernatant of the liver extract of male and female asymptomatic infected dogs and predominated over the other cytokines. TGF-131 levei was increased in the spleen extract. The levei of IFN-y in the spleen of the group evaluated was quantitatively lower than the IL-10 and TGF-131 cytokine levels, different from what was observed in the liver, where a low productíon of TGF-131 was observed when compared to IFN-y. In the spleen, IFN-y presented a significant difference in the asymptomatic females when compared to the asymptomatic males. The observation of a predominance of TGF-131 cytokines in the spleen and of IL-10 in the spleen and liver of an ex vívo model suggests a polarization of the immune response towards the Th2 pattern in dogs naturally infected by Leíshmanía (L.) chagasí. / Mestre
28

Verifying parentage and gender of domestic dog conceptuses using microsatellites

Steckler, Daniela 21 December 2010 (has links)
Parentage testing in the domestic dog is finding increasing application for dog breed registries as well as in research. The aim of parentage verification is the correct assignment of both parents to the offspring. For accurate parentage verification informative microsatellite markers have to be identified. More powerful models to study artificial insemination in bitches will be possible if the paternity and gender of early dog conceptuses can be determined. The amelogenin gene locus has been used in bovine day six to day seven embryos for early gender determination but no research has been done on early conceptuses of the domestic dog. The aim of the current study was to establish an accurate method for parentage and gender determination from domestic dog conceptuses during early pregnancy in a multi-sire insemination trial. Semen from 10 male dogs was used in each of 12 females for artificial insemination. Blood and uterine tissue for DNA extraction was collected from males and females, and embryonic material was collected after ovariohysterectomy between 16 and 30 days after the onset of cytological dioestrus. Twenty-three microsatellite markers were used for parentage verification, and the amelogenin gene locus for gender determination. Mean observed heterozygosity, mean expected heterozygosity (HExp), and mean PIC were high (0.6753, 0.6785, and 0.628, respectively). There were 66 conceptuses. In two, neither parentage nor gender could be established because their tissue samples were contaminated. Parentage could be assigned by CERVUS 3.0.3 in 42 out of 64 of the cases (66%) without difficulty. Another 33% of the cases (21 out of 64) could be resolved using the number of exclusions, LOD scores or manual verification of genotyping errors. In one conceptus, paternity could not be established because its sire may have been either of two siblings. The gender of the female and male dogs was successfully confirmed using the amelogenin gene locus. The gender of the conceptuses was determined using the amelogenin gene locus (50% male, 50% female) but not confirmed by another method of gender determination such as karyotyping. As shown in the current study, the panel of 24 microsatellite markers used provides high information content suitable for parentage verification in multi-sire litters, as well as gender determination of early conceptuses. / Dissertation (MSc)--University of Pretoria, 2010. / Production Animal Studies / unrestricted
29

Ladra Seguro

Paniagua Palavicini , Gustavo Alonso 01 December 2019 (has links)
En el mundo de hoy tener una mascota es muy frecuente en todos los hogares. En Lima Metropolitana, 1.37 millones de hogares tiene alguna mascota en casa, esto representa el 55% de hogares limeños, y se estima que para el 2021 la cifra llegará a los 1.45 millones (Ipsos, 2016). Nuestra investigación nos permite conocer que las personas que tienen un perro, por lo general consideran al can como un miembro más del hogar, sin embargo el cuidado hacia las mascotas a veces no se puede dar por la falta de tiempo que presentan sus dueños y que incluso impide que puedan salir a pasear a sus mascotas por lo menos una vez al día. Por ello, si no ocurre esto los perros sufren, de estrés y de enfermedades somáticas que se desencadenan, además de problemas de conducta que a la larga acarrean problemas para los dueños y sus hogares (Mármol, 2016). Esta coyuntura da pie a que se cree “Ladra Seguro” proyecto que busca formalizar un servicio de paseadores de perros, apoyándose en herramientas tecnológicas de última generación como un aplicativo que brinde a los dueños de mascotas un servicio seguro y de buena calidad. Adicionalmente, se desarrollará un adiestramiento que permita a los caninos obtener todo el ejercicio y cuidado que requieran durante el tiempo que están fuera de su hogar. / In today's world, having a pet is very common in every home. In Metropolitan Lima, 1.37 million households have a pet at home, this represents 55% of Lima households, and it is estimated that by 2021 the figure will reach 1.45 million (Ipsos, 2016). Our research allows us to know that people who have a dog, generally consider the dog as another member of the household, however care for pets sometimes cannot be given due to the lack of time that their owners present and that they even prevent them from being able to walk their pets at least once a day. Therefore, if this does not happen, dogs suffer from stress and somatic diseases that are triggered, in addition to behavior problems that in the long run cause problems for the owners and their homes (Mármol, 2016). This situation gives rise to the creation of "Safe Barks", a project that seeks to formalize a service for dog walkers, relying on state-of-the-art technological tools such as an application that provides pet owners with a safe and good quality service. In addition, a training will be developed that allows the canines to obtain all the exercise and care they require during the time they are away from home. / Trabajo de investigación
30

An electrophysiological study of the effects of stimulation of left atrial receptors on efferent vagal nerve fibres

Walters, G. E. January 1986 (has links)
No description available.

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