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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.
751

[PETWALK] / [PETWALK]

Blanc Arias, Dan, Cruz Rojas, Nidia, Sánchez Huamán, Carolina, Ushiñahua Meza, Maria Fernanda, Zavala Huaytan, Kevin Omar 31 July 2020 (has links)
En la actualidad, todos los seres humanos utilizan dispositivos móviles. Con el pasar del tiempo, las personas utilizan los diversos servicios que éstos ofrecen. Entre sus principales atributos están las aplicaciones móviles (“Apps”) / y se han vuelto parte esencial de la vida. Por otro lado, los animales domésticos, especialmente los perros, han pasado de ser mascotas a miembros importantes en los hogares. Las familias reconocen su influencia positiva en lo psicológico y social. En el presente trabajo se busca determinar la viabilidad de un servicio que mezcla la tecnología que ofrecen los dispositivos móviles con las necesidades de los perros y a su vez de sus dueños, es decir, los paseos. Este proyecto pretende ofrecer una aplicación móvil que facilitará la conexión entre los dueños de mascotas y paseadores capacitados, seleccionando el horario, seguimiento en tiempo real y cuidados especiales en caso se necesite. Para ello se ha realizado un proceso de ideación, desarrollo de modelo de negocio, considerando la descripción del problema a solucionar del usuario, y la determinación del segmento objetivo. Además, se diseñó experimentos que permitan validar el modelo de negocio, las estrategias para la ejecución del concierge y las proyecciones de ventas. Una vez consolidada toda la información mencionada anteriormente, se desarrolló planes que requiere el negocio, los cuales son: Estratégico, Operativo, Recursos Humanos, Marketing, Responsabilidad Social Empresarial, Financiero y Financiamiento. Por último, se hallarán las conclusiones del trabajo y el resultado potencial que tendría el negocio una vez sea implementado.
752

Conservation genetics of African wild dogs Lycaon pictus (Temminck, 1820) in South Africa

Edwards, Janet Marguerite 12 November 2010 (has links)
The African wild dog Lycaon pictus is Africa’s second most endangered carnivore. Only 14 out of 39 countries in Africa still have wild dogs present. This makes the populations of wild dogs in South Africa very valuable with respect to the entire species. Kruger National Park (Kruger) has the only self-sustaining and viable population of wild dogs in South Africa, making Kruger the core area of conservation for South African wild dogs. It is of vital importance to know the numbers of wild dogs present in Kruger. In chapter 2 of this dissertation I monitored and gathered demographic information from as many southern Kruger wild dog packs and individuals as possible over a three month period. I used real time text messaging to collect the information. A wild dog hotline number was used for tourists to contact immediately after they sighted a pack, noting location, time and number of wild dogs sighted. This new technique resulted in more than 300 reported wild dog sightings in three months enabling a count of individuals and packs. This also created an opportunity to take identification photographs and to collect DNA samples. In 1997 it was decided to establish and manage several small wild dog populations in various geographically isolated reserves in South Africa as one large managed metapopulation. In order to simulate the natural dispersal patterns of wild dogs, individuals are translocated between the managed metapopulation reserves, imitating natural gene flow and hopefully preventing inbreeding. To date, all decisions have been made using demographic data only. This in time is likely to result in a loss of genetic diversity and subsequent inbreeding. The aim of chapter 3 was to obtain genetic information from wild dogs in the managed metapopulation and Kruger (chapter 2) to provide a basis for sound population management including monitoring of inbreeding and maintaining levels of genetic diversity similar to those found in large self-sustaining populations (such as Kruger). This study included both mitochondrial DNA (mtDNA) and nuclear microsatellite loci to determine the genetic structure of South Africa’s wild dogs specifically with regards to genetic diversity, population structure and relatedness. The results showed a difference in historical and recent diversity between the managed metapopulation and Kruger. Two genetic clusters were evident in South Africa, however one was due to wild dogs from Botswana being translocated into the managed metapopulation. After the Botswana influence was removed from the analysis, three genetic clusters were observed in the South African wild dogs. These three genetic clusters comprise too few wild dogs to manage them as separate units. Relatedness between and within populations, reserves and packs were estimated and can in future be used to guide translocations of wild dogs to maximise their genetic variability. It is suggested that due to the low numbers, and historical and recent trends in genetic structure of South Africa’s wild dogs, they should be managed as one unit, allowing movements to and from neighbouring countries. All translocations should follow an isolation-by-distance pattern. / Dissertation (MSc)--University of Pretoria, 2010. / Animal and Wildlife Sciences / unrestricted
753

The effects of two formulations of deslorelin on the reproduction of male African wild dogs (Lycaon pictus)

Newell-Fugate, Annie Elizabeth 19 February 2009 (has links)
The African wild dog (Lycaon pictus) is the second most endangered carnivore in Africa. Although several high-profile endangered species are imperiled due to poor fertility, inadequate genetic diversity, and a reliance on specific niches, the wild dog is threatened by decreasing land space and human hunting practices. Wild dogs are highly fertile with an average litter size of nine at De Wildt Cheetah and Wildlife Centre. Wild dog males have 3 million to 900 million sperm per ejaculate and 45-75% progressive motility during the breeding season. Wild dogs released into small nature reserves in South Africa experience increased survival rates due to sizeable litters, abundant prey, and increased hunting success along fence lines. Furthermore, the current demand for captive-bred wild dogs is low due to lack of demand by overseas zoos and the inability of nature reserves to accommodate more dogs. Long-acting GnRH analogues have been used for fertility control in many wildlife species. However, dosing and efficacy differ among species and individual animals. This study assessed the efficacy of the GnRH analogue, deslorelin, on reproductive parameters of male African wild dogs. Seasonal effects on reproduction were also evaluated. Captive male African wild dogs housed at the De Wildt Cheetah and Wildlife Centre were administered either a 4.7 mg deslorelin implant (Suprelorin,® Peptech Animal Health (Pty) Ltd, Sydney, Australia; n = 10), an experimental 9.4 mg deslorelin injection (n = 11) or a placebo injection (n = 6). Treatment was administered during the non-breeding season (Month 0), and dogs were assessed at Months 3, 5, 6, and 7. Reproductive parameters evaluated before and after treatment included: serum testosterone, testicular and prostatic volume, and semen quality. Serum testosterone was assessed with a previously validated double antibody DSL testosterone radioimmunoassay kit (Diagnostic Systems Laboratories, Inc, Webster, TX). Testicular volume was calculated from testicular dimensions measured with a calliper and prostatic volume from dimensions obtained by trans-cutaneous ultrasound. Data were analyzed with ANOVA. Although the 4.7 mg deslorelin implant was safe for use in male wild dogs, there was wide variation in efficacy among dogs. The serum testosterone of implant dogs did not decrease to baseline after treatment and only half the dogs administered an implant became azoospermic post-treatment. The experimental long-acting deslorelin injection was ineffective for contraception of male African wild dogs. All three groups of dogs experienced an improvement in reproductive parameters during the months of February through May, the rainy season in northern South Africa and the period during which female African wild dogs enter oestrus, suggesting that a breeding season not only exists in the female African dog but also in the male. Testis and prostatic volume increased, serum testosterone concentrations and semen quality improved during that time of year. Further studies of deslorelin in male wild dogs are warranted to determine the appropriate dose, pay-out pattern, delivery method, and season of delivery necessary for adequate contraception in this species. / Dissertation (MSc)--University of Pretoria, 2008. / Production Animal Studies / unrestricted
754

Genetic verification of multiple paternity in two free-ranging isolated populations of African wild dogs (Lycaon pictus)

Moueix, Charlotte Henriette Marie 04 May 2007 (has links)
The African wild dog, second most endangered carnivore in Africa, has a well-developed, highly cooperative pack system. The usual structure of a pack consists of a dominant breeding pair, the alpha male and female, several subordinates, non-breeding adults and dependent offspring. Domestic dog microsatellites were used to study the parentage in three packs and confirm that more than one dog, including the subordinate males, can sire pups within a litter as previously suggested. The study was performed on two isolated populations of wild dogs in the North West Province of South Africa. In Madikwe Game Reserve, skin samples from 47 dogs were obtained by means of biopsy darts (adults) and skin slivers taken from the ear (subadults) and stored in absolute ethanol. In Pilanesberg National Park, blood samples from 18 captured dogs were collected in EDTA blood tubes. The wild dogs were photographed and individually identified according to coat patterns. Behavioural data to determine ranking were collected from all three packs. DNA was extracted from collected samples using proteinase-K digestion followed by isolation of DNA with phenol/chloroform/isoamyl alcohol. A total of 16 microsatellite loci that consistently amplified and appeared to be polymorphic in wild dogs, were used. Polymerase Chain Reaction (PCR) was performed using two panels of microsatellite loci in multiplex reactions. An amount of 1 µl of PCR product was loaded on to the 3130 XL Genetic Analyser with Genescan 500 LIZ (Applied Biosystems) size standard and analysed using STRand (Board of Regents, University of California) software program. CERVUS 2.0 software was used to calculate allele frequencies, expected and observed heterozygosity, frequency of null alleles, polymorphic information content and exclusion probabilities for parentage assignment. Parentage verification was also performed manually. The parentage analysis revealed that at least one pup was not sired by the alpha male in each of the five litters studied. Although previous studies suggested that the alpha male sires the majority of offspring in the pack, our results confirm that subordinate males commonly sire pups with the alpha female if and when the opportunity arises. This is possibly a mechanism to decrease the effects of inbreeding. / Dissertation (MSc (Veterinary Sciences))--University of Pretoria, 2006. / Production Animal Studies / unrestricted
755

Analysis of domestic dog mitochondrial DNA sequence variation for forensic investigations

Angleby, Helen January 2005 (has links)
The first method for DNA analysis in forensics was presented in 1985. Since then, the introduction of the polymerase chain reaction (PCR) has rendered possible the analysis of small amounts of DNA and automated sequencing and fragment analysis techniques have facilitated the analyses. In most cases short tandemly repeated regions (STRs) of nuclear DNA are analysed in forensic investigations, but all samples cannot be successfully analysed using this method. For samples containing minute amounts of DNA or degraded DNA, such as shed hairs, analysis of mitochondrial DNA (mtDNA) is generally more successful due to the presence of thousands of copies of mtDNA molecules per cell. In Sweden, ~40 % of all households have cats or dogs. With ~9 million humans shedding ~100 scalp hairs per day, and ~1.6 million cats and ~1 million dogs shedding hairs it is not surprising that shed hairs are one of the most common biological evidence found at crime scenes. However, the match probability for domestic dog mtDNA analysis has only been investigated in a few minor studies. Furthermore, although breed –sequence correlations of the noncoding mtDNA control region (CR) have been analysed in a few studies, showing limited correlations, no largescale studies have been performed previously. Thus, there have not been any comprehensive studies of forensic informativity of dog mtDNA. In the two papers presented in this thesis we have tried to lay a foundation for forensic use of analysis of domestic dog mtDNA. In the first paper, CR sequences were analysed and the exclusion capacity was investigated for a number of different populations. This is also the first comprehensive study of the correlation between mtDNA CR type and breed, type, and geographic origin of domestic dogs. Since the exclusion capacity for analysis of domestic dog CR sequences is relatively low, it was investigated in the second paper to what extent the discrimination power is improved by analysis of coding sequence. The exclusion capacity improved considerably when 3,000 base pairs of coding sequences where analysed in addition to CR sequences. This study will hopefully work as a basis for future development of analysis of dog mtDNA for forensic purposes. / QC 20101123
756

The Use of Enhanced Milieu Teaching and Animal-Assisted Therapy to Increase Utterance Length and Frequency in an Autistic Child

Witt, Aaron 18 May 2022 (has links)
No description available.
757

Sonographische Untersuchung und Dickenmessung des weichen Gaumens beim Hund

Köhler, Claudia 20 May 2014 (has links)
In der Veterinärmedizin existieren nur wenige Veröffentlichungen zur, in der Humanmedizin weitgehend etablierten, Sonographie des Oropharynx. Da vor allem bei brachyzephalen Hunden das Ausmaß der Hyperplasie der oropharyngalen Weichteile, insbesondere des weichen Gaumens, von großem diagnostischen Interesse ist, wird nach Möglichkeiten zur wenig invasiven Untersuchung dieser Region am wachen Patienten gesucht. So war es Ziel dieser kumulativen Dissertation die Grundlagen der sonographischen Untersuchungs- und Messmethode am weichen Gaumen zu erarbeiten. Die Darstellung der sonographischen Anatomie des weichen Gaumens und der Umgebung erfolgte in der ersten Studie an sieben Tierkörpern normozephaler Hunderassen. Die transkutane Untersuchung erfolgte bei submentaler Schallkopfauflage. Zudem kamen speziell geformte Schallköpfe zur direkten Auflage auf den weichen Gaumen in einer intraoralen Untersuchung zum Einsatz. Zur Erleichterung der Identifizierung der anatomischen Strukturen wurden Wasserbad- und sequentielle Ultraschalluntersuchungen im Anschluss an submentale Weichteilpräparationen des Maulhöhlenbodens durchgeführt. Unter Herstellung des Gewebekontaktes zwischen Zunge und weichem Gaumens bei submentaler Schallkopfauflage, gelang die transkutane sonographische Darstellung des weichen Gaumens im kranialen und mittleren Bereich. Der weiche Gaumen wies eine mondsichelähnliche Form und eine geringe Echogenität auf. Als charakteristisch zeigte sich der Übergang von hartem zu weichem Gaumen, die Darstellung des kaudalen Anteils des Gaumensegels ist aufgrund der umgebenen Luft und Überlagerung mit dem Zungenbein nur eingeschränkt möglich. Die intraorale Untersuchung erlaubte die Darstellung der gaumenspezifischen Echotextur. In der zweiten Studie wurde an 15 normozephalen Hunden in Allgemeinanästhesie die Dicke der Gaumensegel sowohl sonographisch als auch computertomographisch an zwei definierten Messpunkten bestimmt. Die Übereinstimmung der Ergebnisse von wiederholten Messungen mit der jeweiligen Messmethode wurde geprüft. Die wiederholten Messungen erzielten sehr gute Übereinstimmungen (Mean absolute deviation von 0), so dass davon ausgegangen werden kann, dass sowohl die Sonographie als auch die CT reproduzierbare Messungen ermöglicht. Im Messmethodenvergleich wurden die Messergebnisse, die mit den unterschiedlichen Messverfahren (Ultraschall und CT) gewonnen wurden, in der Bland-Altman Auswertung miteinander verglichen. Es waren Abweichungen für beide Messpunkte zu verzeichnen, wobei der Mittelwert der Abweichung vor allem für den zweiten Messpunkt mit 0,31 cm als hoch anzusehen ist. Der Mittelwert der Abweichung fällt am ersten Messpunkt mit 0,08 cm geringer aus. Die klinisch relevanten Abweichungen wurden als Folge der zwischen beiden Messmethoden variierenden Untersuchungsbedingungen, insbesondere der abweichenden Patientenlagerung, interpretiert. Sonographie und CT sind damit, trotz guter Reliabilität des einzelnen Verfahrens, als nicht austauschbare Methoden zur Gaumensegeldickenmessung anzusehen. Die transkutane Sonographie ermöglichte, unter den geschilderten Untersuchungs-bedingungen, erstmals eine Darstellung des kranialen und mittleren Anteils des weichen Gaumens. Der kaudale Anteil des Gaumensegels konnte nicht identifiziert werden. Die Sonographie birgt, nach Ermittlung entsprechender Referenzbereiche, das Potential einer nichtinvasiven, schnellen Untersuchungsmethode zur Vermessung der Gaumensegeldicke am wachen Hund.
758

Effects of caretaker interactions on dog welfare in commercial breeding (CB) kennels

Joanna C Rogowski (12476757) 28 April 2022 (has links)
<p>  </p> <p>A large portion of the demand for purebred dogs in the United States is met by commercial breeding (CB). CB is a contentious issue, and concern exists surrounding the quality and quantity of human-animal interactions in CB kennels. Quality of caretaker interactions has been demonstrated to affect welfare in livestock and laboratory animals, yet is widely understudied in kenneled dogs, especially those kept for CB. It therefore warrants investigation. Thus, the aim of this study was to determine the effect of a short, regular, positive caretaker interaction on physiological and behavioral metrics of dog welfare in CB kennels. Adult bitches (n = 47) from two CB kennels received a daily interaction with a familiar caretaker for two weeks. Half of the dogs (n = 24) received a 2-minute caretaker interaction with treats (CI), and the other half (n = 23) received treats only (TO). All other human interactions were limited to routine husbandry. Fecal secretory immunoglobulin A (sIgA), hair cortisol concentration (HCC), and behavior in response to human approach were measured at baseline (Day 0), after two weeks of treatment (Day 14), and two weeks after treatment ended (Day 28). Behavior during treatment delivery was scored from video on days 1, 2, 8, 9, 13, and 14. General linear mixed models were used with treatment type and timepoint as fixed effects, dog nested within pen as random effects, and welfare metrics as dependent variables. Data from both facilities were analyzed and presented separately. In Facility 1 (n = 25), treatment type did not affect hair cortisol concentration (HCC) or fecal secretory immunoglobulin A (sIgA). However, HCC increased significantly from Day 0 to Day 28 (X2 = 5.83, <em>p </em>= 0.016) and fecal sIgA decreased significantly (X2 = 21.52, <em>p </em>< 0.001) over all three timepoints. Affiliative behavior in response to human approach increased over time with no significant effect of treatment type or tester (X2=10.549, <em>p</em>=0.001). Additionally, time spent in proximity to the caretaker significantly increased in both treatment groups during the daily interaction (CI: X2=14.047, <em>p</em><0.001, and TO: X2=5.121, <em>p</em>=0.024). In Facility 2 (n = 22), there was no effect of treatment type on physiological metrics, however, HCC decreased in time (X2 = 6.66, <em>p </em>= 0.009) in both treatment groups combined. Affiliative response to human approach increased over time in Facility 2 (X2=13.5782, <em>p</em>=0.001). During daily interactions, dogs from the TO group displayed increased affiliative (X2 = 8.58, <em>p </em>= 0.003) and decreased ambivalent (X2 = 10.42, <em>p </em>= 0.001) behaviors over time, while dogs from the CI group showed increasing latency to approach the caretaker (X2 = 4.38, <em>p </em>= 0.033). Changes in physiological and behavioral metrics differed by facility and treatment group. Factors such as variation in treatment quality and prior caretaker-animal relationship may play a role in dogs’ responses to the treatment. These results suggest that a caretaker interaction has the potential to improve welfare in dogs residing in CB kennels. However, careful consideration must be taken when implementing new protocols to avoid unintended increases in stress. For some adult dogs unaccustomed to extended, structured interactions with their caretakers, a 2-minute session may have resulted in increased physiological and behavioral stress, suggesting that a longer interaction might have jeopardized rather than improved their welfare. For these dogs, a more gradual introduction to human interactions may be more beneficial. This study offers new insight on the implementation of socialization, counterconditioning, and caretaker-dog interaction practices to maximize positive welfare in CB kennels. Future research is needed to further validate and expand upon these findings.</p>
759

Shape Change and Variation in the Cranial Morphology of Wild Canids (Canis lupus, Canis latrans, Canis rufus) Compared to Domestic Dogs (Canis familiaris) Using Geometric Morphometrics

Schmitt, E., Wallace, S. 01 January 2014 (has links)
Wild canid populations exhibit different anatomical morphologies compared to domesticated dogs in North America. This is particularly important concerning archaeological sites, which may contain early domesticated species, for the proper identification of osteological remains. Previous studies have indicated domestic dogs exhibit a shorter rostrum accompanied by a crowded tooth row; however, none describe the overall complexity of these changes. Consequently, using a landmark-based geometric morphometric analysis, cranial morphological characteristics were examined in North American wild canids: the gray wolf (Canis lupus), coyote (Canis latrans), red wolf (Canis rufus), and the domestic dog (Canis familiaris). The shape and size of the cranium in lateral and ventral views were compared between the three wild species to the group of domesticated dogs. Wild canids clustered separately from the domestic group in all statistical analyses. Results indicate an expansion of the orbital region, a compression of the rostrum, and an overall warping in the shape and orientation of the skull. In domestic species, there is also a downward shift in the frontal portion of the skull accompanied by the braincase assuming a more upward position. This technique successfully depicted how slight changes in isolated areas of the cranium can have an impact on the overall shape and morphology of the skull. We presume these changes in cranial anatomy reflect the recent selective pressures domestic dogs have undergone since diverging from their wild ancestors.
760

Microvasculature of the Urinary Bladder of the Dog: A Study Using Vascular Corrosion Casting

Hossler, Fred E., Kao, Race L. 01 June 2007 (has links)
The urinary bladder is an unusual organ in that its normal function includes filling and emptying with alternating changes in internal pressure. Although fluctuations in blood flow to the bladder wall are known to accompany these changes, detailed descriptions of the bladder microvasculature are sparse. The present study uses vascular corrosion casting and scanning electron microscopy to describe the three-dimensional anatomy of the microvasculature of the urinary bladder of the dog. Specialized features of that microvasculature, including collateral circulation, vessel folding, vessel orientation, the presence of valves and sphincters, and mucosal capillary density, that may enhance and control blood flow during normal bladder function, are described and discussed.

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