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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.
41

Would you leave them behind? : disaster preparedness for live animals in museum collections /

Stokke, Michelle M. January 2007 (has links) (PDF)
Final Project (M.A.)--John F. Kennedy University, 2007. / "June 15, 2007"--T.p. Includes bibliographical references (p. 69-74).
42

Nosing behaviour in captive harbour seals (Phoca vitulina concolor) : implications for olfaction and affiliation /

Hanlan, Suzanne K., January 1998 (has links)
Thesis (M. Sc.), Memorial University of Newfoundland, 1999. / Bibliography: p. 169-179.
43

Autentiseringsmetoder i trådlösa nätverk : Jämförelse av autentiseringsportaler i öppna trådlösa nätverk

Modig, Dennis January 2011 (has links)
Trådlösa nätverk finns idag överallt och behovet av ständig internetaccess ökar för varje dag. Behovet av bra mjukvaror för att erbjuda säker trådlös internetaccess och samtidigt kunna ta betalt för det är ett problem. Denna rapport är en funktionsjämförelse av produkter som gör det möjligt att introducera spårbarhet och säkerhet för användarna i ett trådlöst nätverk. Mikrotik RouterOS jämfördes emot Zeroshell där funktionaliteten sedan sattes i en verklighetsbaserad kontext och möjliga implementationer presenterades. Resultatet påvisade att Mikrotik RouterOS passade bättre för de flesta scenarier än exempelvis Zeroshell. Men att Zeroshell istället har mycket bra stöd för katalogtjänster.
44

Time- and Dose-related Effects of a Gonadotropin-releasing Hormone Agonist and Dopamine Antagonist on Reproduction in the Northern Leopard Frog (Lithobates pipiens) and the Western Clawed Frog (Silurana tropicalis)

Vu, Maria January 2017 (has links)
The recent decline and disappearance of many amphibians around the world is thought to be the sign of an impending sixth mass extinction that is driven by disease, habitat loss and pollution. Reproductive technologies are now required to establish captive colonies followed by reintroduction into suitable habitats. The AMPHIPLEX method is a hormone mixture that has successfully stimulated spawning in several amphibians. However, its extensive application requires further experimentation and knowledge regarding the basic neuroendocrine control of reproduction in amphibians. The role of the catecholamine neurotransmitter dopamine in the regulation of spawning and gonadotropin synthesis was investigated using multiple time- and dose-related approaches in the field and laboratory. These end points were explored in two distantly-related frog species: the Northern leopard frog (Lithobates pipiens) and the Western clawed frog (Silurana tropicalis). Northern leopard frogs were injected during the natural breeding season with three doses of a gonadotropin-releasing hormone agonist (GnRH-A) (0.1 μg/g , 0.2 μg/g and 0.4 μg/g) alone and in combination with two doses of the selective dopamine receptor D2 antagonist metoclopramide (MET) (5 μg/g and 10 μg/g). Injected animals were allowed to breed in mesocosms in an outdoor field. Time to amplexus and oviposition were assessed, and egg mass release, incidences of amplexus, egg mass weight, total egg numbers and fertilization rates were measured. The results revealed no statistically significant interaction between GnRH-A and MET on amplexus and oviposition. A series of GnRH-A dose-response spawning studies were conducted in the Western clawed frog. The current findings indicate that partial ovulation, male sexual behavior and fertilization can be induced by 4 μg/g of GnRH-A alone and in combination with 10 μg/g of MET. This represents a first step towards understanding basic neuroendocrine reproductive mechanisms in this species. These spawning results were paired with a second end point which explored the molecular mechanisms of gonadotropin synthesis in response to GnRH-A and MET alone and in combination. Pituitary gene expression results in the Northern leopard frog indicate a potentiating action of MET when combined with GnRH-A on the mRNA levels of gonadotropin subunits 36 hours following injection. The postulated mechanisms of action are through the upregulation of gonadotropin-releasing hormone receptor 1 and the downregulation of dopamine receptor D2. Such gene expression pathways were similarly explored in the Western clawed frog, however no significant changes in pituitary gonadotropin and receptor gene expression were present at 12 hours post-injection. The hypothesized inhibitory action of dopamine was supported by pituitary gene expression analysis, but not by spawning outcome. The results from this study provide a fundamental framework for future time- and dose-response investigations to improve current spawning methods in amphibians.
45

The Captive Animal Activity Tracking System: A Systematic Method for the Continuous Evaluation of Captive Animal Welfare.

Kalafut, Kathryn Lynn 12 1900 (has links)
Optimal animal welfare has been a long-term goal for captive animal institutions. To measure welfare a definition and identification of elements that make up welfare need to be established. Further, a method to measure welfare's elements that can be implemented into staff's daily routine is necessary to establish baseline levels and track changes in welfare. The goal of the proposed captive animal activity tracking system is to allow for the measurement of each element of welfare quickly, while providing information regarding the animal's current state of welfare and how changes to the animal's environment affect welfare. The data show that this system is effective in revealing behavioral patterns and changes in behavior that occurred in response to environmental changes.
46

Breeding behavior of captive emperor penguins (Aptenodytes forsteri)

Kiel, Mary Elizabeth 01 January 1983 (has links)
Breeding behavior of captive Emperor Penguins (Aptenodytes forsteri) was observed at Sea World, San Diego, California during July, August, and September 1980, and April 1981. Emphasis was on displays, courtship, egg-laying, incubation, and care of chicks. I observed the trumpet display most often between birds of opposite sexes and I interpret it as a signal of sexual identity. I interpreted the sideways stare display as a signal of sexual identity important in pair bond maintenance. Three head movements studied shared several functions including comfort behavior and reduction of intraspecific aggression. My observations confirmed that the display walk occurs in Emperors and is used by males to attract females. The single note cry allows separated members of a pair to find each other. Results of an attempt to sex Emperor Penguins by vocalization are reported.
47

Genetic admixture, inbreeding and heritability estimates in captive African cheetahs (Acinonyx jubatus) including linkage analysis for the King cheetah phenotype

Sasidharan-Priyadersini, Sooryakanth 26 May 2013 (has links)
This multifaceted study primarily aimed at understanding the genetic make-up of captive versus wild cheetah (Acinonyx jubatus) populations in South Africa, with a specific emphasis on a valuable gene pool of a recessive phenotype that is increasingly being maintained in captive population country-wide. The current literature on cheetah genetics has very little information on diversity levels of wild South African cheetahs, and no information on founder dynamics and genetic make-up of South African captive populations. Decisions on cheetah relocations are being made, implementing current conservation policy, from assumptions on origin and relatedness. This research compared population genetic parameters within the largest South African captive cheetah population to free-ranging Namibian and South African conspecifics. The study addressed concerns regarding excessive Namibian genetic introgression into the native captive population and established the extent of genetic variability and Namibian ancestry within the captive population. The study has attempted to address the rising concern among conservation officials with respect to illegal trade of wild-captured cheetahs, wild caught cheetahs that are sold as captive-bred after implanting a microchip. In addition to establishing routine parentage verification using genetic markers that are polymorphic in this species, this study established a technique powerful enough to estimate ancestry in cheetahs of unknown antecedents. The potential of spatial Bayesian clustering to differentiate the point of origin of unknown cheetahs was exploited and in addition, a database for future forensic efforts to address the problem of illegal trade was established. The captive population that was part of this dataset proved to be quite admixed, excepting for the King lineage which was distinct. The second aspect of this study investigated complex conditions such as development of gastritis, renal conditions and/or susceptibility to infections and its relation to pedigree and marker based inbreeding levels. Heritability values for important breeding traits were estimated from pedigree records of 532 cheetahs and are reported for the first time. Gastritis was weakly correlated to the expression of the King trait. Finally, a smaller cohort of the captive pedigree that segregates for a recessive colour variant called the King phenotype was tested for the assumption that the variation is a mutation of the tabby locus described in domestic cats. Genetic linkage analysis was done by testing microsatellite markers detected linked to Tabby for linkage to a conserved region in the cheetah that potentially codes for the King coat colour. Genetic linkage analysis was not detected between the King locus and the domestic cat microsatellite markers used for this study, with LOD scores remaining non-significant for all the markers. / Thesis (PhD)--University of Pretoria, 2011. / Production Animal Studies / unrestricted
48

Genetic Assessment of Native and Non-Native White-Tailed Deer (Odocoileus Virginianus) in the Southcentral U.S.

Youngmann, Jordan L 14 December 2018 (has links)
Population genetics of white-tailed deer (Odocoileus virginianus) have been influenced through human actions including the translocation of deer from across the United States in the 1900s and, recently, the creation of the captive-cervid industry, which uses animal husbandry to manipulate genetic variation. To assess the effects of these actions, I studied the genetic variation of free-range and captive populations of deer across the southcentral U.S. using a 14 microsatellite panel. In free-range populations I found genetic structure that divided deer west to east along the Mississippi River. Additionally, I found that captive populations were genetically distinct from geographically proximate free-range populations. However, after 2 generations of hybridization, this distinction disappeared. Finally, using both Bayesian clustering and multivariate approaches, I was able to identify a non-native individual from local free-range populations in southern Mississippi. Using these methods, wildlife managers can further investigate cases of hybridization between non-native deer and free-range populations.
49

Determination of linkage and degree of relatedness in a captive population of American kestrels using DNA fingerprinting

Cunningham, Heather V. January 1995 (has links)
No description available.
50

PRIMATE SUPER-GROUPS? POLYSPECIFIC ASSOCIATIONS OF CAPTIVE MONKEYS

Russak, Samantha 27 April 2006 (has links)
No description available.

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