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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.
61

Refining and Validating an on-site Canine Welfare Assessment Tool Developed for use in Commercial Breeding Kennels.

Lynda W. Mugenda (5930759) 17 January 2019 (has links)
<p>Accurate assessments of behavior and welfare are needed to evaluate the state of domestic dogs maintained in commercial breeding (CB) and other types of kennels. Field assessments of dogs’ states of being must be reliable, valid and efficient. However, observer subjectivity and situational variation in dogs’ responses pose a challenge to incorporating behavioral metrics into welfare assessment tools. The published Field Instantaneous Dog Observation (FIDO) tool, designed to capture the immediately observable physical and behavioral status of dogs in kennels, was thus evaluated on its reliability and validity. Specifically, the main goals were to determine 1) reliability of the behavioral scoring when used by novice raters, 2) whether and to what extent dogs’ behavioral responses to stranger-approach changed during a 30-second observation period, and 3) the predictive power of the FIDO scoring on behavioral responses of dogs placed within a standardized arena with a stranger. Behavioral responses to stranger-approach were organized into three categories: red, indicating a fearful response to approach, green, indicating an affiliative or neutral response, and yellow, indicating an ambivalent response. In study one, behavior assessment was conducted by two novice raters with 50 dogs housed at two US shelters. A stranger approached the home pen of each dog in a non-threatening manner, stood quietly, extended a hand to the dog and scored the response while the test was video-recorded. Intra-rater reliability was assessed by comparing each rater’s live observation scores with their scores of the same dogs using video recordings. Inter-rater agreement between scores from video recordings was also calculated. In study two, 81 commercial breeding dogs maintained at four USDA-licensed CB facilities in the US were approached by one observer and scored once every five seconds for 30 seconds. Of the 81 subject dogs, 56 met the criteria for full sampling. In study three, 40 pairs of dogs were scored using the FIDO tool in their home pens at four USDA-licensed CB facilities and assessed on responses to an unfamiliar observer in a field test conducted in an outdoor arena. Behavioral measures from the field test such as latencies to approach the stranger and durations in different areas of the arena were captured from video recordings and subjected to a principal components analysis [PCA] for reduction of variables. A multivariate multiple regression analysis was thereafter used, with principal component scores obtained from the PCA as outcome variables, and FIDO scores as predictor variables, accounting for other factors such as breed and group composition. Results from study one indicated that raters showed almost perfect agreement between their own scores of live and video-recorded shelter dog responses (kappa = 0.83, 0.89) and between each other’s video-recorded scores (kappa = 0.87), indicating high intra- and inter-rater reliability. Results from study two indicated that over a 30-second time frame with five-second increments, 91% of the dogs showed no change in their behavioral response to approach. This suggests that the first five seconds of scoring provide a reliable time point for assessing behavior using the FIDO tool and indicates no benefit to extending the FIDO scoring period to gauge dogs’ immediate responses to stranger-approach. Results from study three showed that dogs scored as red, as determined by the FIDO scoring, also showed higher scores associated with avoidance, indicated by greater time spent away and more time taken to approach the unfamiliar person in the field test (p = 0.039). FIDO scoring was, however, not significantly predictive of other behavioral responses such as interaction with the unfamiliar person. How dogs were housed was also significantly associated with incidences of escape attempts from the arena; dogs paired as a mixed sex (i.e. male-female) showed lower scores on incidences of escape attempts than dogs paired as a same sex (i.e. female-female) (p = 0.003). Taken together, these results suggest that the FIDO tool can be used by individuals without much expertise in canine behavior, and also attest to the practicality of the tool via a reliable five-second approach. Further, results also indicate that the FIDO scoring can help to identify fearful dogs in need of greater socialization towards unfamiliar people. Future research would, however, be valuable in validating behavioral scores obtained using the tool against long-term indicators of overall welfare.</p>
62

Investigating the behaviour and welfare of captive flamingos (Phoenicopterformes)

Rose, Paul Edward January 2018 (has links)
When a species is housed in captivity there are facets of the managed environment that can impact on individual and population welfare. A key component of an individual’s environment is its social environment, which can have important implications for animal health and welfare. Highly social species may experience impoverished welfare if kept in captive groups that differ in size, structure and demographic to that experienced by free-living animals. Amongst the most common of social animals to be housed in captivity are the flamingos (Phoenicopteridae). The unique evolutionary biology of these birds means that key aspects of their behaviour depends upon group living. A positive relationship between breeding success and increasing flock size has previously been noted, but how flamingo flocks are structured socially remains mysterious. All six species of flamingo are currently found in captive collections. The three more generalist species, greater (Phoenicopterus roseus), Caribbean (P. ruber) and Chilean (P. chilensis) flamingos are found commonly in zoos and can, under the right conditions, breed well. The other flamingo species are much more specialised in their habitat and dietary requirements and have proved more challenging with regards to their captive management. These three species are the Andean (Phoenicoparrus andinus), James’ (P. jamesi) and lesser (Phoeniconaias minor) flamingos. All six species are included in the experimental work presented in this thesis. This research aimed to evaluate specific elements of flamingo group living using social network analysis (SNA). It also aimed to assess influences of the captive environment (i.e. enclosure style and visitor number) and climate on enclosure usage, time-activity budgets and behavioural diversity to provide, as far as possible, a complete insight into how to measure, assess and evaluate captive flamingo welfare. A synthesis of the relevance of SNA to zoo animal management, and a review of current literature to identify research needs that could evidence good flamingo husbandry form the basis of the first two chapters. These two overview chapters support the questions asked in the following data-based sections of the thesis. Flamingos were observed at WWT Slimbridge Wetland Centre from March 2012 to July 2016 with data on patterns of social associations being collected four times daily (depending upon weather and bird husbandry). Associations were defined as birds within one neck length of each other and, using photos, the affiliations of each bird in the group were recorded. For assessment of bond strength, network position and identification of preferred/avoided partners a Half-Weight Index was applied to these data. Permutation testing was applied to association matrices to determine the difference between the number of observed preferential bonds (and avoided bonds) and Mantel tests were used to compare matrix correlations to assess differences between seasons, species, years and enclosures (where appropriate). The SNA programmes Socprog, UCInet and Netdraw were used to analyse network data. These network data form the basis of three chapters and show that flamingos associate preferentially with non-random bonds occurring in all flocks observed. Influences of social bonds on courtship display were also examined, and temporal changes in association were considered across time, season and year. Finally, to see any influence of animal health on bond preferences, scores of foot condition (used to identify and evaluate the presence and severity of pododermatitis on an individual bird) were analysed alongside of network measures for three flocks of flamingos. To measure enclosure usage, each species’ exhibit was measured and zones accessible to the birds were defined. As exhibit use can be based on resource use (and these resources can form differently-sized areas within an exhibit) a modified Spread of Participation Index (SPI) was used to provide an outcome between 1 (one area or resource used more than others) and 0 (equal use of all resource zones). Time-activity budgets were calculated for all flocks over daytime, and for one flock (measured using remote camera traps) over night. These data are presented in two chapters and demonstrate that captive flamingos can change their activity patterns in a similar manner to that noted in wild birds. Interestingly, flamingos are very active during the night and this provides useful data for zoo personnel to consider when re-assessing husbandry and management plans for these most ubiquitous of zoo birds.
63

Cooperation in a dynamic social environment

Dimitriadou, Sylvia January 2018 (has links)
Cooperative behaviour among unrelated individuals is an evolutionary paradox. Research suggests that an individual’s propensity to cooperate and its response to experiencing cooperation or defection from its social environment consistently varies among individuals and as a function of external factors. The biological and psychological underpinnings of such behavioural variation remain unknown; they can, however, provide more insight into the evolution and maintenance of cooperation among non-kin. This thesis explores the proximate effects of experiences of cooperation or defection from the social environment, as well as possible proximate drivers of cooperative behaviour, using the Trinidadian guppy (Poecilia reticulata) as a study system. Firstly, the behavioural rules underpinning an individual’s decision to cooperate or not with unfamiliar individuals in the presence of specific or non-specific information were explored. When fish had information about their social partner’s cooperativeness, they behaved in a manner consistent with direct reciprocity, copying their partner’s last move. When paired with an ostensibly novel partner, a different, or at least additional, behavioural rule seemed to be employed. In order to help understand the drivers of individual variation in cooperative behaviour, phenotypic selection on cooperativeness was carried out over three filial generations, resulting in fish of high cooperativeness (HC) and low cooperativeness (LC). The divergence of individual cooperativeness observed between the two phenotypic selection lines suggests that cooperative behaviour in the context of predator inspection is at least in part heritable. Cooperative behaviour of F3 fish was found not to correlate with boldness or exploratory behaviour; HC and LC fish did, however, differ in some aspects of sociability and agonistic behaviour. Possible proximate neuromodulatory mechanisms underlying these differences in cooperativeness were also explored, focusing on brain expression patterns for the isotocin receptor (itr) gene in F3 females. HC females were found to have higher mid-section itr expression levels than LC females. Finally, I explored the effects of experiencing cooperation or defection on monoaminergic neurotransmission, which is thought to instantiate the effects of such experiences on the individual’s internal state. My findings suggest that experiencing cooperation or defection from the social environment affects internal state; this phenomenon may be crucial for the appropriate adjustment of the behavioural response to such experiences, and for the emergence of behavioural rules such as generalised reciprocity. Taken together these results suggest that neuromodulatory mechanisms are pivotal for the perception of stimuli from the social environment in the tested cooperative context and that variation in cooperative behaviour may be underpinned by individual differences in the structural properties of such systems. They also provide insight into how behavioural input may affect the behavioural response to such experiences, and ultimately how such mechanisms may lead to the evolution and maintenance of cooperation.
64

The movement ecology of a breeding seabird : an investigation using accelerometry

Collins, Philip January 2018 (has links)
Animal movement is a ubiquitous process and can have consequences ranging from an individual’s energy expenditure to ecosystem dynamics. This study uses biologgers, primarily accelerometers, to record and examine the at-sea behaviours of black-legged kittiwakes (Rissa tridactyla) during their breeding period. Accelerometers record the acceleration of an instrumented animal to give an indication of their behaviour and movements, yet their output can be particularly difficult to interpret. As such, this thesis begins with a method developed for the assignation of coarse-scale behaviours to accelerometry data. The method is a simple yet objective approach intended to be widely applicable. Using this method, we construct time-activity budgets for incubating and chick-rearing kittiwakes and apply activity-specific estimates of energy expenditure to these behaviours. We identify how kittiwakes allocate their time and what the energetic consequences of variation in time-allocation are. We present empirical evidence for chick-rearing kittiwakes expending more energy than incubating birds and identify that kittiwakes exhibit behavioural compensation whereby they limit energy expenditure across both foraging trips and days. We also examine the flight behaviour of kittiwakes in relation to extrinsic conditions. We find that wind conditions do not seem to influence broader scale patterns in movements during foraging trips, however kittiwakes do display behavioural plasticity in response to wind conditions by optimising their flight speeds towards maximum range speeds. We also identify that to optimise flight speeds, kittiwakes change the strength at which they flap their wings, rather than the frequency. Finally we present a serendipitous observation of predation of kittiwake chicks by a peregrine falcon. Although not directly related to movement ecology, this study documents novel predatory behaviour and highlights the importance of biological forces other than movement. Overall, the work presented in this thesis demonstrates that by examining the movement of individuals, it is possible to gain insights into various important aspects of their biology.
65

Nest site selection by common eiders : relationships with habitat features, microclimate and incubation success

Fast, Peter 28 November 2006
Habitat selection theory presumes that organisms are not distributed randomly in their environments because of habitat-specific differences in reproductive success and survival; unfortunately, many previous studies were either unable or failed to look for evidence of processes shaping nest site selection patterns. Furthermore, little is known about adaptive nest site selection in northern environments where habitats often have little vegetation and time and climatic constraints may be pronounced. Therefore, I investigated patterns of nest site selection by common eider ducks (<i>Somateria mollissima</i>) at an island colony in Canadas Eastern Arctic, and looked for evidence of selective processes underlying these patterns by employing experimental and observational techniques.<p>I characterized physical features of (a) non-nest sites (b) active nest sites and (c) unoccupied nest sites that had been used in previous years. Habitat features that distinguished non-nest sites from unoccupied nest sites were also important in distinguishing between active and unoccupied nest sites during the breeding season. Active nest sites were closer to herring gull (<i>Larus argentatus</i>) nests, farther from the ocean and had organic substrates. In general, habitat features associated with nest use were not strongly associated with success after the onset of incubation. Nests near fresh water ponds were more successful in one study year, but in the other two study years successful nests were initiated earlier and more synchronously than were unsuccessful nests. Common eiders settled to nest first near the geographic centre of the colony, whereas sites near the largest fresh water pond were occupied later; distance to ocean had no observable effect on timing of nesting. Nest density was greater farther from the ocean, but timing of nest establishment did not differ between high and low density plots. <p>I tested whether moss or duck down placed in nest bowls could increase nest establishment, or advance laying date. I placed this extraneous material in bowls before nesting and found no difference in likelihood of nest establishment; however, bowls containing duck down were initiated earlier (or had higher survival) than those containing no nesting material. To investigate the role of nest shelter and microclimate in nest site choices and female body condition, I placed plywood nest shelters over established nests. Temperature probes indicated that artificially-sheltered females experienced more moderate thermal environments and maintained higher body weight during late incubation than did unsheltered females. However, few eiders nested at naturally-sheltered sites, possibly because nest concealment increases susceptibility to mammalian predators. My results suggest that eider nest choices likely reflect trade-offs among selective pressures that involve the local predator community, egg concealment, nest microclimate and energy use.
66

Nest site selection by common eiders : relationships with habitat features, microclimate and incubation success

Fast, Peter 28 November 2006 (has links)
Habitat selection theory presumes that organisms are not distributed randomly in their environments because of habitat-specific differences in reproductive success and survival; unfortunately, many previous studies were either unable or failed to look for evidence of processes shaping nest site selection patterns. Furthermore, little is known about adaptive nest site selection in northern environments where habitats often have little vegetation and time and climatic constraints may be pronounced. Therefore, I investigated patterns of nest site selection by common eider ducks (<i>Somateria mollissima</i>) at an island colony in Canadas Eastern Arctic, and looked for evidence of selective processes underlying these patterns by employing experimental and observational techniques.<p>I characterized physical features of (a) non-nest sites (b) active nest sites and (c) unoccupied nest sites that had been used in previous years. Habitat features that distinguished non-nest sites from unoccupied nest sites were also important in distinguishing between active and unoccupied nest sites during the breeding season. Active nest sites were closer to herring gull (<i>Larus argentatus</i>) nests, farther from the ocean and had organic substrates. In general, habitat features associated with nest use were not strongly associated with success after the onset of incubation. Nests near fresh water ponds were more successful in one study year, but in the other two study years successful nests were initiated earlier and more synchronously than were unsuccessful nests. Common eiders settled to nest first near the geographic centre of the colony, whereas sites near the largest fresh water pond were occupied later; distance to ocean had no observable effect on timing of nesting. Nest density was greater farther from the ocean, but timing of nest establishment did not differ between high and low density plots. <p>I tested whether moss or duck down placed in nest bowls could increase nest establishment, or advance laying date. I placed this extraneous material in bowls before nesting and found no difference in likelihood of nest establishment; however, bowls containing duck down were initiated earlier (or had higher survival) than those containing no nesting material. To investigate the role of nest shelter and microclimate in nest site choices and female body condition, I placed plywood nest shelters over established nests. Temperature probes indicated that artificially-sheltered females experienced more moderate thermal environments and maintained higher body weight during late incubation than did unsheltered females. However, few eiders nested at naturally-sheltered sites, possibly because nest concealment increases susceptibility to mammalian predators. My results suggest that eider nest choices likely reflect trade-offs among selective pressures that involve the local predator community, egg concealment, nest microclimate and energy use.
67

The effect of zoo visitors on the behaviour and welfare of zoo mammals

Farrand, Alexandra January 2007 (has links)
There is evidence that the presence of the visiting public affects the behaviour of zoo-housed mammals. Understanding the effect of visitors is important in improving animal welfare, achieving zoo conservation goals, increasing visitor education/entertainment, and facilitating interpretation of data on zoo animal biology. A series of studies and experiments focusing on the effect of zoo visitors on captive mammal behaviour is presented. The influence of visitor density on a range of primates and large carnivores is examined. Methodological concerns regarding the operational definition of visitor density in the literature are expressed and a clarification of terms which may be helpful when comparing previous research is provided. Visitor noise data, using an objective measure of the variable, and its relationship to visitor density are also presented. External and internal visual barriers between visitors and zoo animals were hypothesised to moderate the visitor effect and enrich the environment of the study groups. Camouflage nets mounted on the outside of enclosure viewing windows had little impact on primate or felid behaviour, with the exception of the Sumatran orangutan group, who showed a trend toward decreased social play in the presence of the external barrier. Polar bear behaviour showed evidence of an enriched environment, with trends toward increased levels of swimming and decreased levels of resting. An internal visual barrier, which prevented visitors from having visual contact with the golden lion tamarins when the nonhuman primates were behind it, was also tested and elicited more extensive trends toward behavioural change than did the nets. Both Sumatran orangutans and zoo visitors were provided with a similar puzzle feeder in an effort to enrich the orangutan enclosure, and improve the visitor experience. It was hypothesised that the orangutans might be stimulated by watching visitors manipulate the device, but this did not occur. Orangutan use of the puzzle feeder within their enclosure was also unaffected. Olfactory stimuli were introduced into primate and felid enclosures and visitor viewing areas to investigate the role olfaction may play in the visitor effect. Although olfactory stimuli had an extensive significant effect on the behaviour of the study groups when it was introduced into the enclosure, there was little change when visitors were associated with the olfactory stimuli which suggest there may not be an olfactory visitor effect in primates or felids. The effect of visitors on petting zoo-housed mixed-breed goats, llama, and Vietnamese pot-bellied pigs was studied and compared to their behaviour without the presence of visitors. The goats were unaffected and the llama showed only a trend toward decreased levels of sitting in the presence of visitors. The Vietnamese pot-bellied pigs were significantly affected by the presence of visitors, exhibiting decreased inactivity and social behaviour. The hypothesis that a sustained absence of visitors would result in a more intense visitor effect was tested and was not supported by the data. An additional experiment investigating the effect of visitor grooming on the petting zoo study species showed that, while visitors spent more time interacting with the animals in the grooming condition, xiv the behaviour of the study animals indicated that they did not find visitor grooming rewarding. Data on the interaction between visitor density and the various experimental techniques tested here indicate that visitor density may impact animal response to environmental enrichment, supporting previous findings in the literature. In the presence of visual barriers, foraging devices, and olfactory stimuli, the relationship between animal behaviour and visitor density changed significantly, both qualitatively and quantitatively. These results suggest that collecting visitor density data when testing environmental enrichment techniques could be helpful when assessing their effectiveness, ultimately improving the welfare of zoo-housed mammals. Based on the data presented here, in conjunction with the literature, a closing discussion outlines proposed refinements to the visitor effect research guidelines published by the British and Irish Association of Zoos and Aquariums (2005).
68

Factors affecting the timing and success of sockeye salmon spawning migrations

Crossin, Glenn Terrence 11 1900 (has links)
Migration timing is a conserved life-history trait. To address the hypothesis that reproductive hormones are principal determinants of migration timing, I physiologically biopsied over 1000 sockeye salmon and monitored their subsequent behaviour with acoustic and radio telemetry as they migrated from the Pacific Ocean toward and into the Fraser River, and then onward to distant spawning areas. Links between physiology, behaviour, and survival were examined. Circulating testosterone was found to be positively correlated with the rates of river entry in Late-run females but not in males, despite having concentrations that were equal if not higher than those of females. The notion of protandrous migration, in which males synchronize their activities to the reproductive and migratory schedules of females, was postulated as the basis for this difference. Once in river however, successful males and females were those that (1) took longest to enter the river, and (2) had high somatic energy, low testosterone, and low gill Na+,K+-ATPase activities. An experimental test of the effect of reproductive hormones on the regulation of migration timing proved inconclusive. Relative to controls, GnRH and (or) testosterone treatment did not influence rates of ocean travel by males. Unfortunately, no females were examined. Nevertheless, significant, positive correlations between initial testosterone and travel times were found irrespective of hormonal treatment, which was unexpected but consistent with the previous studies. In an experimental simulation of an ‘early’ migration, normally timed Late-run sockeye exposed to typical 10 ºC river temperatures and then released to complete migration were 68% successful. In contrast, salmon held at 18 °C and released were half as successful. The expression of a kidney parasite was near maximal in the 18 °C fish and undetectable in the 10 °C fish. Only gill Na+,K+-ATPase activity differed between groups, with a drop in the 18 °C fish. Though no clear stress, reproductive, or energetic differences were observed between groups, the ultimate effect of high temperature treatment was high disease expression, slowed migration speeds, and high migration mortality. Changes in reproductive schedules, due to changes in latitudinal ocean distributions, are discussed as potential causes of early migration by Late-run sockeye.
69

Snake harassment in the Cape ground squirrel (Xerus inauris): variation in anti-predator behaviours, predator discrimination and venom resistance in a facultative cooperative breeder.

Phillips, Molly A. 06 1900 (has links)
Predator harassment is an anti-predator behaviour that may increase a harasser’s risk of predation but decrease the potential for predation for other members of a group. The Cape ground squirrel (Xerus inauris) is a facultative cooperative breeder from southern Africa that harasses venomous snakes. The objective of my study was to examine predator harassment to determine: 1) whether predator harassment was part of alloparental care by comparing harassment behaviour among age and sex classes; 2) how individuals adjusted their behaviour against different snake species; 3) whether olfaction was used in discrimination of snakes; and 4) if individuals possessed venom resistance against venomous snakes. I found that females with juvenile offspring harass snakes longer and more intensely than other individuals, suggesting that predator harassment was a maternal behaviour. Squirrels increased harassment, inspection and vigilant behaviours with risk when exposed to both live snakes and snake odours suggesting they can use olfaction to discriminate snake predators. I also found no venom resistance in Cape ground squirrels concluding the cost of envenomation was significant.
70

Snake harassment in the Cape ground squirrel (Xerus inauris): variation in anti-predator behaviours, predator discrimination and venom resistance in a facultative cooperative breeder.

Phillips, Molly A. 06 1900 (has links)
Predator harassment is an anti-predator behaviour that may increase a harasser’s risk of predation but decrease the potential for predation for other members of a group. The Cape ground squirrel (Xerus inauris) is a facultative cooperative breeder from southern Africa that harasses venomous snakes. The objective of my study was to examine predator harassment to determine: 1) whether predator harassment was part of alloparental care by comparing harassment behaviour among age and sex classes; 2) how individuals adjusted their behaviour against different snake species; 3) whether olfaction was used in discrimination of snakes; and 4) if individuals possessed venom resistance against venomous snakes. I found that females with juvenile offspring harass snakes longer and more intensely than other individuals, suggesting that predator harassment was a maternal behaviour. Squirrels increased harassment, inspection and vigilant behaviours with risk when exposed to both live snakes and snake odours suggesting they can use olfaction to discriminate snake predators. I also found no venom resistance in Cape ground squirrels concluding the cost of envenomation was significant.

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