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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.
1

The effects of an activity ball and ropes on pigs’ behaviours

Nilsson, Emma January 2012 (has links)
Rooting and exploring are two behaviours pigs in the wild spend considerable time doing. When kept in pens with limited access to bedding materials stress can originate and often lead to undesired behaviours. The purpose of this study was to investigate whether environmental enrichment in terms of ropes and an activity ball containing piglet food, can provide an outlet for their natural behaviours and thus reduce undesired behaviours. In total, 141 pigs were used and divided into three groups, control-, activity ball- and rope groups. The observation methods used were 1/0 recording and instantaneous recording with 15 second intervals. In the rope group a significant difference was seen in the interaction with enrichment, as it was higher on day 1. Between the three groups, a decrease in ear-, tail- and equipment biting was seen in the two enriched groups on day 1. On day 3 these difference could only be seen between the control group and the other two groups in equipment biting. However, few data ware collected and so we cannot confirm our hypotheses, concerning whether the environmental enrichments decreased the undesirable behaviours or not. However, most of our findings are in compliance with earlier studies as we among other things found that the rope worked better than the activity ball and that the interest of the enrichments decreased with time.
2

The impact of environmental enrichment on neurogenesis in an animal model of Autism

Reynard, Janine 10 September 2011 (has links)
Autism, a neurodevelopmental disorder, is assumed to result from early neural tube damage. Individuals with Autism exhibit macroencephaly during childhood. To examine increased neurogenesis as a factor in macroencephaly, the valproic acid (VPA) model of Autism was used to examine how exposure to enrichment affects neurogenesis in the dentate gyrus. To induce the model, pregnant rats received two 100mg/kg VPA injections on days 11, 12, and 13 of gestation. Half the pups in each group were exposed to enrichment from post-natal days 30-60. Neurogenesis was examined by fluorescence microscopy for the proliferation marker bromodeoxyuridine (BrdU) and neuronal specific nuclear marker (NeuN). Counts of double-labeled cells were done from the dentate gyrus, an area known for adult neurogenesis. Results indicate that neurogenesis is not abnormal in the VPA model and enrichment increases the neurogenesis similarly in both VPA and control animals. This research provides a better understanding of brain plasticity in the VPA model of Autism.
3

The impact of environmental enrichment on neurogenesis in an animal model of Autism

Reynard, Janine 10 September 2011 (has links)
Autism, a neurodevelopmental disorder, is assumed to result from early neural tube damage. Individuals with Autism exhibit macroencephaly during childhood. To examine increased neurogenesis as a factor in macroencephaly, the valproic acid (VPA) model of Autism was used to examine how exposure to enrichment affects neurogenesis in the dentate gyrus. To induce the model, pregnant rats received two 100mg/kg VPA injections on days 11, 12, and 13 of gestation. Half the pups in each group were exposed to enrichment from post-natal days 30-60. Neurogenesis was examined by fluorescence microscopy for the proliferation marker bromodeoxyuridine (BrdU) and neuronal specific nuclear marker (NeuN). Counts of double-labeled cells were done from the dentate gyrus, an area known for adult neurogenesis. Results indicate that neurogenesis is not abnormal in the VPA model and enrichment increases the neurogenesis similarly in both VPA and control animals. This research provides a better understanding of brain plasticity in the VPA model of Autism.
4

Stereotypy, personality and environmental enrichment

Joshi, Sneha January 2016 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy. Johannesburg, October 2015. / Animals in captivity are often raised in suboptimal environments, which lead to abnormal behaviours, such as stereotypic behaviour. Environmental enrichment can reduce or eliminate these behaviours to some extent. However, enrichments are not always successful in their intended purpose, which may be attributed to differences among individuals (i.e. personality). The overarching aim of my study was to investigate how environmental enrichment affected the expression of stereotypic behaviour in my study model, the African striped mouse, Rhabdomys dilectus, and to ascertain whether personality modulated the responses to enrichment. I conducted four experiments to test these aims. Firstly, I tested whether personality was associated with the development and expression of stereotypic behaviours. Results indicated that stereotypic striped mice were bold and showed a proactive coping style, while non-stereotypic striped mice were less bold and showed a reactive coping style. Furthermore, having a proactive coping style did not predict the onset of stereotypic behaviours. Nevertheless, individual differences in personality were observed even within stereotypic and non-stereotypic striped mice so that each group was not homogeneous for personality. Secondly, I tested whether personality was associated with the responses of stereotypic striped mice to enrichment. While stereotypic behaviours were reduced in enriched cages, individuals were not consistent in their behaviour, indicating flexible behavioural responses to the different cage complexities. Interestingly, these responses occurred irrespective of personality differences. There were no treatment-related differences in the behavioural responses of non-stereotypic striped mice. Thirdly, I examined whether the age at which striped mice were introduced to the environmental enrichment influenced their behavioural responses. Age did not affect the behavioural responses of stereotypic or non-stereotypic mice to the cages of different complexity. Surprisingly, while stereotypic behaviours were reduced in the enriched treatments, not all stereotypic mice responded to enrichment in the same manner, implying flexible behavioural responses. Moreover, these behavioural responses also occurred regardless of the individual’s personality type. There were no age-related differences in the behavioural responses of non-stereotypic striped mice. Finally, I investigated the purpose of wheel running, either as an enrichment or as a re-directed stereotypic behaviour, in stereotypic striped mice, because there is much debate about its use as an enrichment. Due to individual differences in responses to the running wheel, wheel running appeared to be both an enrichment and a re-directed behaviour. In conclusion, my study provides the first empirical data for the theory that stereotypic animals have different personalities to non-stereotypic animals. Nonetheless, this dichotomy between stereotypic and non-stereotypic striped mice at the group level masked individual responses within groups, with individuals flexibly altering their behaviour, depending on the environment to which they were exposed, which in turn affected the efficacy of environmental enrichment. My study suggests that the welfare and well-being of animals requires an assessment of individual trajectories in the development of stereotypic behaviours.
5

The Effects of Housing Conditions on Anxiety-Like Behavior

Jiang, Jade January 2011 (has links)
No description available.
6

Effects of mecamylamine on nicotine-induced conditioned hyperactivity and sensitization in differentially reared rats

Ha, Rosemary January 1900 (has links)
Master of Science / Department of Psychology / Mary E. Cain / Rats reared in an enriched condition (EC) with novel stimuli and social contact with cohorts display less sensitization to nicotine than rats reared under impoverished conditions (IC). However, it is currently unknown what effect differential rearing has on nicotine-induced conditioned hyperactivity. The present study determined whether differential rearing affects conditioning to a nicotine-associated context. In addition, this study also examined the effects of mecamylamine, an antagonist to nicotinic acetylcholine receptors, on conditioned hyperactivity and sensitization. This antagonistic drug has been shown to attenuate the locomotor effects of nicotine. In the current study, EC, IC, and social condition (SC) rats were reared from 21 to 51 days of age before training for the acquisition of conditioned hyperactivity and sensitization. Nicotine (0.4 mg/kg) was administered prior to 1-h locomotor sessions. Conditioned hyperactivity testing followed. Rats then received 5 sessions of sensitization training followed by a 16-day drug-free rest period before being tested for sensitization. Mecamylamine (1.0 mg/kg) was administered to rats prior to the conditioned hyperactivity test and sensitization test. Nicotine treatment resulted in sensitization and conditioned hyperactivity in all differential rearing groups. EC rats displayed less locomotor activity in response to nicotine than both IC and SC rats. Pretreatment with mecamylamine blocked the expression of conditioned hyperactivity in EC and SC rats and attenuated sensitization in all three rearing groups. These findings suggest that environmental enrichment may alter nAChR binding during development and may be a protective factor in the initiation and relapse of smoking behavior.
7

Miljöberikning för domesticerade lamadjur i en djurpark : En studie om lama (Lama glama) och alpacka (Vicugna pacos) och deras beteenden

Pörhölä, Sofia January 2014 (has links)
The purpose of this study was to enrich the environment for llama (Lama glama) and alpaca (Vicugna pacos) in a zoo. The zoo is located in northern Sweden (Umeå, Mickelträsk). The llama herd consists of three individuals of breed qara, two males and one female and the alpaca herd consists of six individuals of breed huacaya, one male, four females and one foal. The species lived in separate enclosures, they lived outside all year round and they had a shelter for wind and rain protection. They feed on pasture and were fed hay and pellet concentrate. A behavioral-study was carried out in April 2014, a five-day study where each of the species were observed 3 h a day, 1,5 h in morning and afternoon. The behavioral of llama and alpaca were observed individually and each behavior was observed in terms of duration and frequency. The study observed if the animals had a possibility to implement their natural behaviors in their enclosures and whether they showed any abnormal- or stereotypical behaviors that can occur in captivity. The questions I wanted to answer were: (1) what behaviors are occurring, (2) Is it possible to indicate from the behaviors if the animals are doing well or not, (3) Is there a difference in behaviors in the morning and afternoon? (4) Is there a difference between the sexes? (5) What actions should be undertaken to enrich and improve the habitat for llamas and alpacas in a zoo? The results from the study show that llamas and alpacas show many normal and natural behaviors, no abnormal-or stereotypical behaviors were visible. Some behaviors were more common in morning and some in afternoon and there were differences in behaviors between the sexes. Example for some environmental enrichment for the llamas and alpacas in the zoo was to add logs, trees, shrubs and sand piles to the enclosure.
8

Potential environmental enrichment for zebrafish used in regulatory toxicology

Wilkes, Luanne January 2011 (has links)
The aim of environmental enrichment is to alter the environment of a captive animal in a way that results in improved mental and physical welfare. The technique has been utilised effectively for many years for captive mammals in a variety of settings. However, until now it has never been considered as a way of improving the welfare of aquatic animals such as fish. Fish that are used in regulatory toxicology studies are at present maintained solely in barren tank environments. Little is known about how these types of environments affect the well-being of the animals residing there and whether they impact either physiological heath or behavioural repertoire. This thesis aims to address this gap in the knowledge regarding the potential for environmental enrichment to improve the welfare of fish used in regulatory toxicology. More specifically it looks at two types of enrichment and the effects of these on the commonly used model species, the zebrafish (Danio rerio). The first type of enrichment studied was glass rod structures of varying heights provided to increase tank complexity and provide refuge. The glass structures did not produce any quantifiable benefits in unstressed fish and appeared to delay the formation of stable social hierarchies. When fish were stressed by a period of chasing, the presence of the glass rods appeared to reduce the magnitude of the cortisol response. Whilst this could be viewed as a potential benefit, it was felt that it would not outweigh the costs of this type of enrichment. The second type of enrichment studied was provision of airstones. Again, no clear evidence was found that fish in tanks with airstones experienced an improvement in welfare. The main observation was the vast increase in mortality in tanks containing these airstones, in particular, those of a smaller size. Regardless of the physiological cause underlying this result, this can only be viewed as a negative consequence and one that appears to rule out airstones as an effective form of enrichment for this species and strain of fish. It was also observed that both stress and the presence of enrichment influenced the absolute deviation from the mean in several endpoints. Since changes in endpoint variation will have effects both on the number of animals required to statistically measure environmentally relevant effects this is a factor that should be considered when researching methods of environmental enrichment. Finally, results from these studies suggest the possibility that laboratory zebrafish do not require the addition of environmental enrichment to tanks in order to promote maximum welfare. Furthermore, as considerable costs would be involved in implementing many types of enrichment (relating to manufacture, cleaning, incompatibility of results with previous studies etc.) it is likely that observed benefits would have to be both substantial and well established in order for changes in regulatory guidelines to take place. For a species such as zebrafish that are extremely easy to breed and maintain in the laboratory with minimal amounts of disease, social problems or mortalities, it may be that current conditions are satisfactory.
9

The effects of environmental enrichment on nicotine sensitization in a rodent model of schizophrenia

Schlitt, Marjorie A, Cummins, Elizabeth D, Peterson, Daniel J, Brown, Russell W 01 May 2014 (has links)
Environmental enrichment, for more than fifty years, has shown to increase learning in behaviors and to alter some brain structures (Renner and Rosenzweig). Some brain changes that occur when environmental enrichment is implemented include the following: increases in cortical thickness, especially the occipital cortex, increases in size of neuronal cell bodies, number of dendrites and dendritic spines, increases in astrocyte branching, increases in the number of brain blood capillaries, and increases in mitochondria (an indication of higher metabolic activity) (Stairs and Bard). It has been shown in research studies that rats in the environmental enrichment group are less sensitive to nicotine effects, both repeated and acute, than rats in isolated situations (Green et al). This is so because enrichment changes the intensity of the acute administration of drugs of abuse. Rats are stimulated by the environment, rather than a particular stimulant.
10

Innovative environmental enrichment method for Pallas cat (<em>Felis manul)</em>

Rioldi, Emmanuela January 2010 (has links)
<p>Due to the expansion of the human population we are an increasing threat to all wild animals. They are driven to exist in smaller areas and in the worst case scenario extinction. Zoos are being encouraged to improve the animal’s physical and social surroundings. Environmental enrichment is a term used for such improvements. In this behavioural study, the enrichment introduced to two Pallas cats (<em>Felis manul</em>) at Parken Zoo in Eskilstuna, Sweden, consisted of a fishing rod and a clothes peg with a dead mouse or chick attached. The intention was to see if the feeding enrichment could increase activity levels and how the cats were using their enclosure. The enclosure was divided into seven zones which have a varying degree of opportunities for the animals to climb, hide and rest above ground level. The environmental enrichment effects on the Pallas cats´ behaviour, activity levels and use of the enclosure were measured and recorded using instantaneous scan sampling, and the mean value was calculated for each individual. The behavioural and enclosure results proved that enrichment benefits the cats activity levels. The behaviours that showed a variation when presented with enrichment were: walking, climbing, grooming, aggressive behaviour, out of sight behaviour, crouching position, sitting and standing still.  The results showed that the cats preferred the zones in the enclosure that offered a larger view of the nearby enclosures. This study shows that providing captive felids with inexpensive, easy to administer enrichment objects can have profound effects on activity behaviours and their enclosure.</p><p> </p>

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