3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item Should I be eating that? eating, drinking and environmental ethics.(2011-11-08) Van Lierop, Mathew CarlWhat each individual eats and drinks can, and does, have a varying degree of impact on the environment in which they live. This impact can be on a local, regional or global scale and can range from affecting the viability of species’ populations, to contributing to global warming. This thesis sets out to explore what moral implications might exist with regard to the choices that individuals make within the context of environmental ethics. This paper discusses environmental considerations (as opposed to animal welfare or social implications for instance) and utilises various examples to illustrate different types of impacts and what this might mean. Conclusions indicating that moral obligations do exist are presented and argued for, but it is clear that there is certainly a complex matrix of factors that would (and should) affect the choices that each individual makes with regards to the food that they consume.Item Stereotypical behaviours in the striped mouse Rhabdomys pumilio: evaluating the coping hypothesis(2006-11-15T11:28:03Z) Van Lierop, Mathew CarlStereotypic behaviours are repetitive invariant behaviours that serve no obvious purpose and are common in both domestic and non-domestic captive animals. Stereotypies are regarded as indicators of poor welfare although the growing body of work pertaining to these behaviours has challenged many previously held notions of stereotypy. The most widely accepted, although frequently contested, hypothesis used to explain stereotypies is the coping hypothesis, which states that animals perform stereotypies to cope with the stress of adverse environments. The aim of my study was to investigate the fitness effects of stereotypy, and whether or not environmental enrichment protocols were effective in reducing or eliminating stereotypy in the adult striped mouse Rhabdomys pumilio. Both of these experiments were designed to evaluate the coping hypothesis. I intentionally used wild caught and F1 individuals to eliminate any potential captive selection bias that may exist in extant captive populations that could affect interpretation of fitness. For the first aim, 40 breeding pairs were assigned to one of four treatments: 1) stereotypic female and stereotypic male (S-S); 2) stereotypic female and non-stereotypic male (S-NS); 3) non-stereotypic female and stereotypic male (NS-S); and 4) non-stereotypic female and non-stereotypic male (NS-NS). Compared to non-stereotypic females, stereotypic striped mice females had better reproductive output, including larger litter size, higher growth rate, higher litter survival, shorter interlitter interval and shorter time to first litter. Reproductive success was higher in S-S and S-NS pairs, indicating that genetic and maternal effects jointly determined fitness in striped mice. Unlike other published research, maternal mass was not a predictor of fitness. For the second aim, I housed 20 non-stereotypic and 20 stereotypic striped mice (equal sex ratio) in barren cages for 60 days, and transferred them to enriched cages, and repeated this experiment with striped mice housed initially in enriched cages and transferred to barren cages. While there was a measurable reduction in stereotypy in individuals transferred from barren to enriched environment cages, no increase in stereotypy was noted in striped mice transferred from enriched to barren cages. These findings appear to concur with the coping hypothesis, that stereotypies become perseverative (e.g. bad habits) and difficult to disrupt. Non-stereotypic striped mice were not influenced by the swap. I conclude that the expression of stereotypy is a potential sign of positive welfare and that it may be worthwhile to specifically elicit stereotypic behaviours in order to improve the welfare, and in certain cases, breeding success, of captive animals. Moreover, I maintain that where necessary, effort should be applied to combating stereotypies before they arise, rather than attempting to eliminate them once they have actually developed.