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Master of Science / Department of Horticulture and Natural Resources / Ryan L. Sharp / Elk in Kansas were an abundant tallgrass prairie species prior to European settlement. Elk were extirpated in the 1870s and reintroduced in the late 1980s. After three decades, wild populations continue to be low in spite of good biological conditions. Broad, low stakeholder acceptance are a suspected limiting factor. Wildlife stakeholder acceptance capacity (WSAC) and tolerance models helped to frame results from an internet based survey (n=460) directed to all Kansas counties. Respondents reported high mean positive wildlife values, acceptance for elk population increase, and significantly (p<0.05) higher personal acceptance for elk than the level of acceptance they perceived in others. Encountering wild elk in Kansas was unrelated to acceptance but strongly predicted providing wildlife habitat on private land. Hunters reported the strongest wildlife attitudes but this result was not correlated with elk acceptance. Intangible benefits (e.g. positive meaningful experiences) strongly affected (p<0.00) wildlife attitudes and elk acceptance. Tangible benefits (e.g. money) was unrelated to wildlife values but respondents who reported tangible benefits from four or more wildlife species showed higher acceptance for elk on personal property than groupings based on other variables. WSAC theory suggests social carrying capacity for elk is significantly above the current population and Kansans are more accepting of wildlife than previously thought. Wildlife managers may be encouraged by these results to conduct their own social feasibility study regarding increasing the elk population to a more ecologically sustainable level.

The finding that the performance of a response during periods of drug exposure facilitates the development of tolerance to the effects of the drug on that response is commonly referred to as contingent drug tolerance. Contingent tolerance is typically demonstrated in before-and-after design experiments. One group of subjects receives drug before the performance of the criterion response (drug-before-test condition) and a second group of subjects receives drug after the performance of the criterion response (the drug-after-test condition). The usual finding is that substantial tolerance develops in the drug-before-test condition, but no tolerance whatsoever develops in the drug-after-test condition. Such demonstrations of contingent tolerance have led to the drug-effect theory of tolerance: the theory that tolerance to a particular drug effect is an adaptive response to the experience of that particular drug effect. The purpose of this thesis was to clarify the relation between drug exposure, drug effects, and the development of tolerance. Several experiments have demonstrated that no tolerance whatsoever develops to anticonvulsant drug effects if convulsive stimulation is administered prior to each drug injection (drug-after-test condition), rather than afterwards (drug-before-test condition). Be that as it may, a different experimental design was used in Experiments 1 and 2 to show that small amounts of tolerance develop in the absence of concurrent convulsive stimulation. Rats that received either 3 intraperitoneal injections of diazepam (5.0 mg/kg) per day for 10 days (Experiment 1) or 1 gastric intubation of ethanol (5 g/kg) for 21 days (Experiment 2) were significantly more tolerant than vehicle controls; however, the tolerance could be detected only by a sensitive savings measure. The purpose of Experiment 3 was to test a novel interpretation for the inconsistency between Experiments 1 and 2 on the one hand and the repeated failure to observe tolerance to anticonvulsant drugs following drug exposure without concurrent convulsive stimulation in the drug-after-test condition of before-and-after experiments on the other. This hypothesis is that small amounts of tolerance do develop following each drug injection in the drug-after-test condition but that it is dissipated the next day by the convulsive activity experienced in the absence of the drug. To test this hypothesis, one group of amygdala-kindled rats received 15 diazepam injections (2.5 mg/kg) each before a convulsive stimulation, one group received 15 diazepam injections each after a convulsive stimulation, one group received 15 diazepam injections with no convulsive stimulation, and one group received 15 vehicle injections either with or without convulsive stimulations. The drug-before-stimulation rats developed substantial tolerance as has been frequently reported, and the hypothesis was confirmed by the finding that the drug-only rats developed tolerance significantly faster than the rats in the drug-afterstimulation group and the rats in the vehicle-control group. The results of these experiments make two important points. First, tolerance develops following drug exposure even when the criterion response is not performed during drug exposure —albeit substantially less than when it is performed. Presumably, this is because a few of the neural circuits that are active during a convulsion are spontaneously active following the drug administration. Second, the reason why the subjects in the drug-after condition display no evidence of tolerance is because the drug-free performance of the criterion response prior to each drug exposure causes any tolerance that has developed to dissipate. / Arts, Faculty of / Psychology, Department of / Graduate

C. halicacabum (Sapindaceae) is an invasive plant that is considered a nuisance species in Texas riparian environments. Little is known of the tolerance of C. halicacabum to flooding and drought; however, this information may provide insight into the characteristics that contribute to C. halicacabum purported invasiveness. C. halicacabum seedlings (n = 92) were exposed to one of four levels of water availability (flooded, saturated, intermediate and dry) over six weeks under greenhouse conditions. Plant performance was affected by water availability; however, there was no effect on survivorship. Flooded and saturated plants exhibited morphological adaptations; producing adventitious roots, hypertrophy, and aerenchyma tissue. Morphological measures, anatomical responses, and patterns of biomass allocation all indicate that C. halicacabum is able to survive periodic inundation, perform in saturation, and establish and thrive on the drier end of a moisture gradient.

The aim of this study was to determine withdrawal periods and tissue tolerance of intramammary antibiotics (Curaclox LC, Spectrazol Milking Cow and Rilexine 200 LC) in goats, measured in different ways, and to evaluate the effects of related factors. Method: Three experimental trials were conducted. Trial 1 and Trial 2 were conducted at the Faculty of Veterinary Science, Onderstepoort using the goat herd of the Onderstepoort Teaching Animal Unit (OTAU) (Herd A), while Trial 3 was conducted on a commercial goat dairy in the Limpopo Province of South Africa (Herd B). In addition, four goats with clinical mastitis from a smallholding close to the Faculty of Veterinary Science at Onderstepoort were studied (Herd C). This herd consisted of 13 lactating Saanen and Saanen/Toggenburg crossbred dairy goats. In all trials foremilk was stripped, teats were disinfected and a milk sample was taken from each udder half of each goat (half-milk samples). In all three trials the following milk samples were taken: two sets of half samples and a composite sample (before, during and after treatment). The California Milk Cell Test (CMCT) and conductivity measurements were performed. In Trial 3 the conductivity meter became non-functional on the second day, and thus the conductivity test was eliminated from then on. Each udder half was milked separately and milk volume was recorded. The temperature of goats was taken and recorded to identify sick animals. All goats in the treatment group were treated. In all three trials after treatment, sampling continued until SCC returned to baseline and until there were at least two consecutive negative TRIS tests for each goat, approximately 10 days. Milk production was based on the following milk production groups: low (less than 1.3L), medium (1.3L to 1.5L) and high (greater than 1.5L) daily milk production. The antibiotics used in these trials were selected for being commonly used, broad-spectrum preparations. Trial 1, a semi-synthetic penicillin based intramammary preparation (Curaclox LC, which contains 75mg sodium ampicillin and 200mg sodium cloxacillin per dose plus blue dye). Curaclox LC G2615, (Norbrook (Pharmacia AH) P.O. Box 10698 Centurion, 0046), cloxacillin 200mg, ampicillin 75mg, blue dye/ 4.5g syringe. Trial 2, a cefuroxime 250mg based intramammary product (Spectrazol Milking Cow, Schering-Plough). Spectrazol milking cow, cefuroxime, 250mg, S4 Intramammary Injection 83/594, (Schering-Plough Animal Health, P.O. BOX 46, Isando, 1600). Trial 3, a cephalexin 100mg, neomycin sulphate 100mg and prednisolone based intramammary product, Rilexine (SA) 200LC injection 83/638, (Logos Agvet (Virbac), Private bag X115, Halfway House, 1685). Curaclox LC G2615, Norbrook (Pharmacia AH), cloxacillin 200mg, ampicillin 75mg, blue dye/ 4.5g syringes. In the clinical mastitis cases (Herd C); Goat 1 was treated with Spectrazol milking cow (as above), Goat 2 was treated with Curaclox LC (as above), Goat 3 was treated with Curaclox LC in the left udder half and Goat 4 was treated with Curaclox LC in the right udder half (as above). Results: Trial 1: Curaclox LC The mean withdrawal periods for the product Curaclox LC (intramammary) as measured by Thermo Resistant Inhibitory Substances (TRIS), colour dye, Parallux testing for cloxacillin and ampicillin, on eight relatively low producing Saanen dairy goats (Trial 1) were 74h ± 19.21; 90h ± 16.97; 99h ± 9.07 and 93h ± 11.41 respectively. The withdrawal period for Curaclox LC recommended for use in cattle (72h) was significantly shorter than the withdrawal periods as measured by colour dye (P < 0.001), Parallux testing for cloxacillin (P < 0.001) and Parallux testing for ampicillin (P < 0.05) in Trial 1. There was a significant difference of withdrawal periods as measured by TRIS (P < 0.05) and colour dye (P < 0.05) between goats with and without clinical mastitis in Trial 1 Trial 3: Curaclox LC The mean withdrawal periods for Curaclox LC as measured by TRIS, colour dye, Parallux testing for cloxacillin and ampicillin, on 12 relatively high producing Saanen and Saanen-Toggenburg crossbreed dairy goats (Trial 3) were 42h ± 7.08; 65h ± 60.26; 77h ± 13.56 and 71h ± 12.65 respectively. The withdrawal period for Curaclox LC recommended for use in cattle (72h) was significantly longer than the withdrawal periods as measured by TRIS (P < 0.001) and colour dye (P < 0.001) in Trial 3. Curaclox LC: Trials 1&3 combined The mean withdrawal periods for Curaclox LC as measured by TRIS, colour dye, Parallux testing for cloxacillin and ampicillin, for Trials 1&3 combined were 59h ± 24.31; 76h ± 17.70; 87h ± 16.10 and 80h ± 16.23 respectively. The withdrawal period for Curaclox LC recommended for use in cattle (72h) was significantly longer than the withdrawal periods as measured by TRIS (P < 0.001) in Trials 1&3 combined. Trial 2: Spectrazol Milking Cow The mean withdrawal periods for Spectrazol Milking Cow (intramammary) as measured by TRIS on seven relatively low producing Saanen dairy goats (Trial 2) was 95h ± 17.23. The withdrawal period for Spectrazol Milking Cow recommended for use in cattle (60h) was significantly shorter than the withdrawal period as measured by TRIS (P < 0.001) in Trial 2. Trial 3: Rilexine 200 LC The mean withdrawal periods for Rilexine 200 LC (intramammary) as measured by TRIS on 20 relatively high producing Saanen and Saanen-Toggenburg crossbreed dairy goats (Trial 3) was 37h ± 9.94. The withdrawal period for Rilexine 200 LC recommended for use in cattle (96h) was significantly longer than the withdrawal period as measured by TRIS (P < 0.001) in Trial 3. The regression model for goats with clinical mastitis was: Withdrawal period as measured by TRIS = 30.21 + 4.692 (sampling time) + 22.11 (udder palpation) – 13.6 (floccules) – 0.00649 (volume) (R2 = 95.7%, standard error of regression = 3.41) There was great variation in Somatic Cell Count (SCC) between trials, ranging from 1928 X 103cells/mL to 9274 X 103cells/mL for infected udder halves and from 1817 X 103cells/mL to 3639 X 103cells/mL for non-infected udder halves, at the morning milking. At the evening milking SCC ranged from 1927 X 103cells/mL to 6415 X 103cells/mL for infected udder halves and from 2103 X 103cells/mL to 3304 X 103cells/mL for non-infected udder halves. SCC of udder halves with clinical mastitis ranged from 7053 X 103cells/mL to 7948 X 103cells/mL for udder halves in which bacteria could not be isolated and from 6476 X 103cells/mL to 8479 X 103cells/mL in udder halves from which bacteria was isolated. Most of the variation in SCC was unexplained. In this research all SCC values were determined using the Fossomatic 90 counter and the arithmetic means were reported. The factors valid for determining clinical mastitis were the presence of floccules in the milk and high SCC, with or without udder damage and/ or bacteria. Intramammary infection (IMI) was determined by the presence or absence of bacteria only. Conclusions and Recommendations: The variability in SCC was largely unexplained, and an increased SCC did not necessarily indicate an intramammary infection in goats, as it does in cows. Therefore further, research is required to assess SCC and all possible factors affecting it. Further research is also required to find a more reliable method for mastitis diagnosis apart from SCC, for example, NAGase. The “Goatside” tests used (California Milk Cell Tests, CMCT) and SCC on their own were not reliable methods of mastitis diagnosis and should be accompanied by microbiological tests. However, CMCT and SCC were indicators of tissue tolerance and udder irritation. Tissue irritation is considered to indicate the limit of tissue tolerance. In healthy goats Spectrazol Milking cow caused the least tissue irritation, followed by Rilexine 200 LC, and Curaclox LC. However, for goats with clinical mastitis Rilexine 200 LC caused the least tissue irritation followed by Curaclox LC; and Spectrazol Milking cow caused the most tissue irritation in goats with clinical mastitis. Withdrawal periods of healthy goats and goats with clinical mastitis also differed for each product. Further research is necessary to determine withdrawal periods and tissue irritation of different intramammary products on goats with clinical mastitis. Withdrawal period was affected by volume of milk produced, due to the dilution factor of continuous milk secretion. High producers had shorter withdrawal periods than low producers. However, treatment with intramammary antibiotics did not significantly affect the volume of milk produced. Further research is required to assess the effect of milk production volume on withdrawal periods when comparing withdrawal periods of different products. Antibiotic withdrawal periods on goat milk were different from those recommended for use in cattle for each of the products used and for the different intramammary antibiotics used. The withdrawal periods recommended for use cattle have a 24h safety margin added to the longest withdrawal period in the trial. In this research 24h safety margins were not added in the original tables. Therefore, in practice 24h safety margins should be added to all withdrawal periods in this research. Later the 24h safety margins were subtracted from the withdrawal periods recommended for use in cattle in order to obtain a rough estimate of the actual withdrawal periods in cattle. In this analysis all withdrawal periods measured by different methods for goats were significantly different from withdrawal periods recommended for use in cattle (-24h safety margin). However, in the original tables not all withdrawal periods for goats as measured by different methods were significantly different from those in cattle (with 24h safety margin). Conductivity was found to be an unreliable “Goatside” test. / Dissertation (MSc (Veterinary Science))--University of Pretoria, 2005. / Production Animal Studies / unrestricted

As rising sea temperatures and increases in the frequency, duration, and intensity of marine heatwaves threaten coral survival at a global scale, research on the capacity of corals to acclimatize and adapt to changing environments has become a high priority. Understanding how environmental parameters shape coral thermal performance across habitats is crucial to identify populations with high vulnerability or high thermal tolerance to future ocean warming. In recent studies, corals from high temperature variable environments (HVE) have shown increased thermal tolerance compared to corals from low temperature variable environments (LVE). Here, I investigate if these phenotypes are shaped by acclimatization, habitat-specific adaptation, or a combination of both, in the branching coral, Acropora hemprichii, by reciprocally transplanting individuals between a back (HVE) and front reef (LVE). After ten months of acclimatization, comparisons of photosynthetic efficiency (photosystem II), mortality, and bleaching recovery was assessed for > 2 months between coral ramets following a natural bleaching event in the central Red Sea. In tandem, coral bleaching severity and recovery in each reef environment was assessed to genus level by photographic surveys of fixed belt transects. Bleaching between reef sites was compared against bleaching in treatments to differentiate the role of habitat specific adaptation and acclimatization in the corals. This study aims to elucidate the evolutionary mechanisms driving coral habitat-specific thermal stress tolerances, which may inform coral reef management and restoration efforts.

Soil salinity is a major abiotic stress for land plants, and multiple mechanisms of salt tolerance have evolved. Tissue tolerance is one of these mechanisms, which involves the sequestration of sodium into the vacuole to retain low cytosolic sodium concentrations. This enables the plant to maintain cellular functions, and ultimately maintain growth and yield. However, the molecular components involved in tissue tolerance remain elusive. Several candidate genes for vacuolar sodium sequestration have recently been identified by proteome analysis of vacuolar membranes purified from the salt-tolerant cereal Hordeum vulgare (barley). In this study, I aimed to characterize these candidates in more detail. I successfully cloned coding sequences for the majority of candidate genes with primers designed based on the barley reference genome sequence. During the course of this study a newer genome sequence with improved annotations was published, to which I also compared my observations. To study the candidate genes, I used the heterologous expression system Saccharomyces cerevisiae (yeast). I used several salt sensitive yeast strains (deficient in intrinsic sodium transporters) to test whether the candidate genes would affect their salt tolerance by mediating the sequestration of sodium into the yeast vacuole. I observed a reduction in growth upon expression for several of the gene candidate under salt-stress conditions. However, confocal microscopy suggests that most gene products are subject to degradation, and did not localize to the vacuolar membrane (tonoplast). Therefore, growth effects cannot be linked to protein function without further evidence. Various potential causes are discussed, including inaccuracies in the genome resource used as reference for primer design and issues inherent to the model system. Finally, I make suggestions on how to proceed to further characterize the candidate genes and hopefully identify novel sodium transporters from barley.

Four Fibroporia radiculosa isolates undergoing decay of untreated and 1.2% ammoniacal copper citrate treated wood were evaluated for differential expression of citrate synthase (CS), isocitrate lyase (ICL), glyoxylate dehydrogenase (GLOXDH), succinate/fumarate antiporter (ANTI), and a copper resistance-associated ATPase pump (ATPase). Samples were analyzed at 2, 4, 6, and 8 weeks for oxalate and protein production, enzyme activities, and gene expression. ATPase pump expression was increased in the presence of copper when initial oxalate concentrations were low, suggesting it functions in helping the fungus adapt to the copper-rich environment by pumping toxic copper ions out of the cell. A connection in expression levels between CS, ANTI, ICL, and GLOXDH for the four isolates was found suggesting the production of oxalate originates in the mictochondrial TCA cycle (CS), shunts to the glyoxysomal glyoxylate cycle (ANTI), moves through a portion of the glyoxylate cycle (ICL), and ultimately is made in the cytoplasm (GLOXDH).

Trait mindfulness has been found to be a beneficial characteristic of athletes. However, the research on mindfulness interventions has been limited, poorly described, and poorly designed. The current study sought to determine whether a brief mindfulness intervention improves distress tolerance among athletes. In addition, this experiment tested the impact of cultivating mindfulness on psychological variables that may be important for sport such as anxiety, happiness and capacity for stress. Athletes were randomly assigned to one of the three intervention conditions (brief mindfulness, sham mindfulness and no-intervention control). All participants completed distress tolerance measures, a motor performance measure under distressing conditions, and self-reported psychological measures. These measures were administered at pre- and post-intervention. Results indicated that the brief mindfulness intervention did not result in significant improvements in the primary outcome variables, in comparison to the sham mindfulness and no-intervention control groups. Strengths and limitations of the study, as well as future directions are provided.

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