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This study assessed the intentions with regard to fertility and use of contraception by women living with HIV/AIDS. The study was a quantitative cross-sectional study on a sample of 362 HIV-positive women in the ART follow-up unit in Adama Hospital Medical College. Large numbers of HIV-positive women with no income, housewives, illiterates and women in the age group of 28-32 years declared their intention to fall pregnant. The most prevalent family planning method among the HIV-positive women before their HIV diagnosis was injectables. After wards the most popular method of contraception was the condom. The results suggest that the counselling about condom use that is offered to HIV positive women yields results, as more women adopt this method of contraception. This is important in view of prevention of HIV infections and re-infections. / Health Studies / M. A. (Public Health)

The European honey bee (Apis mellifera) has been present in Australia for approximately 150 years. For the majority of that time it was assumed this species could only be of benefit to Australia‘s natural ecosystems. More recently however, researchers and conservationists have questioned this assumption. Honey bees are an introduced species and may be affecting native fauna and flora. In particular, native bees have been highlighted as an animal that may be experiencing competition from honey bees as they are of similar sizes and both species require nectar and pollen for their progeny. Most research to date has focused on indirect measures of competition between honey bees and native bees (resource overlap, visitation rates and resource harvesting). The first chapter of this thesis reviews previous research explaining that many experiments lack significant replication and indirect measures of competition cannot evaluate the impact of honey bees on native bee fecundity or survival. Chapters two and four present descriptions of nesting biology of the two native bee species studied (Hylaeus alcyoneus and an undescribed Megachile sp.). Data collected focused on native bee fecundity and included nesting season, progeny mass, number of progeny per nest, sex ratio and parasitoids. This information provided a picture of the nesting biology of these two species and assisted in determining the design of an appropriate experiment. Chapters three and five present the results of two experiments investigating the impact of honey bees on these two species of native bees in the Northern Beekeepers Nature Reserve in Western Australia. Both experiments focused on the fecundity of these native bee species in response to honey bees and also had more replication than any other previous experiment in Australia of similar design. The first experiment (Chapter three), over two seasons, investigated the impact of commercial honey bees on Hylaeus alcyoneus, a native solitary bee. The experiment was monitored every 3-4 weeks (measurement interval). However, beekeepers did not agist hives on sites simultaneously so measurement intervals were initially treated separately using ANOVA. Results showed no impact of honey bees at any measurement interval and in some cases, poor power. Data from both seasons was combined in a Wilcoxon‘s sign test and showed that honey bees had a negative impact on the number of nests completed by H. alcyoneus. The second experiment (Chapter 5) investigated the impact of feral honey bees on an undescribed Megachile species. Hive honey bees were used to simulate feral levels of honey bees in a BACI (Before/After, Control/Impact) design experiment. There was no impact detected on any fecundity variables. The sensitivity of the experiment was calculated and in three fecundity variables (male and female progeny mass and the number of progeny per nest) the experiment was sensitive enough to detect 15-30% difference between control and impact sites. The final chapter (Chapter six) makes a number of research and management recommendations in light of the research findings.

This study assessed the intentions with regard to fertility and use of contraception by women living with HIV/AIDS. The study was a quantitative cross-sectional study on a sample of 362 HIV-positive women in the ART follow-up unit in Adama Hospital Medical College. Large numbers of HIV-positive women with no income, housewives, illiterates and women in the age group of 28-32 years declared their intention to fall pregnant. The most prevalent family planning method among the HIV-positive women before their HIV diagnosis was injectables. After wards the most popular method of contraception was the condom. The results suggest that the counselling about condom use that is offered to HIV positive women yields results, as more women adopt this method of contraception. This is important in view of prevention of HIV infections and re-infections. / Health Studies / M. A. (Public Health)

Call number: LD2668 .T4 1958 O65

Call number: LD2668 .T4 1985 F47 / Master of Science

Call number: LD2668 .T4 1985 L825 / Master of Science

A series of experiments were conducted to investigate the regulatory mechanisms governing the absence of and the initiation of pulsatile pituitary LH secretion during the infantile and prepubertal periods of development in the bull calf. In the first experiment, patterns of hypothalamic GnRH secretion into hypophyseal portal vessels were measured in sixteen Holstein bull calves at 2, 5, 8 and 12 weeks of age. The results of this study correlated the attainment of an hourly rate of pulsatile GnRH release to the onset of prepubertal LH secretion. In the second experiment, nine Holstein bull calves were infused with exogenous GnRH (200 ng) on an hourly basis from 1 to 6 weeks of age. From this experiment, we were able to demonstrate that an hourly rate of pulsatile GnRH release stimulates the age-associated changes in the hypothalamic-pituitary axis necessary for initiating pituitary LH secretion during the transition from the infantile to prepubertal period of development.

Busseola fusca is an indigenous lepidopteran pest species in tropical Africa, attacking several grain crops. Crop loss caused by this pest can be as high as 100 % depending on conditions. Despite it being a major pest in Africa, occurring in contrasting climatic zones, only a few studies have been published on its developmental biology. The effect of temperature on the development of B. fusca was studied at five different temperature regimes namely 15, 18, 20, 26 and 30 ± 1 °C and 70 ± 30 % relative humidity (RH) with 14L: 10D photoperiod. The number of instars for B. fusca was also determined. The most favourable temperature as well as the upper threshold temperature for larval development was found to be between 26 and 30 °C. Total development period was 152.6 to 52.6 days, respectively, at 15 °C, and 26 - 30 °C. The thermal constants for B. fusca was 99.50, 536.48, 246.25 and 893.66 °D and lower temperature threshold was 10.36, 8.14, 8.99 and 8.84 °C, for completion of the egg, larval, pupal, and egg-to-adult stages, respectively. The number of larval instars was determined by using head capsule widths that ranged from 0.31 - 2.68 mm. Clear distinctions of head capsule widths could be made from instar 1 to 3, yet overlapping occurred from instar 4 to 6. No distinction could be made between instars 7 and 8 in terms of head capsule width. All successive instars, except for instar eight, increased in size according to Dyar’s ratio. The effect of temperature on reproduction of B. fusca was studied at 15, 20, 26 and 30 ± 1 °C, 70 ± 30 % RH with 14L: 10D photoperiod. Oviposition occurred at all the temperatures evaluated, but no fertility was recorded at 30 °C. The total number of eggs laid by B. fusca females was 300 - 400 eggs and the optimum temperature for oviposition and fertility was determined to be between 20 and 26 °C. Results from this study on the thermal constants and lower and upper threshold temperatures of B. fusca can be used to predict the impact of climate change on the distribution and population growth of this pest. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

Busseola fusca is an indigenous lepidopteran pest species in tropical Africa, attacking several grain crops. Crop loss caused by this pest can be as high as 100 % depending on conditions. Despite it being a major pest in Africa, occurring in contrasting climatic zones, only a few studies have been published on its developmental biology. The effect of temperature on the development of B. fusca was studied at five different temperature regimes namely 15, 18, 20, 26 and 30 ± 1 °C and 70 ± 30 % relative humidity (RH) with 14L: 10D photoperiod. The number of instars for B. fusca was also determined. The most favourable temperature as well as the upper threshold temperature for larval development was found to be between 26 and 30 °C. Total development period was 152.6 to 52.6 days, respectively, at 15 °C, and 26 - 30 °C. The thermal constants for B. fusca was 99.50, 536.48, 246.25 and 893.66 °D and lower temperature threshold was 10.36, 8.14, 8.99 and 8.84 °C, for completion of the egg, larval, pupal, and egg-to-adult stages, respectively. The number of larval instars was determined by using head capsule widths that ranged from 0.31 - 2.68 mm. Clear distinctions of head capsule widths could be made from instar 1 to 3, yet overlapping occurred from instar 4 to 6. No distinction could be made between instars 7 and 8 in terms of head capsule width. All successive instars, except for instar eight, increased in size according to Dyar’s ratio. The effect of temperature on reproduction of B. fusca was studied at 15, 20, 26 and 30 ± 1 °C, 70 ± 30 % RH with 14L: 10D photoperiod. Oviposition occurred at all the temperatures evaluated, but no fertility was recorded at 30 °C. The total number of eggs laid by B. fusca females was 300 - 400 eggs and the optimum temperature for oviposition and fertility was determined to be between 20 and 26 °C. Results from this study on the thermal constants and lower and upper threshold temperatures of B. fusca can be used to predict the impact of climate change on the distribution and population growth of this pest. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015