School of Agriculture, Food and Ecosystem Sciences - Theses
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ItemThe effect of the level of nutrition during pregnancy and lactation on the production of grazing sheep, and the interaction between levels of fertility and nutrition( 1956)The livelihood of the sheep farmer depends upon the success with which his ewes produce and rear healthy lambs. This is of particular truth in those areas where fat lambs are produced. It is well known that the production of lambs in large number and in good health depends very largely upon the standard of feeding of the ewes during pregnancy and lactation. however in most areas of the world sheep are restricted to those marginal localities in which the agriculturist finds it difficult to produce milk, eggs or vegetables. Under these conditions, the feeding of pregnant and lactating ewes becomes a task of some difficulty. Where food is in short supply it is very necessary to know at what stage of pregnancy or lactation the plane of nutrition should be raised. Thomson and Thomson (1949) have shown that in Scotland the sheep farmer should feed a supplement to his ewes during late pregnancy. Coop (1950) on the other hand has shown that under his New Zealand conditions, the supplement was best reserved until lactation has commenced. It was thought important to know the effect of different planes of nutrition on pregnant and lactating ewes under the conditions of sheep farming in South Victoria. It was for this reason that the present investigation was undertaken. In addition it was thought to be of interest to determine the interaction "if any" between the level of fertility and that of nutrition
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ItemBark disorders and manganese nutrition of some fruit trees in the Goulburn Valley( 1961)Some Delicious apple trees growing in the Goulburn Valley and adjacent areas show "measles", an internal bark necrosis with elevated pustules distributed over the bark surface. Wood which is one or more years old is affected. The pustules increase in number and size as the disorder becomes more severe. In the cortex underneath the bark epidermis, necrotic spots are found in great numbers, being largest beneath the epidermal elevations. In severe cases, cracking and splitting of the bark occurs, mainly on older wood; the affected trees have fewer and smaller leaves than normal; twigs and limbs die back; and eventually the whole tree may die. Another bark disorder, known as "papery bark", is fairly common on Josephine pears in the Goulburn Valley. The symptoms are an internal bark necrosis with cracking and rolling back of the bark epidermis on shoots and twigs one or more years old. The symptoms of a further disorder, known locally as "leaf spotting are more severe on these trees affected with "papery bark", and in addition fruit on such trees or limbs shows more "russeting" than is normal. Die-back of shoots and limbs often follows. The cause of these nutritional disorders, "bark measles" on Delicious apples and "papery bark" on Josephine pears, was investigated. The analysis of fresh tissues showed increased amounts of manganese in leaves, fruit and, bark of affected apple trees and in the leaves, bark, buds and fruit of affected pear trees. To demonstrate that excess uptake of manganese was the cause of these disorders, hydrated manganese sulphate was injected into trees of healthy appearance showing low manganese content in their fresh tissues. After this injection, disorders similar to "bark measles" and "papery bark" were produced on apples and pears respectively. Soil acidification with chemicals in the field and soil waterlogging in pots also produced "papery bark" on pears, while soil waterlogging in pots produced "bark measles" on apples. Analysis showed increased amounts of soluble manganese in treated soils and in the tissues of affected plants growing on treated soils. Laboratory trials with soils from orchards, both healthy and with manganese toxicity (hereafter called "toxic soils"), showed that drying, heating and waterlogging, especially at temperatures of 20 degree Celsius or more, also contribute to the release of high amounts of soluble manganese. These trials showed the importance of moisture conditions and pH in the recovery of toxic soils.
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ItemNutritional studies of the young lamb( 1967)This thesis is based on original research work in a subject approved by the Faculty of Agriculture and is submitted under regulation 3.28 Section 6(a) of the conditions relating to the degree of Master of Agricultural Science. The experiments presented have been published in the Australian Journal of Experimental Agriculture and Animal Husbandry or in the Proceedings of the Australian Society of Animal Production. They were conducted while the author was a member of the Victorian Department of Agriculture which provided the facilities for this work. The first chapter of the thesis is a review of the literature on the digestibility of milk and solid food by the young ruminant - more specifically the calf and the lamb. The second chapter describes two experiments on the apparent digestibility of ewes milk and dried pasture by young lambs and the third chapter comprises two experiments relating to the effect of milk intake on the pasture consumption of lambs. The fourth chapter reports observations on the diet selected by grazing lambs in relation to older sheep. I was responsible for the design of this experiment, was actively associated with the field work and prepared the manuscript for publication. The fifth chapter is a paper on the effect of nutritional restriction during pregnancy on the reproductive performance of crossbred ewes and the subsequent growth of their lambs. The sixth chapter provides summaries of the experiments presented.
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ItemThe diet and helminth parasites of foxes, dingoes and feral dogs in Victoria( 1973)This thesis was prepared while the author was employed with the Victorian Department of Crown Lands and Survey at the Keith Turnbull Research Station, Frankston. It is in the form of three papers which describe the experimental work and a review of pertinent literature. The literature review outlines the extent of previous knowledge on the subjects of fox diet and fox parasites (helminth) in Australia. A short review of selected overseas studies is included. The experimental work deals with the incidence of various food items and helminth parasites in the gastro-intestinal tracts of foxes, dingoes and feral dogs collected in Victoria during the period from 1968 to 1970. The paper dealing with dingoes and feral dogs has been published (Aust. vet. J., 1972, 48 : 456-461) and the remaining papers have been submitted for publication. All funds for this research project were supplied by the Australian Meat Research Committee.
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ItemEffects of some management factors on sheep and wool production( 1970)It is difficult to be precise about the importance of the contributions made by the many people involved in this work. On a government research station and on private farms, field experiments inevitably involve many people. However, in each chapter presented in this thesis I made a major contribution in the planning, supervising and conducting of the experiment and in preparation of the results for publication. Where authorship has been shared, this is indicated at the beginning of each chapter. Some indication of the relative importance of contributions to this work is as follows:- Chapter I: The experiments were done on two sites, and at one of them Katamitite) I was directly responsible for the work. Chapters II, III: This work undertaken jointly with Mr. J.G. Bath, Chapters IV, V: This work was my responsibility. Chapter VI: The observations on sheep were my responsibility whereas those on pastures were the responsibility of Mr. J. Avery and Mr. I. Cameron. I prepared the manuscripts for chapters I to V and contributed to the preparation of that for chapter VI.