19 research outputs found
Breeding for Resistance to Infectious Diseases in Small Ruminants
No full textLivestock Production/Industries,
Resistance to endoparasites in small ruminants: Genetic considerations
No full textThis paper focusses on within-breed genetic variation in resistance to endoparasites in the Australian Merino. It stresses possible differences in the Merino resistance, simply because of different history of management. The Australian Merino was introduced into Australia 200 years ago. It has almost entirely developed in that environment, i.e., it has been exposed to different methods of parasite control drenching, and there has been very little natural selection for resistance in this breed over recent years. However, the Australian Merino has been studied for over 20 years for genetic variation in parasite resistance. Genetic variation in resistance to endoparasites has been studied in five flocks in Armidale, and on flocks in New Zealand and Fiji. They were assessed using faecal egg count following artificial infection. The first flock includes lines of medium-wool peppins, and the others are based on fine and fine-medium Merinos. The work with these flocks showed that the heritability of resistance to endoparasites is measurable and that resistance is not genetically correlated with such production traits as fertility, body weight, fibre diameter and wool weight
Prospects of breeding small ruminants for resistance to internal parasites
No full textResistance to nematode parasites can be improved by selection, but efforts to include appropriate traits in commercial livestock breeding programs are only a recent development. Procedures for including resistance in breeding programs are similar to those involving other traits. The steps are described with special reference to sheep, and areas are highlighted where particular considerations exist. Three approaches are described and contrasted: breeding for resistance (reduced parasite numbers, as determined by faecal worm egg count); resilience (production during parasitism); or number of treatments required during parasitism. It is necessary, but difficult, to assess the economic benefits of improving resistance relative to other traits. Disease costs vary widely depending on the prevalence of the disease and on the availability, effectiveness and sustainability of alternative control measures. Costs of treatment and control are relatively simple to estimate for a given situation, but production losses are more difficult. Methods of dealing with this problem are discussed. Breeding for disease resistance usually requires that either selection candidates, or their relatives, are exposed to the pathogen so that resistance levels can be compared. Parasitic diseases generally create no special ethical problems in a breeding program unless natural challenge levels are insufficient to enable discrimination between hosts in their susceptibility. In the longer term, it is desirable that selection criteria for all major diseases be developed that will be informative in healthy animals. Molecular genetic markers offer promise, but simple genetic markers have so far been as elusive as physiological traits to predict resistance in undiseased animals. In the longer term, useful genetic markers will be found and techniques for combining these with phenotypic information need to be developed. Commercial breeding programes for sheep which include resistance to gastrointestinal roundworms are now operating in Australia and New Zealand, and issues related to breeding in the tropics are discussed
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Ecological vulnerability ::the law and governance of human-wildlife relationships /
No full textHumans are responsible for biodiversity loss in many related and sometimes conflicting ways. Human-wildlife conflict, commonly defined as any negative interaction between people and wildlife, is a primary contributor to wildlife extinction and a manifestation of the destructive relationship that people have with wildlife. The author presents this 'wicked' problem in a social and legal context and demonstrates that legal institutions structurally deny human-wildlife conflict, while exacerbating conflict, promoting values consistent with individual autonomy, and ignoring the interconnected vulnerabilities shared by human and non-human species alike. It is the use of international and state law that sheds light on existing conflicts, including dingo conflict on K'Gari-Fraser Island in Australia, elephant conflict in Northern Botswana, and the global wildlife trade contributing to COVID-19. This book presents a critical analysis of human-wildlife conflict and its governance, to guide lawyers, scientists and conservations alike in the transformation of the management of human-wildlife conflict
Anne Bronte's The tenant of Wildfell Hall: A feminist text?
No full textThe basic argument presented in this dissertation is that Anne Bronte's The Tenant of Wild/ell Hall can be interpreted as a nineteenth century 'feminist text', if we accept feminism as simply the advocacy of women's rights on the ground of the equality of the sexes.
Before attempting an analysis of the text itself as a 'feminist text' the dissertation first seeks to recognize and illuminate the problems apparent in claiming that any author writes authentically about women's experience, given that women's experience is never homogeneous, but it is always mediated by class, ideology, ethnicity, race, sex and the age in which the author lives. Chapter One endeavours to place the textual analysis into the context of feminist literary criticism to both demonstrate the complexity of the task and the intended approach to that task.
Chapter Two attempts to place the text into an historical context. This is done in order to illustrate the degree to which personal experience affected authorial intention, to show the manner in which feminist ideology in the text reflects notable contemporary feminist sentiment and to gauge public and critical response to the text.
Chapters Three and Four of the dissertation analyse the Gilbert Markham 'letter narrative' and the Helen Huntington 'journal narrative' respectively. In the 'letter narrative' Anne Bronte chooses to expose sexual inequality and feminine discontent in a typical patriarchal society through a satirical critique of an ostensibly idyllic rural community, represented by Linden Carr. Here she exposes a murky underside to professed communal and domestic felicity by showing the dissatisfaction of the female members and the disharmony between them which springs from a lack of fulfilling employment, except to cater to masculine needs and expectations. Helen Huntingdon creates a social upheaval at Linden Carr because she embodies feminine capability and independence, implicitly rejecting many of the small community's long-cherished shibboleths, which conveniently help preserve the patriarchal status quo. Helen also manages to elevate Gilbert Markham to an equal status with herself, thus allowing Anne Bronte to elucidate the qualities required in men to equip them for egalitarian marriage with women of lofty moral stature and independent ideals.
In the 'journal section' Anne Bronte launches a more vituperative attack on sexual double standards and the potential for masculine tyranny in marriage. In her attempt to expose sexual inequality, unsentimentally and unromantically, Anne Bronte also debunks the mythology surrounding the 'Byronic hero' and the 'Regency rake' simultaneously. Anne Bronte achieves this in a minute and 'realistic' description of the unmitigated iniquity of Arthur Huntingdon and his set of debauched companions. As a corollary to the exposure of masculine excess, Anne Bronte also illustrates a range of possible female response, concluding that a woman has the moral right to leave a thoroughly unsuitable husband. This is so particularly if the morality of the children of the union is equally in jeopardy with the wife's sanity and self-respect.
Throughout the text, Anne Bronte also appeals for equal educational opportunities for women and for more equitable child-rearing practices between the sexes. She spoke ardently for women's rights on the ground of the equality of the sexes without necessarily being a misogamist. She still revered the institution of marriage, provided it was a union of equals rather than the submission of one partner to the tyranny of the other
Sheep Updates 2006 - part 2
No full textThis session covers six papers from different authors:
GENETICS
1. Novel selection traits - what are the possible side effects?, Darryl Smith, Kathryn Kemper, South Australian Research and Development Institute, David Rutley, University of Adelaide.
2. Genetic Changes in the Australian Merino since 1900, Sheep Genetics Australia Technical Committee, R.R. Woolaston Pullenvale, Queensland, D.J. Brown, Animal Genetics and Breeding Unit*, University of New England, K.D. Atkins, A.E. Casey, NSW Department of Primary Industries, A.J. Ball, Meat and Livestock Australia, University of New England
3. Influence of Sire Growth Estimated Breeding Value (EBV0 on Progeny Growth, David Hopkins, David Stanley, Leonie Martin, NSW Department Primary Industries, Centre for Sheep Meat Development, Arthur Gilmour, Remy van de Ven, NSW Department Primary Industries, Orange Agricultural Institute
FINISHING
4. Predicting Input Sensitivity on Lamb Feedlot Profitability by Using Feedlot Calculator, David Stanley, NSW Department Primary Industries, Centre for Sheep Meat Development, Geoff Duddy, NSW Department Primary Industries, Yanco Agricultural Institute, Steve Semple, NSW Department Primary Industries, Orange Agricultural Institute, David Hopkins, NSW Department Primary Industries, Centre for Sheep Meat Development
5. Annual ryegrass toxicity (ARGT) in WA - 2006, David Kessell, Meat & Livestock Australia ARGT Project, Northam, WA
6. Poor ewe nutrition during pregnancy increases fatness of their progeny, Andrew Thompson, Department of Primary Industries, Victori
Sheep Updates 2006 - part 2
No full textThis session covers six papers from different authors:
GENETICS
1. Novel selection traits - what are the possible side effects?, Darryl Smith, Kathryn Kemper, South Australian Research and Development Institute, David Rutley, University of Adelaide.
2. Genetic Changes in the Australian Merino since 1900, Sheep Genetics Australia Technical Committee, R.R. Woolaston Pullenvale, Queensland, D.J. Brown, Animal Genetics and Breeding Unit*, University of New England, K.D. Atkins, A.E. Casey, NSW Department of Primary Industries, A.J. Ball, Meat and Livestock Australia, University of New England
3. Influence of Sire Growth Estimated Breeding Value (EBV0 on Progeny Growth, David Hopkins, David Stanley, Leonie Martin, NSW Department Primary Industries, Centre for Sheep Meat Development, Arthur Gilmour, Remy van de Ven, NSW Department Primary Industries, Orange Agricultural Institute
FINISHING
4. Predicting Input Sensitivity on Lamb Feedlot Profitability by Using Feedlot Calculator, David Stanley, NSW Department Primary Industries, Centre for Sheep Meat Development, Geoff Duddy, NSW Department Primary Industries, Yanco Agricultural Institute, Steve Semple, NSW Department Primary Industries, Orange Agricultural Institute, David Hopkins, NSW Department Primary Industries, Centre for Sheep Meat Development
5. Annual ryegrass toxicity (ARGT) in WA - 2006, David Kessell, Meat & Livestock Australia ARGT Project, Northam, WA
6. Poor ewe nutrition during pregnancy increases fatness of their progeny, Andrew Thompson, Department of Primary Industries, Victori
Plasma leakage in skin of sheep selected for resistance or susceptibility to fleece rot and fly strike
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