Determinants of permanent first incisor eruption in grazing Australian Angora goats

Objective: To investigate the effects of live weight, sex and other factors on deciduous (first incisor) loss and permanent first incisor development in Angora goats. Design: Goats were part of a pen study on the effects of energy intake in Angora does during pregnancy and lactation on kid growth and development. The design was three levels of nutrition in mid-pregnancy × two levels of postnatal nutrition in 17 randomised blocks. Methods: Conception times were calculated by using artificial insemination, with ultrasound examination 43 days after insemination. Does were fed different amounts of a formulated diet in their pens. After weaning, goats were grazed in sex groups. Deciduous first incisor loss and permanent first incisor development were recorded at 11 time points from 14 to 20 months of age. Results: For each sex, the time for visible eruption and full development of permanent first incisor declined linearly with increased live weight by 5.9 and 5.4 days/kg live weight, respectively. The time to reach similar development stages for first permanent incisors eruption was 3 months longer for the lightest animals compared with the heaviest animals. Date of birth, birth weight, doe age, growth rates, mid-pregnancy and postnatal nutrition, parity, day of weaning and weaning weight had no detectable effect. Conclusions: The results explain much of the substantial range in reported first permanent incisor eruption dates for small ruminants and have application in ageing of goats, marketing of kids for meat, in the selection of animals for breeding flocks and in educational material.

Beyond mimesis : place, interpretation and response

My study examines the subjective nature of artistic interpretation through the notion of mimesis as process or transformation of material. Influential factors that mediate in the artistic process, such as memory, reflection and an awareness of cultural analogy and metaphor, are examined and related to a specific project in the studio, where the mediation process is further influenced by the materials used to produce the images. My studies of the concept of mimesis have revealed an intermediary realm that exists in the space between empirical reality and its interpretation. Throughout history the process of mimesis has been integral to all forms of the arts. In Plato's time the production of an image that simulated things as they appeared to the eye was considered a desired ideal. Aristotle later introduced developments which extended this concept to include a refiguring or reforming of material derived from the original source, making new connections between existing factors and in this transformation bringing new meanings to a symbolically constituted world. This discussion of the representation of reality, the influence of a dialogue between notions of imitation and the recreation of material continues throughout the exegesis. My study emphasises the interpretive stage of the mimetic process where a consideration of these themes is most relevant and some of the factors that can influence its outcome. It is my opinion that the production of images in response to the particularities of place can be defined in three stages. Firstly, the experience of the place; secondly, the beginning and maturation of the idea or concept; where mimesis takes place, and thirdly, the production of the art work in response. This process is illustrated in Part 2 of the exegesis, where the development of the studio work is documented and linked with the themes discussed in Part 1. The geographic site or place I selected to study is adjacent to Mt. Noorat, a volcanic site in the Western district of Victoria; the surrounding plains are littered with scoria that has been thrown out of the volcano thousands of years ago. Early British, Scottish and Irish settlers to this region used the stone to construct fences reminiscent of their homeland, through this activity they cleared the land and confined and protected their stock. My interests are in factors that include - the material of the stone, notions of enclosure and safety, of boundaries and circumscribed space, and of the cultural reflection that has taken place in this reconstruction of Eurocentric vision. These walls also represent the means by which land was enclosed and property defined, moving from a situation of public access to notions of ownership and the annexation of land for individual gain. Around each point of eruption, the craggy volcanic scoria has been used to create a constructed landscape which both symbolises and mirrors the Anglo - Celtic origins of the people. I have used the legend of Narcissus to illustrate the self-reflective and introspective processes that the settlers invoked in their attempts to come to terms with a strange land. I consider that the story of Narcissus, who fell in love with his own reflection, finds a parellel in the creation of the walls. The re-creation of artifacts from their own cultural environment provided the settlers with a familiar 'face' in an alien world; a reassurance of the familiar in an unfamiliar terrain. Part of this study is an investigation of this notion of landscape as cultural reflection. Geographers have long known that landscape is a cultural construct, an historically evolving ideal manifested in painting, prints and drawings as well as poetry, gardens and parks. One can view these constructions as illustrations or images of meaning which constitute representations of cultural ideals. The neo-classical influence reflected in the paintings of artists who accompanied the early expeditions to Australia demonstrates these themes. The medium of the mirror provides the opportunity to suggest aspects of a cultural reflection and an awareness of identity that has relevance to contemporary Australian culture, therefore, I have allowed it to play a major role throughout this study. Its role in mimesis, firstly, as a reflection in an imitative sense is established, then in its refigurative role, in which the similarities between the original and the reformed rely more on correlative factors than representation. I have used examples from the history of art to illustrate this potential. The formation and development of a narrative involving reflection threads throughout the thesis, both in the visual presentation and in the exegesis. The production of a body of paintings, drawings and sculpture reflect my interpretation and response to the particular site. The correspondences between these works and my theoretical concerns is articulated in the exegesis. The metaphor implied by the use of the walls as agents of enclosure also refers to the capacity of the individual to be confined by notional boundaries and restrictive practices where totalising systems of thought dominate theoretical debate and restrict its freedom. I have used images where gaps in the walls represent the potential implicit to the concept of liminal space, where the spectator moves from one physical space to another and from one stage of development to another. The threshold of this opening in the walls becomes the site where transformation can take place, a metaphor for the mimetic process where the initial experience is translated and transformed into the final product. The paintings, drawings and other works in this series fulfil the role of marks on the surface of the mirror, separating the initial experience from the processes of memory, reflection and speculation. The works draw attention to the materiality that they represent and yet provide the opportunity for new insights and experiences, allowing the subjective nature of artistic activity to combine symbolic elements relating to the site, resulting in the production of meaning.

Evolution in a cold climate

A brief appraisal of marine fossils from high latitudes and episodically cold climate especially in east Australia and New Zealand during Late Palaeozoic and Early Mesozoic times shows patterns of evolution and survival that differ from those adduced for the palaeotropics and Northern Hemisphere. Examples taken from amongst phyla Scyphozoa, Bryozoa, Brachiopoda and Classes Bivalvia and Class Cephalopoda suggest these attributes:
1. Evolution and demise of species and genera proceeded at a rate close to that known for palaeotropical and Northern Hemisphere macro-invertebrates, but involved fewer families and orders.
2. Possibly, intraspecific variation was greater amongst southern palaeohemisphere Permian species than in those of the Permian palaeotropics.
3. There was no proven diminution of life at the end of the Guadalupian (Middle Permian) at southern high latitudes, where however the fossil record is meagre for this interval. Younger Wuchiapingian and Changhsingian faunas were moderately diverse.
4. There is no evidence for a high latitude Southern Hemisphere anoxic event in the Early Triassic despite claims of a world-wide anoxic interval. Nor has any substantial volcanic eruption or bolide impact left any marked traces in the sedimentary record.
5. As a consequence, some major groups such as Bryozoa and Conulariida (Staurozoa) survived the end- Permian extinction shock in the Southern Hemisphere.
6. Other major groups appear to have survived better in the south than in the north, notably, mollusc Bivalvia and Cephalopoda. It therefore appears likely that Triassic seas were restocked substantially from the Southern Hemisphere and that the Permian extinction shock was asymmetric with respect to latitudes in its distribution and affect.

Mohair research update 18 : the importance of the live weight of Angora goats on husbandry and production

The live weight of farm animals is strongly associated with production, profitability, management requirements and animal survival (Table 1). The mature live weight of farm animals and of goats is positively associated with their potential to grow rapidly. Live weight is directly related to the nutrient requirements of goats, irrespective of their productive state.

For Angora goats in particular, live weight is associated with mohair production and mohair fibre diameter, age at puberty, reproductive performance and ovulation rate, carcass attributes, meat production and sale value at the end of their productive life. Live weight also affects the timing of the eruption of incisor teeth.