scholarly journals Cell Proliferation and Cortical Cell Production in Relation to Wool Growth

1979 ◽  
Vol 32 (3) ◽  
pp. 317 ◽  
Author(s):  
Patricia A Wilson ◽  
BF Short

The relationship of wool growth to cell proliferation in the follicle bulb and to the subsequent migration and growth of the fibre cortical cells was investigated in 10 Peppin Merino sheep. These sheep had been maintained on a low, medium or high level of nutrient intake to ensure a wide range in wool growth. The number and mitotic activity of the germinal cells in the follicle bulb were determined after administration of colchicine. Cortical cell size was measured following isolation of the fibre cells by acid-treatment of wool.

1994 ◽  
Vol 45 (6) ◽  
pp. 1171 ◽  
Author(s):  
GJ Lee ◽  
AJ Williams

Sheep from four Merino flocks, different in annual clean fleece production when grazed together, were offered a range of nutritional treatments to compare their ability to digest dietary organic matter (experiment 1) and to compare the relationships of wool growth and fibre diameter with nutrient intake (experiment 2). The sheep were selected from a finewool (Fl), a strong wool (S), and two medium-Peppin (MP6 and MP10) flocks. The nutritional treatments varied intakes of two pelleted diets-B and F. Diet B consisted of oat grain, lucerne chaff, and oaten straw, while diet F was as for B but fortified with fishmeal. The digestibility of both diets was negatively related to the level of intake, and there were some differences between the flocks in their ability to digest organic matter. Clean wool growth per unit area of skin was curvilinearly related (P < 0.001) to N intake, but was not influenced by diet per se. The regression coefficient for the relationship of clean wool growth with N intake and the estimated maximum wool growth rate of flock F1 were less than the other flocks. However, flock MP10 grew less wool than flocks S and MP6 at any given intake. Variation in (fibre diameter)2 accounted for 0.6 of the variation in wool growth, with responses in fibre diameter to intake being similar to those observed in wool growth. The responses in plasma cystine of the flocks to N intake differed, with the relationship for flock F1 being curvilinear and reaching a maximum at an intake of 27 g N day-1, while the responses of the other flocks were essentially linear. The relationships between plasma cystine level and wool growth differed between the flocks such that wool growth of sheep from flocks S and MP6 was more responsive to increased plasma concentration of cystine.


1992 ◽  
Vol 262 (6) ◽  
pp. S9 ◽  
Author(s):  
E Bowdan

Regulation of feeding is a fundamental element of homeostasis. This is reflected in the similarity of control mechanisms in a wide range of animals, including insects and humans. A close examination of feeding behavior can illuminate the physiological processes driving regulation. A simple, inexpensive method for recording fine details of feeding by caterpillars is described. Possible experiments, interpretation of the data, and the relationship of observations to the underlying physiology, are outlined.


1998 ◽  
Vol 44 (12) ◽  
pp. 1115-1136 ◽  
Author(s):  
M J Butler ◽  
A W Day

The relationship of polyketide melanogenesis molecular biology to that of nonmelanin-producing pathways in a wide range of fungi and other organisms is discussed. Analytical methods and fundamental properties of melanins are discussed and fungal melanin properties are compared with those of animal and bacterial melanins. The enzymatic degradation of melanins by lignin peroxidases is described.Key words: fungal melanin, polyketide melanin, DHN melanin, melanin degradation, melanin properties, melanin analysis.


Author(s):  
W.S. Green

This introduction to the symposium Inclusive Design and Usability gives an overview of some of the issues and problems facing ergonomists and designers who attempt to provide access to current technologies for a wide range of user groups, particularly those who may be considered disadvantaged or handicapped. The relationship of ergonomics and design is raised.


Author(s):  
Joel Altman

This chapter examines the use of ekphrasis in early modern theatre, with particular emphasis on its effect on the stage and the relationship of ekphrastic speech to the ongoing action in which it is enunciated. It maps the parameters of ekphrasis on the early modern English stage by considering a few examples of the ways in which ekphrasis instantiates early modern theatricality. It also discusses the expressive potential of ekphrastic speech and its transmission to the listener as well as the ironic uses of ekphrasis as a mode of persuasion, whether directed to oneself, an on-stage auditor, off-stage auditors, or all three. It argues that ekphrasis creates nothing less than what it calls ‘the psyche of the play’ and explains how the unusually flexible capacity of the staged word allows it to be used for a wide range of theatrical techniques, including the usual sense of ‘word-painting’. Finally, it looks at William Shakespeare’s deployment of ekphrasis in his work such asHamlet.


2010 ◽  
Vol 33 (1) ◽  
pp. 4.1-4.32 ◽  
Author(s):  
Richard B. Baldauf ◽  
Robert B. Kaplan

Applied Linguistics is a diverse field, comprising a substantial number of sub-fields, sub-specialisations and related fields. To see that this is the case one need only examine the various hand- books and encyclopaedic references that have been published in the last ten years to see the wide range of topics that have been covered. As with many professional areas in academia, Applied Linguistics is organised around national organisations, with its international structure being a loose confederation known as the International Association of Applied Linguistics (AILA). Given these diverse academic and structural arrangements, it should not be surprising if academics within different national associations were to cluster around different interests within the field. This study explores the question of what emphases are found in various parts of the world in Applied Linguistics, and in particular, the relationship of Australian Applied Linguistics to international trends using a structural text analysis of abstracts related to Applied Linguistics as well as an historical review of the trends involved.


Author(s):  
J. Creed ◽  
T.G. McEvoy ◽  
J.J. Robinson ◽  
R.P. Aitken ◽  
R.M. Palmer ◽  
...  

Superovulatory treatments for ewes are normally preceded by a period of priming. In a recent study involving two contrasting levels of feeding (0.6 versus 2.4 x maintenance), McEvoy et al (1993) observed that the higher level of feeding suppressed pre-ovulatory plasma progesterone concentrations and the subsequent early development and viability of fertilized ova. This finding suggests that there is a need to reconsider the recommendation, based on data for spontaneously-ovulating ewes, that ‘superovulated embryo donor ewes’ should be maintained on a high level of feeding during the period of oocyte maturation. It also raises questions regarding the form of the relationship between food intake and plasma progesterone concentrations over the wide range of feeding levels that occur in practice. The aims of the present study were therefore two-fold; firstly, to investigate the relationship between level of feeding and plasma progesterone for feed intakes that ranged from 0.6 x maintenance (M) to 2.4 M and secondly to assess the effect of pre-ovulatory feeding levels on the number, quality and viability of ova produced following superovulation.


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