629 resultados para Wool shearing
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It has long been known that English Cistercian monasteries often sold their wool in advance to foreign merchants in the late thirteenth century. The abbey of Pipewell in Northamptonshire features in a number of such contracts with Cahorsin merchants. This paper looks again at these contracts in the context of over 200 other such agreements found in the governmental records. Why did Pipewell descend into penury over this fifty year period? This case study demonstrates that the promise of ready cash for their most valuable commodity led such abbots to make ambitious agreements – taking on yet more debt to service existing creditors – that would lead to their eventual bankruptcy.
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Throughout the industrial processes of sheet metal manufacturing and refining, shear cutting is widely used for its speed and cost advantages over competing cutting methods. Industrial shears may include some force measurement possibilities, but the force is most likely influenced by friction losses between shear tool and the point of measurement, and are in general not showing the actual force applied to the sheet. Well defined shears and accurate measurements of force and shear tool position are important for understanding the influence of shear parameters. Accurate experimental data are also necessary for calibration of numerical shear models. Here, a dedicated laboratory set-up with well defined geometry and movement in the shear, and high measurability in terms of force and geometry is designed, built and verified. Parameters important to the shear process are studied with perturbation analysis techniques and requirements on input parameter accuracy are formulated to meet experimental output demands. Input parameters in shearing are mostly geometric parameters, but also material properties and contact conditions. Based on the accuracy requirements, a symmetric experiment with internal balancing of forces is constructed to avoid guides and corresponding friction losses. Finally, the experimental procedure is validated through shearing of a medium grade steel. With the obtained experimental set-up performance, force changes as result of changes in studied input parameters are distinguishable down to a level of 1%.
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To study the annual pattern of plasma melatonin and progesterone concentrations in hair [Santa Ines (SI)] and wool [Romney Marsh (RM) and Suffolk (SU)] ewe lambs kept under natural photoperiods at 21 degrees 59'S, 12 ewe lambs (four/breed) were used. For melatonin, blood samples were collected monthly throughout the year at the onset (17:00, 19:00 and 21:00 hr) and end (04:00, 06:00 and 08:00 hr) of the night, and for progesterone the samples were collected in the morning, two to three times a week throughout the year. Plasma melatonin concentrations at different times of the day changed according to the season. In diurnal periods (17:00 and 8:00 hr) no seasonal differences were observed but they became evident in the nocturnal intervals (21:00 and 4:00 hr) and transitional night-day (6:00 hr) times. The patterns of melatonin secretion were higher in winter and autumn than in spring and summer. The patterns of plasma progesterone secretion were affected by interaction between breed and season. There was no seasonal variation in plasma progesterone concentrations for SI females. The progesterone pattern for RM and SU females varied with season. The plasma levels were higher in autumn and winter than in spring and summer. At 21 degrees 59'S hair and wool ewe lambs showed the same annual pattern of plasma melatonin concentration while the annual progesterone profiles were quite different. For SI females this pattern was constant along all seasons and for RM and SU females this pattern was higher during autumn and winter than spring and summer.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Protein is one of the limiting factors in animal production, and the knowledge of protein requirements by livestock is crucial for the success of a commercial animal raising enterprise. Thirty-four castrated lambs, 17 of them F1 Ideal x lie de France wool lambs and the remaining ones were Santa Ines hair lambs, with homogeneous initial BW, were used in the experiment. Five animals from each genotype were slaughtered in the beginning of the experimental period and used as reference. Diets (D) were composed of concentrate mix (C) and Cynodon sp. c.v. Tifton 85 hay (R), combined in three different ratios: D1 =60CAOR; D2=40C:60R and D3=20C:80R. Animals of each group of three lambs, that showed simultaneously an initial BW of 20 +/- 0.14 kg at the beginning of the dietary regimen, were slaughtered when one of them reached 35 kg, what always happened to be the one fed with D1. Net requirements for BW gain in wool lamb, fleece-free, ranged from 101 to 110 g of protein/kg BW, and for hair lamb ranged from 1 10 to 118 g of protein/kg BW. Net protein requirements for wool production ranged from 634 to 642 g/kg of produced wool. Hair lambs presented a 7.8-9.5% higher estimated net protein requirements than wool lambs, according to BW and daily weight gain (DG). Total net protein requirements for Santa Ines and wool lambs, with 30 kg of initial B W and an approximate 200 g mean DG, were 48.5 and 45.4 g/day, respectively. Metabolizable protein requirements for Santa Ines and wool lambs, with 20 kg of initial BW and an approximate 200 g mean DG were 59.4 g and 76.5 -/day, respectively. Net protein requirements for wool production was 64g/100g of produced wool. Thus, under the conditions of this experiment, it is concluded that hair lambs showed a higher concentration of protein in the body, more efficient use of the ingested protein and a consequent additional BW gain when fed isoproteic diets as compared to F1 Ideal x Ile de France wool lambs. (c) 2006 Elsevier B.V All rights reserved.
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The objective of this work was to evaluate the total endogenous N losses, and protein and energy net requirements for maintenance in growing lambs. Thirty-four castrated lambs, 17 F1 Ideal X Ile de France wool and 17 Santa Inas hair lambs, averaging 20 +/- 0.14 kg BW, were used in the experiment. Five animals from each genotype were slaughtered at the beginning of the experiment and taken as controls. Diets (D) were composed of concentrate mix (C) and Cynodon sp. c.v. Tifton 85 hay (R), combined in three different ratios: D1 = 60C:40R; D2 = 40C:60R and D3 = 20C:80R. Animals of each group of three lambs, that showed BW of 20 kg at the beginning of the dietary regimen, were slaughtered when one of them reached 35 kg, what always happened to be the one fed with D1. Total endogenous N losses estimated for wool lambs were 250 mg N/kg BW0.75. For hair lambs, total endogenous N losses reached 324 mg N/kg BW0.75 . Hair lambs showed higher (P < 0.01) (29.9%) net requirements of protein for maintenance than wool lambs. In contrast, net energy (NE) requirement for maintenance was similar (P > 0.05) for both genotypes (74.27 kcal/kg BW0.75 per day), the average of the antilog of the two intercept values obtained from the estimated regression equations of heat production for zero metabolizable energy (ME) consumption. Further studies should be done to check if this trend is also true for metabolizable energy and protein in animals exhibiting BW gains in tropical region. (C) 2003 Elsevier B.V. B.V. All rights reserved.
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This work was conducted to evaluate food intake and digestive efficiency of temperate wool and tropic semi-arid hair lambs, according to different concentrate: forage ratios in diet. Twenty-four lambs, averaging 90 +/- 1.8 days old and a mean body weight of 20 +/- 0.69 kg, 12 of them wool lambs, F, from Ideal x Ile de France crossing, and 12 others pure Santa Ines hair lambs, were distributed into a four replication 3 x 2 factorial arrangement consisting of three diets and two genotypes. Experimental diets consisted of: D1 = 60% concentrate mix (C) and 40% Cynodon sp. cv. Tifton-85 hay (F), D2 = 40% C and 60% F, and D3 = 20% C and 80% F. D1 was formulated for a daily gain of 300g per animal. Increasing forage levels in diets resulted in linear reductions (P < 0.01) in DM, OM, CP, TCH and metabolizable energy (ME) intake, and a linear increase (P < 0.01) in NDF ingestion. Tropic semi-arid hair lambs had higher DM, OM, NDF, CP, and TCH intake than temperate wool lambs. Although there were no genotype effects in OM and GE coefficient of digestibility, hair lambs showed more efficient (P < 0.05) digestibility of DM, CP, NDF and TCH. Increases in forage levels of diets corresponded to a negative linear effect (P < 0.01) in the apparent digestibility of DM, OM, CP, TCH and GE, while apparent digestibility of NDF increased linearly (P < 0.01). Total endogenous nitrogen (fecal plus urinary N) for F(1) Ideal x Ilede France wool and Santa Ines hair lambs were, respectively, 182 and 312 mg/kg(0.75) per day. Thus, Santa Ines tropic semi-arid hair lambs showed to be more responsive than F(1) Ideal x Ile de France temperate wool lambs to low quality fibrous diets. (C) 2004 Elsevier B.V. All rights reserved.
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The aim of this study was to determine the variation of the temperature after shearing in sheep under dry and hot environment conditions and to compare the temperature changes with variation in cardiac and respiratory frequencies, ruminal movements and hydration status. Twenty Suffolk unshorn ewes were studied. Physical examination was performed in all animals three times a day at 7:00 AM, 1:00 PM and 7:00 PM, during 42 days (22 days before shearing and 20 days after shearing). The skin temperature was measured by infrared thermometer over several surfaces of the body. Data were submitted to analysis of variance, for comparisons between groups (shorn versus unshorn) at each time, and the significant difference was evaluated at level of P<0.05 by Tukey test. The respiratory frequency was statistically significant at all times. When air humidity was high, the respiratory frequencies were low. The thermal stress was clear in sheep of this study, reflecting marked changes in cardiac and respiratory frequencies and rectal temperature. The respiratory frequency was the parameter more reliable to establish a framework of thermal stress in the unshorn sheep, with values on average three times higher than those reported in the literature. The heart rate monitors the thermal variation of the environment and is also an indicator of heat stress. This variation shows the Suffolk breed is well adapted to hot climates. The correlation between the body surface temperatures with environment temperature and air humidity was negative, as explained by the effect of wool insulation, i.e. even with an increase in environment temperature and humidity, the body temperature tends to maintain a compensating balance. In the shorn animals, the correlation between skin temperature with environment temperature and air humidity showed that the skin temperature increases when the environment temperature increases. The increase in the environment temperature does not affect the body temperature of unshorn animals due the insulating effect of the wool. However, when environment temperature rises, the presence of the wool starts to affect the thermal comfort as the heat absorption is larger than the capacity of heat loss. In this study, the best thermal stress indicators were the respiratory frequency and rectal and skin temperatures. The temperatures of the skin measured at the perineum, axillae and inner thigh were considered the most reliable.
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Pós-graduação em Ciência Animal - FMVA