24,208 research outputs found

    The estimation of genetic parameters for growth curve traits in Raeini Cashmere goat described by Gompertz model

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    The objectives of this study were to describe growth curve of Raeini Cashmere goat applying the Gompertz growth model and genetic evaluation of growth curve-related traits including model parameters of A, B and K, inflection age (IA) and inflection weight (IW) under animal model. The data used in this study, collected in Raeini Cashmere goat breeding station from 1997 to 2009 and were included 12,831 body weights records measured at birth, weaning, 6-months of age, 9-month of age and yearling of age. The Pearson’s correlation coefficient between observed and predicted body weights was 0.98, which means that Gompertz model adequately described the growth curve in Raeini Cashmere goat. The estimated value for growth curve parameters of A, B and K were 17.97, 1.97 and 0.017, respectively. The weight and age at point of inflection were 6.63 kg and 52.94 days, respectively. Direct heritability estimates for A, B, K, IA and IW were low values of 0.14, 0.10, 0.03, 0.14 and 0.14, respectively. Low estimated values for direct heritability of the studied growth curve traits in Raeini Cashmere goat indicated that direct selection for these traits may not be useful in terms of achieving genetic change. Direct genetic correlations ranged from −0.76 (K-IW) to 0.98 (A-IW). Phenotypic correlation estimates were generally lower than the direct genetic ones and ranged from −0.30 (K-IW) to 0.69 (A-B and B-IA). IA and IW had high positive phenotypic (0.86) and genetic (0.99) correlations, implying IA and IW were highly correlated in terms of phenotypic and genetic effects. The studied growth curve parameters of Raeini Cashmere goat have shown low levels of additive genetic variation.info:eu-repo/semantics/publishedVersio

    The inheritance of fibre traits in a crossbred population of cashmere goats

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    AbstractGenetic parameters were calculated for fibre traits measured on patch samples taken at 5 months of age on a crossbred population of cashmere goats, comprising goats of Scottish feral, Icelandic, Tasmanian, New Zealand and Siberian origin. Within-strain heritabilities, fitting genetic origin as a covariable, were: live weight, 0·71 (s.e. 0·08), fibre diameter, 0·63 (0·07), diameter standard deviation 0·43 (0·08), logipatch cashmere weight), 0·60 (0·06), log(estimated annual cashmere production), 0·51 (0·07), and fibre length, 0·49 (0·15). Including between strain information increased these values to 0·74, 0·68, 0·45, 0·73, 0·67 and 0·57, respectively. Maternal effects for all fibre traits were negligible. Expressions were derived to relate cashmere weight to fibre diameter and length, using functional relationships between these traits. Logarithmic regressions showed cashmere weight to be proportional to diameter2'7, indicating that selection to reducefibre diameter will have a disproportionate effect on cashmere weight. Analyses of subsets of the data confirmed this and showed that correlated responses to selection can be accurately predicted by considering thefunctionally relatedfibre traits on the log scale.</jats:p

    Softness attributes of Australian cashmere

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    Cashmere is a luxury fibre regarded as being softer and more comfortable than other apparel fibres. Cashmere is rare. Total cashmere production represents less than 0.01% of the textile market. Processed cashmere is expensive. Specialised skills and equipment are required for processing cashmere. For such an expensive textile raw material, surprisingly little objective information has been published on measurable attributes of cashmere in the form used by spinners. This article discusses new information about the softness and other quality attributes of Australian cashmere. Comparisons are made between Australian cashmere and cashmere from traditional sources of supply

    Feltability of cashmere and other rare animal fibres and the effects of nutrition and blending with wool on cashmere feltability

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    Felting is a unique attribute of animal fibres used for the production of a range of industrial and apparel textiles. Felting can be an adverse attribute as a consequence of dimensional shrinkage during laundering. As there is little objective information regarding the feltability of rare animal fibres or the factors which may affect felting three investigations were undertaken. A survey (n = 114) of the feltability of cashmere from different origins of production, cashgora, quivet, camel hair, llama, guanaco, bison wool, cow fibre and yak wool quantified the large variation between and within these fibre types. Cashmere from some origins and cashgora produced higher feltball density than the other fibres. Different nutritional management of cashmere goats (n = 35) showed that cashmere grown by poorly fed goats had a lower propensity to felt compared with cashmere grown by better fed goats. A consequence of the progressive blending of cashmere (n = 27) with a low propensity to felt superfine wool (high fibre curvature) increased the propensity of the blend to felt, but when the same cashmere was blended with low curvature superfine wool, there was little or no effect on feltability. The mechanisms which lead to variance in feltability of these fibres were quantified with multiple regression modelling. The mechanisms were similar to those reported for wools, namely variations in the resistance to compression, fibre curvature and mean fibre diameter, with likely effects of fibre crimp form. It is possible to source cashmere and other animal fibres which have different propensities to felt and therefore to produce textiles which are likely to have different textile properties.<br /

    Variation in the whiteness and brightness of white Australian cashmere associated with farm of origin and fibre attributes

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    While white cashmere is preferred by processors, its whiteness and brightness is affected by country of origin, amino acid composition, nutrition and cashmere production of goats. This work aimed to quantify the factors which affect the whiteness and brightness of 36 batches of processed Australian white cashmere sourced from nine different farms. The cashmere was tested for tristimulus values brightness (Y) and whiteness, as measured by yellowness (Y-Z). Linear models, relating Y and Y-Z were fitted to farm of origin and other objective measurements. Mean attributes (range) were: mean fibre diameter, 16.9 &micro;m (13.9&ndash;20.4 &mu;m); fibre curvature, 45&deg;/mm (31&ndash;59&deg;/mm); clean washing yield, 91.3% (79.5&ndash;97.3%); Y, 78.7 (74.7&ndash;82.2); Y-Z, 11.9 (10.3&ndash;13.6). Farm alone accounted for 72% of the variation in Y and 65% of the variation in Y-Z (P &lt; 0.001). Once farm had been taken into account only fibre curvature (P = 0.003) was significant in predicting Y and only clean washing yield (P = 0.047) affected Y-Z. Neither the proportion of the fleece present as guard hair (clean cashmere yield) nor cashmere staple length was a significant determinant of Y or Y-Z. For each 10&deg;/mm increase in fibre curvature Y increased 1.3 units. For each 10% increase in clean washing yield Y-Z declined 0.9 units. Variations in Y and Y-Z among farms were probably related to differences in geographic and climatic conditions and were significantly correlated to cashmere production. The effect of clean washing yield was probably related to a reduction in suint content.<br /

    Indices for cashmere fleece competition and across farm comparisons: The role of staple length in identifying goats of higher cashmere production

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    A single focus on mean fibre diameter (MFD, &mu;m) as the definition of cashmere quality overlooks the effects of fibre length, softness and fibre curvature on cashmere processing, textile quality and consumer acceptance. Many farmers overlook the importance of cashmere staple length (SL, cm) in their fleece assessments. We aimed to determine the importance of SL in comparison with MFD when evaluating cashmere production and to identify how across farm comparisons of cashmere fleeces can be objectively undertaken. A sample of 1244 commercial cashmere fleeces from goats originating from many Australian farms was used. Least squares models, relating the logarithm of clean cashmere production (CCMwt, g) to MFD and SL, were fitted. Six years of data from the Australian cashmere industry between farm fleece competitions were analysed to determine the relation between CCMwt and MFD. In the research flocks, adjusting CCMwt of individual goats across farms for MFD only accounted for 2% of the variance, whereas SL accounted for 39% of the variance. The least squares additive model involving only SL was: log10(CCMwt)=1.570+0.06010&times;SL. Thus CCMwt was proportional to: 100.06010&times;SL=1.1484SL. It was appropriate to adjust CCMwt for SL by a factor 1/1.1484(SL-SL0) where SL0 is a standard SL of 7.5cm. The between farm index for cashmere weight equals: cleancashmerestaplelengthindex=2.823&times;CCMwt/1.1484SL. For industry fleece competitions, regression analysis indicated that there was no association between cashmere production and MFD (P=0.81), similar to the research data. Adjusting CCMwt for MFD in across farm comparison and fleece competitions appears to be ineffective. For farm comparisons and in fleece competitions it is important to assess cashmere SL. The use of the Clean Cashmere Staple Length Index will provide a more robust comparison of cashmere productivity between farms as it is an indirect indicator of desirable skin secondary follicle development. The results have application in development projects where obtaining a cashmere MFD test is costly or unavailable. &copy; 2013 Elsevier B.V

    Breeding goats for organic production in Germany

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    With only 120,000 females (year 2000), goat keeping is a niche activity in animal husbandry in Germany. Most of the goats (about 90%) are kept on part-time farms. The main reasons they are kept are as a hobby, for milk production and for landscape management; in many cases it is a non-profit oriented activity. There are estimates (no official statistics exist) that 20,000 goats are milked and 10,000 are used in landscape management to avoid shrub succession on protected biotopes. In the year 2000 10% of the goats (12,000) were kept on organic farms but not all for economic reasons. Because the dairy breeds in Germany (White and Brown German Alpine) are selected under intensive keeping conditions, breeding under the restrictions of organic farming is necessary to get adopted and high yielding flocks. This is even more true in the case of harsh environmental conditions in landscape management. The German breeds are not suitable for the needs while grazing on marginal biotopes. This paper will show some results of: · a ten-year breeding programme for more milk ingredients, fat and protein, in a flock of 30 mother goats on an organic farm and · the breeding programme of the “Witzenhäuser Landschaftspflegeziege WLZ” for the new purposes of landscape management

    Processing and quality of cashmere tops for ultra-fine wool worsted blend fabrics

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    This study has focussed on three main areas. First, an evaluation of the physical attributes of cashmere tops available to commercial spinners; second, the influence of processing variables on the efficiency of producing cashmere tops from raw Australian cashmere; and third, the influence of design of cashmere ultrafine wool blends on the fibre curvature of tops. Testing the physical attributes of cashmere tops from traditional and new sources of supply, was followed by statistical analyses based on factors of origin, processor and other determinants. The analyses demonstrated important processor effects and also that cashmere from different origins shows commercially important variations in fibre attributes. It was possible to efficiently produce Australian cashmere tops with Hauteur, tenacity, extension, softness and residual guard hairs quality attributes equivalent to those observed in the best cashmere tops. The blending of cashmere with wool resulted in a reduction of the mean fibre curvature of the blend compared with the unblended wool. The present work demonstrated that the fibre curvature properties of blended low crimp ultrafine wool tops were closer to the properties of pure cashmere tops than were tops made from blended standard high crimp ultrafine wool. The attributes of textiles made from the relatively rare Australian low curvature cashmere could enhance the marketability of both Australian cashmere and low curvature wool.<br /
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