The Coefficient Of Variation Of Fine Wool Diameter (CVFD) Resource And Control Measures

Wool is one of the most important natural textile materials in china, is also an important source ofincome of farmers. There are many factors affect the quality of wool,wool fineness is one of the mostimportant factors, the wool fineness has correlation with breed and breeding management, difference ofwool fineness exist in different positions of the same sheep and different individuals of the same flock.Wool production actually is the process that constantly concentrates wool of different positions,different groups and different regions. From the statistics view, only the average of wool fineness cannot indicate the wool quality. We should use the average of wool fineness and Coefficient Variance ofFiber Diameter (CVFD) together evaluates the wool quality. At present CVFD parameters has not getenough attention in our country, the national compulsory standard <wool>only put the average of woolfineness as consideration index. Studies have shown that, The CVFD is reduced by5%each time,equivalent to the fineness decreases by1μm. That is to say, breeding, breeding managementtechnology can reduce the CVFD. The research of Wool fineness distribution of region, relationshipbetween CVFD and breeding history, age, positions and wool fineness, quantitative research ofclassification arrangement effect on CVFD are rarely in domestic。CVFD was the object of this research, wool samples were collected from Kunas stud farm，Baicheng stud farm，Wenquan stud farm, we analyzed the factor which may affect the CVFD, hope todevelop the technical measures to reduce CVFD. Results:(1) Analysis of10238fine wool samplesshows that, Wool fineness with a board range16μm~25μm. Without proper wool classification theCoefficient Variance of Fiber Diameter (CVFD) will become much higher after mixing.(2) Wool fromthe farms with long breeding history, usually the CVFD ranges from15%to20%,which constitutes alarge proportion, the result shows some relativity between the breeding history and CVFD, usually thelonger history, the lower CVFD.(3) Fiber samples taken form single sheep shows difference betweenpositions. Wool form shoulder and hip with better evenness, and fibers form shoulder thinner.(4)Analysis based on age and CVFD doesn’t show any obvious correlation.(5) No correlation was foundbetween wool fineness and CVFD, which means wool with larger fiber diameter could be good textilematerial.(6) Wool produced by modern management technique (testing-earmarking-mechanicalshearing-classification-package-inspection-batch mixing) usually with low average CVFDcompared with control group.(7) Wool classification have much more effect to CVFD than breedingand management, It should bring to high attention of national wool industry and put classification to thewool quality control system.(8) The national compulsory standard <wool>should be revised.