چکیده : | هدف از این مطالعه ارزیابی خصوصیات کمی و کیفی پشم تولیدی گوسفندان منطقه هورامان بود. تعداد 200 نمونه از الیاف گلههای مختلف جمعآوری و مورد تجزیه و تحلیل قرار گرفت. صفات مورد مطالعه شامل قطر الیاف، طول الیاف، درصد الیاف حقیقی، درصد الیاف مدولائی مداوم، درصد الیاف مدولائی منقطع، درصد کمپ، درصد چربی و درصد بازده بود. دادهها با استفاده از نرم افزار SAS مورد آنالیز قرار گرفتند. اثرات جنس، سن و گله به عنوان اثرات ثابت برروی صفات مورد مطالعه برآورد شدند. میانگین حداقل مربعات صفات قطر الیاف 41/39 میکرون، طول الیاف 47/12 سانتیمتر، الیاف حقیقی 88/90 درصد، الیاف مدولائی مداوم 67/3 درصد، الیاف مدولائی منقطع 49/2 درصد، کمپ 59/3 درصد، چربی 9/1 درصد و بازده 75/68 درصد بود. نتایج حاصل نشان داد که اثرات جنس حیوان بر صفات قطر الیاف، طول دسته، درصد الیاف مدولائی منقطع، درصد بازده خیلی معنیدار (01/0>p) و بر درصد الیاف حقیقی و درصد الیاف مدولائی مداوم معنیدار بود (05/0>p) ولی اثرات جنس حیوان بر درصد چربی و درصد کمپ معنیدار نبود (05/0 p)، اما بر درصد الیاف مدولائی مداوم و درصد چربی معنیدار نبود (05/0
The objective of this study was to generate some basic information on the quantitative and qualitative characteristics of wool production in Hewraman region. A total of 200 fiber samples of indigenous sheep in the Hewraman were collected from a variety of flocks. The studied traits included fiber diameter (FD), staple length (SL), true fiber (TF) percentage, continues medullary fiber (CMF) percentage, interrupted medullary fiber (IMF) percentage, kemp (K) percentage, fat percentage and wool yield percentage. Data were analyzed using SAS software. Quality control and calculation of descriptive statistics for all traits were performed using the GLM procedure of the SAS statistical package. The fixed effects in the model were age, sex and herd. Estimated least square means for FD was 39.41µm, for SL was 12.47cm, for TF was 90.88%, for CMF was 3.67%, for IMF was 2.49%, for kemp was 3.59%, for fat was 1.9% and for yield was 68.75. Analysis revealed that FD, SL, IMF, TF, CMF and wool yield were significantly (P<0.05) affected by the sex of animals but no significant effect found for fat percentage and kemp (P>0.05). The age of animals on FD, SL, TF, IMF, K and wool yield were significant (P<0.01), but no significant (P>0.05) difference was observed for the CMF and fat percentage. The Difference between male and female animals is due to the differences in the level of their secretion of androgenic hormones. Correlation of the fiber weight with the fiber diameter and fiber length are positive and high, therefore, higher average of diameter and length of fiber in males are expected. Fixed effect of Age of animals in the model was significant for most fiber traits including: fiber diameter, fiber length, percentage of true fibers, interrupted medullary fiber percentage, kemp percentage, and percentage of yield(P>0.05). However, no significant effect (P>0.05) was observed for the continuous modulated fibers and fat percentage (P<0.05). Increasing of fiber length in mature individuals relative to younger animals is expected due to the natural development of body tissues and follicles in growing animals. Results showed that staple length decreased in the >4 years aged animals, mainly because of the reduction of skin follicle activity. The effect of herd was not significant for any of the traits (P>0.05) indicated that the studied herds were similar in structure and diversity for wool traits. This similarity is due to high rate of migration and sheep exchange among herds. Based on fleece characteristics, it can be concluded Hewraman sheep produce good quality carpet wool, i.e. medium coarse wool. This study indicated a wide variation in the wool characteristics of Hewraman native sheep fleece, which suggested that selection may be employed to improve wool yield and quality in these sheep breed |