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Fleece traits have an economic importance in sheep, and they are influenced by fiber traits. The age of sheep and body region which samples are taken have an importance on the traits studied. The study involved 24 Awassi ewes aged 3 to 6 years at college of Agriculture region. To study the effect of age and samples taken from different regions of the body (Shoulders, Back and tail) on some physical and chemical wool traits greasy fleece weight, clean fleece weight, clean wool percentage, staple length, fiber length, crimps, wax percentage and determination of wool pH. Data were subjected to statistical analysis using General liner model (GLM), (SAS) program . The results revealed a significant (p ≤ 0.05) effect of age on staple length 11.694±0.536, 9.472±0.445, 10.083±0.480 and 10.227±0.503cm on for the ages 3, 4, 5, 6 years respectively. with no significant effects on other traits . There was a highly significant. (P ≤ 0.01) effect of shoulder region on crimps and wool pH 1.640±0.065, 1.581±0.079, 1.332±0.050 crimp / cm and 10.297±0.433, 9.417±0.120 , 10.145±0.55 respectively.

The rate of sensible heat loss from a Clun Forest ewe was studied at several fleece depths in a temperature-controlled chamber. A simple resistance analogue was used to describe the heat flow from different body regions. Heat loss from the trunk depends largely on the mean fleece depth î . The fleece resistance was about 1.5 s cm -1 per centimetre depth. Heat transfer through the fleece was accounted for by molecular conduction, thermal radiation and free convection. The fleece conductivity k̄ b attributed to free convection depends on the mean temperature dif­ference ( T ¯ st — T ¯ ct ) across the fleece according to the relation k̄ b = 8.9 ( T ¯ st — T ¯ ct ) 0.53 . Estimates of the sensible heat flux from the trunk at environmental temperatures, T a , between 0 and 30°C range from about 8 W ( î = 7.0 cm, T a = 30°C) to about 160 W ( î = 0.1 cm, T a = 0°C). In contrast, the sensible heat loss from the legs depends mainly on the local tissue resistance. For environmental temperatures between 0 and 30°C, the calculated tissue resistance for this region of the body varied from about 8 to 1 s cm -1 . The corresponding heat loss from the legs was between 10 and 20 W, compared with between 3 and 7 W from the head. The fastest heat loss from the legs occurred at an environmental tempera­ture of about 12°C. Although the proportion of the heat loss from the extremities depends on environmental temperature, the total heat loss (sensible or latent) was closely related to the mean skin temperature of the trunk.

This study was conducted to investigate the variations in clean wool yield percentage among body regions and the relative reliability of each clean yield of 8 regions for predicting the clean yield percentage of the entire fleece of the Japanese Corriedale sheep. The animals examined were 10 Corriedale yearling ewes born in the spring of 1954 in the chugoku Stock Breeding Farm of the Ministr of Agriculture and Forestry. The clean wool yield percentages of small wool samples taken prior to the shearing time at 13 to 14 months after birth, from each sheep in 8 body regions including withers, back, rump, shoulder, side, hip, belly and thigh, were compared with one another and with the clean yield percentage of the entire fleece.The results obtained are as follows.1. Higher clean yield percentages were obtained from the withers (55.42%), back (52.55%), rump (52.62%) and shoulder (52.44%) and lower percen tages from the side (50.94%), hip (51.60%), belly (51.05%) and thigh (49.58%).2. The mean clean yield percentage of the entire fleeces (47.33%) was lower than that of any one of the 8 body regions.3. The difference in the clean yield percentages among the individuals and among the regions was highly significant and the difference among the individuals was greater than that among the regions.4. Correlation coefficients between the clean yield percentages of small wool samples from the 8 regions and those of the entire fleeces showed different values among the body regions; higher coefficients were obtained from the rump, thigh, hip, belly and back and no significant coefficients from the withers, shoulder and side.5. From the results of the present study it seems that among clean wool yield percentages of the small wool samples from the back, rump, hip, belly and thigh, differences in accuracy for prediction of clean yield percentage of the entire fleece are so small and clean wool yield, percentage of each of these five regions would be adequate for use in predicting the clean yield percentage of the whole fleece.

Light-microscope studies reveal distinctive features in the hair- and woolgrowing skin of adult sheep. The epidermis is variable in thickness-usually thin on wool-growing regions and thicker on haired regions. The follicles are mostly in groups containing one, two, or three primary (P) follicles and a number of secondary (S) follicles. The SIP follicle ratios vary from zero to about 30, depending on the breed and body region. The capillaries, myoepithelium of sweat glands, and dermal papillae of the follicles are often reactive for alkaline phosphatase. This enzyme is also asymmetrically distributed in some follicle bulbs and here it might be related in some way to the segmentation of the fibre cortex and perhaps to the formation of crimped wool. The dermal and follicle nerve networks contain cholinesterases. The latter may also contain alkaline phosphatase. Encapsulated end-organs and tactile disks are occasionally present in both hair- and wool-growing skin. Melanocytes, most common near the dermo-epidermal junction, may also be present in the outer root sheaths of the follicles, sebaceous glands, sweat glands, and dermis. Acetylcholinesterase-positive branched cells are invariably present in the epidermis in all regions where there are follicles. Sebaceous glands are associated with all follicles and apocrine sweat glands with the P follicles only. The P follicles also possess erector muscles that react for cholinesterases. Both the subaceous glands and sweat glands are usually larger in haired regions than in wool-growing regions. Large "eccrine" glands open on the naked part of the muzzle.