Fibre shedding and the effect of follicle cycle on quantity and quality of one humped camel fibre of Semnan province.

This experiment was conducted to study the effect of follicle cycle on the extent and timing of fibre shedding in Semnan province. 28 female camels were randomly divided into 4 groups of 2, 4, 6 and 8 years of age and were kept on a maintenance ration for a period of one year. To determine follicle characteristics, skin samples were taken from the right midside of camels ever month for a period of 12 months using trephine. Samples were fixed, dehydrated, blocked and stained using Sacpic method. Histology of skin structure and primary and inactive primary and secondary follicles was studied and follicle characteristics such as secondary to primary follicle ratio, primary and secondary follicle density (mm2) and the percentage of inactive follicles were determined. Statistical analysis was done using SAS package system and the means and standard deviations of means were estimated using Duncan's new multiple range test. Histological studies indicated that camel skin is composed of two main layers of epidermis and dermis but these layers are thick and by this means they can withstand heat stress. Microscopic examinations of transverse skin sections at sebaceous gland level indicated that fibre and inner root sheath structure were disrupted first and were finally lost from the follicle. At the end of winter and the beginning of spring follicle activity was reduced and resulted in fibre shedding. Primary and secondary follicle activity in mid-winter started to decline and reached a minimum in the beginning of spring and began to increase afterwards. Approximately about 40% of secondary follicles and 17% of primary follicles changed from anagen (active) to telogen (inactive) phase of follicle cycle and remained as such through the spring season. Results indicated that S/P ratio, primary follicle density, secondary follicle density and total primary and secondary follicle density was 6.85±0.75, 3.76±0.63, 32.29±3.57 and 25.33±3.85 respectively. The percentage of follicle groups with 3, 4, 5 and 6 primary follicles were 67.21, 21.54, 4.25 and 1.30 respectively. Mean secondary follicle density of 2, 4, 6 and 8 years old camels was 24.40±3.07, 21.39±5.43, 21.76±2.60 and 21.62±2.13 respectively. Mean total primary and secondary follicle density of 2, 4, 6 and 8 years old camels was 27.71±3.14, 24.68±6.00, 24.27±2.65 and 24.58±2.17 respectively. Fibre shedding started at the end of winter and continued in mid-spring. Bilateral Shedding started from the neck and spread ventrally to midside and back of the camels. Shed fibre ends formed club, brush, stepwise and thinned like structures. In terms of harvesting maximum weight of fibre, the optimal time for a single shearing for camels would be in winter season at the peak of follicle inactivity or before onset of shedding. At this time camels are in their poorest conditions for the cold weather and very limited feed availability and therefore it is possible that camels catch cold and die as a result. Use of combs during shedding season reduces further cashmere and animal loss. Subsequent shearing at the end of spring when weather is suitable provide a means of preventing fibre loss.