Seasonal Hair Follicle Cycle of Camelus dromedarius

This experiment was conducted to identify the annual changes in hair follicle activity, changes at the follicular level and to characterize some of the fibre-follicle characteristics of camels at different ages. A total of 28 camels were allocated at random on the basis of age to one of four groups (2, 4, 6 and older than 8 years). All groups of camels were fed a maintenance level of ration throughout the experiment. To determine hair follicle cycle and other follicle characteristics samples of skin were taken using a trephine from the right midside of animals at approximately 28 day intervals for a period of 12 months. Using a small hand clipper, 15 g of fibre sample was taken from the left midside region to determine fibre characteristics. Analysis of variance was performed using a one-way SAS package and the means and the standard deviations of means were generated with this program. Mean S/P ratio, primary and secondary and total follicle densities of all groups of camels were 6.85±0.75, 3.76±0.63, 22.29±3.57 and 25.33±3.85, respectively. Mean fibre diameter, percentage of medullated and non-medullated fibre and clean wool percentage of all groups were 18.98±1.64, 18.10±1.65, 81.89±6.98 and 77.58±4.58, respectively. Mean percentage of active primary follicles significantly (p<0.05) decreased to lowest in February to a minimum of 83.1%, then significantly (p<0.05) increased over spring. Secondary follicle activity decreased over winter and spring to a minimum of 60% in February.