Research Article
Seasonal Hair Follicle Cycle of Camelus dromedarius
Animal Science Research Institute, P.O. Box 31585-1483,Karaj, Islamic Republic of Iran
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.