Post-natal development, dimensions of the skin follicle population and birthcoat follicular origin in Barki and ⅜ Merino lambs

Abstract

In a study of two breed groups, coarse wool Barki and f Merino f Barki, data were obtained on skin histology from birth to the age of 1 year, birthcoat fibre type arrays and fibre-follicle relationship.The | Merino exceeded Barki lambs in the maximum S/P ratio, values of which were 3-40 and 5-64 obtained at 6 and 8 months in Barki and § Merino respectively.Internal diameters of primary follicles ranged from 39-0 to 64-7 and from 41-0 to 56-8 fim; those of secondaries ranged from J9-8 to 34-9 and from 22-6 to 33-3 fim in Barki and f Merino respectively.The ratio of primary to secondary follicle diameters showed high values in both breed groups; averages were 1-89 and 1-71 for internal diameter and 1-86 and 1-71 for external diameter in Barki and f Merino respectively.Birthcoat fibre type arrays were mostly saddle, only 8-3 % were plateau (P 3 ) in both breed groups.