Mazaher SAFDARIAN, Majid HASHEMI, Mohammad Reza HASHEMI

Characteristics of pelt follicles and their relationship with pelt quality in fat-tailed Gray Shirazy sheep

The purpose of the present investigation was to measure pelt follicle characters after birth and to determine the relationship among pelt and follicle characters in fat-tailed Gray Shirazy sheep. Skin samples were taken from 150 lambs at 1 and at 120 days of age and from their parents (18 rams and 150 ewes) using a biopsy punch (8 mm in diameter) from the right mid-side of the body. Several sections of 8 µm were then prepared, mounted, and stained on glass slides to determine follicle characteristics. The least square means of primary (P) follicle density/mm2 in skin of 1- and 120-day-old lambs were 14.6 and 7.1 for males and 15.4 and 7.0 for females, respectively. The least square means of secondary (S) follicle density/mm2 in skin of male and female lambs were 33.3 and 34.7 for 1-day-old and 21.7 and 20 for 120-day-old lambs, respectively. S/P ratios in 1- and 120-day-old lambs were 2.9 and 3.6 in males and 2.7 and 3.4 in females, respectively. There was no significant difference between sex of lambs for follicle density/mm2 of skin and S/P ratio in lambs of 1 and 120 days old. The correlation coefficient between 1-day-old follicle characters and final score of pelt was not significant, but for 120-day-old follicles it was moderate and significant. Correlation coefficients between pelt traits in newborn lambs were significant. Results indicate that although the density of follicles and the S/P ratio were moderate in fat-tailed pelt lambs, there was no correlation between them and the final score of pelt. Further studies are needed to determine whether other follicle characters like follicle curvature, follicle depth, and follicle group size would have a high correlation with final score of pelt to assess skin characters objectively.

Keywords:

Follicle characters pelt traits, correlation, Gray Shirazy sheep,

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