Seasonal patterns of secondary fibre growth, moulting and hair follicle activity in Siberian and Icelandic X Scottish feral goats offered high and low levels of dietary protein

• Published in: Small ruminant research Vol. 16; no. 1; pp. 69 - 76
• Main Authors: Rhind, S.M., McMillen, S.R.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1995
• Subjects: breed differences; cashmere; dietary protein; Fibre; fleece weight; Goat; goats; growth rate; Hair follicle; hair follicles; molting; Protein; s p ratio; Season; seasonal variation; Hair follicle; Fibre; Goat; Season; Protein
• ISSN: 0921-4488; 1879-0941
• DOI: 10.1016/0921-4488(94)00035-6

In a 2 × 2 factorial experiment, patterns of primary and secondary hair follicle activity, fibre growth and moulting were measured throughout the year in goats of two genotypes (Icelandic x Scottish Feral (IF) and Siberian (S)) offered rations containing either 100 g CP and 3.0 g methionine and cystine/kg DM (low; L) or 180 g CP and 5.8 g methionine and cystine/ kg DM (high; H). Growth of secondary fibre commenced later ( P < 0.001) and ceased earlier ( P < 0.001) in IF compared to S goats. IF goats also had a lower growth rate ( P < 0.001) and weight of secondary fibre ( P < 0.001). The mean diameter of secondary fibre from IF goats was less than in S goats ( P < 0.001) and they had a shorter mean staple length ( P < 0.001). None of these measures of fibre growth was affected by dietary protein content. The secondary/primary follicle ratio was higher in S than IF goats ( P < 0.001). There was a positive association between ambient temperature and secondary fibre growth, even after accounting for differences due to date. It was concluded that differences in growth rate, the duration of the season of growth and fibre diameter resulted in differences in the total weight of secondary fibre produced.