Abstract :
Four genomic regions located on goat chromosomes 1, 2, 5 and 13 previously reported as
significant DNA regions harboring quantitative trait loci (QTL) for growth and fleece traits in
goat were considered as candidate genomic regions. The objective of conducting this study
was to determine whether there is evidence for association of growth traits and cashmere
yield in native Iranian Rayini goats with markers flanking these candidate regions. One
hundred and twenty kids from 6 Rayini bucks (20 half-sib offspring per buck) were used in
the present study. The six bucks and their offspringwere genotyped for eight microsatellite
markers flanking the candidate intervals. Body weights recorded on the kids were birth
weight (BW0), weaning weight (BW3) and weight at 6 months of age (BW6). Average daily
gains from birth to weaning and weaning to 6 months of age were computed based on
the values obtained for BW0, BW3 and BW6. Cashmere yield was also recorded for the
kids at the first, second and third year of age. QTL analysis in the candidate intervals was
conducted using the least squared regression interval mapping approach. Linkage analysis
indicated significant QTL for growth traits on goat chromosomes 1, 2 and 5 (chromosomewide
significance of P < 0.01). Three of the candidate regions located on chromosomes 2, 5
and 13 were linked to cashmere yield. QTL effect ranged from 0.8 to 4.3 in units of residual
standard deviation for different traits and families.
