The relationships between vaginal collagen, plasma oestradiol and uterine prolapse in turkeys.

Uterine and vaginal collagen content and plasma oestradiol concentration were measured in traditional, male-line and prolapsed male-line turkeys to investigate the higher incidence of uterine prolapse in the male-line strain. The effect of exogenous oestradiol on vaginal collagen and plasma oestradiol was also tested in the traditional and male-line strains. Vaginal collagen was significantly lower in the male-line compared to the traditional-line, while it was lowest in prolapsed male-line turkeys. Plasma oestradiol concentration was higher in the traditional-line than the male-line. No difference in plasma oestradiol concentration was found between prolapsed and non-prolapsed male-line turkeys. Administration of oestradiol for 7 days significantly raised plasma oestradiol concentration but had no effect on vaginal collagen. Decreased vaginal collagen content was associated with uterine prolapse and may predispose the male-line strain to uterine prolapse. There was no evidence from these results to support an involvement of oestradiol in uterine prolapse in male-line turkeys.