Development of the reproductive system in turkeys with a high or low susceptibility to prolapse of the oviduct

Lines of turkeys selected for rapid growth and high meat yield have an incr eased incidence of prolapse of the oviduct compared with unselected or trad itional strains of turkeys. The development of the reproductive system and changes in plasma estrogen concentrations were compared in sire line and tr aditional turkeys with the aim of identifying any morphological or hormonal differences that could be associated with the high incidence of prolapse i n the male line. Four turkeys from each strain were killed weekly from 0 to 7 wk postphotostimulation, and samples from prolapsed birds were obtained from field cases. There were no differences in the rate of development of t he ovary, oviduct, uterus, vagina, sphincter ani muscle, or muscular cord o f the ventral ligament between the two strains that could predispose the si re line to prolapse. Histological investigation of the uterus, vagina, musc ular cord of the ventral ligament, and sphincter ani muscle 5 wk postphotos timulation in traditional, sire line, and prolapsed sire line turkeys did n ot reveal any differences that could be associated with prolapse. No prelay peak in plasma estradiol concentration was observed in either strain, and there was no evidence to suggest that plasma estradiol was higher in the si re line compared with the traditional turkeys. It was concluded that prolap se of the oviduct in sire Line turkeys was not associated with any anatomic al abnormalities or high plasma estradiol during reproductive development.