Bedding types affect pubertal progression in rat

Method Twenty female Sprague Dawley rat (SD rat) were randomly divided into two groups according to their bedding types. The 1 group was raised in wood shaving bedding as a control and 2 one was in corncob bedding as an endocrine disrupting agent. Each group was checked daily for the first day of vaginal opening, and their vaginal smears were collected to determine estrous cyclicity after vaginal opening. The interval between vaginal opening and the first normal estrous cycle was recorded for determining sexual maturation. The phases of normal estrous cycles were as follows, proestrus, estrus, metestrus and diestrus. We compared the proportion of normal estrous cycles in each group.