To begin, label the microscope slides with the date and identification details of the rat. Between 6:00 and 7:00 p.m. grasp the base of the female rat's tail with the thumb and forefinger while applying pressure from the other fingers onto the lumbar vertebra of the rat.
To collect vaginal secretions, moisten the cotton swab with saline solution. After lifting the rat tail, insert the tip of the swab gently into the vagina and roll it. Then, roll the swab tip across the slide.
And locate the cells under the microscope using the 10X objective. After recording the estrus cycle stage, place the female rat along with a male rat in the mating cage between 7:00 to 8:00 p.m. On the second day between 7:00 and 8:00 a.m.
if a copulatory plug is found at the base of the mating cage, examine the vaginal secretion smear of the female rat, as demonstrated earlier. If pregnancy is confirmed, isolate the female rat in a separate cage. On gestation day 20, replace the pregnant rat's cage with a clean one.
And place medical absorbent cotton in the cage. Supply sufficient water and food for seven days. And position the cage in a quiet location.
On the 21st day postpartum, distinguish the gender of the offspring rats. In females, the distance between the anus and the external genitalia is shorter than it is for males. Place the male and female offspring in two separate cages.
