Hi everyone,

I am currently conducting a research using a model of ovariectomized rats to induce osteoporosis. I've carefully read and studied the literature before conducting this study and I'm pretty sure that we have been doing everything correct.

But for some reason, when we analyze vaginal smears on the microscope, we found that some of my Wistar Rats are still cycling (a small number, only 3 animals out of 48). They have been going through all the phases proestrus, estrus, metaestrus, and diestrus. It's been already more than 3 weeks since we performed the surgeries. Why is that happening? They shouldn't be cycling anymore since they do not have the organ that is the main source of estrogen.

I would appreciate if someone with experience in this model could try to answer me these questions. I would also be happy to give more information about our model if necessary.

Thank you so much.