I have been breeding Syrian hamsters for over two years now as a hobby breeder in my area. I haven't come across this issue before but my new female has not come into heat for a week now. I check every night between 10-12pm, but still no results. I contacted the person I bought her from but claims there wasn't any males in her cage. She is around 4 months old currently so her age isn't an issue for her to stop coming into heat.
Has anyone else ran across this problem before?