Silky overdue heat

Question
My Silky Terrier is 2.5yo she had her first heat at 9 months, her second 9 months later, and it has been 10 months since then and she doesn't even look like going into heat. We tried to mate her on her 2nd cycle and she wouldn't let the boy mount her, instead she was trying to mount him. We have since gotten another girl silky and she had her first heat at 6 months. Would having a 2nd female interfere, and is it a cause for concern if they miss a heat, Toni

Answer
Hi Toni,

I would have the female's thyroid and hormone levels check. A missed heat can mean that their levels are off.

Typically when you have a number of females they will regulate each other and go into heat at or near the same time.

You older female may be to dominate to allow a male to mount her and you may have to consider A.I.

Good luck.