This seems to have changed a couple of days ago. 

The first time you click on the Breed-link, the males on the first page are listed from youngest to oldest. But if you browse to second page, the order gets switched the other way around: from oldest to youngest. Without touching that ordering-button in the upper right corner, that is. 

I don't think it should switch like that between pages. It's awfully disorienting. 

I'm having the same problem and I almost wound up breeding with the wrong male several times because of it.

Thank you for reporting. The sorting on breeding pages works in the same way now. Sorry for the inconvenience.