It depends on the doe and how she was fed, if she was allowed to develop fat around the ovaries, and if she is narrow to begin with. I bred a holland for the first time at three years old and got 1 live kit out of five breedings. I bred a mini rex for the first time at 8 mos and she died. If the price is right, I'd try a 10 mos old, but wouldn't go past a year.
The rule, as I see it with everything I've read, is to stay under a year for first breeding with small breeds. 10-12 months is optimum. Anything after that, you possibly will have issues. I know there are cases where all went well with a older doe first time, but it seems they are far and few. Best bet, stay under a year.
I think I'll go ahead then. The other question I have is -- How do you tell if your Nethie is fat? I really can't tell, in photos of other peoples nethies they usually look pretty round- mine looks round too, but I don't know if that's how she's supposed to be or if she's just fat. I know with dogs, if you can't feel the ribs they are too fat- but how do you tell with a little rabbit?
I go by my rabbits spine. Willard is a true Netherland so he's my guide. If I can feel his spine, I know he's not fat. But if there is padding there and not feeling the spine, I know he's putting on weight. Can understand what you mean by being round and can't tell. That's why I had to research and this guide is what I found. Though he's just a pet, I don't want to let him lose his figure. Been like that with all my pets.