Heat / spaying

[LEA HOROWITZ]

I have a six month female when can I expect her to go into heat
A friend has a nine month lab and the breeder told them ten to twelve months
Also how old should she be before spaying.

[Karen, Jasper and Jackdoodle]

It depends on the dog's adult size. Smaller dogs usually reach physical maturity earlier than larger ones. In the past, I've had two smaller females (20-30 lbs at maturity) who had first heats around 6 months old. A Labrador, being a larger dog, may not have a first heat until closer to a year, as your friend's breeder said. 

As to what age is best, ask your vet advice's on that. There is no single "right" answer, but the general consensus is that it's best to wait until their skeletal growth is complete, which is typically between 8 months and a year old for most doodles. (Sooner for the smallest doodles, later for the biggest ones).