Because by then they should be hormonally mature even if not fully structurally mature. I don't read much research - I follow experience !
Ideally, not at all, but if they MUST be spayed, then let them grow up first.
INFORMATION about Dog's Health
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Hi Everyone,
Here is some great information for you all.1:- What to feed PREGNANT Dog.
Have a look at it http://newfieworld.net/blog/pet_tips/what-foods-should-you-feed-a-pregnant-dog2:- How to TRIM your Dog's Paws.
4 easy steps are here http://newfieworld.net/blog/pet_tips/four-4-easy-steps-on-how-to-trim-your-newfoundlands-paws-clean-paws-mean-happy-healthy-pawsHope you will like the information.
Regards.