@italeigha
I've tagged this pamphlet before so you may wish to search the forum for the link which may still work.
https://my.puppyculture.co.uk/resources/flipbook/spay-neuter-booklet
It's full of facts and studies and Liz McCargo uses it as her reference.
There's a free read-only version if you'd search: PUPPY CULTURE SPAY/NEUTER BOOKLET.
Title page attached, if allowed.
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