"Alpine" is a breed of goat.

Anything that meets breed standards for alpines can be called an alpine.
"French Alpine" equates to 'purebred' alpine. Has to do with level of registry per ADGA registration. Essentially, purebred can be traced back to original imports, with NO outcrossing in the line. I believe calling them 'french' is falling out of style, and they will now be called purebred by ADGA.
"American Alpine" means it the animal is at LEAST 15/16 alpine but there was outcrossing done at some point in the history. This was either to improve the lines or simply because new lines were not available locally. In closed purebred herd books, once you breed american you can never 'grade up' to 'purebred' status. That line will always remain in the 'american' herdbook.
With alpines, 'american' is not a derogitory word like it is with nubians. The alpine herd books were closed for purebreds too early, meaning you couldn't 'grade up' to purebred status nor were any new alpines imported, unlike with nubians which have a very large 'base' of genetics. Thus, lots of outcrossing was done with Alpines of a necessity. The average american alpine is GENERALLY better than an average french alpine, probably because american is much easier to find and thus more people are working wth them. If more people are working with them, it's easier to find a new buck to use or places to get replacement stock.
In breeds like Sables and LaManchas, the purebred herd book is open - if you have an animal that is 15/16 Sable, she is 'american'. If you breed her to a purebred sable, her offspring are considered purebred as well. (correct me if I"m wrong on this one, sable/Lamancha breeders, this is just how I understand it!

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