This cute anthro sheep is known as Leggy Lambs, who got quite popular for being just a couple of seconds in a Droopy sketch (but we all know the reason as to why). While I coudn't find the artist name, I have the source in a NSFW place (e621), where I also found this:
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Combo Breaker
Dec 16, 2014 at 02:00PM EST
Combo Breaker
Dec 16, 2014 at 08:46PM EST in reply to