User blog comment:Wiryawan310/Unofficial Solution for Deformed Animal The Sims 3: Pets/@comment-50.99.162.127-20120321050213/@comment-3466295-20120321061107

I'd just try a google search for something along the lines of "deformed animals fix sims 3 pets". Other than that, make sure you have downloaded all patches as I think there might have been a fix in one of them, or get a better graphics card.