Avoidance was a pet talent located in the 3rd tier of all the pet talent trees. It was replaced by the pet talent Culling the Herd in patch 3.3.0, since Avoidance has been given as a passive treat to all player's pets, except Death Knights'.
Patch 3.3.0 (2009-12-08): This talent has been replaced by Culling the Herd. Hunter pets now innately take 90% less damage from area-of-effect abilities like all other class pets. This does not apply to area-of-effect damage caused by other players. Patch 3.0.2 (2008-10-14): Changed to pet talent. Gained an additional rank.
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Patch 3.3.0 (2009-12-08): This talent has been replaced by Culling the Herd. Hunter pets now innately take 90% less damage from area-of-effect abilities like all other class pets. This does not apply to area-of-effect damage caused by other players. 
