It depends which ability it is. Some are activated and some are passive. The passive for animal taming is boarding, which gives you more stable slots.@Kyronix
I assume the mastery spells are optional and not always active? The "combat training" taming one specifically. I hope so! Else it will cause real balance issues between tamers and non tamers in the Europa (Battle)Chicken League!
Everything else is pretty awesome looking though. Really looking forward to this expansion. Did I read someplace there is new clothing and hair options too?