This is currently the dragon up the freeway when it comes to Minetest animal mods - a well polished work of art! Kudos to ElCeejo.
The animals themselves are well polished, have more behaviorial logic than any other mod not made by ElCeejo, and are really immersive!
The models stick to a consistent style which is asthetically pleasing and the textures go right along w/ the style to boot.
Sure, the mobs are going to end up being a bit robotic while walking around with nothing to do, but these are some of the least robotic mobs I've seen so far. Herding/Flocking behaviours stand out, as well as aerial predation (i.e. Owl)- I think they add a genius touch.
When you're dealing with all these behaviours, expect a bit of extra lag in return. This particular mod is pretty laggy for any public server, even with bird flocking nerfed :-)
However, it compares nicely with other mob mods like petz or mobs_animal per mob - These mods don't have even close to the amount of features animalia has, but don't optimize their code well enough to provide a significant lag differential, whereas animalia has pretty decent optimization. The (slight bit of) extra lag is worth it!