Quote Originally Posted by Gottimhimmel View Post
Now for the second part of my question: If masculine animate nouns take the genitive ending in the accusative, are all animals that have a masculine ending animate? And are all animals, masc or fem considered animate, but the feminine in the accusative just looks the same as the nominative?
I'll answer the second part

1. All animals are considered animate regardless of there ending.

2. The feminine accusative never looks the same as the nominative since the feminine accusative has its own special ending:
река (river) - реку - inanimate;
сестра (sister) - сестру - animate (person);
собака (dog) - собаку - animate (animal).

The only exception are the feminine nouns which end in -ь:
ночь (night) - ночь - inanimate;
дочь (daughter) - дочь - animate (person);
мышь (mouse) - мышь - animate (animal).