I know, it's four years too late but maybe someone will find this helpful
Meins is not a correct grammatical form. It's more used to say 'Meins!' meaning 'That's mine!'
So, the nominative case pronoun for all genders would be:
Mein (Hund m.), Meine (Katze f.), Mein (Haus n.)
Meine (Hunde m. pl.), Meine (Katzen f. pl), Meine (Häuser n. pl.) Since plural forms always get the pronoun 'die' it's the same as the feminine plural form.
Bein is an old word for bone, it's not used anymore. The more common word for bone is (der) Knochen.