I have recently read a few isekai manga where the MC is reincarnated as an animal so I am wondering if anyone has some recommendation of series.

Have so far read 2 series where the MC is a animal/magical beast

Kita no Toridenite and another that i cant remember the name of, but the second is where a guy becomes a white wolf and is adopted and is pretending to just be a big dog and not a legendary wolf magical beast.

You can also recommend a serie if the MC can transform into a animel or magical beast or partly into one like that in The Symbiotic Relationship Between a Panther and a Rabbit or +Anima

The closest one to your request:
After All, I Became a Crow
The Falcon Princess
The Tyrant's Tranquilizer
A Good Day to Be a Dog
Fukushuu wo Chikatta Shironeko wa Ryuu Ou no Hiza no Ue de Damin wo Musaboru
Just for a Meowment
Hans and Emily
Wanderful Days

Maybe?
Be for the Beast
The Wolf & Red Riding Hood
Yajuu Kanojo
Joou Heika no Pet
Kodoku na Tonakai
Luna

Also, it's not exactly what you're looking for, but how about checking works under "Animal's POV" and "Animal Leading Character/s" categories?

Is manhwa ok?

The Dungeon Master begins with the MC getting reincarnated as a magical beast of the lowest class.

lol brick shitter

The Lady and the beast (Hongseul)

Shirokuma tensei: Mori no Shugoshin ni natta zo Densetsu
I'm a Behemoth, an S-ranked monster, but mistaken for a cat, I live as an elf girl's pet