Main points:
- Chest is much deeper
- Longer torso
- Leg joints more pronounced, especially shoulder and knee
- Uhh... back hoof? Idk how to explain this but just compare the image
- Bigger head
- Neck should be a bit longer than I drew, but I ran out of room
- See where beak meets face. Also difficult to explain but compare image
- Wings would have to be much bigger for a creature this size
More minor stuff:
- Crow beaks are pretty long (compared to eagle beaks), keep in mind
- See feather groups in wing
- Feathers on mane should be strait, not... moppish
- There's nothing for those screws to be secured in, I'm not exactly sure what that would cause but certainly nothing good. Drew bones where screws are for reference/repositioning
Summary:
You have to understand something before you can draw it, look at references including
- skeleton
- muscle
- full (like you'd see in and ordinary photograph)
- range of movement