I know the fear of horses is : Equinophobia. but I am not sure there is one specifically for horse jockeys.
'Flogging a horse to death' means being obsessed with something. It is not a phobia.
If failing is your fear the name for the failing phobia (phobia mean fear) is atychiphobia.
Phobia means fear.
There is no official phobia name for the fear of vipers. However the official phobia name for the fear of snakes is ophidiophobia.
Necrophobia Phobia name for the fear of death. It is a common phobia
I don't think there's a phobia name for having a fear of hippos.But there is a phobia name that has the word "Hippo" in it: Hippopotomonstosesquippedaliophobia, which is the fear of long words (not fear of hippos).
I believe that the correct name of the phobia for fear of mice is musophobia
Hylephobia is the name of the phobia related to the fear of materialism
Ballistophobia is the name of the phobia related to the fear of missiles
Limnophobia is the name of the phobia associated with the fear of lakes
Traumatophobia is the name of the phobia relating to the fear of injury
Ideophobia is the name of the phobia relating to the fear of ideas