As FI said, only overseas Unis have courses for Vet science.
Local Unis only have courses for human Med.
Either way (ie. whether human Med or animal Vet), it is
recommended you go to a JC after your 'O' levels, and take H2
Maths, H2 Chem, H2 Bio and H1 Econs.
Or if you wish to keep your options for *other* Science courses
in the Uni open (eg. physics-based courses or engineering courses),
take H2 Maths, H2 Chem, H2 Physics and H1 Econs.
You can still take human Med or animal Vet with this
subject combi, but with a less number of Unis (since some
overseas Unis require both 'A' level Chem and 'A' level Bio
for such courses). But the advantage is a lot more Uni
courses will be open to you (when you take H2 Physics), should you
change your mind about your future profession.