Next to nil chance of getting anywhere near becoming a vet without the initial A level requirements to firstly get you to Uni. Then you have to actually be offered a place at a Uni.... and that's all before the very lengthy yeasr and years of training and then the final examinations to actually qualify! Becoming a vet is said to be harder than qualifying to become a GP - my GP actually qualified to become a vet but changed his mind!
You would also need to consider if you have the funds available to take you through Uni etc...
Mature students and graduates
To gain admission to a veterinary degree course mature students without a degree should hold good GCSE and 'A' level examination passes in subjects including chemistry, biology and physics/mathematics, or be able to produce evidence of knowledge to this standard in comparable examinations.
Graduate applicants would normally be expected to hold at least an upper second class honours degree in a related subject. With a relevant science degree, you may be able to complete the veterinary degree in 4 years, rather than 5 – consult the prospectuses of each of the veterinary schools to see what options may be available to you. Graduate entrants do not qualify for UK student loans to cover the tuition fees, although student loans to cover maintenance costs may be available.
Graduates and mature students may need to discuss their own particular qualifications and experience with the veterinary schools' admissions tutors