I know one friend who did the equine digestive system and I know some people who have done it about selective breeding (there’s a lot of very interesting content in this eg brachycephalics, urea breakdown in dalmations, syringomyelia in King Charles spaniels, the impact of the Kennel Club- the list goes on!) I think another person in my year did one on how animals can impact mental health.
Personally, I did one on women in medicine- it wasn’t very relevant to vetmed and became very history based and I wish I had done it on a vetty subject.
Just make sure it’s something you’re really interested in and there’s lots of links available- you’ll have to evaluate different ideas and go through the pros and cons of each one so I’m sure this won’t be a problem!
Best of luck (and well done for thinking about it early- don’t do what I did and leave it all until two months before the deadline...)