BCA

Well, to be frank, BCA if done properly and on a regular mode, is a full-fledged programme and doesn't really give time to pursue another course simultaneously.
If your questions is what 'else' can be done alongside to make the most out of BCA, then you may read the below text:
1. Internship- There is a summer internship component in most BCA programmes and students are graded on them. Take this very seriously. You may not get the exact profile you aspired for but it is a great way to get an exposure to the functioning of an organisation. Both startups and MNCs have different dynamics, so try to assimilate whatever you can.
2. Learning enhancement certifications- Aptech, NIIT, etc. offer some programming and networking certifications- Java, PERL, SQL, R, Python, C+ to name a few. Join a certification based on your areas of interest and make it a talking point on your resume.

Completing BCA and doing a course in animation has no relation in-between.
While BCA is related to programming logic, maths, calculations etc (Science). The animation is something related to ART. I am not sure why you are thinking of doing a course in animation (better job/career prospects or your interest/inclination).
One thing I will advise is, if you are planning for anything related to arts you should have a strong liking for that art, else you will never succeed or enjoy what you are learning or have learned. So, if you are naturally inclined towards art and think animation is something that really excites you, then you should definitely go for it.