After completing B.Sc in Zoology, you can look for M.Sc in Zoology/Applied Zoology. You can also try for courses in diverse areas like software or management. MCA degree is a good option for B.Sc students. If you have a flair for management, look for MBA or PGDM program. Short term courses in software offered by institutes like GNIIT or Oracle will be useful.

You can also go for job in government or private sector. 

If you are interested to make your career in Civil services then after completing Graduation you become eligible to apply for Civil services exam. This exam is conducted by Union Public Services Exam (UPSC) once in a year. Through this exam you can make your career as a IAS, IPS officer. You can also choose your career as a research scientist in agriculture and fisheries. There is huge demand of zoologist in Fish farms, leisure centres etc.

Good Luck!!