Research in animal embryology is centered on unlocking the mechanisms that control the formation of complex animal organisms from developing embryos. For zoologists, it is the academic parallel of plant embryology.
A basic first course in animal embryology will cover the general topics listed here:
There are some good online tutorials in animal embryology. Check out the ones at University of Wisconsin-Madison and University of New South Wales. A great list of books on human embryology can also be found on the University of New South Wales website. An excellent book on veterinary embryology is available at Amazon.com.