Opening the abdomen
By making a shallow cut at the top of the abdomen (by the back legs), you can insert your fingers in an upside down V shape (pointing downwards). Into the bottom of this V insert your knife shallowly and then cut downwards, keeping your first two fingers in place. This helps holds the stomach and intestines in place as you cut. If you don’t do this you can slice the guts open and the contents can taint the meat.