vacs is just the snip so it is firing blanks wich will take ur jill out of season and castrated is when they have no balls as for castrated is iam not sure if they can take them out of season but iam not sure and for keeping all year long would depend on ur self some folk will use a vacs hob in with the jills all year long but i would still expect them too be dragging them about a fair bit if they were not seprated but saying this some 1 i know that has had ferrets for 30 odd years says he had no problems with not breeding them or knoking them out of season but every 1 too there own [bANNED T