SPIRITUAL MEANING:
Sacrifice is an important aspect of spiritual growth and signifies the renunciation of the lesser for the rewards of the greater. As a rule, sacrifice has two meanings. Firstly, it is to give something up and secondly to make something sacred or holy. When those two things are possible within a dream scenario we are prepared to give up our ego or individuality for the sake of something greater or more important than ourselves.PSYCHOLOGICAL / EMOTIONAL PERSPECTIVE:
There is usually some expectation of a forthcoming just reward (often spiritual) for having made sacrifices. There may be an element of deferred gratification in that we do not expect an immediate reward, except that of feeling good or knowing we have done the right thing. There is always an element also of giving up egotistic behaviour, which is no longer appropriate, and going with the flow of life.
EVERYDAY MATERIAL ASPECTS:
Sacrificing an animal in dreams suggests that we are aware that our lower, more basic instincts can be given up in favour of spiritual power. We have to be prepared to recognize our own human fallibility, but to give up extravagance. A sacrificial altar may appear, or it may just be a question of killing and cooking an animal ritualistically. If the animal is willing to be sacrificed, then we are ready to transmute instinct into spiritual energy. If the animal is a hare or a rabbit, the symbolism is that of rebirth.
"You might also like to consult the entries for Animals, Hunt/Hunting/Huntsman and Rite / Ritual. "
Source: magical-poetry.blogspot.com
