The ritualistic color of the fabric of the clothes does not matter, nor does the environment or the rest of the symbols accompanying the deed. The ‘sacrifice’ (this is not really a sacrifice) of the life of another being for any immortal being is actually hurting someone else for the alleged benefit of the self (be it that entity’s favoring us or actually granting us powers), and so is black magic, short and simple.
There is no difference, in the essence of the ritual, between the religious practice pictured in here, and killing cats in satanic rituals, no matter how these religious people will attempt to explain it.
I have written that the mentioned action of ritualistic animal killing is not really a sacrifice, and I owe an explanation: A sacrifice is the action of the self (a religious example – Jesus sacrificed himself for the sake of mankind). These lambs, pictured in Israel and killed for religious purpose, are not going to be sacrificed, they are going to be killed.