We have eaten no meat for several days.
I don't get how you get the meaning of "have not eaten for several days" from "しばらく肉を食べていない." I can only see it being "we will not eat meat for several days." If it means "have not eaten for several days" why isn't it しばらく肉を食べていなかった? しばらく with ていない makes sense in past and future tense, but I don't get how it works with the present tense.