Never heard of animal protein being linked to acne. Perhaps excessive fat/oil? Regardless, dairy is a known factor. Going for a ultra-low lactose whey, e.g. isolate, hydro, or hydro casein, may be enough to avoid irritation. Then again, going without for a month or so is no bad thing. I did it recently following gut issues and didn't fade away to a shadow. If only whey was so potent!