Sikhs can eat meat as long as it's not halal.
I was curious about this as I always (probably incorrectly) think of Halal as somewhat equivalent to kosher. These two tidbits turned up, per Switcher's post and then explaining the difference between Halal and Jhatka.
"The Hukamnama (edict or clarification), issued by Akal Takht Jathedar (head priest or head caretaker) Sadhu Singh Bhaura dated February 15, 1980, states that eating meat does not go against the code of conduct (Kurehit) of the Sikhs; Amritdhari Sikhs can eat meat as long as it is Jhatka meat."
"Jhatka, or Chatka, (jhàṭkā IPA: [tʃə̀ʈkɑ]) is meat from an animal that has been killed instantly, such as by a single strike of a sword or axe to sever the head, as opposed to ritualistically slow slaughter (kutha) in the halal method (dhabihah)."
Certainly, one would think that instant slaughter is more humane, but I don't know if one is more hygienic necessarily. Morally (IMO) a humane a death as possible would be preferable.