Cold enough to hold a carcass for a short time.
Food safety first: the danger zone is roughly 40-140°F (4-60°C). "Aging" only happens safely just above freezing. When in doubt, get it skinned, quartered and on ice.
Sources: Penn State Extension (40°F or below, two to three days at most) and NDSU Extension (aging at 34 to 37°F).
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