Yes, if a mammal (or fish) is agitated, afraid, startled, or otherwise psychologically disturbed, its body automatically starts to convert the carbohydrate glycogen stored in its tissues into sugar for quick energy. This natural biological reaction gives the animal greater strength to fight or take flight, thus increasing its chances for survival. However, should the animal die, any conversion that occurred will shorten the meat's storage life. After death, the glycogen remaining in the muscles converts into lactic acid, a substance that retards bacterial growth. It follows that the lower the glycogen level, the less lactic acid is produced, and therefore the shorter the amount of time the meat will stay fresh.

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