Excess histamine in animal flesh can contribute to fatigue and other symptoms such as post-nasal drip. Histamine accumulates after the animal is killed, as a byproduct of breakdown of protein by bacteria and yeast.
Anyone with leaky gut issues will absorb more histamine than normal so that can be an issue with consuming rotting flesh, along with various other factors.
F 5 ft 3. HW: 196 lbs. Primal SW (May 2011): 182 lbs (42% BF)... W June '12: 160 lbs (29% BF) (UK size 12, US size 8). GW: ~24% BF - have ditched the scales til I fit into a pair of UK size 10 bootcut jeans. Currently aligning towards 'The Perfect Health Diet' having swapped some fat for potatoes.