What to feed or what not to feed-that is still the question.

Introduction: This review addresses metabolic diversities after grain feeding of cattle using artificial total mixed ration (TMR), in place of pasture-based feeding.

Objectives: To determine how grain feeding impairs the deuterium-depleting functions of the anaplerotic mitochondrial matrix during milk and meat production.

Methods: Based on published data we herein evaluate how grain-fed animals essentially follow a branched-chain amino acid and odd-chain fatty acid-based reductive carboxylation-dependent feedstock, which is also one of the mitochondrial deuterium-accumulating dysfunctions in human cancer.