( Forages ( ( ( create ( more ( internal heat ) ) ) ( as ( ( the animal ) ( ( digests them ) ( than ( do ( ( ( grains and ) protein ) feeds ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Forages)) (VP (VBP create) (NP (RBR more) (JJ internal) (NN heat)) (SBAR (IN as) (S (NP (DT the) (NN animal)) (VP (VBZ digests) (NP (PRP them)) (SBAR (IN than) (S (VP (VBP do) (SBAR (S (NP (NNS grains) (CC and) (NN protein)) (VP (VBZ feeds))))))))))) (. .)))
Forages create more internal heat as the animal digests them than do grains and protein feeds.
(ROOT (S (NP (NNS Animals)) (VP (VBP engage) (PP (IN in) (NP (JJ internal) (NN digestion)))) (. .)))