To investigate coordination of dietary levels of
valine (Val) and
isoleucine (Ile) on carcass traits and meat quality in pigs, 72 of 73.8 ± 1.6 kg crossbred barrows were randomly divided into a 2 (0.31% vs. 0.65% standard ileum digestible (
SID) Val) × 2 (0.25% vs. 0.53%
SID Ile) factorial arrangement. As a result, high dietary
valine decreased
myosin heavy-chain (MyHC)-I
mRNA expression, pH24 h value, bound water amount (T21 peak area ratio), sarcoplasmic
protein solubility and water holding capacity (WHC) of meat (P < .05). Meanwhile, high dietary
isoleucine increased pH24 h value, sarcomere length (P < .05) and tend to decrease drip loss (P = .07). The significant interactions between
valine and
isoleucine were observed on backfat thickness, water distribution forms and myofibrillar
protein solubility (P < .05) of pork. High
valine diets undermined WHC of meat probably through decreasing pH24 h value and sarcoplasmic
protein solubility considering their significant correlations with drip loss.