An experiment was conducted to determine the digestible energy (DE) and metabolizable energy (ME) concentrations in
nine sources of corn grains fed to growing pigs and to compare the energy values among their countries of origin. A total
of nine sources of corn grains including five sources of yellow corn from the United States (USY), two sources of yellow
corn from South Africa (SAY), and two sources of white corn from South Africa (SAW) were used. Nine barrows with an
initial body weight of 37.1 ± 8.6 kg were allotted to a 9 × 9 Latin square design with nine diets and nine periods. The DE
concentration in SAY (3347 kcal/kg) was greater (P < 0.001) than in USY (3269 kcal/kg), but was less (P < 0.001) than in
SAW (3436 kcal/kg) on an as-fed basis. Similarly, the ME concentration in SAY (3291 kcal/kg) was greater (P < 0.001) than
in USY (3209 kcal/kg), but was less (P < 0.001) than in SAW (3386 kcal/kg). In conclusion, the DE and ME concentrations
in nine sources of corn grains are different among their countries of origin.