A comparison of the nutritional value of organic-acid preserved corn and heat-dried corn for pigs

Three experiments were conducted to compare the digestible (DE) and metabolizable energy (ME) content (Exp. 1), as well as the apparent (AID) and standardized (SID) ileal digestibility of amino acids (AA) (Exp. 2) in organic-acid preserved and heat-dried corn. In addition, the performance of weanling pigs fed diets containing the two corns was compared (Exp. 3). In Exp. 1, 12 growing barrows (28.5±1.50kg) were randomly allotted to 1 of 2 groups and fed diets containing 970g/kg organic-acid treated or heat-dried corn to determine the DE and ME content of the two differently processed corns. The results indicated that the DE and ME of organic-acid treated corn were 16.6 and 16.3MJ/kg, which was greater than the 16.4 and 15.9MJ/kg, for the DE and ME of heat-dried corn (P<0.05 and P<0.01). In Exp. 2, 18 growing barrows (27.6±4.38kg), fitted with a T-cannula in the distal ileum, were allotted to be fed 1 of 3 semi-synthetic diets with 6 pigs per treatment. Two of the 3 diets were of similar composition to those used in Exp. 1 while the 3rd was a nitrogen-free diet that was used to measure basal endogenous losses of CP and AA. The results from Exp. 2 showed no significant difference in the AID or SID of CP and AA between the 2 corns. In Exp. 3, 60 piglets, weaned at 28day (7.34±1.243kg), were randomly allotted to 1 of 2 complete diets with 5 pigs per pen and 6 pens per dietary treatment for 4 weeks. Piglets fed organic-acid treated corn had 10.5% greater average daily gain (389g/day) than pigs fed heat-dried corn (352g/day; P<0.05). Feeding organic-acid treated corn significantly increased average daily feed intake by 12.5% (604 vs. 539g/day) compared with heat-dried corn (P<0.05). In conclusion, the available energy content of organic-acid treated corn was greater than heat-dried corn, and organic-acid treated corn improved weanling pig performance.