Variation in coefficient of total tract apparent digestibility of dry matter, nitrogen, and phosphorus and coefficient of total tract standardized digestibility of phosphorus in different corns fed to growing-finishing pigs

This study was conducted to determine the coefficient of total tract apparent digestibility (CTTAD) and coefficient of total tract standardized digestibility (CTTSD) of phosphorus (P) in nine corn sources fed to growing-finishing pigs. Ten barrows (initial of BW, 55.8 ± 3.0 kg) were individually housed in metabolism cages. Experimental diets consisted of nine different corns and one P-free diet for measurement of basal endogenous loss of P. Corn sources included 5 yellow-corns from the United States (USY-1 to 5), 2 yellow-corns from South Africa (SAY-1 and 2), and 2 white-corns from South Africa (SAW-1 and 2). Pigs were arranged in a 10 × 8 incomplete Latin square design with 10 diets and 8 periods. The CTTAD of dry matter (DM) in SAW-1 was greater (P < 0.01) than that of USY-3, USY-5 or SAY-2. Pigs fed SAW-1 showed greater (P < 0.01) CTTAD of nitrogen (N) than those fed USY-3, USY5 or SAY-2. The CTTAD and CTTSD of P across the nine corns averaged 0.43 and 0.49, respectively, but the values were not significantly different among the corn grains. In conclusion, the digestibility of DM and N varies in corn and needs to be determined to improve the efficiency with which the grain and corn based diets are utilized by growing pigs.