Effect of corn hybrid and grain processing method on rate of starch disappearance and performance of finishing cattle

Two trials evaluated the effects of different corn hybrids on in vitro rate of starch disappearance and finishing cattle performance. Hybrids were selected, based on in vitro rate of starch disappearance (A = fastest, B = intermediate, C = slowest). In Trial 1, hybrids A and B were fed as dry-rolled and early-harvested, high-moisture (28%) corn and hybrid C was fed as dry-rolled corn. Cattle fed dry-rolled hybrid A gained faster (P < .10) and more efficiently (P < .10) than cattle fed dry-rolled hybrids B and C. No differences were observed in DMI, quality grade, or fat thickness among hybrids fed dry-rolled. Dry matter intake was lower (P < .10) and feed efficiency was improved (P < .10) for cattle fed corn hybrids A and B as high-moisture corn compared with those same hybrids fed dry-rolled. In Trial 2, hybrids A, B, and C were fed as dry-rolled and early-harvested, high-moisture (29, 28, and 29% moisture, respectively) corn. Performance and carcass measurements were not affected by hybrid fed. Cattle fed high-moisture corn gained faster (P < .10), consumed less DM (P < .01), and were more efficient (P < .01) than cattle fed the same hybrids dry-rolled. Across trials, hybrids, and processing methods, in vitro rate of starch disappearance was correlated with feed efficiency (r2 = .58, P < .001).(ABSTRACT TRUNCATED AT 250 WORDS)