Jon Schoonmaker and Vern Anderson
Little animal performance information is available on immature or low test weight, high-moisture corn. Mature high-moisture corn is generally perceived to have more energy than dry-rolled corn as it is digested more thoroughly in the ruminant animal. As the corn kernel dries down, the starch becomes more compact. This compaction and other physiological developments make the kernel less digestible (Pritchard, 2005). Dry rolling or grinding increases digestibility of dry corn, but optimum digestibility is not achieved. High-moisture corn ferments more rapidly in the rumen compared to dry-rolled corn, and most of the starch is removed in the rumen. Immature corn, however, with a higher proportion of fiber from the bran and germ, should not produce the same acidosis potential as mature corn. This study was conducted to compare dry-rolled mature corn with immature high-moisture corn from the harvest of 2004 in finishing feedlot diets.
Ninety-eight crossbred steers (765.4 ± 22.4 lbs.) were
allotted by source and weight to a dry-rolled or high-moisture corn-based diet
(6 pens per treatment, 8 to 9 head per pen) to determine the effect of corn
type on performance and carcass quality. Diets were formulated to contain 12.3%
CP and 64.7 MCal NEg/cwt.
Bushel test weight varied with the many different loads of immature corn
delivered to the feeder. The range was
estimated at 37 to 48 pounds per bushel with an average of 42 to 44
pounds. Moisture content of the corn was
taken as it was removed from the feedyard pile (two loads per week). The wet corn averaged 72% dry matter over
the trial. Dry, mature corn averaged 54
pounds per bushel and was 14% moisture. Ten out of 12 of the pens were
slaughtered at Tyson Foods (
Cattle fed mature dry-rolled or immature high-moisture corn gained similarly (3.79 vs. 3.91 lbs. /d, respectively; P > 0.44), and consumed a similar amount of dry matter (22.4 vs. 21.8 lbs. /d, respectively; P > 0.24) over the entire trial. Some period to period variation was observed but overall, cattle fed the immature wet corn exceeded the performance expectations. No differences were observed for hot carcass weight, dressing percent, ribeye area, fat thickness, yield grade, marbling score, or percentage of carcasses grading choice (P > 0.24). Percent kidney, pelvic, and heart fat was greater for cattle fed dry-rolled corn (2.43 vs. 2.23%, P < 0.04).
Considering the similarity in animal performance in this
study, feeders may have an economic advantage if they can purchase immature
corn grain at a discount from corn farmers with no cattle. At a minimum, feeders can save corn growers
the drying costs and negotiate an advantage in price. Corn growers, on the other hand, may want to
consider feeding cattle to capture more value from their grain production. The
net result could be more pounds of beef per acre and increased profits to the
feeding enterprise. The positive outcome
of this study is another reason to consider the opportunities for cattle and