The comparative feeding value of Lindsey 77, alfalfa, and corn silage for finishing beef heifers

Data collected on 120 Angus heifers at the Middle Tennessee Experiment Station, Spring Hill, Tennessee, were used to determine the comparative value of hybrid grass (Lindsey 77), alfalfa and corn silage for finishing beef heifers for slaughter. The heifers were fed a ration of either Lindsey 77, alfalfa or corn silage ad lib, plus limited concentrates for 119 days in Trial I, conducted during the winter of 1966-67, and for 56 days in Trial II conducted during the summer of 1967. The heifers in Trial I were changed to a full feed of concentrates plus a limited amount of the same silage fed during the previous phase for an additional 50 days. In Trial II, the heifers were changed to a full feed of concentrates plus limited corn silage for 47 days following the 56 day period of corn silage full fed. Average daily gains in Trial I were 1.35, 1.60 and 1.73 pounds per head per day during the silage phase and 1.51, 1.50 and 1.58 during the full feed phase for heifers fed Lindsey 77, alfalfa and corn silage, respectively. In Trial II, average daily gains of the heifers fed Lindsey 77, alfalfa and corn silage were 1.53, 2.07 and 1.67 pounds per head per day during the silage phase and 2.25, 2.20 and 2.15 pounds per head per day during the full feed period. Heifers fed corn silage gained significantly faster (P < ,05) than those fed alfalfa or Lindsey 77 silage during the winter trial. However, during the summer trial, heifers fed alfalfa silage gained significantly (P < .05) faster than those fed the other two silages. Feed costs per hundred pounds of gain for heifers fed Lindsey 77, alfalfa and corn silage during Trial I were $27.40, $24.82 and $23.62, respectively, and $21.88, $19.61 and $21.81, respectively, during Trial II. Average return per head above feed and initial cost was highest from heifers fed corn silage in Trial I and highest from heifers fed alfalfa silage in Trial II. These data indicated that these silages, when fed with a limited amount of concentrates followed by a short full feed period, could be used profitably for finishing beef heifers. The season of year (winter or summer) may affect the results obtained from corn silage. This could be a result of severe heating and spoilage of corn silage in the feed bunk, which was observed during the summer feeding trial. The lower rate of gain and higher feed requirement per unit of gain of heifer fed Lindsey 77 silage in both trials indicated that this type of silage was less desirable as a component of a finishing ration for beef heifers than either alfalfa or corn silage.