Pearl Millet Silage for Growing Beef Heifers and Steers

Abstract

Spring and late summer planted crops of HGM-100' pearl millet grain hybrid [Pennisetum glaucum (L.) R. Br.] were compared with corn (Zea mays L.) as potential silage for growing beef cattle (Bos taurus). In Experiment 1 separate plantings of pearl millet were harvested at the soft dough stage of grain maturity in either July or September 1993. Wilting the spring-planted first crop millet (FCM) prior to harvest or direct cutting and adding a microbial preservative to the summer planted second crop millet (SCM), did not improve fermentation. The pH was higher, and lactic acid much lower for millet silages compared with corn silage (HCS; pH and lactic acid [% of dry matter (DM)], respectively, were: FCM, 5.74, 3.22; SCM, 4.12, 3.34; HCS, 3.66, 8.69). Dry matter intake by growing heifers (average initial weight 600 lb) was 6.5 lb/d for both FCM and SCM silages, and higher (P < 0.01) at 13.4 lb/d for HCS. Average daily gains (ADG) were 0.34 and 0.45 lb/d, respectively, for FCM and SCM silages, and ADG was higher (P < 0.01) at 2.1 lb/d for HCS. In Experiment 2 (1996), silage treatments included corn silage (SCS), direct-cut HGM-100 millet treated with an inoculant (MS) or inoculant plus 0.5% ground corn (MSC) added to improve fermentation of silages. These millet silages had higher DM (31% and 36%), somewhat lower crude protein (11% to 11.5%), but they had improved fermentation compared with millet silages in Experiment 1. In Experiment 2, 75 beef steers (avg initial wt 600 lb) were assigned to the three silage treatments and fed in drylot for 56 d. Steers fed SCS had higher ADG (P < 0.05) and improved DM/gain (P < 0.05) than steers fed millet (MS) or corn (MSC). Respective 56-d ADG (pounds) and DM/gain for treatments were: MS, 1.71, 7.35; MSC, 1.70, 7.92; SCS, 2.69, 5.05. Steer performance indicated that millet silages might be efficiently used in growing cattle diets, but supplemental energy would be required for increased performance in comparable corn silage diets.