Utilization by Cattle, Sheep, and Goats of Forage Harvested from Long-Term Bermudagrass Spray Fields Receiving Swine Lagoon Effluent1

Bermudagrasses frequently serve as receivers of swine lagoon effluent in swine production confinement systems in the Southeast. This study evaluated DMI and digestion of field-chopped, dehydrated regrowth forage cut from mature Coastal bermudagrass spray fields following harvest in late July. Four treatments were evaluated in separate experiments each with cattle, sheep, and goats. The treatments consisted of forage harvested at 2 wk of regrowth and either fed chopped (2-WC) or pelleted (2-WP) and that harvested and pelleted at 3 wk (3-WP) and 4 wk (4-WP) of regrowth. The long-time established spray fields varied in the proportions of bermudagrass but averaged 45% for the 2-wk regrowth and 50% for the 4-wk regrowth; the balance was composed of annual grasses and broadleaved weeds. All three pelleted forages were readily consumed with DMI (kg/100 kg of BW) averaging 2.99 for steers, 4.35 for sheep, and 3.21 for goats. Steers and goats consumed all pelleted treatments similarly, whereas sheep consumed 2-WP and 3-WP similarly (4.41) but consumed less 4-WP (4.23) compared with 2-WP (4.49). Pelleting increased (P≤0.01) DMI compared with chopping (3.01 vs 2.16 ± 0.087 for steers, 3.29 vs 2.37 ± 0.071 for goats, and 4.49 vs 2.54 ± 0.072 for sheep). Steers and sheep digested 2-WP and 4-WP similarly and digested both at rates greater (P≤0.05) than 3-WP; goats digested all similarly (P=0.11). These short-term responses indicate that forages from mature bermudagrass fields sprayed with swine effluent have potential as a feed in ruminant production systems.