Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 7/24/2001
Publication Date: N/A
Citation: N/A Interpretive Summary:
Technical Abstract: We have been investigating the impact of using cattle in forage systems to restore degraded cropland in the Southeastern US. The object of this study was to evaluate performance of steers grazing bermudagrass pastures that were fertilized by three fertilizer treatments and were stocked at two herbage masses. Yearling Angus steers were randomly assigned to 18 paddocks (.65 to .75 ha) which were organized in three blocks. Three nitrogen (N) treatments included N provided as ammonium nitrate (M), poultry litter (L) or by crimson clover plus ammonium nitrate (C). Ammonium nitrate and L were applied twice each year to annually provide 200 kg N/ha. Cattle grazed for 140 days from mid-May until mid-October for five years. The high stocking treatment (HS) was stocked maintain 1,500 kg forage/ha and low stocking rate (LS) maintained 3,000 kg/ha with a differential of 1,500 kg/ha between both rates. Stocking rates were adjusted every 28 days by put-and-take. After five years, the M treatment had greater average total grazing days/season (1,092) than C (926) and L (944), (P< .05). The L treatment had less total animal gain/ha, 607 kg/ha than did M (733 kg/ha) and C (688 kg/ha) treatments (P< .05). Average daily gain (ADG) was greater for C (.78 kg/d) than L (.69 kg/d) (P< .05) with M intermediate (.74 kg/d). Steers grazing HS had 1,118 grazing days vs. 857 LS (P< .05). Steers grazing HS had greater total animal gain/ha, 732 than LS with 620 kg/ha (P< .05). Steers grazing LS had greater ADG .82 kg/d than HS .65 kg/d (P< .05). Poultry litter supported acceptable steer production though animal production was less than M and C. Soil organic carbon was positively correlated with grazing days r=.49 (P=.04). Results imply that cattle can be employed to restore eroded cropland.