Influence of Calving Season and Stocking Rate on Beef Cow-Calf Productivity

Abstract

Four cow-calf management systems using Angus and Hereford × Angus multiparous cows were utilized over a 5-yr period to evaluate calving season and stocking rate. The study was conducted on fine sandy loam, Coastal Plains soils in western Louisiana. Outcome groups were: 1) 35 fall-calving (FC) cows, 2) 45 FC cows, 3) 35 spring-calving (SC) cows and 4) 45 SC cows. All units contained 12.0 ha of land subdivided into four paddocks of 4.0, 4.0, 2.8 and 1.2 ha. The 2.8-ha unit was cultivated annually and planted to cool-season annual forage mixtures for use as a creep grazing area by calves. Remaining paddocks were mixtures of common and Coastal bermudagrass sod-seeded annually with ryegrass and white clover. Units were similar concerning seeding, planting and fertilizer levels, but each unit was managed independently. Hay fed and protein supplement consumption was greater (P<.05) for FC than for SC cows and for high stocking rate (HSR) units (45 cow-calf pairs on 12.0 ha) than for low stocking rate (LSR) units (35 cow-calf pairs on 12.0 ha). Cow weights were heavier (P<.01) for LSR compared with HSR systems. Age of cows was greater (P<.05) for FC than SC cows (7.4 vs 6.7 yr). Dam age was not different between LSR and HSR units, whether FC or SC. Calf death losses were greater (P<.05) for SC than FC (5.6 vs 1.2%) units. Weaning weights were higher (P<.05) for fall- born calves than for spring-born calves, and for calves in LSR compared with HSR units. Net monetary returns above costs were greater for FC than SC units. The FC cows on LSR optimized economic returns, while SC cows on LSR had the greatest negative returns.