The 2008 Joint Meeting of the Society for Range Management and the America Forage and Grassland Council. |
Thursday, January 31, 2008 - 8:40 AM
Grazing Patterns of Yearling Heifers in Juniper Woodlands when Supplemented Away from Water
Derek W. Bailey, Barbara K. Witmore, and Andres F. Cibils. Department of Animal and Range Sciences, New Mexico State University, PO Box 30003, MSC 3-I, Las Cruces, NM 88003
A study was conducted in central New Mexico to examine the grazing patterns of yearling heifers supplemented with range cake or low-moisture blocks (LMB) in juniper (Juniperus monosperma) woodlands. Heifers (n=38) were randomly divided into 4 groups and evaluated in 4 pastures (259 ha) in a replicated crossover design during autumn. Two groups had access to LMB approximately 1.6 km from water, while other groups were fed 6.35 kg · heifer-1 · week-1 of range cake in similar locations. Intake of LMB was low (59 g · d-1). Average daily gain during the 53-day study was similar (P=0.51) for heifers fed LMB (1.05 ± 0.09 kg · day-1) and range cake (0.93 ± 0.09 kg · day-1). Average distance to water was similar (P = 0.31) for heifers fed LMB (943 ± 63 m) and range cake (902 ± 63 m). Heifers spent similar (P=0.73) amounts of time within 100 m of placement sites of LMB (1.6 ± 0.7 hours · day-1) and range cake (1.2 ± 0.7 hours · day-1). Overall, heifers spent 6.1 ± 0.2 hours · day-1 within 30 m of perimeter fences. To examine daily movement patterns, pastures were divided into 4 equally-sized sections. Heifers did not remain in the same section of a pasture on consecutive mornings more than expected by chance. Heifers in both treatments did not visit water on 23.0 ± 2.7% of study days (P=0.31). Unlike what has been observed with cows, strategic supplement placement had little effect on yearling heifer grazing patterns in this study. Heifers were not attracted to supplement placement sites near moderate to dense stands of juniper. Additional research is needed to better understand yearling cattle grazing patterns and to develop techniques to manipulate distribution of yearlings with strategic supplement placement.