Effects of grazing strategy and stocking rates on wool quality and yield in the Andean Altiplano of Peru

Abstract

Annual wool production of 120 native Corriedale ewes (age, 2.5–3.0 years; mean weight, 30 kg) was monitored from 1981 to 1983 in two experiments: (1) a rotational grazing system at three stocking rates (two, four and six ewes per hectare), and (2) continuous, rotational and common use rotational (with cattle) management systems at a stocking rate of three ewes per hectare. Greasy fleece weights, staple lengths and fiber diameters were recorded after shearing in 1982 and 1983. Stocking rates had no significant effect on greasy fleece weights per ewe. Greasy fleece weights per hectare increased proportionally with stocking rate. Fiber diameter decreased significantly ( P<0.05) as stocking rate increased. Grazing strategy did not significantly affect staple length or fiber diameter between continuous and rotational grazing with sheep only, but greasy fleece weight was 9% greater ( P<0.01) under continous grazing. The common use rotational grazing system produced the lowest wool production with a significantly smaller ( P<0.05) fiber diameter than the continuous and rotational grazing strategies with sheeo only. Care should be taken to prevent overstocking with cattle under common use grazing if wool production is to be maintained. A reduction ( P<0.05) in greasy fleece weight was noted in lactating ewes compared to non-lactating ewes. The results indicate that ewes producing lambs are more sensitive to different grazing strategies than are open and dry ewes. Wool production did not appear to be a sensitive indicator of grazing treatment differences.