Effect of flock size and grazing management on sheep production

Abstract

No effect of flock size on wool production was detected over twelve months in flocks of 3, 9, 27, or 135 sheep. Each flock was composed of equal numbers of Merino, Comeback, and Border Leicester X Merino weaners stocked at nine per acre on Phalaris tuberosa-Trifolium subterraneum pastures at Canberra. Liveweight gains and fleece weights of the sheep were similar whether they were set-stocked, rotated around three subdivisions of a rotationally grazed pasture, or in three flocks rotated around three subdivisions of a pasture, which was thus continuously grazed. These results indicate that rotation per se had no important effect on animal production. Merinos in mixed flocks, with Comebacks and Border Leicester X Merinos, gained significantly less weight during autumn and winter and significantly more weight during spring than Merinos in pure flocks at the same stocking rate. There were no differences between pure and mixed flocks in either of the other breeds.