Comparison of ryegrass—white clover pastures with and without paspalum and kikuyu grass

Abstract

Abstract Three pasture types were compared under 2 sheep management systems over 3 years. A basic temperate species mixture of ryegrass (Lolium × hybridum Hausskn. ‘Grasslands Ariki’) and white clover ( Trifolium repens L. ‘Grasslands Huia’) (pasture R) was compared with the same mixture plus either paspalum (Paspalum dilatatum Poir.) or kikuyu grass (Pennisetum clandestinum Hochst.) (pastures P and K respectively). Subtreatments consisted of a ewe/lamb system stocked at 19.8 ewes/ha, and a put-and-take hogget system in which numbers were adjusted to match feed supply on a 20-day cycle. There were no significant differences in sheep production between R and P pastures in the ewe system (ewe and lamb live weights, greasy fleece weights) but there was a 7% advantage to P under the hogget system (intake of metabolisable energy/ha). Under the stocking rates used, paspalum content fell to low levels. Live weights of ewes on K pastures fell further in spring than those on other pastures but they recovered faster after lactation. Greasy fleece weights were also lower at spring shearing and on an annual basis but there were no differences at autumn shearing. Lamb production (live weight/ha) did not differ significantly among pastures during the 21 weeks lambs remained on the trial. Under the hogget system, estimated annual metabolisable energy intake of K pasture was 10% less than that on R with K yield being lower in spring and higher in autumn.