The effect of herbage availability on animal performance off Kikuyu and Coastcross II.

Under continuous grazing animal performance on Coastcross II was superior to that on Kikuyu at all levels of pasture availability. Superiority however depended on availability under rotational grazing. On Coastcross animal performance was better under continuous grazing than under rotational grazing at all levels of pasture availability but for Kikuyu superiority again depended on the level of availability. Large seasonal changes in animal performance occurred for both species in a season in which good early rains were followed by a relatively dry autumn but little change occurred in a season of generally low rainfall.Keywords: animal performance; coastcross ii; continuous grazing; grazing; herbage availability; kikuyu; natal; pennisetum clandestinum; rotational grazing; seasonal changes; south africa; ukulinga research statio

Nitrogen fertilization, stocking rate and rotational grazing effects on steers grazing Pennisetum clandestinum.

Kikuyu pastures at the Ukulinga research farm near Pietermaritzburg were fertilized with 150 and 300 kg nitrogen (N) ha -1 in the summer periods of 1985-86 and 1986-87, and were continuously grazed with steers at stocking rates of 5.4, 8.0 and 10.7 steers ha -1. In the second season the high N level pasture was also grazed under 12-paddock rotational grazing at stocking rates of 5.4, 8.0 and 13.4 steers ha -1. In the first season the high N level provided higher (P < 0.05) animal weight gains, but there was no difference between N levels in animal weight gain during the second season. Rotational grazing provided higher weight gains than continuous grazing in the second season. The increased weight gains obtained from high N fertilization and rotational grazing were probably caused by higher forage availability rather than higher forage quality.Keywords: average daily gain; continuous grazing; fertilization; forage quality; grazing; grazing effects; herbage availability; kikuyu; kikuyu pastures; nitrogen fertilization; pasture; pastures; pennisetum clandestinum; pietermaritzburg; rotational grazing; south africa; stocking rate; ukulinga research statio

A study of short term grazing patterns on Coastcross 2 under different grazing regimes.

In this study the disc meter was successfully used to measure pasture yield in situ and thus provide an objective basis to adjust animal numbers on treatments with variable stocking rates. Realistic estimates of pasture dry matter consumption and production were made on rotational grazing systems and animal selection patterns were described in terms of pasture availability. The critical level of pasture availability below which animals were on restricted intake was estimated to occur as a mean disc meter reading of approximately 11 cm. This conclusion was supported by the time animals spent grazing on each treatment and the response of average daily gain to various levels of pasture utilization.Keywords: average daily gain; consumption; daily gain; disc meter; dry matter; grazing; grazing pattern; grazing systems; intake; pasture; production; rotational grazing; south africa; stocking rate; stocking rates; treatments; utilization; yiel

Herbage height as a determinant of the preference of steers grazing three pasture species.

Steers grazed Rhodesgrass, kikuyu and Coastcross II pastures in high utilization (HUG) and high production (HPG) rotational grazing systems. Grass tillers were marked and monitored to establish height preferences shown by animals. Generally, longer herbage was selected on all three grasses compared to herbage that was rejected. Herbage height and amount grazed was linearly correlated (r = 0,43 to 0,87) but these relationships differed for different situations. In Rhodesgrass 60% of the tillers were uprooted by the end of the grazing period while in kikuyu 32% and Coastcross II 17% were uprooted. In all three grasses tillers that were uprooted were shorter than those which remained rooted after grazing.Keywords: chloris gayana; coastcross ii; grasses; grazing; grazing systems; herbage; kikuyu; natal; pastures; pennisetum clandestinum; preference; production; rotational grazing; south africa; ukulinga research station; utilizatio

Productivity of one- and two-year-old steers grazing Coastcross 2 (Cynodon hybrid) at four stocking rates.

Coastcross II pastures were continuously grazed with 1- or 2-year-old steers at stocking rates between 5.4 and 13.4 animals ha -1 in 1985-86 and 1986-87 at the Ukulinga research farm near Pietermaritzburg. In the first season there was no difference between animals of different ages in the ADG-stocking rate and herbage availability-stocking rate regressions. In the second season ADG for 2-year-old steers was higher (P < 0.05) and herbage availability lower (P < 0.05) than for 1-year-olds. Maximum gain ha -1 for 2-year-old steers in the second season (1 178 kg) was 38% higher than for 1-year-olds (853 kg).Keywords: adg; average daily gain; bermudagrass; coastcross ii; cynodon; grazing; herbage; herbage availability; natal; pastures; pietermaritzburg; productivity; south africa; stocking rate; stocking rate

A proposed method for determining long term optimum utilization intensities of pastures and veld.

Application of utilization intensity as an experimental variable by the use of the pasture disc meter and the put- and take technique is recommended as an alternative to stocking rate experiments. Utilization intensity allows stocking rate to be used as a measure of pasture productivity and consequently the relationship between animal gain and stocking rate and the relationship between veld condition score and utilization intensity could be used to determine a long term optimum utilization intensity for veld in good condition and a range of acceptable utilization intensities which will allow veld in poor condition to recover.Keywords: condition; disc meter; method; optimum utilization; pasture; pasture disc meter; productivity; range; stocking rate; technique; utilization; veld; veld condition; veld condition scor