Trials of multi paddock grazing systems on veld part 3 a comparison of 6 grazing procedures at 2 stocking rates
Denny, R.P.; Barnes, D.L.
Rhodesian Journal of Agricultural Research 15(2): 129-142
1977
Accession: 006840631
In a veld grazing trial on sandy granite-derived soils a comparison was made between 6 grazing procedures, involving 3 periods of stay, 5, 10 or 20 days, in either 4-or8-paddocks units. Each procedure was applied at 2 stocking rates, the 1 rate being double the other. The grazing procedure treatments began about 6 wk after the start of the growing season and were continued until the start of the next growing season. Fresh sets of yearling steers were used each year. A protein-rich supplement was fed at the same rate to all groups of steers during the dormant season. The trial lasted 5 yr. Body-mass gains per steer differed markedly between grazing procedure treatments during the mid and late growing season, but were similar with all grazing procedures during the dormant season. In each year a highly significant negative linear relation was found between grazing intensity and gain per steer during the mid and late growing season. Irrespective of the grazing procedure and stocking rate applied, gain per steer was high only where the grazing intensity was low, in the order of 5-10 livestock unit days per ha in each paddock during each grazing cycle. During the dormant season gains per steer were higher at the low than at the high stocking rate. Body-mass changes in the dormant season were much smaller than in the growing season and with the more productive grazing procedures over-all gains per hectare were much higher at the high stocking rate than at the low rate. The treatments had no differential effects on botanical composition and basal cover of the veld.