A Comparison of Continuous and Rotational Grazing

Abstract

Continuous and rotational grazing of a brome-alfalfa-creeping red fescue pasture was compared at the University of Alberta Ranch in 1975, 1976, 1977, and 1978. Productivity, in terms of animal weight gain and dry-matter consumption, was studied together with changes in the sward composition. In 1977 and 1978 the weight gains from the rotationally grazed areas were nearly double those obtained from continuous grazing (218 vs 119 kg/ha). The percentage by weight of alfalfa in the sward increased under rotational grazing from 23 to 47?$. The herbage in the rotationally grazed field was more digestible and contained more calcium, magnesium, copper, and crude protein than did that in the continuously grazed area. Animals in the continuously grazed fields spent 2.4 hours longer per day grazing than did the animals which were rotationally grazed. Grazing systems must be adapted to local conditions, and comparisons of trials carried out by different workers in different areas should be made only with caution. Heath, et al. (1973) indicated that in the North American continent rotational grazing favoured legume persistence and improved yields. They regarded rotational grazing as being essential to achieve maximum production per hectare and for the efficient use of management inputs. These conclusions agree with results obtained in Europe (Peter 1929), but are not in agreement with conclusions drawn from trials carried out in the northwestern United States and in western Canada. Hodgson et al. (1934) found that rotational grazing did not improve pasture quality, and they doubted if rotational grazing was economical in western Washington. Rogler (195 l), working in North Dakota, showed that steers on moderately but continuously grazed pasture gained more per head than animals which were maintained under a rotational grazing management system. Campbell (1961) at Swift Current, Saskatchewan, concluded that continuous grazing was to be preferred over more intensive management systems. Hybbard (1961) also stated that for conditions at Manyberries, Alberta, "conservative continuous grazing was the most practical method of pasture use." Cooke et al. (1965) presented data from Melfort, Saskatchewan, which indicated that over a 7-year period rotational grazing did not increase beef production over that obtained where continuous grazing was practiced. In spite of these conclusions in the literature, the extension services of Alberta Agriculture have recommended rotational grazing; and farmers, in some parts of western Canada, have used that system. It is evident that either conditions in western Canada and northwestern United States differed from those in the rest of the North American continent and in Europe in some way that favours continuous rather than rotational grazing, or that the rotational grazing system practiced by research workers had not been satisfactorily adapted to local conditions. The object of the study reported here was to compare continuous and rotational grazing in central Alberta in terms of pasture compositio...

The Economics of Desertification, Land Degradation, and Drought Toward an Integrated Global Assessment

“…A study in the United States found that rotational grazing, as compared with continuous grazing, increased beef gain per unit area by 35-61 percent and the profit from milk by 61 percent (Henning et al 2000). Walton, Martinez, and Bailey (1981) also found a 63.5 percent weight gain of cows due to rotational grazing. To obtain a conservative estimate, we assumed that overgrazing reduces carcass live weight and milk production by 32 percent.…”

Development and evaluation of grazing-tolerant alfalfa cultivars: A review

“…Rotational stocking is generally accepted as essential to maintain alfalfa stands and to allow vigorous regrowth and subsequent animal productivity (Leach 1979;Walton et al 1981). The more intensive management required for rotational stocking systems is acceptable to dairy producers.…”

Effect of grazing system, stocking rate and season of use on diet quality and herbage availability of alfalfa-grass pastures

“…The effects of grazing system, forage maturity associated with advancing season, and forage species on the nutrition of grazing cattle have been evaluated (Walton et al 1981;Howarth and Goplen 1983;Sharrow 1983;Jung et al 1985;Sanderson and Wedin 1989;Beauchemin 1991;Beauchemin and Iwaasa 1993), but never in a single study. For example, Beauchemin (1991) reported decreases in CP (19.4 to 16.7%) and increases in NDF (38.8 to 47.6%) as alfalfa was harvested in early versus midbloom stages.…”