Le. Phillip et al., Optimizing pasture management for cow-calf production: the roles of rotational frequency and stocking rate in the context of system efficiency, CAN J ANIM, 81(1), 2001, pp. 47-56
An experiment was conducted on grass pasture in southwestern Quebec to eval
uate the benefits of management intensive grazing (MiG). Sixty-one spring-c
alving cows, with calves, were assigned to nine treatments, arranged as a 3
x 3 factorial of rotational frequency (RF) thigh, 2-d; medium, 6-d; contin
uous grazing) and stocking rate (SR) ( high, medium and low; 0.5, 0.7 and 0
.9 ha per cow-calf pair, respectively). Hay harvested early in the season w
as used for pasture supplementation late in the season. Increasing RF had n
o effect (P > 0.05) on mean forage mass. Increasing SR from 0.9 to 0.5 ha p
er cow-calf pair resulted in a linear reduction (P < 0.01) in mean forage c
rude protein (CP) in September; forage CP was highest with 6-d rotation. At
the start of the season, increasing RF caused a linear decrease (P < 0.01)
in cow gain per head as well as gain per hectare, whereas increasing the S
R caused a linear increase (P < 0.01) in cow gain per hectare without influ
encing cow gain per head (P > 0.05). Calf gain per hectare increased linear
ly (P < 0.01) in response to SR throughout the grazing season, but calf gai
n per head was unaffected (P <greater than> 0.05) by SR. Calf gains per hea
d and per hectare were not influenced by RF until late season, when calves
under a 6-d RF performed slightly better than both continuously grazed and
2-d RF calves. A 6-d-high SR system generated the greatest net revenue. The
study showed little benefit of MIG on animal performance, but substantial
benefit on efficiency of land use and economic performance.