OBJECTIVES Short term:
To study the effects of a reduction of stocking rate of unfertilised mountain pastures on the growth of the animals
Long term:
To study the effects of desintensification of mountain pastures on the evolution of the vegetation
RESULTS
CONCLUSIONS
Up to now the reduction of the stocking rate had a very little effect on the botanical composition of the sward.
A reduction of the stocking rate had beneficial effects on the individual performance of the steers and on the duration of the grazing period.
The stocking rate had a marked effect on the amount and on the spatial variability of residual herbage at the end of the grazing periode.
The extensive use of mountain pastures in Switzerland to fatten crossbred steers can be an interesting alternative to giving up these areas.
Effects of the stocking rate on steer performance and vegetation patterns on mountain pastures
J. Troxler
1and A. Chassot
21Swiss federal research station for plant production (RAC), 1260 Nyon, Switzerland
2Swiss federal research station for animal production and dairy products (ALP), 1725 Posieux, Switzerland
The problem:
Less animals on mountain pastures Îabandon of marginal areas
Territory management Environment
A solution:
Extensive beef production with grazing period on unfertilised mountain
pastures at low stocking rate
Environmentally safe production Quality products Open landscapes
and high biodiversity
Consumers
Politics
Experimental treatments:
3 stocking rates (applied from 2000):
-1.8 600-kg animal unit (AU) ha-1(control) -1.2 AU ha-1
-0.6 AU ha-1
Identical number of animals on the three stocking rates (2001:19, 2002:21), constant during the whole grazing season
Rotational grazing on 3 paddocks, 4-5 rotations
Dates of start and end of the grazing period depending on grass availability
. Evolution of the botanical composition 2000 – 2002 (Daget and Poissonet)
. Mesure of the residual herbage at the end of the grazing periode
Site (Les Verrières, Swiss Jura), 1126 m a.s.l.:
Dominant vegetation:Festuca rubraL. / Agrostis tenuisL.
Fertilisation: none since 1986
MATERIAL AND METHODS
Rearing period
Grazing period I
Winter
0 100 200 300 400 500 600
0 5 10 15 20 Age (months)
LW (kg)
0 250 500 750 1000 1250 1500
ADG (g/d)
Finishing period Grazing period II (mountain)
Mixture low quality hay /
grass silage Full milk
HayConcentrate
Animals:
Crossbred steers, Limousine X Red Pied
3 series (2001-03) Production system
5.09 8.08 11.07 13.06
15.10
24.09
05.09
11.05 16.05 22.05 0 20 40 60 80 100 120 140 160 180
Cumulative LWG (kg animal-1)
11.06 17.07 13.08 16.09
18.09 17.10
26.08
15.0508.05 21.05
2001 2002
1.8 AU ha-1 1.2 AU ha-1 0.6 AU ha-1
5.09 8.08 11.07 13.06
15.10
24.09
05.09
11.05 16.05 22.05 0 20 40 60 80 100 120 140 160 180
Cumulative LWG (kg animal-1)
11.06 17.07 13.08 16.09
18.09 17.10
26.08
15.0508.05 21.05
2001 2002
1.8 AU ha-1 1.2 AU ha-1 0.6 AU ha-1
5.09 8.08 11.07 13.06
15.10
24.09
05.09
11.05 16.05 22.05 0 20 40 60 80 100 120 140 160 180
Cumulative LWG (kg animal-1)
11.06 17.07 13.08 16.09
18.09 17.10
26.08
15.0508.05 21.05
2001 2002
5.09 8.08 11.07 13.06
15.10
24.09
05.09
11.05 16.05 22.05 0 20 40 60 80 100 120 140 160 180
Cumulative LWG (kg animal-1)
11.06 17.07 13.08 16.09
18.09 17.10
26.08
15.0508.05 21.0515.0508.05 21.05
2001 2002
1.8 AU ha-1 1.2 AU ha-1 0.6 AU ha-1 1.8 AU ha-1 1.2 AU ha-1 0.6 AU ha-1
Cumulative mean liveweight gain (LWG) per animal at three stocking rates during the grazing period in Les Verrières
y Through reduction of the stocking rate of unfertilised mountain pastures the growth rate of the animals could be maintained at a relatively high level up to the end of the grazing season.
y Furthermore, the lenght of grazing season could be extended by 43% in 2001 and 69% in 2002.
1 Including Cyperaceae and Juncaceae Evolution of the botanical composition
1 Including grass growth after the animals have been removed
SR 2002 2003
1.8 9
16
11.2 8 5
0.6 12 13
Stoking rate (SR) (600-kg AU ha-1)
1.8 1.2 0.6
Plant groups or Plant families
2000 2002 2000 2002 2000 2002
Grasses 74% 62% 73% 64% 72% 71%
Legumes 5% 12% 6% 10% 7% 6%
Herbs and weeds1 21% 26% 21% 26% 21% 22%
Amount of residual herbage (dt DM ha-1) at the end of the grazing season
