Developing grassland-based steer production management in an experimental farm to propose alternatives to maize-based bulls systems
Résumé
To improve bovine meat production with dairy breed steers a research on grassland-based steer production was set up. Over 10 years, many production systems were studied for growth performance carcass and a few meat traits. The objectives were to use only pasture and grass silage and hay, and to produce animals weighing 700 kg live weight, with a minimal conformation O (from EUROP scale). In a first series, the aim was to delay the age of castration (from 7 to 16 months) to exploit bull growth performance, and had little effect on carcass weight, tissue composition and conformation. Delaying castration to 16 months of age did modify studied muscle physicochemical characteristics. These trials also confirmed the better meat production portential and better conformation of the Montbliard breed compared to the Holstein breed. In a second series of experiments the aim was assess feeding management, especially grass silage finishing and finishing on pasture. There was also an attempt to spread production to three periods with animals aged 28 to 33 months at slaughter. Preliminary analysis has shown that slaughter weights are hearvier for steers finished on pasture