Finishing of steers following a summering period on mountain pastures: effect of the finishing duration on fatening performance

Subsequent to a summering period of 48 crossbred steers (Limousin x Swiss Fleckvieh) on low input mountain pastures, the effect of a finishing period on fattening performance was investigated. Steers were slaughtered either on the day of returning from the mountain pastures (no finishing) or after 4, 8 and 12 weeks of indoor finishing (loose housing on deep litter). The basic ration consisting of a mixture of grass – and maize silage (1:1 on a DM basis) was fed ad libitum. The supplemental concentrate was limited to 2 kg of DM per animal and day. Steers weighed over 500 kg at the beginning of the finishing period. During the finishing period, the steers realized a mean daily growth rate (DGR) of 1.7 kg which more than doubled DGR measured during summering independently of live weight and finishing duration. The phenomenon of compensatory growth is most likely the cause of these exceptional growth performance which is supported by the observed increased feed intake (+ 17 %) along with reduced energy requirements. Without finishing, the steers generally did not reach a satisfactory fatness score. A finishing period of 4 weeks was long enough to alleviate this deficit and to improve carcass conformation, killing-out percentage and carcass weight. To further extent the finishing period only has advantages for lighter animals. Current feeding recommendations do not sufficiently take into account compensatory growth.