Introduction to the challenge addressed
In a context of sharply rising material costs raw materials intended for animal feed, the contributions of proteins via concentrates represent an important part and increasing feed costs for finishing cattle. Faced with this context, breeders are looking for solutions for the production of vegetable proteins within the operation itself in order to reduce the cost of external purchases.
Description of the innovation
A test has been carried out with the purpose to assess the benefit of adding grass silage as a supplement protein content of a ration based on maize silage for the finishing of beef heifers. Grass silage in the right stage and in good conditions makes it possible to completely replace the soybean meal in a silage-based ration for finishing meat heifers with a high ingestion capacity such as Charolais.
The "control" group received a ration based on maize silage rationed (8.5 kg of DM/heifer/day) supplemented with 1.2 kg of soybean meal and 120g of mineral. The "experimental" batch was supplied with a mixed ration distributed ad libitum. This ration is composed of 2/3 of grass silage and 1/3 of silage of maize (in dry matter) and 50 g of mineral. These rations are established for a daily growth objective of 1,000 g. Despite a higher level of consumption, average daily growthof the “experimental” batch are identical to those of the “control” batch. Also, the consumption index of the “experimental” batch is heavily degraded. The heifers of the 2 batches produced identical carcasses (weight, conformation and state of fattening).
The use of grass silage in addition to the ration at maize silage base is only possible on the condition to dispose of land areas (catchment, hay meadow, etc.) to produce the quantities of additional fodder necessary for finishing heifers. Then the grass silage must be harvested at the right stage and under the right conditions.
Impact on farm performance
An important economic impact is that production of extra plant proteins makes it possible to reduce the cost of external purchases which is exactly the challenge beef farmers actually are facing.
Further information
http://www.journees3r.fr/spip.php?article4289
Authors: Mylène Berruyer and Hèlène Fuchey – Institut d’Elévage