Silage of young harvested alfalfa (Medicago sativa) as home-grown protein feed in the organic feeding of laying hens

The aim of the study was to assess the suitability of very young harvested alfalfa as a protein source for laying hens. Alfalfa was harvested at a very early stage of maturity, chopped and conserved as silage. A subset of the crop was additionally treated with a twin-screw extruder prior to ensiling. For the feeding trial, four groups were investigated. The control group (A) was fed with a complete feed mixture, groups B and C were offered the chopped and extruded silage, as well as a supplemental feed mixture and group D received pellets which consisted of the extruded silage and the supplemental feed mixture. The silage was calculated to form 20 % (in relation to the dry matter) of the daily diet of the animals. For this purpose, the offered supplemental feed mixture was matched with regard to the nutrient content to the desired silage intake. The feed was offered ad libitum. The silage consumption represented 10 to 20 % of the dry matter intake and is apparently influenced by the offer of the outdoor access. Laying performance, egg weight and body weights of the animals in the experimental groups reached the level of the control group. It was concluded that the use of significant amounts of very young harvested alfalfa which was ensiled is possible without losses of performance in the organic feeding of laying hens. The additional extrusion treatment of the wilted crop had no benefit, either for the ensiling or for the animals’ productivity.