Factors affecting in sacco degradation of dry matter and crude protein in grass silage

Authors

• Jouko Setälä Valio Finnish Co-operative Dairies’ Association, Research and Development Department, Kalevankatu 56, P.O. Box 176, SF-00181 Helsinki, Finland 
• Alem Tesfa University of Helsinki, Department of Animal Husbandry, SF-00710 Helsinki, Finland
• Aino Rauramaa Valio Finnish Co-operative Dairies’ Association, Research and Development Department, Kalevankatu 56, P.O. Box 176, SF-00181 Helsinki, Finland

DOI: https://doi.org/10.23986/afsci.72195

Abstract

The degradability of dry matter and crude protein was studied in 96 grass silages, which were collected from practical farms in different parts of Finland. The degradabilities were determined by the nylonbag technique in sheep on a grass silage and hay (50 : 50 on DM basis) -based diet. Among chemical components the N-free extracts increased, and the crude fibre decreased the dry matter degradation in the rumen. The correlation between the end-products from silage fermentation and the dry matter degradability was generally negative. The level of the crude protein degradability was significantly increased when the crude protein content in the silage DM was increased. The amount of NO3 in the silage DM had a similar effect. The rate of crude protein degradation was regulated mainly by the proteolysis in the silage, e.g. the amounts of NH, and especially watersoluble N in the total N of silage. Crude fibre tended to protect crude protein against ruminal digestion.