General introductionThe aim of breeding fodder grasses is to develop high quality cultivars that improve environmentally friendly animal performance and result in a more healthy animal end product. A higher linolenic acid content in the grass increases the content of omega-3- fatty acids and CLA in milk and meat. Higher sugar content in the grass leads to a better use of the protein in the grass and decreased nitrogen leaching. But too much sugar in the grass causes rumen acidosis and may heat the silage when opening. We therefore strive to develop ryegrass cultivars with a high digestibility due to better cell wall digestibility and a moderate sugar content. In other grass species with a lower sugar content such as tall fescue, the sugar content may be increased.
Research approachFirst we develop quick methods to determine the intended quality parameters to study the variation of our gene pool and the heritability of each trait. Next, the desired quality characteristic is fixed in a population for further variety development. The parameters ‘sugar content’, ‘rumen escape protein fraction’ and ‘content of linolenic acid’ were investigated in former projects and need finalization. For the parameter ‘cell wall digestibility’ we develop a NIRS calibration curve. This calibration is used to study the variation in genotypes of perennial ryegrass and tall fescue related to their developmental stage.
Relevance/ValorisationGrassland covers 40% of the acreage in Flanders. Grass is the most important homegrown protein source in cattle farms. The improvement of the energy and protein content of grass leads to better animal performances and cost savings. These improvements also reduce animal emissions (nitrogen, methane). More high quality grass in the ration results in a more balanced milk and meat composition. The knowhow and selected genetic material are used to develop more efficient breeding methods and more quality oriented cultivars. The knowledge may lead to adaptations of criteria for admission of varieties to variety lists.