Linseed and sunflower seed in dairy cow feeding

Three groups of 11 dairy cows each received the same ration composed of hay ad libitum, fodder beet and concentrate. During the experimental period 500 g fat contained in either sunflower seed, untreated and extruded linseed were distributed. Forage- and total intake were not influenced by the different oilseeds. No significant differences were detected by the milk yield and -contents. With the distribution of sunflower seed, linseed untreated and extruded the milk fat composition was improved in technological (C18:1 vs. C16:0 > 0.8) and nutritional terms: Decline of short- respectively mid-chain and saturated fatty acids; increase of long chain and polyunsaturated fatty acids e.g. linoleic and linolenic acid. Extruded compared with untreated linseed higher contents of linoleic and linolenic acids (+11 % respectively +52 %) were observed. Even if the content of linolenic acid in the milk with extruded linseed more than doubled, the calculated passage rate from feed in the milk was only 6.8 %. The search for a still better protection against microbial hydrogenation in the rumen could make sense. In the fresh cheese compared to the milk the proportion of valuable fatty acids as CLA, Omega-3 and -6 as well as unsaturated fatty acids were slightly lower. The cheese maturation as well as the processing to butter hardly affected the fatty acid profile. Milk from the extruded linseeds generated the best dough of the model-cheeses (Tilsiter and Emmentaler).