The chemical composition, fatty acid profile, content of amino acids, minerals, and gross energy of seeds of some commercial linseed oily cultivars: brown-seed (Flanders, Opal and brown-seed mixture) and yellow-seed (Hungarian Gold, Linola™947, Linola™989, Hungarian ecotype) were determined. The nutritive value of seeds for ruminants was also assessed according to the Polish IZ-INRA (1997) standards. Lysine was the main limiting AA for all cultivars. There were significant differences between cultivars in the contents of unsaturated fatty acids, C 182 , C lg . 3 . In the Linola™947 and Linola™989 cultivars, the level of linolenic acid (C, 83 ) was very low (about 2%), but the level of linoleic acid (C 2 ) was over 72% of total acids. There were differences between cultivars in PDIN and PDIE.

The effects of dietary linseed cultivars, traditional (Opal, Omega) or the new Linola cultivar with an increased content of linoleic acid, on the performance and chemical composition of lamb meat and liver were investigated. The animals were fed meadow hay and concentrate. The control group received no linseed in concentrate, whereas the experimental groups received 10% crushed linseed of different cultivars. There was no significant effect of linseed, irrespective of cultivar, on daily weight gains of the lambs, feed conversion, dressing percentage and chemical composition of leg muscle and liver. However, significant (PO.05) changes were shown in the fatty acid profile of meat and liver.

The effects of linseed-based diets for sheep on nutrient digestibility, N retention and some parameters in blood serum and rumen fluid were studied. Linseed-based diets contained more fat (%) and different farty acid profiles. Inclusion of linseed increased crude fat digestibility from 68 to 80% (PO.05), without significant effects on digestibility of other nutrients and N retention. Statistically significant differences (PO.05) were found in the total cholesterol, triacylglyceride and total lipid contents in blood serum, and in the ammonia content of rumen fluid. The 10% addition of linseed to concentrate caused a decrease in VFA (PO.05) in the rumen fluid.

Second-cut lucerne media (Medicago media Pers var. Radius) harvested at the budding stage was ensiled with whole-crop oats (var. Santor), cut at milk stage, at a 75:25 or 50:50 (wt/wt) ratio. Additionally, each combination was conserved with or without an enzyme-bacterial additive (Goldzym). The experimental silages were: lucerne, 75 + whole-crop oats, 25; lucerne, 50 + whole-crop oats, 50; lucerne, 75 + whole-crop oats, 25 + Goldzym; lucerne, 50 + whole-crop oats, 50 + Goldzym. The experiment was conducted on 7-month old male lambs of the Polish Long-haired breed.Neither the content of whole-crop oats in the silage nor the addition of Goldzym had any effect on the chemical composition of silages. However, both factors had a positive effect on fermentation in the silo and silage quality. Voluntary and free-access dry matter intakes were influenced mainly by the lucerne to whole-crop oats ratio. Inclusion of 50% of whole-crop oats increased voluntary dry matter intake as well as digestibility and N-balance.