The chemical composition and nutritional value of pumpkin (Cucurbita pepo) seed cake (PSC) were studied and compared with those of casein and soybean meal. Crude protein and ether extract content in dry matter of PSC was 598.0 g/kg and 124.6 g/kg, respectively, and was higher than the percentage of these components (474.2 and 28.3 g/kg, respectively) in soybean meal used in this experiment. The main fatty acids in PSC cake were oleic acid (50.4%) and linoleic acid (29.9%). Protein found in PSC contained considerable quantities of tryptophan (1.54 g/16 g N); by contrast, the content of lysine (3.21 g/16 g N) and isoleucine (3.83 g/16 g N) was low. Small quantities of phenolic compounds (2.61 g/kg), low activity of trypsin inhibitors (1.33 TUI/mg) and small quantities of alpha-galactosides (19.9 g/kg) were found in PSC. Among antinutritive components only the content of inositol phosphates in PSC (40.5 mg/g) was higher than in soybean meal (10.8 mg/g). True digestibility coefficient (TD) of PSC protein was similar (83.1%), but protein efficiency ratio (PER) was lower (1.01) in comparison with soybean meal (83.5% and 1.50, respectively). After supplementation with lysine, TD (85.9%) and PER (1.43) in PSC were comparable with TD and PER to soybean meal. The PSC-soybean meal mix diet (protein ratio 1:1) had a higher PER value than the diet with soybean meal only (1.98 vs. 1.50).

An experiment was performed on 37 Holstein-Friesian cows during the first 120 days of lactation. The cows were fed balanced diets composed of haylage and maize silage (together 52% dry mater) and a concentrate containing 19% crude protein (group 1), a concentrate containing 17.5% crude protein and 1 kg of fat-protein supplement Megapro Plus ® (group 2) or a concentrate containing 19% crude protein and 1 kg of fat-protein supplement Megapro Plus ® (group 3). The mean daily milk yield recorded in groups 2 and 3 amounted to 32.6 kg/dand was by 10.3% higher than in the control group (P ≤ 0.01). FCM yield increased by 15.5% and 12.1% in groups 2 and 3, respectively, in comparison with group 1. Diet supplementation with Megapro Plus ® had no significant effect on the levels of fat, lactose, protein, nitrogen fractions and urea, or some physicochemical properties of milk (density, pH, heat stability). A decrease was noted in solids-non-fat (group 2) and somatic cell count (P ≤ 0.05). Megapro Plus ® supplementation of a diet with a reduced (to 3%) "00" rapeseed meal content in concentrate (group 2) resulted in a significant increase in the concentrations of unsaturated fatty acids (especially C18:1 and C18:2) and hypocholesterolaemic acids (DFA) in milk, recorded on the 120th day of lactation. Megapro Plus ® supplementation of a concentrate with a high (10%) "00" rapeseed meal content aimed at increasing the concentrations of both energy and protein (group 3), had no significant effect on improvement in the fatty acid profile, i.e. changes towards increasing unsaturation of milk fat.

Thirty-two cows (Black-and-White x HF) in the first 100 days of lactation were divided into 4 groups and fed rations composed of equal proportions of roughages and concentrates in amount of 1 kg per 2 kg of milk at yield exceeding 12 kg/day. The concentrates were supplemented with vitamin E (group I, 336 mg; groups II, III, and IV, 672 mg/cow/day) and selenium: group I, no supplementation; group II, 4 mg/cow/day as sodium selenite; group III, 4 mg/cow/day as selenium yeast; group IV, 2 mg/cow/day as selenium yeast.Cows fed selenium-supplemented rations had significantly elevated serum selenium concentrations (group 1,0.0214 mcg/ml; II-0.0453 mcg/ml; III, 0.0654 mcg/ml; IV, 0.0573 mcg/ml). Selenium from yeast was utilized better than sodium selenite. Regardless of the source of selenium, Se lowered serum a-tocopherol (0.245 vs 0.229; 0.187; 0,232 mg/dl) and retinol (35.57 vs 31.46; 32.25; 29.29 mcg/dl) levels. The addition of selenium when the vitamin E content of the ration was increased modified the lipid metabolism of cows (elevated HDL and triglycerides).

Faba bean hulls fed at the rate of 18.3% DM of the diet decreased crude protein digestibility (P<0.01) and increased N-retention (3.8 g vs 5.5 g) in growing sheep. Significantly higher glucose level and decreased urea content in blood serum has been found within experimental animals.