Selenium has been known for two centuries and its biological activities have been studied for nearly a hundred years, however the problem of Se deficit has still been persisting both in humans and animals. The cause of Se deficit in animals may be low Se level in soil. This mainly applies to cattle and sheep with their direct link to soil via roughage. The risk of Se deficit in pigs and poultry is lower due to lower dependence on soil Se level in the region and Se fortification in feed mixes. The present research focuses on the effects of Se on meat and egg quality, antioxidant activity of Se, effects on fatty acid levels, activity of glutathione-peroxidase, or the effect of Se on the immune system. Ensuring natural Se supply in human nutrition by food of animal origin, mainly poultry meat and eggs (the "functional foods"), is another area to which extensive attention has recently been paid.

Sea buckthorn (Hippophae rhamnoides L.) is in the focus of interest mainly for its positive effects on health of both human and animal organisms. The whole plant of sea buckthorn and especially its berries are a source of a large number of different bioactive compounds. The greatest attention has been drawn to its high content of vitamins, minerals, natural antioxidants, n-3 and n-6 fatty acids, and proteins. Sea buckthorn is valued for its antioxidant, cardioprotective, antiatherogenic, antidiabetic, hepatoprotective, anti-carcinogenic, immunomodulatory, antiviral, antibacterial, anti-inflammatory and vasorelaxant effects. Due to these and other positive effects, the plant is included in both human and animal nutrition, in the latter case to increase the biological value of animal products. This review summarises the botanical characteristics of sea buckthorn, lists the bio-active substances contained in individual parts of the plant, their effects in the prevention of a number of different diseases and their possible utilisation in human and animal nutrition.

The development of new varieties of lupin, so-called "sweet lupinsˮ with low alkaloid (bitter substances) and high protein content has resulted in a renewed interest in utilization of lupin as source of proteins in human and animal nutrition. The nutraceutical potential of lupin can be applied in the prevention from various pathological states in humans; by suppressing appetite and affecting energy balance, by its positive effect on glycaemia and indicators of blood lipids, by its positive influence on hypertension and by improving defecation. In the field of animal nutrition, lupin seeds can positively affect both production indicators and the biological value of food of animal origin.

Amino acid content before and after heat treatment was assessed in grain of six selected amaranth varieties and four species: Amaranthus cruentus, A. hypochondriacus, A. caudatus and A. hybridus, cultivated in the Czech Republic. High content of Lys and Arg was detected in both heat treated and untreated grains, as well as satisfactory content of Cys and lower levels of Met, Val, Ile and Leu. The latter three amino acids appear as limiting. Chemical scores of essential amino acids and essential amino acid index (EAAI) were determined. EAAI value of 90.4% shows the favourable nutritional quality of amaranth protein, which is almost comparable with egg protein. Heat treatment by popping at 170 to 190°C for 30 s resulted in decreased EAAI to 85.4%. Of the essential amino acids under study, Val and Leu contents decreased significantly (P < 0.05). The relatively high content of essential amino acids in amaranth grain predetermines its use as a substitution of meat-and-bone meals.

The objective of this work was to verify the hepatoprotective effects of Silybum marianum seed cakes in feed mixtures used for the fattening of chicken broilers to heavier weights. Part of the experiment was to verify the preventive effect of such modified feed mixtures with the use of chlortetracycline medication. The experiment was carried out on 180 ROSS 308 broiler chickens. The chickens were fed complete feed mixtures containing 0.0% (K), 0.2% (P1 and 1.0% (P2) of Silybum marianum seed cakes. The cakes used contained 2.95% of silymarin. On the 44 th day of fattening half of the chickens from every group were supplied with chlortetracycline medicated water at a dose of 2 g·kg 1 live weight. The selected biochemical indices were observed: cholesterol (Chol), glutamyl transferase (GMT), aspartate aminotransferase (AST), and alanine aminotransferase (ALT). On the 52 nd day of the test, six chickens from each group were euthanized and their liver was taken for histological examination. Adding Silybum marianum seed cakes resulted in a non-significant decrease in the chickens' live weight and in the feed conversion in both experimental groups compared to the control group. The cholesterol levels were highly significantly lower (p < 0.01) on the 43 rd day in group P2, and significantly lower (p < 0.05) on the 52 nd day in group P1 when compared to the control group (K). Also the ALT and AST activity was lower (p < 0.01) in both experimental groups on the 22 nd day of the experiment. On the 52 nd day the lower activity (p < 0.01) was found only for AST in both experimental groups. In the chlortetracycline medicated group P2, cholesterol level (p < 0.05) as well as ALT activity and AST activity decreased (p < 0.01), compared to the medicated control group. Results of biochemical analyses were also confirmed by histological examination of the liver. Administration of silymarin reduced (p < 0.01) the content of lipids and increased the content of glycogen in the liver of both experimental groups.