Analyses were conducted on 10 grass species from permanent grasslands in the Noteć Leniwa and Noteć Bystra valley. Their chemical composition was assayed, and their heat of combustion and heating value were determined. The cellulose content ranged from 33.38% to 38.68%, while the content of lignin ranged from 15.42% to 21.99%, and that of hemicellulose from 30.27% to 34.31%. The heating value of grasses was comparable to that of wood from 2- to 3-year-old willows and other fast-growing energy crops. However, the calorific value of naturally dried grasses may be slightly lower. The quantities of minerals in these grasses, exceeding those in wood, did not result in a lowering of their heat of combustion. The analyses clearly showed that the investigated grass species may be successfully used for energy generation purposes.

The Effect of a Protein-Xanthophyll Concentrate from Alfalfa (Phytobiotic) on Animal Production - A Current Review: One of the supplements that can replace antibiotic growth promoters is a protein xanthophyll extract from the leaves of alfalfa. Green matter of alfalfa contains 17-22% of total protein, rich in non-essential (exogenous) amino acids, saturated, monounsaturated and polyunsaturated fatty acids, vitamins, minerals, and organic acids. The crude fibre content in green matter of alfalfa is relatively high (about 23.0-30.0% dry weight). However, protein-xanthophyll extract (EFL) contains about 1-2% of crude fibre. Like the whole plants of alfalfa, the protein-xanthophyll extract contains secondary metabolites such as plant phytoestrogens (isoflavones and coumestrol) and antinutritional components (phytates, L-canavanine and saponins). Protein-xanthophyll concentrate (PX) as a natural feed supplement has a positive effect on animal organisms. When supplemented to animals, this extract enhanced production results, increased feed efficiency, and improved the quality of meat, milk and eggs. Also, PX reduced methane emissions and soil pollution with nitrogen compounds when used in animal nutrition. The aim of this review was to gather the current literature describing the effects of using protein-xanthophyll extract in animal nutrition.

In Poland, half of the grassland is neglected and requires renovation, which was the reason for starting this research project. The aim of this research was to study the grassland habitat of lowland central Poland that has water-deficient, slightly acidic mineral soil, in the years 2013–2016. Specifically, the impact of three methods of grassland renovation on the dry matter yield and the weight of post-harvest residues, as well as on the content of particular nutrient components in the soil, were determined. Three legume–grass mixtures were used for the renovation. The study shows that the method of renovation (ploughing, harrowing, and herbicide + direct sowing) did not have a significant effect on the dry matter yield nor on the weight of the post-harvest residues or the content in the soil of some nutrients. The highest yield was obtained from the “Original” mixture with 50% of legumes in the seed mix. After the renovation, 5.03–7.17 t·ha⁻¹ of post-harvest residues were obtained (mainly grasses and roots of plants, 68.7–71.1%). After three years from renovation, the soil pH significantly decreased and the content of Ca and Mg increased, while the nitrogen, phosphorus, potassium, and C_org compounds remained at an unchanged level. The concentration of various forms of nitrogen, P₂O₅, K₂O, Ca, and C_org decreased in the deeper soil layer (down to 60 cm).