The aim of this study is a comparative analysis of the costs of production of intensively and extensively fed porkers in view of the qualitative parameters of meat obtained after slaughter. The production experiment, which involved the parallel fattening of 3 groups of 30 porkers (fed intensively up to a weight of about 120 kg and extensively u...p to weights of about 100 kg and 120 kg), was carried out between 2011 and 2012 in a deliberately selected farm. The researchers assumed average prices of the means of production and prices of livestock pigs in individual meatiness classes noted in Poland in 2012. The fattening started when the animals weighed about 40 kg. The feeds used for extensive fattening contained less total protein, energy and basic exogenous amino acids, but more raw fibre. The analysis proved that the extensive production of porkers up to 100 kg in 2012 was not profitable. The most profitable production was the intensive production up to 120 kg (a profit of €0.100 per kg, whereas in the extensive feeding up to 120 kg the profit was €0.072 per kg. The porkers which were fed less intensively had a higher slaughter value, thinner fatback, higher dressing percentage and smaller content of fatback in the half-carcase, whereas their meat contained more water and less protein, fat and ash than the meat from the group of porkers fed with the mix richer in protein and energy.
The aim of the paper was to determine the influence of the fertilization level on the energy and economics efficiency of the production technologies of selected crops processed into bioethanol or biogas. There were investigated the following crops: rye, triticale, wheat, sugar beets, maize, sorghum, reed canarygrass and Virginia fanpetals. In t...he energetic efficiency the Energy Return on Energy Investment index (EroEI) was used. Apart from the ERoEI ratio, the Net Energy Value (NEV) ratio was also used. In the economics efficiency attitude, the Gross Margin (GM) was determined.The investigations proved that in general, the production technologies of crops where the lowest levels of nitrogen fertilization were applied proved to have the highest energetic efficiency. The highest economic efficiency was characterized by the production of corn for biogas. In the case of the production of bioethanol (all plants), ratios were on the verge of profitability or the lack of it showed.The analysis proved that the efficiency of the technologies of production of the crops to be processed into biogas is several times higher than the energetic efficiency of the technologies of production of the crops to be processed into bioethanol.