EN
The experimental fattening pigs (30-105 kg) were fed ad libitum diets containing rapeseed meal, according to The Nutrient Requirements of Pigs or the free-choice method (free access to two isoenergy diets with different protein concentrations). The experiment was performed on 24 crossbred pigs (♂ Duroc x ♀ Polish Landrace), divided into three feeding groups: group I fed a cereal-soybean diet (1) containing 15.6% of total protein, group II fed a cereal-rapeseed diet (2) containing 15.6% of total protein, group III fed according to the free-choice system, with constant access to diet (3) and diet (4), containing 12.6 and 18.6% of total protein respectively. The experiment was conducted in an experimental pig house. The pigs were kept in litter boxes, two animals in each. The production results obtained were similar in all experimental groups.