A total of 48 crossbred pigs [♀(♀ Polish Landrace x ♂ Polish Large White) x ♂ (♀Pietrain x ♂ Duroc)] were used in the study. The pigs were divided into 4 experimental groups and placed in pens (size 4.2 m x 3.6 m) according to the following scheme: group I – kept with straw-bedding, fed concentrate diet and additionally given green Lucerne; group II – kept with straw-bedding, fed concentrate diet; group III – kept with straw-bedding, fed concentrate diet and additionally given green Lucerne; group IV – kept with straw-bedding, fed concentrate diet. The analysis of behavior of experimental pigs was performed twice during the course of experimental fattening, i.e. in the body weight ca 60 kg and ca 100 kg. The observations were performed daily in three two-hour sessions at 9.00–11.00, 12.00–14.00, 15.00–17.00. The recording of pig behavior was carried out by the means of supervision cameras and video recorders during the same day for each group separately. The housing system of pigs had an influence on their behavior. In the I phase of fattening the most active were the pigs kept without straw-bedding, they also ate concentrate diet more frequently in comparison with those kept on straw-bedding. In the II phase of fattening the animal of all experimental groups spent more time resting. The pigs kept without straw-bedding and fed only with concentrate diet were resting for the longest time. The share of other whole observation period was similar in all the experimental groups

21-32