Digestibility of whole ear corn silage used as ingredient of fattening diets for pigs

Fibrous feeds allow to increase satiety, health status and welfare of fattening pigs. Aim of the trial was to determine the digestibility of whole ear corn silage (ES) included at two levels (15 and 30 % DM, ES15 and ES30 respectively) in substitution of corn meal (C) in diets for pigs at different growth stages growth during the heavy fattening cycle. Six pigs were used in three digestibility trials, which were performed at 35, 85 and 135 kg average live weight of animals. Each trial was divided into two 14 d experimental periods, with the total faeces collected in the last 5 d. In each trial, during the first experimental period the pigs were grouped in three pairs, which received the three diets (C, ES15, ES30). In the second period the pigs of each pair were assigned to the two diets not received in the first period. Data were analysed per trial, according to a two period change-over design y=  + i + j + k +  ijk, ( = overall mean;   = period, diet and animal effects, i, j and k, 2, 3 and 6, respectively). The substitution of C with ES increased the NDF content of diets from 12.8 to 16.0 and to 19.2 % DM in diets C, ES15 and ES30. The DM content of faeces decreased regularly with the ES inclusion in all trials, but the reduction was statistically significant only in the third trial (29.9, 27.0 and 26.4 % DM, respectively for C, ES15 and ES30, P<0.05). In the first trial, the inclusion of ES affected negatively the digestibility of organic matter (88.9, 86.3 and 84.8 %, respectively for C, ES15 and ES30, P<0.01) and NDF (50.6, 45.5 and 41.2 %, respectively for C, ES15 and ES30, P<0.01). In the two subsequent trials, digestibility was not modified by ES inclusion. In conclusion, ES can be used at levels of 30% DM at intermediate and final fattening cycle without appreciable depressions of digestibility and with a reduction of faecal DM content. Further investigation have to asses the impact of ES on fattening and slaughter performances of heavy pigs.