Influence on the ileal and fecal digestibility of forages inclusion in the diet

Summary

The present investigation aimed to study the ileal and fecal digestibility of three forages (Clover grass, Clover grass silage and Pea-Barley silage) supplemented to a basal diet. A total of 24 pigs, adapted to eating forages by supplementing a basal feed with clover grass silage from weaning, were fitted with a T-cannula at the terminal ileum at approximate 30 kg LW. For each of the three types of forage, two balance trials with 4 weeks interval were carried out. Two pigs in each test were fed the basal diet while 6 others were fed the basal diet plus forage throughout the whole experiment. The intake of forages was relative low and quite variable and accounted on average for only 10-12 % of the daily dry matter intake. Ileal digestibility estimated by collection from the T-cannula was higher than the digestibility estimated by the slaughter technique indicating some separation of the digesta collected from the T-cannula. The forages had, as expected, a lower fecal DM and energy digestibility than the basal diet (P<0.05). The fresh clover grass had a higher energy digestibility than the two silages (60 vs 48 %, P<0.05). Inclusion of 10 % of gross energy in the diet from clover grass reduced the rations energy digestibility relatively by 2.2 %, while clover grass silage and the pea-barley silage to reductions of 3.4 and 5.0 % (P<0.05), respectively.