An experiment was conducted with 64 weaned pigs (24 kg) to evaluate the
effect of different fibre sources on N excretion and the fermentation
metabolites produced in the gastrointestinal tract. The diets were balanced in
energy and amino acids with soy protein isolate, pea starch, sucrose and a
premix and supplemented with wheat bran, cellulose, peas, pea hulls, pea
inner fibre, sugar beet pulp, flaxseed meal (FSM) or corn DDGS, as fibre
sources. Fecal samples were collected for 3 consecutive days from d10 and
pigs were slaughtered on d16. Digesta from ileum and colon were collected
and analyzed for their short-chain fatty acids (SCFA) and ammonia content.
When wheat bran was the reference ingredient, the total tract N digestibility
was lower with FSM and DDGS (72 and 74% respectively) and higher in pea
hulls (81%) and pea inner fibre (79%). This, in turn affected the amount of
faecal N excreted, the latter being higher with FSM and DDGS (280 and 262
g/kg N intake respectively). The pea- and pea hull-based diets had higher
SCFA at the ileum level, while no difference in SCFA concentration was observed among diets in the
colon. Higher ammonia concentration was also found in the colon of pigs fed
with peas, pea hulls, FSM and DDGS, which might adversely affect the pig’s
gut environment.