The study was conducted to investigate the effects of graded dietary
inclusion levels of betaine on ileal and total tract nutrient digestibilities
and intestinal bacterial metabolites in piglets. A total of eight barrows
with an average initial body weight of 7.9 kg were randomly allocated
to one of the four assay diets with two pigs per treatment in four
repeated measurement periods. The assay diets included a basal diet
based on wheat, barley and soybean meal alone, or supplemented with
a liquid betaine product at dietary levels of 1.5, 3.0, or 6.0 g betaine per
kilogram diet (as-fed). Ileal digestibilities of dry matter and neutral
detergent fibre increased both quadratically and linearly, and ileal
digestibility of glycine increased linearly as dietary betaine level
increased (p < 0.05). Furthermore, total tract digestibility of crude pro-
tein increased quadratically (p < 0.05) and total tract digestibilities of
most amino acids tended to increase quadratically (p = 0.06 to p = 0.11)
with increasing dietary betaine level. Moreover, there were linear
increases in the concentrations of most bacterial metabolites which were
significant p < 0.05 for ileal d-lactic acid and for faecal diaminopimelic
acid. The results demonstrate that dietary betaine supplementation stim-
ulates bacterial fermentation of fibre in the small intestine and bacterial
degradation of crude protein in the large intestine
