The effect of condensed tannins in sainfoin (Onobrychis
viciifolia) and sulla (Hedysarum coronarium) on the digestion of amino
acids in sheep
E.N. BERMINGHAM, K.J. HUTCHINSON, D.K. REVELL, I.M. BROOKES AND
W.C. McNABB
Nutrition and Behaviour Group, AgResearch Limited, Palmerston
North, New Zealand
E-Mail:
Proceedings of the New Zealand Society of Animal Production 2001. 61:
116-119
Two experiments were conducted in order to compare the effect of
condensed tannins (CT) in sainfoin (Onobrychis viciifolia) and sulla
(Hedysarum coronarium) on the flux of amino acids (AA) through the
gastrointestinal tract of sheep. In each experiment, one group of sheep
(PEG group; CT inactive) received an intraruminal infusion of
polyethylene glycol (PEG) to inactivate the CT present in the forages,
while the other group received an intraruminal infusion of water (Tannin
group; CT active). The CT in sainfoin (38.1 g/kg DM) had no significant
effect on apparent AA absorption from the small intestine. However, in
the sulla-fed sheep, AA absorption in the small intestine was
significantly increased by CT (P<0.05; CT = 64.4 g/kg DM). In both
forages a shift in AA digestion from the rumen to the small intestine
was seen with increased abomasal fluxes of AA in the Tannin group of
sainfoin- (92 versus 101 g/day in the PEG and Tannin group,
respectively; P<0.05) and sulla-fed (65 versus 83 g/day; P<0.001)
sheep. Differences in the digestion and absorption of AA in the two
forages may be associated with differences in chemical structure of the
CT.
Keywords: NZSAPAB;
condensed tannins; amino acids; sheep; sulla; sainfoin
Last Updated 7/08/01
