Determination of apparent total tract digestibility of nutrients of lucerne (Medicago sativa) and red clover (Trifolium pratense) products in growing pigs

In a digestibility trial with 24 growing pigs (Danish Landrace × Duroc; male, castrated) the apparent crude nutrient digestibility of organically produced lucerne and red clover products was determined. The products (dried lucerne leaf (LL): 198 g crude protein (CP) per kg dry matter (DM); lucerne leaf silage (LLS): 295 g CP/kg DM; lucerne whole plant silage (LS): 213 g CP/kg DM; red clover whole plant silage (RCS): 263 g CP/kg DM) were fed to the animals together with a compound feed adapted for the whole plant or leaf material. Titanium dioxide was added to this supplement, which was used as an inert marker for the digestibility calculation. Differences were found in feed intake throughout the sampling phase in the metabolic cages. The whole plant silages (LS: 53.6% digestibility of organic matter (dOM), 56.3% digestibility of crude protein (dCP); RCS: 69.9% dOM, 69.3% dCP) as well as the LLS (63.0% dOM, 58.0% dCP) showed a higher dOM and dCP than the LL (45.0% dOM, 42.7% dCP). It was suspected that the saponins, which are mainly enriched in the leaves, influence the feed intake and digestibility of the leaf products. The quality and method of preserving feed also affected digestibility test feedstuffs.