Cereal grains are often subjected to physical processing before being fed to equids. However, little information is available on how physical processing of cereals affects degradation dynamics in equids. This experiment examines the effect of two physical processing methods (micronisation and extrusion) on in situ degradation of barley in the caecum of ponies
Three caecally fistulated mature Welsh-cross pony geldings (approx. LW 270kg) were offered ad libitum grass hay plus minerals. Incubation bags (monofilament polyester 6.5 x 20cm, 41μm pores, 16mg/cm2 sample size) containing either unprocessed barley (UB), micronised barley (MB) or extruded barley (EB) were incubated in the caecum for fixed times according to both a forward (0, 2, 4, 6, 12, 8, 24, 48h) and reverse (48, 24, 8, 4, 12, 6, 2, 0h) incubation sequence. For each feedstuff residues from each time were bulked within pony and across incubation sequence for subsequent analysis of dry matter (DM) and starch (STC). Degradation profiles were fitted to the DM and STC disappearance data according to Ørskov and McDonald (1979).