Effect of feeding level, live weight and genotype on the apparent faecal digestibility of energy and organic matter in the growing pig

The effects of live weight and feeding level on apparent digestible energy (ADE) and apparent digestible organic matter (ADOM) in two cereal based diets, differing in their fibre content (wheat and wheat by-products) were studied using 48 Large White × Landrace entire male pigs. Pigs fed the low fibre diet (wheat) had higher ADOM and ADE (P<0.001) than those fed the high fibre diet (wheat by-product). The effect of ingesting the diets at 6 or 11% of metabolic live weight (W0.75) had no effect on ADOM and ADE. Heavier pigs (90 kg live weight) achieved slightly improved ADOM and ADE (P<0.05) relative to lighter pigs (25 kg live weight). No interactions between diet type, live weight and feeding level were observed.In a second experiment, the effect of genotype was studied using six 4-month-old Large White × Landrace entire male pigs (54 kg live weight) and six 3-month-old Kune-Kune entire male pigs (19 kg live weight). The ADE and ADOM were significantly higher (P<0.001) for the Kune-Kune pigs than for the Large White × Landrace with the high fibre diet (wheat by-product). However, no differences (P>0.05) in ADE and ADOM were observed between genotype for the low fibre diet (wheat).