a1 School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch, WA 6150, Australia
a2 Department of Agriculture and Food, Animal Research and Development, Department of Agriculture and food, Locked Bag No. 4, Bentley Delivery Centre, WA 6983, Australia
An experiment was conducted to determine whether adding oat hulls to weaner pig diets based on extruded rice or unprocessed wheat influenced post-weaning diarrhoea (PWD) and protein fermentation in the large intestine. Ninety-six male piglets (5·16 (sem 0·08) kg) were allocated to (i) extruded rice plus animal proteins (RAP); (ii) RAP with added oat hulls (20 g/kg); (iii) wheat plus animal proteins (WAP); (iv) WAP with added oat hulls (20 g/kg). Blood and faecal samples were collected on days 7 and 14 after weaning at about age 21 d. Pigs fed RAP had more PWD than pigs fed WAP (P < 0·05). Oat hull supplementation to diet RAP decreased the incidence of PWD (P < 0·05). The total-tract digestibility of DM, starch and energy was higher in rice-based diets than in wheat-based diets (P < 0·001); however, oat hulls decreased digestibility of DM and gross energy (P < 0·001). Pigs fed RAP had higher plasma creatinine concentrations (P < 0·01), which were positively correlated to cumulative β-haemolytic Escherichia coli scores after weaning (R2 0·928; P = 0·015). Addition of oat hulls decreased plasma urea concentrations only in pigs fed RAP (interaction; P < 0·05). Pigs fed RAP had lower faecal total biogenic amine concentrations than pigs fed WAP (P < 0·001). Oat hull supplementation tended to decrease total biogenic amine concentrations (P = 0·103). These data indirectly suggest that a mostly insoluble dietary fibre source such as oat hulls can decrease PWD in dietary situations where there may be a misbalance of carbohydrate to protein entering the hindgut.
(Received May 21 2007)
(Revised October 09 2007)
(Accepted October 15 2007)
(Online publication November 28 2007)
Abbreviations: CP, crude protein; DE, digestible energy; OH, oat hulls; PWD, post-weaning diarrhoea; RAP, extruded medium-grain rice plus animal proteins; TTAD, total-tract apparent digestibility; WAP, wheat plus animal proteins