Effects of complex probiotic supplementation in growing pig diets with and without palm kernel expellers on growth performance, nutrient digestibility, blood parameters, fecal microbial shedding and noxious gas emission.

In Experiment 1, a total of 100 growing pigs (Duroc × [Landrace × Yorkshire]) with an average initial body weight (BW) of 24.88 ± 1.57 kg were randomly allotted to 2 × 2 factorial arrangement with two concentrations of palm kernel expellers (PKE) in diets at 0% or 10%, and two concentrations of supplemental probiotics at 0 or 6.0 × 107  colony-forming units/kg. There were five replicate pens per treatment with five pigs per pen. In Experiment 2, eight barrows with average initial BW of 25.78 ± 0.19 kg were allotted to a replicated 4 × 4 Latin square design with four diets and four periods per square. Four experimental diets were the same as Experiment 1. In Experiment 1, dietary probiotic supplementation improved (P < 0.05) the average daily gain (ADG), nutrient digestibility and the fecal Lactobacillus counts. Furthermore, interactive effects (P < 0.05) between PKE and probiotics were observed on ADG and growth-to-feed ratio. In Experiment 2, an interactive effect (P < 0.05) of PKE and probiotics was observed in apparent ileal digestibility of nitrogen and some amino acids. In conclusion, dietary probiotics did not improve PKE utilization and the use of probiotics in non-PKE-containing diet was more favorable than in PKE-containing diet.