In Experiment 1, 28 boars were fed one of 4 dietary treatments:
T1) barley-based diet;
T2) barley-based diet plus ES;
T3) oat-based diet and
T4) oat-based diet plus ES.
The ES used in both experiments contained endo-1,3-β-glucanase and endo-1,4-β-xylanase.
Results Exp. 1
In Experiment 1, pigs offered barley-based diets had higher coefficient of total tract apparent digestibility (CTTAD) of organic matter (OM) and gross energy (GE) and lower CTTAD of nitrogen compared to oat-based diets.
Pigs offered barley-based diets had higher molar proportions of butyric and propionic acids and higher total VFA concentrations in the caecum and colon than pigs fed oat-based diets.
Pigs offered oat-based diets had higher populations of Bifidobacteria in the ileum and colon, and Lactobacilli in the colon compared with pigs fed barley-based diets.
Glucans effect
In Experiment 2, 28 boars were also fed one of 4 dietary treatments:
T1) oat-based diet containing endogenous (non-purified) β-glucans;
T2) oat-based diet containing endogenous β-glucans plus ES;
T3) wheat-based diet and exogenous (laboratory purified) β-glucans and
T4) wheat-based diet and exogenous β-glucans plus ES.
The laboratory purified exogenous β-glucans used in Experiment 2 were oat-derived β-glucans.
The diets were equalised to have similar amount of total β-glucan and arabinoxylan.
Results Exp. 2
In Experiment 2, pigs offered diets containing endogenous β-glucans without ES had higher populations of Bifidobacteria compared to pigs offered diets supplemented with exogenous β-glucans without ES.
Diets containing endogenous β-glucans without ES had a lower CTTAD of organic matter and gross energy compared to diets supplemented with exogenous β-glucans without ES.
Conclusion
Barley-based diets have more beneficial effects on parameters related to gut health than oat-based diets; however oat-based diets exhibit higher potential to enhance beneficial microbial populations.
Endogenous β-glucans show better prebiotic properties than exogenous β-glucans.