Replacement of Soybean Meal with Lupin or Chickpea Seed Meal in Diets for Fattening Iberian Pigs Promotes a Healthier Ileal Microbiota Composition

Abstract

Five castrated male Iberian pigs (100 ± 2 kg b.w.) fitted with T-shaped ileal cannulas at the terminal ileum were used to determine the effects of legume feeding on intestinal microbiota composition. The diets were based on defatted soybean ( Glycine max ), lupin ( Lupinus angustifolius ) or chickpea ( Cicer arietinum ) seed meals and contained similar amounts of digestible energy (14.2 - 15.1 MJ·kg -1 ) and protein (107 g·kg -1 ). A hydrolyzed casein diet was used to determine the bacterial counts in pigs fed on a vegetable-free diet. The composition of the intestinal microbiota at the terminal ileum was analysed by q-PCR. Higher ( P < 0.05) lactobacilli log 10 number of copies was determined in the ileal contents of pigs fed on lupin- or chickpea-based diets with respect to those fed on the soybean-based diet. Bacteroides and the Clostridium coccoides / Eubacterium rectale group log 10 number of copies was lower ( P < 0.01) than that of soybean in the ileal contents of chickpea-fed pigs. Enterobacteria and the Escherichia / Shigella group log 10 number of copies was lower ( P < 0.01) than that of soybean in pigs fed on diets based on lupin or chickpea. The number of copies of the different bacterial groups in animals fed on the casein-based diet was lower ( P < 0.01) than that of soybean for lactobacilli and bacteroides, but was higher than that of soybean for bifidobacteria, enterobacteria and the Escherichia / Shigella group. This information suggests that lupin or chickpea feeding might induce a benefit in the microbiota composition of Iberian pigs in their final productive stages.