Dietary supplementation of Lactobacillus salivarius in suckling and weanling piglets modulates intestinal microbiota, morphology and improves growth performance

Suckling piglets face the hurdle of pathogenic inversion before the full development of their gastrointestinal tract. The provision of <italic>Lactobacillus(L) salivarius </italic>guarantees resilient gut health, controls pathogens, increases microbiota, and fortifies intestinal structure. We evaluated the effect of <italic>L. salivarius</italic> LS144 probiotic given to suckling piglets through the post-weaning stage on the gut microbiota, intestinal morphology, and growth performance. 120 three-day-old crossbred (Landrace × Yorkshire × Duroc) piglets were assigned to four dietary treatments on the basis of initial body weight. The NN group was not supplemented with the probiotic in both the suckling and post-weaning phases, the NP group was supplemented with the probiotic during the post-weaning phase, the PN group was supplemented with the probiotic only during the suckling phase, and the PP group was supplemented with the probiotic during both the suckling and post-weaning periods. Results revealed that the average daily gain was higher (<italic>p</italic>&lt;0.05) in the PN and PP groups than in the NN and NP groups in phase 1. In the overall study (1~51 d), average daily gain was greater (<italic>p</italic>&lt;0.05) in the PP treatment compared to all other groups. The average daily feed intake was higher (<italic>p</italic>&lt;0.05) in the PP group (22~ 51 d) than all groups. The villus height was greater in the duodenum (p&lt;0.05), jejunum (<italic>p</italic>&lt;0.05), and ileum (<italic>p</italic>&lt;0.05) in the PP compared with the NN. The pH of the intestinal digesta was higher (<italic>p</italic>&lt;0.05) in the NN treatment than in the PN and PP treatments in the duodenum. The population of total <italic>L. </italic>bacteria was greater in both the PN and PP groups compared to the NN treatment in the duodenum (<italic>p</italic>&lt;0.01), jejunum (<italic>p</italic>&lt;0.05), ileum (<italic>p</italic>&lt;0.01), and cecum (<italic>p</italic>&lt;0.01). There was no significant difference in the population of total anaerobes, Clostridium, and coliform bacteria in the duodenum, jejunum, ileum, and cecum among the groups. Based on these findings, dietary supplementation with <italic>L. salivarius</italic> in suckling piglets continued to post-weaning could establish appropriate intestinal microbiota, improve feed intake, and increase the villus height, which translates to improved growth performance during this critical period in piglet’s life.