Plant extracts improves gut health by reducing the severity of E. coli challenge

Phytobiotics are plant-derived natural bioactive compounds that promote livestock health and well-being and improve production efficiency. The beneficial effects of phytobiotics may be explained by the activation of feed intake, the secretion of digestive enzymes, immune stimulation, intestinal microflora modulation, anti-bacterial effects and anti-inflammatory properties. This study investigated the effects of a novel plant extract (PE) product that was added to the drinking water on the performance and gut health in weaned piglets challenged with Escherichia coli. The PE was a standardised mixture of green tea leaves (Camellia sinensis) and pomegranate fruit (Punica granatum). A total of 144 piglets weaned at 24 days were used in the trial. Piglets were raised for 35 days in eight different groups with a 2×2×2 factorial design comparing different treatments (water without product (CT) or 8 μl/kg per day PE in the drinking water (PE)), feeding regimens (AD or restricted (RE)) and oral E. coli challenges on day 9 (sham (−) or infected (+)). Six pens per group with three piglets per pen were used. On day 35, a total of 24 piglets of the RE feeding were slaughtered.

The results showed higher average daily gain (ADG) for the PE group from day 28 to day 35 (P =0.03) and increased the gain to feed ratio (G : F) from day 7 to day 14 (P = 0.02). RE feeding led to lower feed intake in piglets during the 1st week (P<0.01), 2nd week (P = 0.06), 3rd week (P = 0.05), and throughout the course of the overall study period (P = 0.05). E. coli challenge decreased the ADG and G:F ratio from day 7 to day 14 (P = 0.08 and <0.01, respectively) and increased the faecal score on days 14, 21, 28 and 35 (P<0.01). PE supplementation decreased the faecal score in the challenged piglets during the 1st week post-challenge (P<0.01). Reduced faecal E. coli was observed on days 14 and 35 (P = 0.05 and 0.02, respectively), and reduced Enterobacteriaceae (P<0.01) was found on day 35 in the PE animals. RE feeding increased the faecal Lactobacillus, Enterobacteriaceae and E. coli levels on day 35 (P = 0.02, <0.01 and <0.01; respectively).

In conclusion, the use of a PE product improved gut health and microbial ecology in weanling piglets, thus reducing the severity of an E. coli challenge.