Dietary anti- Escherichia coli K88 IgY enhances immune response and intestinal barrier function in piglets challenged with Escherichia coli K88.

BACKGROUND: Chicken egg yolk immunoglobulin Y (IgY) has shown potential in preventing pathogen infections. This study examined the effectiveness of dietary IgY supplementation at 6 g/kg in preventing weaned piglets from developing diarrhoea after a challenge with Escherichia coli K88 (E. coli K88). The experiment employed a 2 × 2 factorial design. Twenty-four healthy 17-day-old piglets with similar body weights (4.63 ± 0.39 kg) were selected and divided into 4 groups, each with 6 replicates (n = 6). The experimental period lasted 11 days. The control group (CON) and the E. coli K88 group (ECON) were fed a basal diet supplemented with 6 g/kg of common yolk powder. Meanwhile, the anti-E. coli K88 IgY group (IgY) and the E. coli K88 IgY group (EIgY) received a diet supplemented with 6 g/kg of anti-E. coli K88 IgY. From days 8 to 11 of the formal trial, piglets in the CON and IgY groups received an equal volume of normal saline (NS), while the ECON and EIgY groups were orally administered 10 mL of NS containing approximately 1 × 1010 CFU/mL of E. coli K88.

RESULTS: Results showed that dietary 6 g/kg anti-E. coli K88 IgY supplementation increased the IL-10 protein expression level in the jejunum tissue, villus height (VH), the villus height to crypt depth ratio (V: C), sucrase activities, and reduced colonic E. coli counts, diarrhea incidence, and D-LA levels in E. coli K88-infected piglets (P < 0.05). Meanwhile, the IgY diet increased Claudin-1 protein levels and decreased IL-8 levels in the jejunum tissue of E. coli K88-challenged piglets (P < 0.05).

CONCLUSIONS: The dietary 6 g/kg anti-E. coli K88 IgY supplementation can reduce intestinal structural damage and inflammation, improving growth by enhancing passive immunity and intestinal barrier function in E coli K88-challenged piglets.