Effects of Lactobacillus acidophilus on the growth performance and intestinal health of broilers challenged with Clostridium perfringens

Background: Clostridium perfringens is the main etiological agent of necrotic enteritis. Lactobacilli show beneficial effects on intestinal health in infectious disease, but the protective functions of lactobacilli in C. perfringens-infected chickens are scarcely described. This study examined the effects of Lactobacillus acidophilus (L. acidophilus) on the growth performance and intestinal health of broiler chickens challenged with Clostridium perfringens (C. perfringens) over a 28-day period. Using a 2 x 2 factorial arrangement of treatments, a total of 308 1-day-old male Arbor Acres broiler chicks were included to investigate the effects of Lactobacillus acidophilus (L. acidophilus) on the growth performance and intestinal health of broiler chickens challenged with Clostridium perfringens (C. perfringens) during a 28-day trial. Results: During infection (d 14-21), C. perfringens challenge decreased the average daily gain (P < 0.05), and increased feed conversion ratio and the mortality rate (P < 0.05). However, dietary supplementation with L. acidophilus increased the body weight of C. perfringens-infected broilers on d 21 (P < 0.05), and tended to decrease the mortality (P = 0.061). C. perfringens challenge decreased the villus height (P < 0.05), the ratio of villus height to crypt depth (P < 0.05) and OCLN (occludin) mRNA expression (P < 0.05), and increased the pro-inflammatory cytokine expression in the spleen and jejunum, the intestinal populations of C. perfringens and Escherichia (P < 0.05), and the serum content of endotoxin (P < 0.05), regardless of L. acidophilus supplementation. In contrast, dietary L. acidophilus reduced the intestinal lesion score of challenged broilers (P < 0.05), the mRNA expression of pro-inflammatory cytokines, ileal populations of Escherichia and serum endotoxin content (P < 0.05), but increased the intestinal Lactobacillus populations (P < 0.05), irrespective of C. perfringens challenge. Conclusion: Dietary addition of L. acidophilus could improve the intestinal health and reduce the mortality of broilers suffering from necrotic enteritis.