The present study investigated the effects of Bacillus amyloliquefaciens (BA) supplementation
on the growth performance, intestinal integrity, antioxidant and immune status
of broilers challenged with lipopolysaccharide (LPS). 192 one-day-old male Arbor Acre
broilers were randomly distributed into four treatments: (1) non-challenged control; (2)
LPS-challenged control; (3) LPS-challenged group + 0.5 g/kg of diet; and (4) LPS-challenged
group + 1.0 g/kg of diet. Broilers were intraperitoneally injected with either 500 g/kg body
weight of LPS or sterile saline at 16, 18 and 20 d of age. The inclusion of 1.0 g/kg BA alleviated
the compromised average daily gain caused by LPS challenge, the body weight gain in
1.0 g/kg BA supplemented group was still significantly lower than that of control (P < 0.05).
Similarly, BA supplementation attenuated intestinal morphology impairment, and reduced
intestinal malonaldehyde concentration and myeloperoxidase activity after LPS injection
(P < 0.05). The 1.0 g/kg BA inclusion prevented the elevation of circulating diamine oxidase
activity and reduction of intestinal glutathione concentration induced by LPS challenge
(P < 0.05). The BA decreased interleukin (IL)-1, whereas increased IL-10 at both protein
and transcriptional levels in jejunum, and attenuated LPS-induced elevated mRNA expression
of jejunal toll-like receptor 4 (P < 0.05). Moreover, inclusion of 1.0 g/kg BA alleviated
LPS-induced negative effect on the mRNA abundance of tight junctions (P < 0.05). It can
therefore be postulated that BA supplementation alleviates LPS-induced intestinal mucosal
damage by improving intestinal integrity and antioxidant and immune status.