Effects of naturally oxidized corn oil on inflammatory reaction and intestinal health of broilers

This study was conducted to investigate the effects of naturally oxidized corn oil on the inflammatory reaction and intestinal health of broilers. Total 450, one-day-old Arbor Acres male broilers were randomly divided into 5 treatments with 6 replicate cages (15 birds in each replicate cage). The dietary treatment array consisted of the varying ratio of nonoxidized corn oil to naturally oxidized corn oil from 0:100, 25:75, 50:50, 75:25, and 100:0, respectively. The experimental period was 42 d. Serum, jejunum, and contents of cecum samples were taken at the age of 42 d of broilers. The results showed no significant difference in the body weight gain (BWG) with a different proportion of oxidized corn oil compared with the 0% oxidized oil group on d 42. The feed intake (FI), the concentration of immunoglobulin G (IgG), interferon-γ (IFN-γ), and interleukin-10 (IL10) in serum showed a significant quadratic response with the increase of oxidized oil concentration on d 42. The serum's concentration of IgG, IFN-γ, and IL-10 reached the highest value at 75% oxidized corn oil. In addition, the mRNA expression levels of interleukin-1β (IL-1β), IFN-γ, nuclear factor kappa B (NF-κB), tumor necrosis factor α (TNF-α), and myeloid differentiation factor-88 (MyD88) in the jejunum were significantly affected by different proportions of oxidized corn oil, and the gene expression levels were highest at 75% oxidized corn oil on d 42. The mRNA expression of Bcl2-associated X (Bax) in the jejunum showed a significantly quadratic curve with the increase of oxidized oil concentration, and its gene expression was the highest after adding 50% oxidized corn oil according to the regression equation on d 42. The villus height/crypt depth and goblet cells of jejunum decreased linearly with the increasing proportion of oxidized corn oil and reached the lowest point after adding 100% oxidized corn oil on d 42. The β diversity showed the remarkable differentiation of microbial communities among 5 groups, and the microbial community of the 0% oxidized oil group was significantly separated from that of 75 and 100% oxidized oil groups in the cecum. Taken together, these results showed that a low dose of naturally oxidized corn oil is not harmful to the growth of broilers, while a high dose of oxidized corn oil will trigger the inflammatory response and adversely affect the gut health of broilers.