Dietary Hydroxytyrosol Supplementation on Growth Performance, Gut Morphometry, and Oxidative and Inflammatory Status in LPS-Challenged Broilers

Abstract

This study assessed the effects of hydroxytyrosol (HT) on 8- to 20-day-old broilers challenged with lipopolysaccharide (LPS); 180 Cobb500™ male chicks were randomly assigned to 3 treatment groups, each comprising 10 replicates with 6 birds per replicate. Treatments included a control diet (CON), CON with LPS administration, and CON + LPS supplemented with 10 mg of HT/kg of feed. LPS was administered intraperitoneally on days 14, 16, 18, and 20. Body weight (BW), body weight gain (BWG), and the feed conversion ratio (FCR) were measured. On day 20, ten birds per treatment were slaughtered for analysis. Bursa, spleen, and liver were collected, and their respective relative weight was determined. The jejunum was destined for morphological analyses of villus height (VH), crypt depth (CD), and their ratio (VH:CD), and for mRNA expression of nuclear factor kappa B (NF-κB), catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), and interleukins 10 (IL-10), 1 beta (IL-1β), and 8 (IL-8). HT improved BW, BWG, and FCR, and reduced crypt depth (CD) while increasing the VH:CD ratio in the jejunum. Moreover, HT downregulated mRNA expression of CAT, GPx, IL-10, and IL-1β. In conclusion, HT enhances broiler growth performance, mitigates jejunal mucosa damage from LPS, and modulates antioxidant and immune responses.

Keywords: antioxidant; feed additives; gene expression; jejunum; lipopolysaccharide.

Figure 1

Effects of hydroxytyrosol supplementation on mRNA expression in the jejunum of broilers at 20 days old: (A) CAT, p value = 0.03; (B) GPx, p value = 0.0004; (C) IL-10, p value < 0.0001; (D) IL–1β, p value = 0.022; (E) IL–8, p value = 0.213; (F) NF–κB, p value = 0.633; and (G) SOD, p value = 0.315. Bars with different letters, along with their corresponding standard errors of the mean, differ from each other by the Tukey test. CON: control diet; CON + LPS: CON with LPS administration; HT + LPS: CON supplemented with 10 mg of hydroxytyrosol/kg of feed with LPS administration. CAT: catalase; GPx: glutathione peroxidase; IL–10: interleukin 10; IL–1β: interleukin 1β; IL–8: interleukin 8; NF–κB: nuclear factor kappa B; SOD: superoxide dismutase.