Background
In pig production, early and abrupt weaning frequently causes weaning stress, which manifests as oxidative damage, barrier disruption, and digestion and absorption capacity decline. Lycopene exhibits beneficial antioxidant capacity in both humans and other animal models.
Objective
The present study aimed to investigate the effects of lycopene supplementation on early weaning stress in piglets and the underlying mechanisms by examining the oxidative stress state, gut intestinal barrier function, and the gut microbiota.
Methods
Twenty-four 21-day-old weaned piglets (Duroc × [Landrace × Yorkshire], castrated males, 5.48 ± 0.10 kg initial body weight) were randomly assigned to two treatments. The piglets were fed a basal diet (control treatment) or a basal diet supplemented with 50 mg/kg lycopene (lycopene treatment) for 28 days. Serum lipid levels, serum and jejunum enzyme activities, jejunum morphology, mRNA and protein expression, and gut microbiota were determined.
Results
Compared with the control treatment, lycopene supplementation increased serum CAT activity (P = 0.042, 62.0%); serum TC concentration (P = 0.020, 14.1%); and jejunum SOD (P = 0.032, 21.4%) activity, whereas it decreased serum (P = 0.039, 23.0%) and jejunum (P = 0.047, 20.9%) H2O2 concentrations. Additionally, lycopene increased the mRNA and protein expression of NRF2 (214.0%; 102.4%) and CD36 (100.8%; 145.2%) in the jejunum, whereas it decreased those of KEAP1 (55.6%; 39.8%). Lycopene also improved jejunal morphology, increasing the villus height (P = 0.018, 27.5%) and villus/crypt ratio (P < 0.001, 57.9%). Furthermore, it increased the abundance of potentially beneficial bacterial groups, including Phascolarctobacterium and Parasutterella, and decreased that of potentially pathogenic bacterial groups, including Treponema_2 and Prevotellaceae_unclassified.
Conclusions
Lycopene supplementation strengthens intestinal barrier function and improves the gut microbiota in weaned piglets by regulating intestinal antioxidant signaling.
