Physiological, molecular, and immune responses to milk thistle extract administration in goats during peripartum period

Background Using natural compounds as additives in livestock nutrition could be a new goal in livestock production. Milk thistle extract is rich in bioactive compounds such as silymarin, which act as a strong antioxidant agent. Objective The current study aimed to investigate the metabolic profile, oxidative statue, and immune response after milk thistle extract administration in goats during the peripartum period. Materials and methods Multiparous pregnant Egyptian Nubian goats (n=16) were allocated into four experimental groups. The first group was kept as the control group. The second group was administrated milk thistle extract (10 g/day), whereas third and fourth groups were administrated 20 and 30 g/day for 4 months, respectively. Blood biochemical parameters were measured using colorimetric and enzyme-linked immunosorbent assay. Gene expressions of antioxidant genes [catalase (CAT), superoxide dismutase (SOD1, SOD2), glutathione peroxidase (GPX1), and peroxiredoxin 2] and transcription factor (nuclear factor erythroid 2 related factor 2) were evaluated using quantitative real-time PCR. Results and conclusion Biochemical parameters (total protein, glucose, total lipids, total cholesterol, triglycerides, high-density lipoprotein, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, urea, creatinine, triiodothyronine, and thyroxine) in plasma of groups administrated with milk thistle extract did not significantly differ compared with the control group. Milk thistle extract at high levels (20 and 30 g/day) significantly increased the level of activity of antioxidant enzymes (SOD, CAT, and GPX), total antioxidant capacity, and total immunoglobulin in cases compared with the control group. Moreover, milk thistle extract (20 or 30 g/day) significantly decreased the level of malondialdehyde (lipid peroxidation biomarker) and tumor necrosis factor alpha (inflammatory biomarker) in cases compared with the control group. The results indicated a significant increase in transcript abundance of CAT, GPX1, and SOD1 mRNA in the three groups administrated with milk thistle extract compared with the control group. However, mRNA expressions of SOD2, peroxiredoxin 2, and nuclear factor erythroid 2 related factor 2 were significantly up-regulated after administration with milk thistle extract at high levels (20 and 30 g/day). Milk thistle extract exerts antioxidant, anti-inflammatory, and immune-modulator effects during pregnancy and lactation in goat and maintained normal physiological functions.