Thymol modulates rumen barrier function and inflammation in feed-restricted lambs.

Area of Science:

• Animal Science
• Nutritional Science
• Veterinary Medicine

Background:

• Severe feed restriction (SFR) negatively impacts rumen epithelial barrier function and inflammatory status in lambs.
• Thymol, a natural compound, possesses antimicrobial, antioxidative, and anti-inflammatory properties, suggesting potential benefits for gut health.

Purpose of the Study:

• To investigate the effects of thymol on rumen barrier function and inflammatory signaling pathways under severe feed restriction in lambs.
• To assess thymol's impact on tight junction protein expression and inflammatory cytokine levels in the rumen epithelium.

Main Methods:

• Thirty Baluchi ram lambs were divided into control, SFR, and SFR plus thymol (SFRT) groups.
• Thymol (300 mg/d) was administered to SFRT lambs during a 4-week feed restriction period, followed by 4 weeks of ad libitum feeding.
• Evaluated growth performance, ruminal fermentation, plasma metabolites, rumen histology, and mRNA expression of tight junction proteins and cytokines.

Main Results:

• SFR lambs exhibited reduced body weight during feed restriction but showed compensatory growth during ad libitum feeding.
• Thymol administration in SFRT lambs tended to increase volatile fatty acid concentrations and significantly reduced plasma haptoglobin levels.
• Thymol upregulated key tight junction proteins (Claudin-1, Occludin, ZO-1) and downregulated pro-inflammatory interleukin-6 mRNA expression in the rumen epithelium.

Conclusions:

• Thymol administration during severe feed restriction can help maintain rumen epithelial barrier integrity in lambs.
• Thymol effectively modulates inflammatory responses and tight junction protein expression in the rumen epithelium, mitigating the negative effects of feed restriction.