Nano-Encapsulated Cumin Oil and Bacillus subtilis Enhance Growth Performance, Immunity, Oxidative Stability, and...

Area of Science:

• Animal Science
• Nutritional Science
• Microbiology

Background:

• Heat stress negatively impacts rabbit performance, health, and gut integrity.
• Dietary strategies are crucial for mitigating heat stress in livestock production.
• Nano-encapsulated cumin oil and Bacillus subtilis are potential feed additives for improving animal health.

Purpose of the Study:

• To evaluate the efficacy of nano-encapsulated cumin oil and Bacillus subtilis, alone or in combination, in alleviating heat stress in growing rabbits.
• To assess the impact of these supplements on rabbit performance, carcass characteristics, and health indicators.
• To investigate the effects on digestive enzyme activity, nutrient digestibility, oxidative status, immunity, and gut health.

Main Methods:

• Eighty-four growing New Zealand White rabbits were fed for 42 days with a basal diet or diets supplemented with nano-encapsulated cumin oil (NECO), Bacillus subtilis (BS), or a combination (BSNO).
• Rabbits were housed under conditions simulating heat stress.
• Performance (body weight gain, feed conversion ratio), mortality, carcass traits, digestive enzymes, nutrient digestibility, oxidative markers (SOD, MDA), immune parameters (IgA, IgG, T3, T4), and gut health indicators (pathogenic bacteria, gene expression of IL-6, CAT-1, IL-10, MUC-2) were analyzed.

Main Results:

• The BSNO group showed significantly improved body weight gain, carcass weight, and feed conversion ratio, with reduced mortality (p < 0.05).
• BSNO supplementation enhanced trypsin secretion, nutrient digestibility (protein, fiber), oxidative stability (higher SOD, lower MDA), and immune response (higher IgA, IgG, T3, T4) (p < 0.05).
• Gut health was improved, evidenced by decreased pathogenic bacteria, down-regulated IL-6, and up-regulated CAT-1, IL-10, and MUC-2 gene expression (p < 0.05).

Conclusions:

• Combining nano-encapsulated cumin oil and Bacillus subtilis is an effective strategy to counteract the adverse effects of heat stress in growing rabbits.
• This dietary approach enhances rabbit performance, gut integrity, and immune function under heat stress conditions.
• The findings support the use of BSNO as a promising supplement for improving rabbit resilience to heat stress.