Microencapsulated oregano essential oil improves growth performance, carcass characteristics, and meat quality in broiler chickens.

BACKGROUND AND AIM: The increasing restrictions on antibiotic growth promoters have intensified the search for safe and effective phytogenic alternatives for poultry production. Oregano (Origanum vulgare L.) essential oil (OEO) possesses antibacterial, antioxidant, anti-inflammatory, and immunomodulatory activities, but its high volatility and poor thermal stability limit practical applications. This study aimed to develop microencapsulated OEO and evaluate its effects on growth performance, carcass characteristics, and meat quality in broiler chickens. MATERIALS AND METHODS: OEO microcapsules were prepared by complex coacervation using gelatin and gum Arabic as wall materials. Physicochemical characteristics were evaluated through encapsulation efficiency, oil loading capacity, particle size analysis, Fourier-transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry, and release behavior studies. A feeding trial involving 3,600 one-day-old Arbor Acres broilers was conducted for 42 days. Birds were randomly allocated to four dietary treatments containing 0, 80, 120, or 160 mg/kg microencapsulated OEO. Growth performance, slaughter traits, meat quality parameters, and proximate composition of breast and thigh muscles were determined. RESULTS: The optimized microcapsules exhibited an encapsulation efficiency of 84.2%, a product yield of 82.37%, and a mean particle size of 151 μm. Structural and thermal analyses demonstrated effective encapsulation and enhanced thermal stability with sustained-release properties. Dietary supplementation with microencapsulated OEO improved broiler performance in a dose-dependent manner. Birds receiving 160 mg/kg supplementation exhibited significantly greater final body weight and average daily gain, together with reduced feed-to-gain ratio and mortality rate (p < 0.05). Breast muscle yield increased, whereas abdominal fat percentage decreased significantly (p < 0.05). Supplementation also improved meat quality by increasing muscle pH, reducing drip loss, enhancing redness, and decreasing lightness. Furthermore, breast muscle crude protein content increased, whereas crude fat content in breast and thigh muscles decreased significantly (p < 0.05). CONCLUSION: Microencapsulation using gelatin and gum Arabic effectively enhanced the stability and controlled-release properties of OEO. Dietary inclusion of 160 mg/kg microencapsulated OEO improved growth performance, carcass characteristics, and meat quality while reducing fat deposition in broilers. These findings indicate that microencapsulated OEO represents a promising phytogenic feed additive and a potential alternative to antibiotic growth promoters in sustainable poultry production.