Zootechnical Additives Associated with Antimicrobials: Effects on Immune Response and Intestinal Histomorphometry in...

Area of Science:

• Animal Science
• Poultry Nutrition
• Immunology

Background:

• Antibiotic growth promoters (AGPs) are widely used in broiler production but face increasing scrutiny.
• Zootechnical additives offer potential alternatives or complements to AGPs for improving animal health and performance.

Purpose of the Study:

• To evaluate the synergistic effects of zootechnical additives combined with AGPs on broiler chicken performance.
• To assess the impact on immune parameters, intestinal morphology, and overall productivity.

Main Methods:

• 1400 Cobb 500 male broiler chicks were assigned to seven dietary treatments, including AGPs alone, AGPs with various zootechnical additives (prebiotics, probiotics, essential oils, organic acids), and a control.
• Evaluated parameters included weight gain, feed intake, feed conversion ratio, productive efficiency index, leukocyte differential activity, phagocytic activity, intestinal histomorphometry, and inside index.

Main Results:

• Treatments combining AGPs and zootechnical additives significantly improved weight gain, feed intake, feed conversion ratio, and productive efficiency index (p < 0.05).
• Phagocytic activity was reduced in birds without AGPs or with AGPs but no additives.
• Birds receiving AGPs with zootechnical additives showed poorer intestinal histomorphometry and lower inside index compared to controls.

Conclusions:

• Zootechnical additives can effectively enhance broiler performance and immune function when used in conjunction with AGPs.
• Essential oils demonstrated the most significant positive impact among the tested additives, suggesting their potential in broiler feed formulations.