The Efficacy of a Phytogenic Blend Against Induced Heat Stress in Broilers

Objective: This study aimed to evaluate the efficacy of a phytogenic additive containing extracts of Mangifera indica, Citrullus lanatus, Cymbopogon citratus, Allium cepa, Rosmarinus officinalis and Allium sativum to mitigate heat stress in broilers. The effects of phytogenic additive on growth performance, hematological parameters and stress biomarkers, such as HSP70 and cortisol (CORT) in feathers, intestines and heart tissues, were assessed. Materials and Methods: A total of 80 one-day-old Cobb 430 Y broilers (initial weight: 48.2±0.3 g) were divided into four groups, with two replicates per group: Normal Control (NC), NC+API, Heat Stress (HS) and HS+API. The test product termed ‘API’ used was plant extract blend. Heat stress was induced by exposing birds to 40°C using 100-watt bulbs, while the NC groups were kept at 30°C. In the 3rd week, after a 14-day acclimatization period, API (1 mL/L) was provided via drinking water. Feed was withdrawn between 12:00 and 16:00 hrs and water was available ad libitum. Results: The NC+API group showed significantly (p<0.05) better growth and hematological parameters compared to the other groups. The HS+API group showed a significant (p<0.05) increase in body weight compared to the HS group. Cortisol levels were highest in the HS group and lowest in NC+API. The HS group exhibited the highest leukocyte count, HSP70 and CORT levels, indicating maximum stress. Conclusion: Overall, the NC+API group performed better than those of the others, while the HS+API group reduced stress biomarkers more effectively than the HS group.