Abstract

Heat stress negatively affects the broiler chickens’ productivity and well-being. This study was carried out to assess the effect of dietary palm oil inclusion on the growth performance, thermotolerance, biochemical parameters, and welfare of broiler chickens raised in tropical climates. A total of 500 broiler chickens aged 15 days were divided into four treatments, each consisting of five replicates with 25 chickens per replicate in a randomized design. The control group was fed a standard diet without palm oil (T), and the remaining diets contained palm oil at the inclusion levels of 1 (P1), 2 (P2), and 3 (P3). During the 4 weeks of experimentation, daily temperature and relative humidity in the poultry house were measured by thermo-hygrometers, and growth performance was weekly recorded. At 45 days old, six broiler chickens were slaughtered with measurements taken for carcass compositions and intestinal length. At 42 days of age, blood samples were collected for the Triiodothyronine (T3) and Thyroxine (T4) hormones, biochemical profiles, and Heterophil: lymphocyte (H/L) ratio assessment at the Regional Center of Excellence on Avian Sciences. Gait abnormality and litter quality were assessed at 38 days of age. The results indicated that the incorporation of 1 palm oil improved the growth performance of chickens compared to other groups. Similarly, the concentrations of T4 and T3 were higher in the 1 palm oil group. Triglycerides and total protein concentrations were higher in the broiler chickens of the control group, compared to other treatment groups. The dropping weight and gait score decreased with the increasing rate of palm oil. The results suggest that palm oil can be a beneficial dietary supplement for broiler chickens, particularly under heat-stress conditions. The incorporation of 1 palm oil contributes to the improvement of growth performance and the well-being of broiler chickens in tropical climates. However, it is crucial to consider the appropriate level of palm oil inclusion, as higher levels may have adverse effects, such as increased mortality. © The Author(s) 2024