Abstract
Background:
Feed additive supplementation for weight gain is a recent trend in poultry farming. Antibiotics, probiotics, and acidifiers are commonly administered to improve weight gain and health status. Understanding their specific effects on growth and hematobiochemical parameters is essential for broiler production optimization.

Aim:
This research aimed to investigate the effects of antibiotic, probiotic, and acidifier treatments on broiler growth progression and hematobiochemical alterations.

Methods:
Eighty 12-day-old broiler chicks were randomly divided into four groups: Group A (control), Group B (antibiotic-treated), Group C (probiotic-treated), and Group D (acidifier-treated). The respective feed additives were administered to groups B, C, and D, while group A received a standard diet without additives. Body weights were recorded weekly until day 33, and blood samples were collected for hematological and biochemical analysis on the final day.

Results:
A significant increase in body weight was observed for all treatment groups compared with the control group across all observation days. The antibiotic-treated group showed a substantial increase in the total erythrocyte count, hemoglobin, and packed cell volume compared with the other groups. The total cholesterol level was significantly reduced in the probiotic- and acidifier-treated groups, and the triglyceride level was remarkably decreased in the acidifier-treated group. Furthermore, high-density lipoprotein levels were significantly increased in the acidifier-treated group and decreased in the antibiotic-treated group. However, low-density lipoprotein was significantly increased in the treated groups. Additionally, the aspartate aminotransferase level was notably elevated in the antibiotic- and acidifier-treated groups, while all treatment groups showed a significant increase in alanine aminotransferase level compared to the control.

Conclusion:
Antibiotic, probiotic, and acidifier supplementation significantly enhanced weight gain in broilers compared with the control group. Among the treatments, antibiotics notably improved hematological parameters, whereas probiotics and acidifiers positively influenced lipid profiles. Overall, these feed additives had beneficial effects on growth and selected biochemical parameters, with varying impacts on hematological values.

Key words: Antibiotic, Probiotic, Acidifier, Growth performance, Hematobiochemical profile