STUDY ON BLOOD, IMMUNITY AND DIGESTIVE TRACT HISTOLOGY OF BROILER CHICKENS IN RELATION TO FEED FORM AND FEEDING PROGRAM

This experiment was conducted on 270-day-old broiler chicks using a 2×3 factorial arrangement. Two protein levels as feeding programs were compared, each program was combined with three feed forms (mash, crumble, and pellet), resulting in six treatment groups. Each treatment included three replicates of 15 birds, providing balanced experimental units. Data was analyzed using ANOVA, and differences among means were considered significant at p< 0.05. The study was designed to evaluate immune organ development, blood biochemistry, skeletal traits, and intestinal histomorphology. Results showed that feed form had a stronger influence than feeding program. Bursa percentage was significantly higher in birds fed pellets or crumbles, while spleen remained unaffected. The feeding program had minimal effects on blood parameters, except that reduced crude protein (CP) (program 2) increased cholesterol and alanine amino transferase activity. Feed form altered serum proteins, with mash-fed birds showing higher total protein and globulin, whereas crumble feeding lowered aspartate amino transferase, suggesting reduced hepatic stress. Bone traits were strongly affected by feed form as pelleted diets enhanced tibia length, width, and volume, while the combination of program 2 with pellets produced the greatest tibia breaking strength, reflecting a synergistic benefit. Intestinal morphology revealed that higher CP improved villus height, pellets promoted taller villi but reduced villus width/crypt depth ratio, mash increased goblet cell numbers, and crumbles enhanced crypt depth but lowered goblet cells. In conclusion, feed form was more decisive than feeding program in shaping immunity, metabolism, skeletal integrity, and gut morphology. Pellets and crumbles optimized growth and bone strength, while mash favored humoral and mucosal defense. Pelleting is recommended for performance, with