The Influence of Various Guar Meal Types on Growth Performance, Carcass Composition and Histology of the Liver of Broiler Chickens

This study evaluated how various types of guar meal in diets of broiler chickens affect their rearing results, carcass composition, and liver histology. The experiment was conducted in one hundred sixty Ross 308 broilers randomly allocated to four groups consisting of the same number of birds (C, GM1, GM2, and GM3). The birds were reared for over 42 days and fed with starter (days 1–21), grower (days 22–35), and finisher (days 36–42) rations. All feed rations were prepared using maize meal, soybean meal, oil, mineral, and feed additives. The experimental factor was guar meal type included in feed rations (starter, grower, and finisher stage) at 6% each: C (control group)—without guar meal, GM1—raw guar meal, GM2—Microlam, and GM3—roasted guar meal. Microlam is a high-protein animal feed produced by laminating and micronizing guar meal for enhanced digestibility and protein content, while roasted guar meal (also called korma) is a more basic protein supplement for livestock and poultry that has undergone roasting to improve its taste and digestibility. It was shown that 6% of raw guar meal in the feed rations affected significantly higher (2646 g) body weight of broilers in comparison to birds fed the same amount of Microlam (2583 g), however feed conversion ratio were similar (1.63–1.65 kg/kg; p > 0.05) in all groups. Thus similar musculature and fatness, broiler chickens from GM1 and GM2 groups obtained higher dressing percentage in compare to group GM3 (p ≤ 0.05). No significant effect of guar meal on the physical characteristics (except pH1), or the results of the proximate composition of the breast muscles was found. Rations fed to broiler chickens had no effect on the microscopic image of the liver or reaction to the presence of neutral fats. In summary, 6% inclusion of raw guar meal should be recommended in broiler chicken diets as a partial substitute for soybean meal because it contributes to achieving the best growth performance results as well as dressing percentage, without deterioration carcass composition, and liver histology.