Effects of Combinations of Postbiotics and Phytobiotics on Growth Performance, Meat Quality, Gut Morphology, and Tibia Bone Characteristics in Broiler Chickens

In the current study, the impact of the dietary combination of postbiotics and phytobiotics was examined on the growth performance, carcass characteristics, meat quality, gut morphology, and tibia bone characteristics of broiler chickens. This experiment was conducted in the Duhok government’s private-sector poultry house for 35 days. The broiler chickens were allocated into eight treatment groups. Each treatment had four replicates, while each replicate had twelve birds. The treatment groups included T1= basal diet (negative control), T2= basal diet + 0.01% (w/w) Doxin 200 (positive control), T3= basal diet + 0.3 % (v/w) postbiotic, T4= basal diet + 0.3% black cumin oil (v/w), T5= basal diet + 0. 3% thyme oil (v/w), T6= basal diet + 0.15% postbiotic + 0.15% black cumin oil (v/w), T7= basal diet + 0.15% postbiotic + 0.15% thyme oil (v/w), T8= basal diet + 0.15% postbiotic + 0.075% black cumin oil + 0.075% thyme oil (v/w). According to the results, adding postbiotics and phytobiotics to broiler feed significantly increased weight growth, feed conversion ratio, and economic index, particularly in birds in the T7 group. The meat traits had improved nevertheless and were now in the normal range. Additionally, gut morphological characteristics had improved and, particularly in bird groups given T7, had demonstrated the greatest rate of villa height/crypt depth (Vh/Cd) ratio and absorptive surface area. In contrast to broiler-fed antibiotics, the characteristics of the tibia bone were enhanced by a combination of postbiotics and phytobiotics. The greatest prospective substitute for antibiotic growth promoters in broiler chicken is the combination of 0.3% postbiotics and phytobiotics (thyme oil) as new feed additives.