Aidin dokht niknia - Department of animal science,Islamic azad university,kashmar,Razavi khorasan province,I.R.Iran

The objective of this study was to investigate the performance and gut health in coccidiosis challenged broilers fed diet supplemented with a blend of thymol and carvacrol. Theexperiment was carried out in a completely randomized design. Chickens were fed starter (1- 10 d), grower (11-24 d) and finisher (25-42 d) diets. During the experiment the chicks wereallocated to 3 experimental groups: T1) negative control (NC) diet: without challenge andadditive; T2) positive control (PC) diet: with Eimeria tenella challenge and without additive; and T3) with mentioned challenge+a blend of thymol and carvacrol (0.01 g/kg). Eachexperimental group was divided into 5 replicates consisting of 12 chicks each. At the end of experiment, body weight gain (BWG), feed intake and FCR were recorded and also two birds/replicate were randomly selected and euthanized by cervical dislocation to assess theintestinal histomorphology, microflora and coccidial lesion scores. Data showed that in comparison with the PC group, the BWG and FCR were improved (P<0.05) when the blendof thymol and carvacrol was added. Dietary supplementation of the phytogenic essential oil increased the beneficial population of ileal lactobacilli and bifidobacteria and decreased E.coli pathogen (P<0.05) as compared to PC group. Coccidiosis challenged birds treated withthe essential oil mixture demonstrated (P<0.05) the longer and wider villus accompanying deeper crypt and more goblet cells than the PC-treated birds. Inclusion of this additive to the PC diet suppressed (P<0.05) the intestinal lesion scores. However, the NC group induced thehighest BWG and lowest FCR, the favorite ileal microflora, the optimal villus growth and the least intestinal lesion scores in birds due to this group was not exposed to the challenge. Inconclusion, the application of the blend of thymol and carvacrol was efficient in coccidiosis challenged birds by enhancing performance and gut health (P>0.05).

broiler, carvacrol, coccidiosis, performance, thymol