Effect of peppermint extracts inclusion in broiler chick diet on chick performance, plasma constituents, carcass traits and some microbial populations, enzymatic activity and histological aspects of small intestine

Abstract

Background: Considerable attention has been directed to including medicinal herbs and those extracts as replacers for antibiotic growth promoters in broiler diets due to the cross and multiple resistance effect of antibiotic preparations on different microbial population in small intestine and hence negatively affect the health of poultry-product consumers. Methodology: One hundred and eighty broiler chicks were used to evaluate the effect of dried Peppermint (Mentha piperita) leaves and oil inclusion in broiler diets on chick performance, carcass traits and some microbial, enzymatic and histological measurements of small intestine. Chicks fed on 6 experimental diets (starter and grower) represents; basal diet that was taken as control treatment, then supplemented per kg with 1.5 g Peppermint Leaves (PL1.5), 3.0 g Peppermint Leaves (PL3.0), 125 mg Peppermint Oil (PO125), 250 mg Peppermint Oil (PO250) or 1 g flavomycin (AGP) as a commercial antibiotic preparation. Results: Results of concerned study revealed the followings; feed conversion rate significantly improved with control and PO125 groups during starter period and with PO250 and AGP groups during grower and overall periods. Carcass traits didn’t differ between treatments, except gizzard percent that increased with all peppermint extracts. AGP and all Peppermint treatments positively increased plasma total protein, total cholesterol, globulin and affect liver enzymes but with unclear trend. All PO and AGP treatments slightly improved the immunity indicator of chick plasma. All peppermint extracts tended to increase counts of lactobacilli and decrease common pathogenic bacteria of small intestine and enhanced the activity of stomach protease and ileal amylase and protease. Tested peppermint extracts showed a desirable effect on ileal villus height and crypt depth. Conclusion: The PO250 diet exhibited the best desirable results for most tested parameters compared with tested antibiotic preparation and the other experimental treatments.