Comparison of the effect of five herbal extracts and virginiamycin on serum lipids and heterophil/lymphocyte ratio in broilers

In recent years, we have paid special attention to the development and production of broiler chickens. In this regard, the use of medicinal plants has been considered as growth promoters. Hypolipidemic and antioxidant properties of medicinal plants and their extracts have been proved. The purpose of this study was to compare hypolipidemic effects of five herbal extracts and virginiamycin as growth promoters in the poultry industry. Seven hundred and twenty1-d-old male broiler chicks were randomly divided into 9 treatments and 4 replicates (20 birds per replicate). Treatments respectively included extracts of thyme (Thymus vulgaris), garlic (Allium sativum), common thyme (Thymus kotschyanus), common sage (Salvia officinalis), peppermint (Mentha piperita), blend of thyme and peppermint and blend of common thyme and common sage with a dosage of 1%, virginiamycin with dosage of 15 ppm and control. Total cholesterol (TC), LDL cholesterol, triglycerides (TG), HDL cholesterol, and heterophil/lymphocyte ratio were measured after 42 days. Among the extracts, garlic (Allivum sativum) significantly reduced the levels of TC, LDL, and TG and significantly increased the level of HDL. Heterophil to lymphocyte ratio was not affected by treatments and the highest and lowest ratios were respectively observed in treatments of peppermint and garlic. Herbal extracts could improve blood factors compared with the antibiotic and control groups.