Investigation on the effects of different levels of peppermint (Mentha piprita), thyme (Thymus vulgaris) and saturea (Satureia hortensis) medicinal plants on performance, egg quality, blood and immunity parameters of laying hens

This experiment was conducted to evaluate the effects of different mixtures of peppermint, thyme and saturea medicinal plants on performance, egg quality and blood biochemical and immunity parameters of laying hens. Experiment was conducted in a completely randomized design with 192 of laying hens in 4 treatments and 4 replicates (with 12 hen in each replicate) for 12 weeks and included: control group without using any medicinal plants, group 2 using 2% of medicinal plants (50% of peppermint, 25% thyme and 25% of saturea), group 3 (25% of peppermint, 50% thyme and 25% of sature) and group 4 (25% of pepermint, 25% thyme and 50% of sature). Results showed that the use of different medicinal plants mixture has significant effects on performance, biochemical parameters, percent of heterophils and ratio of heterophils to lymphocytes (p