the effects of different levels of biohebal® feed supplement (contains thymus and garlic extracts) on performance, egg traits and blood biochemical and immunity parameters of laying hens

this experiment was conducted to evaluate the effects of different levels of biohebal® feed supplement on performance, egg traits, blood biochemical and immunity parameters of laying hens. experiment was conducted in a completely randomized design with 144 of hy- line (w36) laying hens from 23 to 34 weeks of age in 4 treatment and 3 replicate (with 12 bird in each replicate) and included: control group without using bioherbal, an another groups the amounts of this herbal supplement were 0.05%, 0.1% and 0.15%. there were not significantly difference between control group and other treatments in performance, egg quality and blood biochemical parameters (p<0.05). however in therms of numerical the highest percents of egg production (91.50), haugh unit (98.17), lymphocyte (90.84), the highest amount of blood serum albumin (2.89), the lowest percent of heterophile and the lowest ratio of heterophile/lymphocyte (0.095) were observed in 4 experimental groups. the overall results of the present study indicate that in laying hens using 0.15 percent of bioherbal feed supplement can improve of performance, egg quality, blood biochemical and immunity parameters.