Effect of Garlic and Thyme’s essential oils blend as a feed additive after feed restriction on the Performance, Growth Rate, Mortality rate and Microbial Population of broile Chickens

This study was conducted to evaluate the effects of garlic and thyme’s medicinal plants essential oils blend as a feed additive following feed restriction on growth performance, relative growth rate and ileal microbial population of broiler chickens. This study was conducted using 336 one-day old chickens (Ross 308) as a factorial experiment (2×3) in a completely randomized design in six treatments with four replications and 14 birds per each replicate . The factors included two levels of feed restriction (without feed restriction and %10 feed restrictions) and three types of growth promoter additives (none-additive, blend of essential oils and antibiotic). The results showed that the body weight in 18 days of age was significantly affected by feed restriction (P <0.05). Feed restriction, feed additive and interaction between them did not affect the performance parameters. The addition of EO resulted in significant reduction in mortality rate (P <0.05). Feed costs for one kg of body weight were not affected by experimental treatments. Under the feed restriction, the population of E. coli and the total aerobic bacteria in ileum significantly reduced at 18 days of age (P <0.05). At 42 days of age, the addition of EO resulted in a significant reduction in E.coli, total aerobic bacteria count and increasing Lactobacillus counts (P <0.05). As a general conclusion, use of EO in feeding chicks faced with feed restriction could significantly increase the compensatory growth and might reduce the mortality and improve the ileal microbial population as well.