Pre‐ and Post‐Hatch Effects of Eucalyptol Supplements to Water‐Based Humidifiers in Broilers’ Incubators

Direct abiotic environmental factors may influence embryonic development, chick quality and adult pheno-type. Supplementing various levels of 1, 8-cineol (eucalyptol) to water as humidity source in broiler’s incu-bator and investigating its pre- and post-hatch effects to determine the appropriate application protocol were the aims of this study. Four levels (0, 0.2, 0.4, 0.6%) of pure eucalyptol with 3 replicates were used on 1440 Ross 308 broiler chicks. During incubation, moisture loss on 18th day of incubation, hatchability, and weights of hatched chicks were measured. Post-hatch, various performance factors and carcass traits were determined through 42 d rearing period. Eucalyptol at 0.2% resulted in the greatest moisture loss at 18 d of incubation (12.8%) in addition to the highest hatchability (91.8%) and the highest hatched weight (45.9 g) (P<0.05). The same treatment (0.2% eucalyptol) significantly improved average daily gain (ADG), feed conversion ratio (FCR), and the percentage of breast, thigh and back-neck (P<0.05). The positive effects of 0.2% eucalyptol on pre- and post-hatch traits indicate that this new protocol of incubation may be of benefit to the world broiler industry. The potential links between eucalyptol as a source of humidity for incubation and epigenetic modification and/or other modification mechanisms require further investigation.