Antimicrobial effect of essential oil of Gallesia integrifolia (Phytolaccaceae) against bacteria and fungi on hatching eggshells and its influence on the production parameters of day-old chicks

Formaldehyde-based disinfectants, although widely used for hatching egg sanitation and pathogen control in poultry production, pose serious occupational health risks and face increasing consumer opposition, driving the search for eco-friendly alternatives. In this context, this study aimed to evaluate the potential of Gallesia integrifolia (Phytolaccaceae) fruit essential oil, known for its antibacterial and antifungal properties, as a natural biocide for eggshell disinfection. For the experiment, 192 eggs were selected from the nests of two breeder houses located in the northwestern region of the state of Paraná. The selected eggs were divided into control and treatment groups and identified using sequential numbers in groups of four eggs. Eggs in the control group were disinfected by spraying them with an aqueous solution containing 2% polysorbate at a rate of 2 mL per egg. Eggs in the treatment group were disinfected with an aqueous solution containing 2% polysorbate and G. integrifolia essential oil at a concentration of 0.44 mg mL-1. The efficacy of G. integrifolia essential oil was assessed by counting aerobic mesophiles and fungi on the eggshell surface. The eggs were incubated, and the production and quality parameters of the hatched chicks were evaluated using scores. The results showed that G. integrifolia fruit essential oil did not alter the evaluated production parameters. Aerobic mesophile counts, chick quality scores, the egg weight-to-chick weight ratio, total hatchability, and hatchability of fertile eggs did not differ significantly (p ³ 0.05) between treatments in either breeder house. However, fungal counts in the first breeder house differed significantly (p < 0.05) between the treatment and control groups.