Anthelmintic efficacy of Lippia alba essential oil against gastrointestinal nematodes in goats

This study aimed to evaluate the anthelmintic efficacy of Lippia alba essential oil against gastrointestinal nematodes in goats, identify the helminth genera present, and perform a chemical characterization of the tested oil. Fecal samples were collected and quantified using the McMaster technique; samples with counts above 200 eggs per gram (EPG) were included in the experiment. The pooled positive sample showed an EPG of 2800. Quantitative coproculture was conducted with a negative control group (distilled water) and L. alba essential oil at concentrations of 10 mg/mL, 25 mg/mL, 50 mg/mL, and 100 mg/mL, maintained at room temperature for 10 days. Subsequently, larvae were recovered, identified, and quantified. Treatment efficacy was assessed using the larval reduction formula. Concentrations of 25 mg/mL, 50 mg/mL, and 100 mg/mL were effective, achieving larval reductions of 79.5%, 87.8%, and 89.8%, respectively. The genera identified included Haemonchus sp. (56.8%), Trichostrongylus sp. (42.9%), and Oesophagostomum sp. (0.3%). Chemical composition of the oil was analyzed using gas chromatography-mass spectrometry with an advanced electron ionization source. Twenty-five compounds were identified, with E-citral (23.76%), Z-citral (20.46%), carvone (10.92%), and limonene (6.40%) being the most abundant. All tested concentrations of L. alba essential oil, except 10 mg/mL (29.7%), demonstrated anthelmintic potential by significantly reducing gastrointestinal nematode larvae in goats.