Effect of the essential oil of Croton nepetifolius Baill on cervical penetration in crossbred Dorper and Santa Inês ewes

ABSTRACT In order to evaluate the use of the essential oil of Croton nepetifolius Baill (EOCn) on cervical penetration in crossbred ewes, 40 ewes were randomly allocated into four groups (n= 10): CONTROL, MISOPROSTOL, EOCn50 and EOCn100 (50 e 100µg of the EOCn, respectively). After estrus synchronization, using CIDR and eCG (200IU), depth of cervical penetration was measured using artificial insemination gun for bovine species which was graduated and used from 0 to 72h after CIDR removal. Results were expressed as mean ± standard error mean, submitted to ANOVA and Tukey test while data in percentage were submitted to Fisher or Chi-Square test. No significant difference (P> 0.05) was observed at grade of cervical penetration. Concerning trespassing time, MISOPROTOL and EOCn100 groups presented a lower trespassing time at 60h (1.7±0.6 and 1.5±0.6min, respectively) than CONTROL group (4.1±0.6min), which did not differ significantly from EOCn50 (2.3±0.6min) group. Therefore, the essential oil of Croton nepetifolius Baill can be used to shorten the cervical penetration time in estrus synchronized ewes.