Anatomical and morphometrical study of middle ear ossicles in 2 to 3-month-old Makouei sheep fetuses

The middle ear ossicles are important due to transmission of sound to the inner ear leading to sound understanding. The aim of present study was to determine the anatomical and morphometrical aspects of middle ear ossicles in Makouei sheep fetuses. For this experimental study, eight sheep fetuses at the age of 2 to 3 months were provided from public slaughterhouse; their middle ear ossicles were removed from tympanic cavity subsequently and assessed anatomically using stereomicroscope. For statistical analysis, one-way ANOVA and Tukey’s post-hoc test were used. The results showed that rostral process of malleus doesn’t exist, but an osseous lamina extending to the tympanic bulla and tympanic ring is located in this place. Moreover, lenticular bone and muscular process of stapes weren’t found. These findings were similar to the other animal’s ossicles anatomical features, but there were also some differences that can be useful for study of these ossicles developmental evolution.