Ethanol effect on the chick embryo ossification: a macroscopic and microscopic study

This study attempts to analyze anomalies in avian embryos induced macroscopically and microscopically when exposed to ethanol (EtOH) during the first stages of development. Fertilized chicken eggs were employed in this study. The eggs were incubated at 37.8 degrees C. Some of the eggs were treated on day 0 with EtOH (20%, 40% and 60%) by instillation in the air sac. The control group was instilled with 0.1 ml of NaCl at 0.9%. Other eggs were treated on the 4th post-incubation day, employing the same methodology. The embryos in both groups were removed from the eggs on the 11th incubation day and examined using a dissecting binocular microscope. After macroscopic analysis, the samples obtained were fixed in 10% formol, photographed and processed according to common histological techniques and the Picrosirius method. Embryos treated with EtOH demonstrated a significant weight decrease. Microscopic analysis by means of the Picrosirius method revealed that the intra-membranous ossification process presents less development, and therefore there was less type I collagen in trabecular bone in the embryos post-exposure to EtOH with respect to the control.