Chicken embryo as an experimental model for the study of gastroschisis.

PURPOSE To reproduce the experimental model of gastroschisis in chicken embryos and to prove that the histopathological changes that occur in this model can be compared to those in human gastroschisis. METHODS A total of 278 Leghorn hen (Gallus domesticus) eggs were used. The embryos were divided into three groups: the gastroschisis group, in which the umbilical cord was opened through an orifice made in the eggshell, and the intestinal loops were exposed to a mixture of amniotic liquid and allantoid; the mixture group, in which the amniotic fluid and allantoid were simply mixed without manipulating the umbilical stump and without exposing intestinal loops; and the control group which consisted of normal embryos in which no procedure was performed. The procedures were performed on the 13th day of embryo development and the study ended on the 19th day, when the intestinal loops of the embryos were removed and sent for conventional histological study and digital morphometric analysis. RESULTS At the end of the experiment, 23 live embryos were obtained in the gastroschisis group (11.1% survival), and 18 of these presented exposed intestinal loops (8.7% success). The embryos of the gastroschisis group weighed less than those of the other two groups. The gastroschisis group also developed intestinal changes consisting of the thickening of the intestinal wall, inflammatory infiltration of the serosa and mucosa, ischemic changes in the intestinal wall and formation of a fibrin layer over the loops. These findings are characteristic of human gastroschisis and were not observed in the two other groups studied. CONCLUSION The experimental model in chicken embryos proved able to reproduce the intestinal changes of human gastroschisis.