[Experimental malformations of the body wall in the chick embryo]

The rapidly growing possibilities of prenatal diagnosis and intrauterine manipulation of the malformed fetus have created the need for animal experimental models as simple and easy to handle as possible. We report on our experience with the induction of body wall defects in the chick embryo. Laparoschisis was produced by evisceration of the bowel through the umbilical stalk and its exposition to the allantoic fluid at the 14th day of incubation. Exomphalos, Cantrell's Pentalogy and Spina Bifida were induced by sterile aspiration of 5 ml of egg albumen at the 24th hour of incubation. All embryos were recovered and studied at the 19th day of incubation. The results can be summarized as follows: ninety-four (51%) of the 184 embryos operated for bowel exteriorization survived and 42 (45%) had intestinal lesions identical to those found in human laparoschisis. Two-hundred ans seventy (45%) of the 602 embryos treated by albumen extraction survived and 197 (73%) had no visible malformations, whereas either exomphalos or Cantrell's pentalogy were found in 37 (14%) and spina bifida was observed in the remaining 36 (13%). All lesions were strikingly similar to the human ones. These models could facilitate research on the above-mentioned malformations without the major difficulties and expenses inherent to fetal research in mammals. The chick embryo, for many decades a favorite model for embryologists, is a tool for fetal research as well and opens some perspectives in this field even for relatively modest laboratories.