Developmental abnormalities in chicken embryos after injection proteolysis inhibitors from Ascaris suum.

It has been found that trypsin and alpha-chymotrypsin inhibitors isolated from Ascaris suum act embryotoxically and teratogenically on White Leghorn chicken embryos. Mortality rate for the chicken embryos on day 15 of incubation was 45.0 +/- 3.5% after injection of trypsin inhibitor and 44.0 +/- 3.5% after adminstration alpha-chymotrypsin inhibitor. Gross examination of surviving embryos and their dissection revealed pathological changes (abdominal dropsy, umbilical hernia, subcutaneous oedema, hemoperitoneum, hemopericardium), symptoms indicating retardation in growth (lack of down, retarded ossification of long bones, decreased mean body weight) as well as malformations (schistocelia, micrognathia, cyclopia, crossed beak, cranial deformities) after injection of inhibitors from Ascaris. The highest incidence of embryos with pathological changes and malformations was found after administration of alpha-chymotrypsin inhibitor. The most commonly occurring abnormality was schistocelia (21.4 +/- 3.88%). Growth malformations were not found in the control groups. The trypsin and alpha-chymotrypsin inhibitors present in Ascaris homogenate have a significant disturbing effect on the development of the chicken embryo.