Effect of etofenamate on midline closure defect in early chicken embryos: an experimental study

The aim of this study is to investigate the effect of etofenamate, a nonsteroidal anti-inflammatory drug, on the development of midline closure defects in early chick embryos. The study was conducted at the Animal Laboratory of the Department of Animal Science, Faculty of Agriculture, Kahramanmaraş Sütçü İmam University. A total of 80 fertilized, pathogen-free, day-zero Broiler chicken eggs were used. The eggs were incubated for 24 h at 37.8 ± 0.2 °C with 65-75% humidity in an incubator with an automatic turning system. Subsequently, a 0.3 cm window was made in the eggs, and the eggs were randomly divided into four main groups and administered different doses of etofenamate (1, 2, 4 mg/day). On the 10th day of incubation, embryos were evaluated macroscopically, and those showing developmental delay or being unfertilized were excluded. Histological samples were taken from the brain and spinal cord regions of developed embryos to assess neural tube formation. In the control group, neural tube closure occurred in 95% of the embryos, while one embryo (5%) in the low-dose etofenamate group exhibited a neural tube defect. No neural tube defects were observed in the medium and high-dose groups; however, both groups showed a 25% rate of early embryonic death. The results indicate that etofenamate may negatively affect neural tube development at low doses, with the effect varying depending on the dose, and that higher doses increase the risk of embryonic death.