The scientists compared slow freezing and vitrification to preserve cat embryos. They wanted to see how the freezing methods affected embryo development and studied the behavior of fats during cooling. They used different liquid mixtures to freeze the embryos and then observed how well they developed after being frozen and thawed. They found that both freezing methods worked similarly, with a good number of embryos reaching important development stages. The number of cells in the embryos and the presence of broken cell parts were similar in all groups. They also discovered that cat embryos have a low temperature for a crucial fat phase change (–2.2°C), suggesting that slow freezing could be a good choice for storing cat embryos. Overall, the study shows that both slow freezing and vitrification can be used successfully for preserving cat embryos.