Temporal appearance of embryonic compartments and their sexual dimorphism in chicken

1. Building on established understandings regarding hormonal and metabolic-driven processes of avian embryo's growth and development, this paper proposes a novel method, focusing on sex-related dimorphism. Such processes involve crucial activities, <i>e.g</i>. nutrition delivery, gas exchange and waste disposal. These are influenced by interactions among various structures within embryonic compartments, whose sequential patterns between males and females have been proven different.2. The embryonic compartments, having undergone physiological changes during d 8-12, were acquired from candled images. Their temporal appearance model was developed from a non-linear classifier. It was hypothesised that if there is any distinctive pattern associated with the embryonic compartments between embryo sexes, then the classifier can be trained to recognise the dimorphism.3. The results revealed that the proposed method could separate sexes <i>in ovo</i> with accuracy, recall, precision and balance accuracy of 94.71, 93.47, 95.92 and 94.72%, respectively. Error analyses found 4.82% false discovery and 9.78% false omission rates. The method was expected to enhance farming resource management and leads to better animal welfare.