Respiratory System:
* Lungs: These are the primary organs of respiration. In the fetal pig, the lungs are relatively small and collapsed, as they don't function until birth.
* Trachea: The windpipe, connecting the pharynx to the lungs.
* Bronchi: The two branches of the trachea that lead into the lungs.
Circulatory System:
* Heart: The central organ of the circulatory system. In the fetal pig, the heart is relatively large compared to the adult pig due to the presence of the foramen ovale and ductus arteriosus, which are fetal circulatory shunts.
* Aorta: The main artery carrying oxygenated blood from the heart.
* Vena cava: The major vein returning deoxygenated blood to the heart.
Other:
* Thymus gland: This gland is located in the upper chest and plays a crucial role in the development of the immune system.
* Esophagus: The tube that connects the pharynx to the stomach.
* Diaphragm: The muscular sheet that separates the thoracic cavity from the abdominal cavity.
Important Note:
* The fetal pig's thoracic cavity is smaller and the organs less developed compared to an adult pig.
* During dissection, carefully observe the connections between these organs and the surrounding structures.
Remember, the organs and their relative sizes can vary slightly in individual fetal pigs. It's crucial to refer to a detailed anatomical atlas or guide for accurate identification.