Structure topography and innervation of the abdominal wall muscles of a raccoon dog

The muscles of the abdominal wall of the Raccoon dog, as in most mammals, are represented by three broad muscles - the external and internal oblique and transverse abdominal muscles and one long muscle, the straight abdominal. The external oblique abdominal muscle is represented by a broad muscle layer located on the lateral and ventral surfaces of the abdominal wall. It originates from the edges. Below it is the internal oblique abdominal muscle, consisting of the costal, abdominal and inguinal parts, bundles of muscle fibers that originate from the ribs, sternospinal fascia and inguinal ligament, respectively. Under the internal oblique abdominal muscle is the transverse abdominal muscle, which starts from the ribs and transverse processes of the lumbar vertebrae. Ventrally, all the broad abdominal muscles pass into broad aponeuroses, which, connecting with similar aponeuroses of the opposite side, form a straight line of the abdomen. Also, aponeuroses are involved in the formation of the vagina of the rectus abdominis muscle. The rectus abdominis muscle runs through the entire body of the raccoon dog, along the ventral surface of the chest and abdominal walls. It starts from the first rib and ends at the pubic bones of the pelvis. In the area of the abdominal wall, the rectus abdominis muscle passes through the vaginal cavity formed by aponeuroses of the large abdominal muscles. All the muscles of the abdominal wall are involved in the formation of the inguinal canal, through which the abdominal cavity communicates with the scrotal cavity. Innervation of all abdominal wall muscles is carried out by the ventral branches of the thoracic and lumbar spinal nerves: intercostal, costal-abdominal, ileo-submandibular and ileo-inguinal. Due to the increase in the lumbar bone segments to seven, the Raccoon dog has two ileo-submandibular nerves - cranial and caudal.