» Conformation and Surface Anatomy
The cranial boundary of the accessible abdominal wall is easily determined by palpation of the last rib and costal arch. The caudal boundary is discovered from palpation of the ventral part (pecten ossis pubis) of the pelvic inlet between the thighs.
Although the wings of the ilia are prominent landmarks, they pertain to the back. The covering of thick muscles does not allow palpation of the lumbar transverse processes themselves, but the tips of the spinous processes provide a guide to the identification of individual vertebrae.The abdominal cavity is of course larger than these landmarks appear to indicate because the diaphragm bulges far into the rib cage at its cranial end. The organs in this intrathoracic part of the abdomen are protected by the ribs and are in part overlain by the caudal lobes of the lungs. The abdominal cavity is relatively less voluminous than in the large domestic species and has, by and large, the shape of a cone with a bulbous cranial base (Fig. 14.1). Its longitudinal axis, which is steepest in deep-chested breeds, inclines cranioventrally at an angle that varies considerably. Except in fat subjects and heavily pregnant or lactating bitches, the ventral abdominal wall rises from the sternum to the pecten in a straight or even slightly concave line. Dog fanciers use the expression "tucked-up" to describe animals with an especially shallow body depth at the loin. The skin fold that connects the flank with the stifle tends to obscure the shallowness of this part. Advancing pregnancy enlarges the abdomen in both depth and breadth and gives it a more cylindrical or even a barrel shape.
Superficial inguinal lymph nodes may be palpated in the groin, lateral to the bulbus glandis of the penis or in a comparable site in the bitch (Fig. 14.2B/6).