The ventral mesentery forms the lesser omentum, and is attached to the developing liver. Malignancy is characterized by local invasion and metastases, usually to the liver, omentum and peritoneum. These are found most often on the peritoneum, in the liver, and in the omentum. Usually this involves leaving parts of splenic parenchyma in pouches of omentum. Focal adhesions frequently tether the greater omentum to the cephalad aspect of the transverse mesocolon. The greater omentum is the larger of the two peritoneal folds. Other sites in cattle include the spleen, muscle, gastrointestinal tract, omentum, and uterus. The Fallopian tubes (salpingectomy), uterus (hysterectomy), and the omentum (omentectomy) may also be removed. Metastasis is most commonly to the liver, omentum, lungs, or brain. The dorsal mesogastrium develops into the greater omentum. The phrenicosplenic ligament is part of the greater omentum. The other is the lesser omentum that extends between the stomach and the liver. The lesser sac is formed during embryogenesis from an infolding of the greater omentum. In radiology, omental cake is sign indicative of an abnormally thickened greater omentum. A piece of omentum is used to cover the perforation.