Ramos colaterais viscerais da artéria aorta abdominal em Myocastor coypus (nutria) The collateral visceral branches of the abdominal aorta in Myocastor coypus (nutria)

Nutria is a native rodent from the south of South America commercially explored for meat and fur. In this paper the collateral visceral branches of the abdominal aorta were systematized. Thirty nutrias were used, 15 males and 15 females, with the aortic-abdominal arterial system injected with latex 603. The abdominal aorta emitted, ventrally, as visceral collateral branch the celiac artery, which trifurcated in left gastric, hepatic and lienal arteries. The celiac artery branches promoted t he irrigation of the stomach, duodenum, liver, pancreas and spleen. Following, the abdominal aorta emitted the cranial mesenteric artery, of bigger caliber than the celiac artery, caudally juxtaposed. The cranial mesenteric artery emitted branches to vascul arizing the final part of the duodenum, right lobe of the pancreas, jejunum, ileum, cecum, large colon and small colon. The abdominal aorta laterally emitted the right and left renal arteries. The adrenal arteries were direct collateral branches of the renal ar teries and/or the frenic abdominal artery. The caudal mesenteric artery was emitted from the ventral surface of the abdominal aorta, next to its bifurcation into the common iliac arteries. The caudal mesenteric artery launched branches to the small colon and cranial portion of the rectum. The direct visceral collateral branches of the abdominal aorta were: celiac artery, cranial mesenteric artery, renal arteries and caudal mesenteric artery. The indirect visceral branches were: adrenal arteries and umbil ical artery. The external iliac artery emitted the umbilical artery, which irrigated the bladder and continued as a big uterine artery on females, irrigating all the uterus including the ovaries, and on males, the testicular artery, which irrigated the testis.