Marine stickleback populations live and breed strictly in the ocean. Sea-run stickleback fish are. anadromous, meaning that they are born in fresh water, spend most of their lives in the ocean, and. return to fresh water to breed. Freshwater stickleback fish live entirely in fresh water.
Among patients with Crohn's disease, 4% will have an anal fissure as the first manifestation of their Crohn's disease, and half of all patients with Crohn's disease eventually will develop an anal ulceration that may look like a fissure.
Anal fissures are caused by trauma to the anus and anal canal. The cause of the trauma usually is a bowel movement, and many people can remember the exact bowel movement during which their pain began. The fissure may be caused by a hard stool or repeated episodes of diarrhea.nal fissures are caused by trauma to the anus and anal canal. The cause of the trauma usually is a bowel movement, and many people can remember the exact bowel movement during which their pain began. The fissure may be caused by a hard stool or repeated episodes of diarrhea.