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.
Less often, having anal sex or putting things into your anus can overstretch the skin and cause a fissure. Too much pressure, tight anal sphincter muscles, and poor blood supply to your anus may lead to their development and poor healing. Anal fissures don't usually give way to more serious problems. They donât cause cancer. But they can be very uncomfortable. To help these fissures heal and keep them from coming back: 1  Eat a healthy diet that has plenty of fiber. 2  Stay well-hydrated.