According to alternative practitioners, the more common causes of mucus in stool includes bacterial overgrowth and food allergies and sensitivities. They are often easily corrected with dietary changes and supplements. With bacterial overgrowth, bloating and gas usually worsen after eating any sugar, whether it's white sugar, bread, pasta, rye, rice, or milk (which contains the sugar lactose). In contrast, people with food allergies and sensitivities react to specific foods.
It is common for IBSers and IBDers to have excess mucus, excess mucus would definitely be the case when you go to have a BM and only mucus comes out and not stool.
Taking a good probiotic along with a fibre supplement both daily and indefinitely can aid with excess mucus as well as other IBS symptoms.
My bum is broken....there's a big crack down the middle of it! LOL :)