Research progress on gut health of farmers teleost fish: a viewpoint concerning the intestinal mucosal barrier and the impact of its damage

The intestinal mucosal barrier plays a critical role in the maintenance of host health. In farmed teleost fish, the intestinal epithelium is challenged by a number of factors, leading to damage of the intestinal mucosal barrier. The pathogenesis of intestinal mucosal barrier damage in most farmed teleost fish has been associated with cell death, mainly including apoptosis, pyroptosis, necroptosis as well as secondary injury by cell lysis. However, the mechanisms behind intestinal mucosal barrier damage are not well studied. Here we summarized the factors causing damage of intestinal mucosal barrier in fish. Further we discussed the intracellular and interstitial signaling cascades, with special emphasis on cell death that potentially accelerates the progression of intestinal injury. Deeper understanding of the mechanisms of intestinal mucosal barrier damage may facilitate the development of potential intervention strategies for intestinal diseases in farmed teleost fish.