title: Evaluation of chitinolytic activities and membrane integrity in gut tissues of Arctic charr (Salvelinus alpinus) fed fish meal and zygomycete biomass.
abstract: Chitinolytic activity, nutrient uptake and intestinal barrier functions were investigated in gut tissues of Arctic charr (Salvelinus alpinus) fed iso-nitrogenous diets based on fish meal, with or without inclusion of zygomycetes (Rhizopus oryzae). We found that gut tissue of Arctic charr had significant chitinase activity, of both endo- and exo-chitinase iso-forms. Moreover, the distribution pattern along the GI tract of Arctic charr differed between endo-chitinase and exo-chitinase. The endo-chitinase activity in stomach tissue and in the distal intestine was several hundred-fold higher than the exo-chitinase activity in stomach tissue. The greatest exo-chitinase activity was found in the distal intestine. The zygomycete-based diet resulted in higher chitinolytic activity in gut tissue compared to the fish meal-based diet. Disturbed intestinal integrity and increased uptake rate of the amino acid lysine were observed in the distal, but not proximal, intestine of fish fed the zygomycete-based feed.
authors.affiliation: Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, P.O. Box 7024, S-75007 Uppsala, Sweden.
authors.forename: Rani
authors.initials: R
authors.lastname: Abro
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, P.O. Box 463, S-40530 Gothenburg, Sweden.
authors.forename: Kristina
authors.initials: K
authors.lastname: Sundell
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, P.O. Box 463, S-40530 Gothenburg, Sweden.
authors.forename: Erik
authors.initials: E
authors.lastname: Sandblom
authors.affiliation: Department of Biological and Environmental Sciences, University of Gothenburg, P.O. Box 463, S-40530 Gothenburg, Sweden.
authors.forename: Henrik
authors.initials: H
authors.lastname: Sundh
authors.affiliation: Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, S-90 83 Umeå, Sweden.
authors.forename: Eva
authors.initials: E
authors.lastname: Brännäs
authors.affiliation: Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, P.O. Box 7024, S-75007 Uppsala, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Kiessling
authors.affiliation: Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, P.O. Box 7024, S-75007 Uppsala, Sweden.
authors.forename: Jan Erik
authors.initials: JE
authors.lastname: Lindberg
authors.affiliation: Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, P.O. Box 7024, S-75007 Uppsala, Sweden. Electronic address: Torbjorn.Lundh@slu.se.
authors.forename: Torbjörn
authors.initials: T
authors.lastname: Lundh
mesh_terms: D000821:Animal Feed; D000818:Animals; D018533:Biomass; D002462:Cell Membrane / Q000378:metabolism; D002686:Chitin / Q000378:metabolism*; D002688:Chitinases / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000648:ultrastructure; D012233:Rhizopus; D012487:Salmonidae / Q000378:metabolism*
chemical_list: D002686:Chitin; D002688:Chitinases
keywords: Amino acid absorption; Chitin; Intestinal barrier functions; Plasma cortisol; Zygomycetes