title: Effect of dietary chitosan on growth performance, hematological parameters, intestinal histology and stress resistance of Caspian kutum (Rutilus frisii kutum Kamenskii, 1901) fingerlings.
abstract: This study was conducted to investigate the effects of dietary chitosan on growth performance, hematological parameters, intestinal histology, stress resistance and body composition in the Caspian kutum (Rutilus frisii kutum, Kamenskii, 1901) fingerlings. Fish (1.7 ± 0.15 g) were fed diets containing chitosan at different levels (0, 0.25, 0.5, 1 and 2 g kg(-1) diet) for a period of 60 days. Results showed that the feed conversion ratio significantly decreased in fish fed diet containing 1 g kg(-1) of chitosan compared to the other groups (P < 0.05), but there were no significant differences between treatments in terms of specific growth rate and condition factor (P > 0.05). Leukocyte increased in fish fed diet containing 2 g kg(-1) of chitosan compared to the other groups (P < 0.05). Lymphocytes, eosinophils and neutrophils did not significantly change among dietary treatments (P > 0.05). Also, the chitosan supplementation did not affect the whole-fish body composition (P > 0.05). Light microscopy demonstrated that the intestinal villus length increased in fish fed diet containing 1 g kg(-1) of chitosan compared to control group (P < 0.05). While 11 and 13 ‰ salinity and 30 °C thermal stress had no effect, 1 g kg(-1) of chitosan (P < 0.05) showed highest survival rate (70 %) in 34 °C thermal stress. The results showed that chitosan in the diet of the Caspian kutum fingerlings could improve feed conversion ratio, the nonspecific defense mechanisms and resistance to some of the environmental stresses.
authors.affiliation: Department of Fisheries, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resource, Gorgan, Iran. Masume.kamali91@yahoo.com.
authors.forename: Masume
authors.initials: M
authors.lastname: Kamali Najafabad
authors.affiliation: Department of Fisheries, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resource, Gorgan, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Imanpoor
authors.affiliation: Department of Fishery, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resource, Gorgan, Iran.
authors.forename: Vahid
authors.initials: V
authors.lastname: Taghizadeh
authors.affiliation: Department of Fishery, Faculty of Fisheries and Environmental Sciences, Gorgan University of Agricultural Sciences and Natural Resource, Gorgan, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Alishahi
mesh_terms: D000818:Animals; D001835:Body Weight / Q000187:drug effects; D048271:Chitosan / Q000494:pharmacology*; D003530:Cyprinidae / Q000254:growth & development*; D019587:Dietary Supplements; D006403:Hematologic Tests; D006358:Hot Temperature; D007422:Intestines / Q000033:anatomy & histology / Q000187:drug effects; D054712:Salinity; D013312:Stress, Physiological / Q000187:drug effects
chemical_list: D048271:Chitosan
keywords: Blood parameters; Chitosan; Growth; Intestinal histology; Rutilus frisii kutum; Stress