Investigation of the effects of diet supplemented with chitosan as an immune stimulant on some skin mucus and serum immune factors in juvenile Beluga (Huso huso)

Abstract

Introduction: The effects of dietary supplemented with chitosan was investigated on
some growth indices, mucus immunity and blood serum in juvenile Beluga (Huso huso).
Materials & Methods: In this study, 240 fish (with an average weight of 60±0.12 g) after
two weeks adaptation to experimental conditions, were divided into 4 groups in 3
replicates and then were fed with different levels of chitosan; 0 (control), 5, 10 and 15
g/kg of diet for 8 weeks. At the end of the experiment, Biometrics were performed to
determine the performance of growth indices. Also, sampling was done randomly to
measure the desired indicators.
Results: The results showed that the highest final weight and final length, weight gain
percentage, specific growth rate and lowest feed conversion ratio were present in the diet
fed with diet containing 10 g of chitosan per kg of feed, which was significantly different
from the control group and other treatments. (P<0.05). The highest activity of mucosal
alkaline phosphatase and total protein was observed in the treatments fed with 15 and 10
g of chitosan, respectively, which were significantly different from the control group
(P<0.05). Also, the highest and lowest serum glucose and cortisol levels were related to
treatments fed with 15 and 10 g chitosan, respectively, which were significantly different
from the control group (P<0.05). The highest levels of albumin and total serum protein
were observed in the treatments fed with 10 g of chitosan, which were significantly
different from the control group (P<0.05). The lowest levels of alanine transaminase and
aspartate transaminase were observed in the treatments fed with 10 g of chitosan, which
was significantly different from the control group (P<0.05).
Conclusion: Due to the positive effects of chitosan as an immune stimulant, using this
substance in the amount of 10 grams per kilogram diet is recommended to promote the
health of beluga.