Dietary chitosan positively influences the immunity and reproductive performances of mature silver barb (Barbonymus gonionotus)

Abstract

This research was carried out to assess the effects of dietary chitosan on the immunity and reproductive performance of adult Barbonymus gonionotus. The fish (average weight 66.7 ± 0. 86 g) were randomly divided into four treatments: control (0.00 g/kg), CHT-1 (1.00 g/kg), CHT-2 (2.00 g/kg) and CHT-3 (3.00 g/kg) and were fed the appropriately formulated diets for 60 days. The results showed significant differences in the immunological parameters such as lymphocytes, neutrophils, monocytes, immunoglobulin (IgM), and lysozyme activity in the chitosan-fed fish compared to those in the control diet-fed fish. The reproductive hormones such as follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were significantly enhanced in chitosan fed fish compared to the control. Furthermore, the chitosan-treated diet significantly improved the reproductive performance of adult B. gonionotus compared to control fish. Qualitative histological studies showed that chitosan significantly improved egg morphology and showed mature and uniformly sized eggs compared to the control fish. Similarly, a quantitative histological investigation revealed that chitosan significantly increased oocyte area (µm2) and number of oocyte-3 compared to the control. In conclusion, our study found that dietary chitosan at optimal dose of 1.00 g chitosan/kg feed enhanced immunity, regulated reproductive hormone levels, and promoted reproductive performance and ovarian development in B. gonionotus.

Keywords

• Chitosan
• Immunological parameters
• Reproductive performances
• Morphology of ovum, mature Barbonymus gonionotus