Inclusion of Hot Water Extract of Laurus nobilis leaf in Koi carp Diet and its Impact on Growth Performance and Skin Mucosal Immunity

Abstract

Koi carps are beautiful ornamental fish that are favoured for their
stunning colours and beautiful appearance. In day-to-day life, ornamental
fish culture is a much-preferred hobby by people, not only due to their
attractive nature but also due to their stress-relieving properties. In this
view, their growth enhancement and immune performance is of great
concern. Phytobiotics and their usage in aquaculture sector has gained
attention due to their versatile role as an appetite stimulator, growth
enhancer and immune modulator. In this aspect, in the present study
L.nobilis leaves was subjected to evaluation to explore their beneficial
effects. In addition, they have sufficient, amount of Vitamin A, Vitamin
B6, Iron, Potassium and calcium that may play a vital role in improving
the immune status of fish. Further, they have certain enzymes that help in
the digestion of food. In the present study, koi carp fed on the B2 diet
registered a high production of 4.955 ± 0.06g compared to a low
production of 2.289 ± 0.02g noticed in koi fed on the control diet. The
skin mucosal immune parameters, such as total immunoglobulin,
lysozyme activity, bactericidal activity and alkaline phosphatase, were
high in fish received hot water extract (HWE) of L.nobilis leaf coated diet
compared to control diet fed fish.