Identification and control of fungal organism affecting artificially incubated eggs of Clarias gariepinus

Abstract

One of the challenges confronting fish farmers is the problem of maintaining a high survival of fish from larvae/fry to adult/table-sized stage. Fungi are problem in hatchery operations preventing successful hatching of fish eggs. This paper reports finding of a study carried out to identify and control fungal organisms affecting artificially incubated eggs of Clarias gariepinus. Infected eggs of Clarias gariepinus were disinfected in malachite green, saline and acalypha solutions at various concentrations for a period of one hour. Observations were made for fungal growth inhibition, using Agar–egg transfer technique at 25⁰C at 24 hourly intervals for five days. Findings revealed that Saprolegnia majorly affects artificially incubated eggs of Clarias gariepinus. Acalypha solution has the same effect as malachite green and saline solution inhibiting the growth of fungi. The boiled Acalypha solution was more potent than the unboiled due to application of heat which hinders the activities of pathogen. Boiled Acalypha solution at different concentrations can be used as disinfectant in controlling fungal infection in fish. Fish farmers should be educated and encouraged in carrying out good management practices in their farms.

Keywords: Clarias gariepinus; Fungal Organism; Identification; Control; Incubated Eggs