SHRI SHIVAJI SCIENCE COLLEGE, AMRAVATI
DBT STAR COLLEGE PROJECT ACTIVITY
ACTIVITY REPORT
Study of Fungal Infection in Freshwater Fishes
Activity Dates: 20/09/2024
Type of Activity: Minor Research Project
Organizing Department: Department of Zoology
Program Coordinators: Dr.Gajanan A.Wagh
Head of the Department: Dr.J.D.Dhote
External Collaborator (if any): No
Objectives:
- 1. Hands on Training of Sterilization & culture media preparation
- 2. To learn the fungus inoculation process
- 3. To identify the fishes affected with fungal infection morphologically.
- 4. To develop a culture of fungus of affected fish
- 5. To identify the grown fungus by preparing slides.
No of Beneficieries: 40
Classes Involved: Students of B.Sc.III (MEB)
Venue of the Activity: Department of Zoology
Activity Report:
SHRI SHIVAJI SCIENCE COLLEGE, AMRAVATI
Department of Zoology
Minor Research Project
UNDER DBT PROJECT SCHEME
Students Activity
Title of the Project
Study of Fungal Infection in Freshwater Fishes
Project Report
Target Group: B.Sc.III (MEB) students
No. of beneficiaries: 39 students of B.Sc.III (MEB)
Aims & objectives:
1. Hands on Training of Sterilization & culture media preparation
2. To learn the fungus inoculation process
3. To identify the fishes affected with fungal infection morphologically.
4. To develop a culture of fungus of affected fish.
5. To identify the grown fungus by preparing slides.
Introduction:
Freshwater fish has dominated the aquaculture production sector worldwide as global fish production from cultured fisheries. However, some unwarranted changes in the environment and emergent diseases adversely affect the fisheries industry. An estimated loss due to diseases in the aquaculture sector has exceeded US$ 6.5 billion annually in recent years (Magray, A. R., et.al.2021). Fungal diseases of fish are considered to be a major problem for both fisheries and aquaculture. Fish are continuously exposed to the microorganisms present in water and sediments (Iqbal, Z., et.al.2012). Fungi, which cause fungal disease, are present in salt or freshwater. In most cases, fungi serve a valuable ecological function by processing dead organic debris. However, fungi can become a problem if fish are stressed by poor nutrition, pressure of population, and over-exploitation of fishes. Fungal infections of freshwater fish are common, distributed worldwide, and associated with immune suppression. Fungal diseases are easily recognized by relatively superficial, colonies of fluffy growth on the skin and gill of fishes (Siddique, M. A. B., et.al.2009). Fungal infection is also known as mycoses. Fungi, however, can cause disease under a variety of other circumstances. Some may be more aggressive and play a more primary role. Fungi can be external or internal and systemic. Fungi can cause problems during reproduction, for example, by infecting fertilized eggs in spawns. Certain species of fungi can grow in poorly stored feeds and produce mycotoxins. Over the past decade, especially in wild fish populations, fungal agents have received considerable attention worldwide (Yanong, R. P.,2003).
Material and methods:
Fish affected by fungus have been brought to the departmental laboratory. The targeted fish samples for the experiment were from the Tapi, Sipna, and Gadga rivers of the Melghat region, Amravati.
Methodology:
Six fishes Catla, Rohu, Pangasius, Eel, Channa punctatus, Channa striata were collected from a pet fish shop in Dharni Fish Market, Melghat region, Amravati. The fish were transported immediately to the laboratory in sterile polyethylene bags in aerated water. The fish were kept separate in glass aquariums with a continuous air supply at ambient temperature. The fish body was divided into two parts; Anterior part (head, eyes, and gills) and posterior part (all fins and rest of the body) to note the infection site. For culturing of fungal specimens, potato dextrose agar (PDA) was prepared and streptomycin sulfate was supplemented to each preparation of media to avoid bacterial contamination. The body surfaces of all the fishes under study were disinfected by dipping each fish in 1% formaldehyde for 1 to 5 minutes followed by 70% alcohol and finally in sterile water in which it was thoroughly rinsed. The fungal isolates were collected from infected organs of fish with sterile needles and inoculated on potato dextrose (M096-India) agars. The agar plates were incubated at 28-30°C and fungal growth was observed after 4-7 days. The fungal colonies of various colors were observed in the agar plates. For microscopic examination, slides were prepared from each colony and stained with 0.05% Trypan blue in lactophenol. The slides were observed under the compound microscope. The fungi were identified with the help of available fungal identification keys and literature.
Results:
In total five species of fungus have been identified from the different organs of six samples. Samples were taken from the gills of Catla and the dorsal fins of Channa striata from the Tapi river. Further samples were taken from the skin of Pangasius and the gills of Channa punctatus from the Gadga river. The collection of samples from the skin of both Rohu and Eel has been done from the Sapan river of Melghat Tiger Reserve. Different types of fungi have been identified like Aspergillus niger, Candida albicans, Cunninhamell, Fusarium culmorum, Aspergillus falvus from the samples collected. Aspergillus falvus has been found commonly and Cunninhamell was rare. All the organs considered were infected with fungi and its signs were seen on the body morphologically.
Sr.No. River Fish Organ Sampled Fungal growth Fungus Identification Color
1. Tapi Catla catla Gills Yes Aspergillusniger, Candida albicans Green, White
2. Tapi Channa striata Dorsal Fins Yes Cunninhamell Off white
3. Gadga Pangasius Skin Yes Fusarium culmorum Brown
4. Gadga C.Punctatus Gills Yes Aspergillus falvus Parrot green
5. Sapan Rohu Skin Yes Candida albicans, White
6. Sapan Eel Skin Yes Aspergillus falvus Parrot green
Discussion:
Fungi were isolated from different body parts of the fish. Isolated fungi were identified as Aspergillus species, Candida species, Fusarium species The most prevalent fungal isolates were Aspergillus spp. followed by the other. The gills with infection were the most affected area. The dorsal fin showed the lowest infection. Infection on vital organs like gills and eyes seems to be more serious and fatal. Gill infection results in damage to secondary lamellae and may cause respiratory stress and impairment to fish, and eyes may become blind due to the presence of fungal hyphae.
Aspergillomycosis has been principally described in African fish, especially the tilapia Oreochromis species. Several Aspergillus species such as A. flavus, A. japonicus, and A. terreus are involved in this infection. These species presumably cause infection by entering the fish through contaminated feed (Iqbal, Z., Sheikh, et.al.2012). The anterior part of the fish had significantly higher infection than the posterior part of the fish. This is in contrast to those who reported that the posterior part of the fish had significantly higher infection than the anterior part (Iqbal, Z., Najam, et.al.2014).
Conclusion:
This study aimed to investigate the occurrence of fungal infections in various fish species collected from different rivers in the Melghat region. The results revealed a significant presence of fungus with Aspergillus flavus being the most commonly identified species. Additionally, Aspergillus niger was also detected in several fish samples. The study highlights the importance of monitoring fungal infections in fish populations to safeguard their health and prevent economic losses in aquaculture. Further research is necessary to understand the factors contributing to the prevalence of these fungal pathogens and to develop effective prevention and treatment strategies.
Significant Outcomes:
1. Students learned the culture media preparation process
2. Known the fungus inoculation techniques
3. studied the fungal infection to the fishes morphologically.
4. Known dominant fungal infection to the fishes especially of Aspergillus flavus.
Outcomes:
- Students learned the culture media preparation process
- Known the fungus inoculation techniques
- Studied the fungal infection to the fishes morphologically.
- Known dominant fungal infection to the fishes especially of Aspergillus flavus.
- Known the basic fungus identification process
Photos:
 Sterilized material setup for inoculation |  Demonstration of use of laminar airflow |
 Demonstration of inoculation process |  Expert giving hands on training to participants |
 Participants observing the media preparation process |  Fungus grown on culture media |
Attendance Sheet:
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