Assessing the cultured bacterial flora of Nematodes Panagrellus redivivus and Radopholus similis as live feed for larval fish

Deniz Devrim Tosun; Pelin Saliha Çiftçi Türetken; Remziye Eda Yardımcı

doi:10.3153/AR26001

EN

Assessing the cultured bacterial flora of Nematodes Panagrellus redivivus and Radopholus similis as live feed for larval fish

Abstract

Using live organisms as feed is essential for successful larval breeding in aquaculture, especially during early developmental stages when digestive capabilities are at their initial stages. While rotifers and Artemia are commonly used, alternative organisms, such as free-living nematodes, have gained interest due to their ease of culture, small size, and low production costs. It is well known that live feeds harbour dense microbial communities. Some of these may include opportunistic or pathogenic bacteria, which can pose risks to larval health. This study aimed to assess the cultured bacterial flora associated with two nematode species, Panagrellus redivivus (microworms) and Radopholus similis (bananaworms), which are commonly considered to be live feed alternatives in aquaculture. Both nematode species were cultured in an oatmeal-yeast-water medium under identical conditions. Total viable counts (TVC) were determined from disinfected nematode samples, and bacterial isolates were identified to the genus level through morphological, biochemical, and phenotypic assays, complemented by genus and limited species-level verification using the VITEK 2 Compact identification system. Both species primarily had Gram-negative bacteria (75%), with Aeromonas and Pseudomonas being the most common types found. Additional isolates included Enterobacter, Citrobacter, Proteus, Staphylococcus, and Vagococcus. The range of nematodes compares favourably to high-load cultures of traditional live feeds. Species-level characterisation suggested the presence of potential fish or human pathogens, including Klebsiella pneumoniae ssp pneumoniae, Serratia rubidaea and Enterococcus faecalis. The findings suggest that while nematodes offer a promising alternative to traditional live feeds, their associated bacterial communities include potential pathogens that require careful consideration. Further studies focusing on bacterial virulence, larval interaction, and microbial management strategies (such as light treatment) are essential to ensure the safe application of nematodes in larval rearing systems.

Keywords

Supporting Institution

This research was funded by the Scientific Research Projects Coordination Unit of Istanbul University, grant number 20359

Project Number

20359

Ethical Statement

This study did not involve experimental procedures on live vertebrate animals or human subjects. The work focused exclusively on the microbiological characterisation of cultured nematode species used as live feed organisms. No animal handling, invasive sampling, or experimental manipulation of fish larvae was conducted. Therefore, ethical approval from an institutional animal care or ethics committee was not required.

Thanks

The authors thank Assoc. Prof. Dr. Ş. Yasemin Tosun for her valuable contributions and constructive scientific input during the course of this study.

References

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Details

Primary Language

English

Subjects

Fish Pests and Diseases , Aquaculture

Journal Section

Research Article

Authors

Deniz Devrim Tosun ^*
0000-0001-6612-6624
Türkiye

Pelin Saliha Çiftçi Türetken
0000-0002-4377-1628
Türkiye

Remziye Eda Yardımcı
0000-0001-7737-8739
Türkiye

Early Pub Date

January 8, 2026

Publication Date

January 8, 2026

Submission Date

July 2, 2025

Acceptance Date

October 30, 2025

Published in Issue

Year 2026 Volume: 9 Number: 1

DOI

https://doi.org/10.3153/AR26001

IZ

https://izlik.org/JA35YM79ER

Cite

RIS / Bibtex

APA

Tosun, D. D., Çiftçi Türetken, P. S., & Yardımcı, R. E. (2026). Assessing the cultured bacterial flora of Nematodes Panagrellus redivivus and Radopholus similis as live feed for larval fish. Aquatic Research, 9(1), 1-7. https://doi.org/10.3153/AR26001

Assessing the cultured bacterial flora of Nematodes Panagrellus redivivus and Radopholus similis as live feed for larval fish

Abstract

Keywords

Öz

Supporting Institution

Project Number

Ethical Statement

Thanks

References

Details

Primary Language

Subjects

Journal Section

Authors

Early Pub Date

Publication Date

Submission Date

Acceptance Date

Published in Issue

DOI

IZ

Cite