Prevalence and infestation intensity of a piscicolid leech, Zeylanicobdella arugamensis on cultured hybrid grouper in Brunei Darussalam
Aquaculture study published in Vet Parasitol Reg Stud Reports (2020)
Abstract
Grouper is an important food fish due to its commercial value. A major production constraint in culturing grouper is that the fish can be fatally affected by leeches and diseases. Leeches are an ectoparasite of grouper, which can cause significant loss in fish number, and thus controlling their prevalence is indispensable as a tool of aquaculture management. In order to understand the prevalence and infestation intensity of a piscicolid leech Zeylanicobdella arugamensis, field observation of hybrid grouper was conducted in two aquaculture farms in Brunei Darussalam. The prevalence rates were 100% for the two farms throughout the study period, while the infestation intensity levels were significantly different between the two farms. The farm with the higher salinity ranging from 26 to 28 psu was found to have a significantly higher number of leeches (505 ± 271 leeches fish-1; mean ± SD) than the other farm with the lower salinity ranging from 17 to 23 psu that had 27 ± 23 leeches fish-1, although the ranges of recorded water temperatures overlapped between the two farms. This study suggests salinity might be an important factor in the propagation of Z. arugamensis. Furthermore, the prevalence and intensity of the leech in Brunei Darussalam were higher than those reported in other Southeast Asian countries. These results indicate that the hybrid grouper culture in Brunei Darussalam might have a higher risk in disease than those countries.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Field study of Z. arugamensis leech infestation prevalence (100%) and intensity on cultured hybrid grouper in Brunei, with salinity 26-28 psu farms harbouring significantly more leeches than 17-23 psu farms.
Why This Matters for Hirudotherapy
This field study examined the prevalence and infestation intensity of the piscicolid leech Zeylanicobdella arugamensis on cultured hybrid grouper at two aquaculture farms in Brunei Darussalam, finding 100% prevalence at both sites and significantly higher leech counts at the farm with higher salinity (505 ± 271 vs. 27 ± 23 leeches per fish). The authors suggest salinity may be an important factor in leech propagation and note higher infestation levels than reported elsewhere in Southeast Asia. For ASH's domain, this study has essentially no direct relevance: it concerns an ectoparasitic leech affecting fish aquaculture, with no connection to hirudotherapy, the leech secretome, or any medicinal application. The species is not a medicinal leech, and no bioactive compounds or therapeutic properties are investigated.
Citation
Prevalence and infestation intensity of a piscicolid leech, Zeylanicobdella arugamensis on cultured hybrid grouper in Brunei Darussalam.
Azmey S et al. · Veterinary parasitology, regional studies and reports, 2020
Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026