The stinging catfish is widely cultivated in South Asia because of its nutritional value, environmental tolerance, and suitability for high-density production. Growing demand has encouraged rapid expansion of hatchery-based propagation in Bangladesh. However, restricted broodstock pools, repeated use of related parental lines, and inconsistent genetic management may reduce diversity and produce domestication-related changes in growth, morphology, and fitness. Wild populations, by contrast, experience diverse habitats, food resources, and hydrological conditions that can maintain broader phenotypic variation. Although conventional measurements can reveal general size differences, they may overlook subtle, coordinated changes in body shape. A detailed comparison was therefore needed to determine whether farmed and wild catfish populations possess distinguishable morphologies and to identify the anatomical regions driving this divergence.
A study (DOI: 10.48130/jai-0026-0001) published in Journal of Applied Ichthyology on 12 June 2026 by Imran Parvez's team, Hajee Mohammad Danesh Science and Technology University, could help hatcheries select more diverse broodstock, preserve valuable wild morphotypes, limit the loss of phenotypic diversity, and support more resilient and sustainable catfish aquaculture.
The researchers collected 114 catfish between October 2024 and June 2025 from farms in Bogura, Dinajpur, and Mymensingh and from the Garbheswari River. They photographed each specimen under standardized lighting and camera conditions, then digitized 15 anatomical landmarks covering the head, trunk, fins, and caudal region. Generalized Procrustes Analysis removed differences caused by size, position, and orientation, while regression against centroid size corrected for allometry. The team subsequently examined shape variation using the coefficient of variation, principal component analysis, relative warp analysis, Mahalanobis and Procrustes distances, multidimensional scaling, hierarchical clustering, discriminant function analysis, and canonical discriminant analysis. Permutation testing and leave-one-out cross-validation were used to evaluate statistical robustness and classification performance. Centroid size did not differ significantly among populations, indicating that the detected patterns principally represented shape rather than overall body-size variation. Wild Garbheswari River fish showed the greatest within-population variability, particularly at landmarks associated with the head and trunk. This pattern suggests greater phenotypic plasticity under heterogeneous natural conditions. Farmed fish showed narrower variation, consistent with morphological homogenization under controlled rearing environments. The first two principal components explained 94.31% of total shape variation. The first component alone accounted for 88.18% and mainly represented differences in body depth, head profile, and fin-base position; the second captured changes in caudal-peduncle tapering, opercular width, and anal-fin base length. All pairwise Mahalanobis distances exceeded 2.0, demonstrating clear differentiation among the four populations. Bogura fish occupied the most distinctive position in multivariate analyses, while clustering placed the Garbheswari River and Dinajpur populations together and grouped Bogura with Mymensingh in a separate major cluster. Discriminant analysis produced minimal overlap and classified 96.7% of wild river specimens correctly. Canonical discriminant analysis further identified one dominant axis of separation, with a canonical correlation of 0.844. Variation in the anterior body, trunk depth, and caudal peduncle contributed strongly to population discrimination. Because the study assessed morphology rather than DNA, the patterns may reflect environmental effects, domestication, geographic separation, or potential genetic structuring.
Overall, the study demonstrates that landmark-based geometric morphometrics can efficiently distinguish farmed and wild H. fossilis populations and detect biologically meaningful changes that conventional measurements may miss. The greater variability retained by river fish highlights the conservation value of wild morphotypes, while differences among farms indicate that hatchery management practices can produce distinct morphological outcomes. Incorporating carefully evaluated wild broodstock, broadening breeding populations, and routinely monitoring body-shape diversity could help preserve adaptive traits and strengthen the long-term sustainability of stinging catfish production.
###
References
DOI
10.48130/jai-0026-0001
Original Source URL
https://doi.org/10.48130/jai-0026-0001
About Journal of Applied Ichthyology
Journal of Applied Ichthyology (e-ISSN 1439-0426; p-ISSN 0175-8659) is an open-access, peer-reviewed journal dedicated to publishing high-quality research on applied ichthyology, aquaculture, and marine fisheries, including management of fisheries resources, fisheries ecology, fish health and pathology.