The major carps, including Labeo rohita, Cirrhinus mrigala and Catla catla are popular warm water fish species in Southeast Asia. Parasitic infestation is common among these major freshwater carps, hindering their growth and potentially causing mortality. This study aimed to identify Lernaea species morphologically and molecularly across selected fish farms of South Punjab. In total 125 Lernaea specimen were collected from 581 three distinct fish species including L. rohita, C. mrigala and C. catla across government and private fish farms located in Rajanpur (29°10´44´N, 70°33´01´E), Hasilpur (29°77´88´N, 72°54´71´E), Bahawalpur (29°38´´71´N, 71°63´40´E), and Multan (30°15´77´N, 71°44´39´E) from January to December 2021. These specimens were meticulously examined for precise morphological characterization by using a stereomicroscope after washing with 0.75% NaCl and identified by using Kabata’s identification key. For an accurate understanding of the anatomy of the Lernaea, the parasite was subjected to scanning electron microscopy. The specimens were subjected to molecular identification techniques based on 18S rDNA PCR. The results showed that the prevalence of parasite varied in different regions including Rajanpur (68.75%), Hasilpur (25%), Bahawalpur (12.11%) and Multan (22.5%). The fins, gills, skin and eyes were the most common infestation sites. Furthermore, the infestation rate varied among different fish species and regions, suggesting a potential influence of genetic & physico-chemical parameters on the observed differences in infestation levels. The phylogenetic analysis of 18S rDNA showed three distinct clades. Clade 1 included sequences from our study along with those from India, China and Russia, Clade 2 contains sequences from Iran, Australia, Iraq, and Japan while Clade 3 had only two sequences from China. This study offers the initial insight into Lernaea cyprinacea in Southern Punjab and sets the groundwork for future research on crustacean fish parasites, aiding in evaluating their economic impact on Pakistani fish farms.

To Cite This Article: Shah SQA, Mahmood K, Rashid MI, Naz H, Sohail ML, Naseer O, Ali S and Ahmad AS, 2024. Prevalence, Morphological and Molecular characterization of Lernaea cyprinacea isolated from major carps of Southern Punjab, Pakistan. Pak Vet J. http://dx.doi.org/10.29261/pakvetj/2024.308