Prevalence, site and tissue preference of myxozoan parasites infecting gills of cultured fish in Punjab (India)

Abstract

Native carp species cultured in Indian farms in Punjab (catla Catla catla, rohu Labeo rohita, mrigal Cirrhinus mrigala, exotic carps such as silver carp Hypophthalmichthys molitrix, grass carp Ctenopharyngodon idella, common carp Cyprinus carpio and a catfish Sperata seenghala) were examined for the presence of myxozoan parasites infecting gills. Firstly, the gills were examined under a zoom-stereomicroscope for the presence of plasmodia. The number of plasmodia per gill was counted to determine the index for the intensity of infection. Infected tissues were processed for histology, and 3−4 µm sections of infected gills were stained with haematoxylin & eosin and Luna's method. A total of 19 species of myxosporean were found infecting various cell types in the gills. Of these, 14 species belonged to the genus Myxobolus, 3 species to the genus Thelohanellus and 2 species to the genus Henneguya. Species belonging to the genus Myxobolus formed the interlamellar and intralamellar vascular (LV) type plasmodia, and species belonging to the genus Thelohanellus and Henneguya formed intrafilamental vascular (FV) type plasmodia. Mixed infections comprising 2, 3 or 4 different myxozoan species were noted in individual fish. The most common type of parasitism was polyparasitism due to 4 myxobolids co-occuring in fish with an infection rate of 23.16%. All species caused mild to severe haemorrhagic gill disease with little clinical symptomatology.KEY WORDS: Aquaculture · Parasite · Myxozoa · Gills · Freshwater fish Resale or republication not permitted without written consent of the publisherDis Aquat Org 118: [129][130][131][132][133][134][135][136][137] 2016 analysis. The selected ponds were polyculture having Labeo rohita Hamilton (1882), Catla catla Hamilton (1882), Cirrhinus mrigala Hamilton (1882), Ctenopharyngodon idella Valenciennes in Cuvier & Valenciennes (1844), Cyprinus carpio Linnaeus (1758), Hypophthalmichthys molitrix Valenciennes (1844) and Sperata seenghala Sykes (1839). Organs such as gills, gall bladder, liver, heart, gut, eyes, fins, scales and skin were examined and were fixed in Bouin's fixative for histopathological studies. Besides gills, the infection was also recorded in the scales, fins, liver and gall bladder. Each plasmodium was picked under a stereozoom binocular with fine forceps and ruptured in normal saline (0.85%) on a glass slide and examined under a light microscope for the presence of spores. Fresh spores were studied under a phase contrast microscope (Magnus MLX-TR). Polar filaments were extruded by treating the spores with 8% KOH. The number of spores per plasmodium were counted under low magnification on a glass slide. One plasmodium was ruptured on a slide with the help of a fine needle then covered with a coverslip, and the number of spores were counted; 3 to 4 plasmodia were ruptured to obtain the average number of spores.To make dry preparations, thin smears were air dried, fixed in methanol and stained with Giemsa. In the case of permanent (wet) preparations, smears we...

Occurrence of Protozoan Parasites From Climbing Perch, Anabas Testudineus From Open Waters of Bangladesh

“…However, Kaur and Katoch (2016) reported 65.15% (418 out of 1380 fishes) of native carp fish had mixed infection of Myxozoan species at a time and that result was slightly similar to this study. Multiple infections might be occurring due to sharing the same habitat by the host.…”

Prevalence, site and tissue preference of myxozoan parasites infecting gills of cultured fingerlings of Indian major carps in District Fatehgarh Sahib, Punjab (India)

“…There are alarming economical losses due to Myxobolus spp. infestation of the major carp in the nursery ponds as reported by Sanaullah and Ahmed (1980), Kaur and Katoch (2016), Kaur and Ahmad (2016) and Ahmad and Kaur (2017). The present study was therefore undertaken to investigate the prevalence rate, site preference and extent of damage caused by myxosporidian parasites in Punjab, India.…”

Species diversity of the genus Thelohanellus Kudo, 1933 (Myxozoa: Bivalvulida) parasitizing fishes in Indian subcontinent

“…Dermal lesion by Myxobolus and Thelohanellus were recorded to be common in the states of Andhra Pradesh and Karnataka (Kalavati and Nandi 2007). The most recent study by Kaur and Katoch (2016) have reported 3 gill infecting Thellohanellus species (T.bifurcata, T.dykovae, T. filli), 1 infecting liver (T. wallagoi) and 2 species infecting fins (T. boggoti, T. kalavatae). The studies conducted by Haldar (1998, 2003) have shown that hybrid carps were more susceptible to myxozoan infestation and in many instances they prove to be more prone to pathogenic effects leading to heavy mortality in culture systems.…”

“…Mondal et al (2014) recorded 12.5 % fin infection in L. rohita with T. caudatus (Pagarkar and Das 1993;Kaur et al 2015). Recently, Kaur and Katoch (2016) recorded 3 gill infecting Thelohanellus species in two locations i.e. gill lamellae (LV3 type) and gill filament (FV1 type), causing mild to severe histopathological changes.…”

“…The development of aquaculture during the last decade have resulted in much greater attention paid to problems posed by parasites and their impact on the fish health leading to constraints in the productivity (Kennedy 1994). In Punjab (India) fish culture is an upcoming industry having 8285 ponds practicing polyculture and myxozoan parasites have been recorded to be as the major pests (Kaur et al 2013a, b, Kaur et al 2014a, b, Kaur et al 2015, Kaur and Katoch 2014, 2016. This synopsis has been compiled in order to emphasis on the 52 Indian thellohenelloid species infesting major and minor carps, and pin pointing the pathogenic ones and symptamotology as per respective studies (Table 1).…”