Neeshma Jaiswal

Ecological morphotaxometry of trematodes of garfish (Teleostomi: Belonidae) from Gangetic riverine ecosystem in India. I. Morphology and taxometric assessment of Cephalogonimus yamunii n.sp.

A new endoparasitic fluke, Cephalogonimus yamunii n.sp. is described from the intestine of freshwater fish Xenentodon cancilla (Belonidae). The worms could be differentiated from C. amphiumae (Chandler 1932), C. apognichthysi (Gupta and Puri 1982), C. hanumanthai (Agrawal and Agarwal 1984), C. salamandrus (Dronen and Lang 1974), C. simhai (Singh 2010) and C. vesicaudus (Nickerson 1912) in a unipartite seminal vesicle, genital pore subterminal anteriorly, opening at the hind end of oral sucker, equatorial or sub-equatorial testes, besides other morphological attributes of shorter body and pharynx, larger oesophagus and oral sucker, smaller ventral sucker, testes, cirrus sac and ovary, and a terminal excretory pore. Taxometric substantiation has been presented by using Polythetic Divisive Classificatory System, and ecological attributes have been evaluated to validate specific distribution patterns in population dynamics of the new species in simultaneous contributions.

A new species of Neolebouria Gibson, 1976 (Opecoelidae: Plagioporinae) from the whitecheek monocle bream, Scolopsis vosmeri (Perciformes: Nemipteridae), from the Panjim coast at Goa, with a checklist of parasites previously reported from this fish

Neolebouria capoori n. sp. (Opecoelidae: Plagioporinae) is described from the whitecheek monocle bream, Scolopsis vosmeri (Bloch) (Perciformes: Nemipteridae) from the Panjim coast on the central west coast of India at Goa. The new species differs from both Neolebouria cantherhini (Li, Qiu & Zhang, 1988) as originally described from Thamnaconus modestus (Günther) (syn. Cantherines modestus Günther ) and Neolebouria confusum (Overstreet, 1969) as originally described from Ocyurus chrysurus (Bloch) by having the cirrus sac surpassing the ventral sucker posteriorly in N. cantherhini and being entirely preacetabular in N. confusum compared to terminating near the midlevel of the ventral sucker in N. capoori n. sp. The new species is most similar to N. confusum, but it further differs from this species by having the vitelline fields terminating near the level of the esophageal bifurcation compared to terminating near the level of the posterior margin of the pharynx, a larger sucker ratio (1:1.7-1:2.0 compared to 1:1.4-1:1.7), a somewhat shorter cirrus sac relative to body length (160-448, representing 9-18% of the body length compared to about 367, representing 22%), and the egg of the new species has a boss at the anopercular end that is not present in N. confusum. This study represents the first report on an opecoelid from S. vosmeri. A review of the parasites reported from S. vosmeri is included.

Keys to the species of Neolebouria Gibson, 1976 (Digenea: Opecoelidae: Plagioporinae), with a redescription of Neolebouria truncata (Linton, 1940)

Three keys to the species of Neolebouria Gibson, 1976, representing three body types, are provided based on the location of the genital pore relative to the intestinal bifurcation. These are: the lanceolata body type, where the genital pore is clearly prebifurcal; the diacopae body type, where the genital pore is located at or near the level of the intestinal bifurcation; and the maorum body type, where the genital pore is clearly postbifurcal. Fifteen species were assigned to the lanceolata body type; eight species to the diacopae body type; and four species to the maorum body type. Neolebouria truncata (Linton, 1940) is redescribed and N. georgiensis Gibson, 1976 is reinstated as a valid species. Neither N. georgiensis, nor N. antarctica Szidat & Graefe, 1967 (syn. Crassicutis antarcticus Szidat & Graefe, 1967), as described by Zdzitowiecki et al. (1993), represent N. antarctica, as originally described, and N. georgiensis and N. antarctica, as described by Zdzitowiecki et al. (1993), may be conspecific.

Accentuated Molecular Detection Technique to Segregate and Identify Helminths of Fish through High Resolution Melting (HRM) Analysis

Real-time PCR coupled with high-resolution molecular (HRM) analysis was conducted to target the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA. The latter acted as a genetic marker to identify and distinguish two anisakid and one cucullanid species parasitizing marine and freshwater fish. Unique and distinct characteristics of HRM patterns were produced for each of the three roundworms investigated. The melt profiles and threshold of the cycles (Ct values), at which amplification commenced, for Anisakis simplex (Rudolphi), Contrcaecum osculatum (Rudolphi) Dujardin, Contrcaecum sp. and Dacnitoides cotylophora (Ward and Magath) were diagnostic for species. The molecular analyses by sequencing and comparing the internal transcribed spacer (ITS) of the ribosomal DNA of Dacnitoides, Anisakis and Contrcaecum assays established their distinct identity. The present investigation propagates molecular-phylogenetic and morpho-molecular analysis to characterize diagnostic constituents of cucullanid and anisakid roundworms.

Bioinvasion: a paradigm shift from marine to inland ecosystems

Anisakidosis is one of the most fearsome zoonotic food borne disease in aquaculture. The natural infections by anisakidoids or related variety in freshwater fish are not known, though sporadic experimental reports are available abroad (Butcher and Shamsi 2011). Invasive severity of anisakidoids in fish from Gangetic riverine ecosystems, i.e., in river Ganges at Fatehpur and Allahabad, as well as in river Yamuna at Allahabad, and molecular heterogeneity among these worms have been extensively investigated. The pathways of transmission of non-native alien species due to long distance migratory habits of Rita rita, man-made alterations including dredging in long stretches of the river bed of Ganges to facilitate ballast water transfer mechanism owing to the commercial ship movements between Haldia and Allahabad; and sudden water chemistry (salinity, hardness, alkalinity) alteration (due particularly to rainy period) oriented micro-fauna interchange are identified, and remedial measures suggested.

Helminth Infections Mediated DNA Damage: Mechanisms and Consequences

According to an estimate, the chronic infections caused by certain pathogens such as viruses, bacteria, fungi and parasites contribute to about 18% of the global burden of cancer; helminth infections attributing to only small part of it. Carcinogenesis associated with the helminthes infections induced development of cancer is a complicated event involving several different mechanisms varying from one species of parasite to another. Parasite infections evoke immune responses in the host which finally result into inflammatory reactions. The chronic inflammatory processes produce reactive oxygen species (ROS) and reactive nitrogen species (RNS). These free radicals may cause DNA damage resulting into genetic instabilities and occurrence of malignancy. The parasites or their eggs or their excretory-secretary products exhibit potential to induce proliferation of some cells in the affected tissues which harbor DNA damage. The existing reports indicate that helminth infections may trigger cancer in the organs of their infection for example Clonorchis sinensis and Opisthorchis viverrini may induce cholangiocarcinoma (cancer of gall bladder and hepatocarcinoma) and Schistosoma haematobium and its other species are known to cause urinary bladder cancer. In many cases of helminth infections mediated carcinogenesis, the DNA damage by free radicals or inflammatory responses at damaged host tissues is demonstrated. Therefore the knowledge about the mechanisms of helminthes mediated DNA damage may be of great importance in management of parasite infections and reduction of incidences of parasites induced cancer thereby improving the quality of human lives. This article presents an updated account of helminthes infection mediated genotoxicity, DNA damage mechanisms and consequences.