Effects of Different Diets on Population Growth of Cultured Cyclopoid Copepod, Mesocyclops leuckarti (Claus, 1857)

In recent times aquaculture has become an increasingly important part of the world economy. Copepods play major roles in pond ecosystems serving as food for small fish, micro-predators on fish and other organisms, fish parasites, intermediate hosts of fish parasites and hosts and vectors of human diseases like cholera. Growth, reproduction and biochemical composition were analyzed for the copepod Mesocyclops leuckarti fed on four diets and their ratio like Bakers yeast (B), Baker’s yeast+ Wheat flour (BW, 1:2), Bakers yeast + Chicken manure (BC, 1:2) and Bakers yeast + Chicken manure + Wheat flour (BCW, 1:2:2). The mean peak density of the copepod population was 569 individual/lit, for all four diets used. The highest was 587 individual/lit, on diet having combination of Bakers yeast, Chicken manure and Wheat flour (BCW). A small copepod Mesocyclops leuckarti tends to have a short life span and it was found to be important food items for fish larvae.

Molecular characterization and phylogenetic analysis of cyclopoid copepod Mesocyclops leuckarti using mtCOI

Copepods are the most abundant metazoan zooplankton amongst multicellular animals. The present study was performed to establish the sequence variation of partial mitochondrial Cytochrome c Oxidase I gene (COI) from Mesocyclops leuckarti collected from the Retteri Lake, Chennai in order to identify and describe their genetic divergence along with the phylogenetic relatedness with other species. DNA of individual M. leuckarti was extracted and the partial mitochondrial COI gene was successfully amplified using the universal primers LCO-1490 and HCO-2198. A 576bp partial mitochondrial COI gene sequence was obtained. Analysis of partial COI sequences of M. leuckarti exposed 93% similarity amongst all the individual of copepods selected from Genbank. The obtained COI sequences of Cyclopoid copepod was confirmed with BLAST analysis. Phylogenetic analysis of M. leuckarti along with selected out groups from different taxa level further supports the clarity and maintained the authentic of taxonomy up to the subclass level: Copepoda. The results showed that, the COI barcoding of cyclopoid copepod species could be distinguished from the others very clearly. Thus, it strongly indicated that COI may be a useful construction of a comprehensive DNA barcode database for copepods inhabiting the freshwater bodies in Chennai.

Palm house – biodiversity hotspot or risk of invasion? Aquatic invertebrates: The special case of Monogononta (Rotifera) under greenhouse conditions

Greenhouses form favourable conditions for establishing stable populations of native as well as invasive alien microinvertebrates. Investigations of palm houses have a long tradition and native, alien and new species for science have been found in many of them. The examined pond and some microreservoirs in Bromeliaceae and Agavoideae in Pozna´n Palm House (Poland) sampled in 2012, appeared to contain representatives of Rotifera (64 species), Copepoda (2 species), Polychaeta, Acari and Insecta larvae. The most abundant Rotifera species were: Anuraeopsis fissa Gosse, 1851, Ascomorpha ecaudis Perty 1850, Euchlanis dilatata Ehrenberg, 1832, Pompholyx sulcata Hudson, 1885 and Trichocerca rousseleti Voight, 1902. Moreover, rotifers considered to be rare in Poland, i.e., Asplanchna herricki De Guerne, 1888, Collotheca pelagica Rousselet, 1893, Colurella sulcata Stenroos, 1898, Gastropus minor Rousselet, 1892 were also detected in Pozna´n Palm House. Two recorded Copepoda species were Phyllognathopus viguieri (Maupas, 1892) found in agave microreservoirs and Mesocyclops leuckarti (Claus, 1857) found in reservoir with aquatic plants. For biodiversity evaluation of rotifers Margalef’s and Shannon-Wiener’s indexes were used and in order to determine species richness the Simpson index was calculated. Additionally, a complete list of all aquatic invertebrates is presented, i.e., Plathelmintes (11 species), Nemeretea (2 species), Oligochatea (13 taxa), Polychaeta (7 species), Gastrotricha (13 taxa) and Copepoda (1 species) previously recorded in Pozna´n Palm House. To sum up, Palm houses create a convenient habitat for a prevalence of native and introduced invertebrates and are a putative source of alien species, possibly facilitating their release to the environment.