Detection and characterization of potentially pathogenic Aeromonas sobria isolated from fish Hypophthalmichthys molitrix (Cypriniformes: Cyprinidae).

The current study focuses on the detection and characterization of potentially pathogenic Aeromonas sobria from fish silver carp (Hypophthalmichthys molitrix). Assessment of clinical, microbiological, pathological and biochemical characteristics of A. sobria were taken into account in order to understand the epidemiology, frequency and occurrence of this infection. Clinically the infected fish (H. molitrix) was observed for various types of symptoms. A total of 33 colonies of A. sobria strain were isolated from 20 cultured H. molitrix, collected from controlled fish pond. Microscopic examination revealed that the strains were rod-shaped, Gram negative bacteria. The revealed percent probability identification of A. sobria from the biochemical characterization in VITEK system was 93% with gram negative (GN) card. The histopathology of Gills caused by this bacterium, A. sobria indicate haemorrhagic gill epithelia and epithelial hyperplasia. Lamelar epithelial hypertrophy and hyperplasia with degenerative changes of the epithelium and hypertrophic epitheliocystis infected cells on gills of H. molitrix were observed during the present study.

Enhanced production of α-amylase by Penicillium chrysogenum in liquid culture by modifying the process parameters.

In this paper, we have assessed the role of changing physicochemical parameters and substrate types on the production of α-amylase enzyme from Penicillium chrysogenum, with a view to determining the optimal conditions required for its maximum production. The findings of this research revealed that, at pH 6 using linseed oil cake as substratum, α-amylase enzyme production was maximum (550.0 U/mL), when the fungi was incubated for 6 days at 30 °C in 0.1 M acetate buffer. Further, reasonably good production of the α-amylase enzyme was also observed at pH 9 with all the experimented carbon sources as substrates. Moreover, statistical analysis, using analysis of variance (ANOVA) carried out to study the impact of different studied parameters on the α-amylase enzyme production revealed that incubation period of 6-18 days is highly significant (p = 0.01) factor in amylotic activity of the P. chrysogenum. Under the researched out optimal conditions, P. chrysogenum is an economically viable option for the industrial and biotechnological production of α-amylase enzyme.

Metacercariae of Clinostomum schizothoraxi Kaw, 1950 (Digenea: Clinostomatidae) in Carassius carassius (Linnaeus) under different environmental conditions.

This report addresses the possible impacts of local habitat characteristics on the metacercariae of Clinostomum schizothoraxi Kaw, 1950 infecting crucian carp, Carassius carassius (Linnaeus), from three lakes in Kashmir. The lakes chosen encompass an extremely wide gradient in trophic status--Manasbal (less polluted and mesotrophic), Dal (moderately polluted and eutrophic) and Anchar (strongly polluted and hypertrophic). The results indicate that infrapopulation-level descriptors of abundance of C. schizothoraxi in fish differed between the three lakes and revealed that the infection levels were greater at Anchar Lake. Furthermore, the prevalence, mean abundance and mean intensity of infection also changed during the period of investigation along the seasonal gradient of water temperature. The fact that the abundance patterns of the parasite differed in different populations of the same host provided a unique opportunity for a comparative study on the temporal variations in infection patterns attained during different seasons. In particular, the lake environments showed a high degree of variability in the density profiles of mollusc intermediate hosts and, thus, the differences in the infection status of crucian carp were derived on the basis of intermediate host population size which, in turn, was influenced by the trophic characteristics of the three lakes.