Fish Disease and Treatment

Bacterial infection in aquaculture is mainly controlled by
the use of antibiotics. However, indiscriminate use of antibiotics is undesirable, as this often leads to the development of drug resistance and therefore to a reduction in the efficacy of drugs. There is urgent need to look for cheaper and more environmentally friendly alternative approaches to improve the immune system of fish than can act as stimulators to control diseases for sustainable aquaculture. In this study, bioactive extracts from five herbs were extracted using aqueous, chloroform and ethanol as solvents. Antimicrobial activity of aqueous extracts of Aegle marmelos, Emblica officinalis & Moringa oleifera, chloroform and ethanol extracts of Azadirachta indica & Toona sinensis were assessed against S. agalactiae Biotype 2 by using disk diffusion assay. The minimum inhibitory concentrations (MIC) of the herbs were determined by using well diffusion method. Aqueous extract of M. oleifera leaves resulted highest antimicrobial activity with a 13.1 mm inhibition zone and Aegle marmelos leaves extracts resulted lowest antibacterial activity with a 7.9 mm inhibition zone. Chloroform-extracted bioactive substance from Toona sinenses resulted lowest MIC value (0.15 mg/mL) with high efficacy against S. agalactiae Biotype 2. M. oleifera leaves could be a potential source of antimicrobial agents for sustainable aquaculture drug formulation.

To establish the effectiveness of EEG biofeedback using beta training as a relaxation technique and ultimately reducing anxiety levels of patients with confirmed unstable angina or myocardial infarction. Patients with confirmed unstable angina or myocardial infarction referred by cardiologists were recruited 2-3 days after their cardiac event from the cardiology wards. Their initial anxiety scores were determined using the Hospital Anxiety and Depression Scale. Those that returned for therapy underwent instrument feedback training using EEG every two weeks for a total of five sessions. EEG frequencies were measured for all sessions. Dropouts who did not participate in the program agreed to return 3 months later for the second psychological assessment. The study design was uncontrolled. Subjects had significantly lower anxiety scores at the second screening (p < 0.001), while the dropouts had significantly higher scores (p < 0.001). Beta training was effective in increasing sen...

Eight bacterial strains isolated from diseased rainbow trout (n55) and Atlantic salmon (n53) were
characterized by phenotypic and molecular taxonomic methods. The isolates were negative for the
Gram-reaction, non-motile, rod-shaped and catalase- and oxidase-positive. Colonies on solid
media were yellow, smooth, shiny and circular with regular edges. Growth occurred at 4–28 6C
(optimum, 15 6C) and with 0–3% NaCl (optimum, 0.5 %). Analysis of the 16S rRNA gene
sequence allocated the micro-organisms to the genus Chryseobacterium, with Chryseobacterium
soldanellicola PSD1-4T and Chryseobacterium soli JS6-6T as their closest relatives (96.9 and
97.1% sequence similarity, respectively). The levels of DNA–DNA hybridization towards these
nearest phylogenetic neighbours were below 17.1 %. The DNA G+C contents of strains
VQ-6316sT and VQ-4836s were 32.5 and 32.3 mol%, respectively. The predominant
menaquinone was MK-6 and the major fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C17 : 1v9c,
iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1v7c and/or C16 : 1v7t and/or iso-C15 : 0
2-OH). The eight isolates were classified as representatives of a novel species, Chryseobacterium
piscicola sp. nov., with strain VQ-6316sT (5CECT 7357T5DSM 21068T) as the type strain.

Viral Hemorrhagic Septicemia virus (VHSv) is an RNA rhabdovirus, which causes one of the world's most serious fish diseases, infecting >80 freshwater and marine species across the Northern Hemisphere. A new, novel, and especially virulent substrain—VHSv-IVb—first appeared in the Laurentian Great Lakes about a decade ago, resulting in massive fish kills. It rapidly spread and has genetically diversified. This study analyzes temporal and spatial mutational patterns of VHSv-IVb across the Great Lakes for the novel non-virion (Nv) gene that is unique to this group of novirhabdoviruses, in relation to its glycoprotein (G), phospho-protein (P), and matrix (M) genes. Results show that the Nv-gene has been evolving the fastest (k = 2.0x10-3 substitutions/site/year), with the G-gene at ~1/7 that rate (k = 2.8x10-4). Most (all but one) of the 12 unique Nv-haplotypes identified encode different amino acids, totaling 26 changes. Among the 12 corresponding G-gene haplotypes, seven vary in amino acids with eight total changes. The P-and M-genes are more evolutionarily conserved, evolving at just ~1/15 (k = 1.2x10-4) of the Nv-gene's rate. The 12 isolates contained four P-gene haplotypes with two amino acid changes, and six M-gene haplotypes with three amino acid differences. Patterns of evolutionary changes coincided among the genes for some of the isolates, but appeared independent in others. New viral variants were discovered following the large 2006 outbreak; such differentiation may have been in response to fish populations developing resistance, meriting further investigation. Two 2012 variants were isolated by us from central Lake Erie fish that lacked classic VHSv symptoms, having genetically distinctive Nv-, G-, and M-gene sequences (with one of them also differing in its P-gene); they differ from each other by a G-gene amino acid change and also differ from all other isolates by a shared Nv-gene amino acid change. Such rapid evolutionary differentiation may allow