Odontocete cetaceans use biosonar clicks to acoustically probe their aquatic environment with an aptitude unmatched by man-made sonar. A cornerstone of this ability is their use of short, broadband pulses produced in the region of the upper nasal passages. Here we provide empirical evidence that a beluga whale (Delphinapterus leucas) uses two signal generators simultaneously when echolocating. ...

For Canadian Arctic indigenous populations, marine mammal (MM) traditional foods (TFs) represent sources of both important nutrients and hazardous environmental contaminants. Food preparation is known to impact the nutrient and environmental contaminant content of processed items, yet the impacts of preparation on indigenous Arctic MM TFs remain poorly characterized. In order to determine how t...

Lactic acid bacteria are characterized as gram-positive, usually non-motile, non-sporulating bacteria that produce lactic acid as a major or sole product of their fermentative metabolism. In this study, the presence of lactobacilli were investigated in the intestines of beluga ( Huso huso) and Persian sturgeon ( Acipenser persicus ), inhabiting Caspian sea. The obtained data showed that various...

The recent evolutionary history, population structure and movement patterns of beluga whales in the western Nearctic were inferred from an analysis of mitochondrial DNA control region sequence variation of 324 whales from 32 locations representing five summer concentration areas in Alaska and north-west Canada. Phylogenetic relationships among haplotypes were inferred from parsimonious networks...

in the present study, the age- and sex-specific changes of various haematological and blood serum biochemical blood parameters of beluga ( huso huso ) were investigated. blood samples were collected from 4-, 6-, 7-, and 8-year-old beluga (n = 7 for each sex and age). the specimens were fed at a rate of 0.5-3% body weight per day. ast and ldh levels in 7- and 8-year-old fish of both sexes were s...

To compare the reproductive performance of the wild and cultured stocks of beluga, Huso huso males, some spermatological parameters were measured including: sperm motility, sperm density, spermatocrit and also fertilization rate, hatching rate and larval growth and survival rates. The semen samples were sampled from 11 wild spawners and 12 cultured brooders. A half of each semen sample was allo...

Natural killer (NK) activity, an important non-specific defense mechanism against viral infections and tumors, was demonstrated in beluga whales using two different methods: “‘Cr release and flow cytometry. Using the “Cr release assay, NK activity in belugas was shown to be higher against K-562 than against YAC-1 cell lines. Moreover, it was enhanced by the addition of human recombinant interle...