The sturgeon is a primitive actinopterigian fish that, unlike modern teleosts, possess a portal vascular system that connects a true median eminence with the anterior pituitary as in mammals. The occurrence and localization of corticotropin and corticotropin releasing factor-like immunoreactivies were examined in the brain of the sturgeon (Acipenser ruthenus L.) by immunocytochemistry with anti...

Acipenser persicus is one of the economically valuable fishes in the Caspian Sea. Due to the economical and cultural importance of sturgeons in the world, understanding of sturgeon reproduction is necessary for successful management of their populations in aquaculture and nature. To improve the culture methods and to facilitate captive breeding programs to support restocking, it is necessary to...

CO(2) tolerance in white sturgeon is associated with the ability to tightly regulate intracellular pH (pHi) despite a large reduction in extracellular pH (pHe) termed preferential pHi regulation. How this regulatory response affects whole animal metabolic rate is unknown. Accordingly, we characterized oxygen consumption rate ( [Formula: see text] ) and metabolically-relevant organismal and cell...

Approximately 8 weeks after a chlorine insult associated with the city water supply, shortnose sturgeon, Acipenser brevirostrum (L.), from one group presented with small (3-4 mm) irregular foci of cutaneous pallor that involved the dorsocranial integument with progressive ulceration of the nascent lesions. Various bacterial organisms were isolated from the cutaneous lesions, but not from the in...

samples from five sturgeon species including persian sturgeon (acipenser persicus), russian sturgeon (a. gueldenstaedti), great sturgeon (huso huso),ship sturgeon (a. nudi-ventris) and stellate sturgeon (a. stellatus) were collected from the south caspian sea. dna was extracted from the fins, eggs and skeleton muscle of the five species. rapd markers were used for identifying different kinds of...

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...

 Co-feeding of fish larvae with live food and formulated diet has been at the focus of fish nutritionists since last decade. In this study we tried to refine the feeding practices of great beluga sturgeon (Huso huso) larvae using different combinations of newly hatched Artemia urmiana nauplii and trout starter diet. Three replicate groups (250 fish/replicate) of first-feeding Huso huso ...

The structures of the pyruvate kinases isolated from rabbit and sturgeon muscles were compared. Both enzymes are composed of subunits of 56000 mol.wt. Amino acid compositions of the two enzymes are similar, but not identical. Examination of the peptides produced by CNBr cleavage demonstrated that there are at least some highly homologous regions in the two proteins. There are only two replaceme...