The Chinese sturgeon (Acipenser sinensis Gray 1835) is an endangered anadromous sturgeon inhabiting the Yangtze River in China. In this study, the ultrastructure and morphology of spermatozoa was studied using transmission and scanning electron microscopy with a cryo-holder. The spermatozoon consisted of an elongated head with a distinct acrosome and nucleus region, a midpiece and a flagellum. ...

Palíková M., J. Mare‰ , J. J i rásek : Characteristics of Leukocytes and Thrombocytes of Selected Sturgeon Species from Intensive Breeding. Acta Vet. Brno, 1999, 68: 259–264. Analysis of leukocyte and thrombocyte characteristics in Acipenser baerii, Acipenser stellatus and Huso huso sturgeons at the age of about 200 days kept under intensive breeding conditions is presented. The differential le...

While the current expansion of conservation genetics enables to address more efficiently the management of threatened species, alternative methods for genetic relatedness data analysis in polyploid species are necessary. Within this framework, we present a standardized and simple protocol specifically designed for polyploid species that can facilitate management of genetic diversity, as exempli...

The purpose of this study has been to carry out a preliminary parasitological analysis of sturgeon specimens in the context of the presence of external parasites, and to determine their possible influence on the health of the fish. The examination of external parasites was performed on specimens of A. oxyrinchus oxyrinchus captured from an open system pond (the Fish Farm in Kuźniczka, Poland) a...

Techniques were developed to determine which life stages of fish are vulnerable to barotrauma from expansion of internal gases during decompression. Eggs, larvae, and juvenile hatchery-reared white sturgeon (Acipenser transmontanus; up to 91 days post hatch; d.p.h.) were decompressed to assess vulnerability to barotrauma and identify initial swim bladder inflation. Barotrauma-related injury and...

Basal ray-finned fishes possess a heterocercal tail in which the dorsal lobe containing the extension of the vertebral column is longer than the ventral lobe. Clarifying the function of the heterocercal tail has proved elusive because of the difficulty of measuring the direction of force produced relative to body position in the aquatic medium. We measured the direction of force produced by the...

A review of nine species the bee genus Epeolus Latreille, 1802 (Hymenoptera: Apidae, Nomadinae) currently known from Mongolia is given. Two new species, E. leleji sp. nov. and mongolicus are described. The following five newly recorded Mongolia: alpinus Friese, 1893, cruciger (Panzer, 1799), melectiformis Yasumatsu, 1938, nudiventris Bischoff, 1930, ruficornis Morawitz, 1875. lectotype designat...