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Several steps of sturgeon somatic cell nuclear transfer (SCNT) have been recently established, but improvements are needed to make it a feasible tool to preserve the natural populations of this group of endangered species. The donor cell position inside the recipient egg seems to be crucial for its reprogramming; therefore by injecting multiple donor somatic cells instead of a single cell with a single manipulation, we increased the potential for embryo development. Using the Russian sturgeon Acipenser gueldenstaedtii as a multiple cell donor and sterlet Acipenser ruthenus as the non-enucleated egg recipient, we obtained higher proportion of eggs developing into embryos than previously reported with single-SCNT. Molecular data showed the production of a specimen (0.8%) contained only the donor genome with no contribution from the recipient, while two specimens (1.6%) showed both recipient and donor genome. These findings are the first report of donor DNA integration into a sturgeon embryo after interspecific cloning. In all, we provide evidence that cloning with the multiple donor somatic cells can be feasible in the future. Despite the fact that the sturgeon cloning faces limitations, to date it is the most promising technique for their preservation.

Lake sturgeon are arguably the largest and most unique freshwater fish in North America. Unfortunately their uniqueness includes many characteristics that make them especially vulnerable to anthropogenic impacts including overfishing, habitat fragmentation, and degradation. For approximately 100 years lake sturgeon populations across North America have either been in decline and (or) have experienced a sluggish recovery. While this is partly due to lake sturgeon life history, most researchers agree that habitat fragmentation and degradation are currently the highest risk to the species. Though most lake sturgeon populations are depressed, there are a few exceptions that offer a glimpse into what a stable population or recoverymaylook like. The following review highlights such instances as well as what is known and more importantly what is not known about this unique species. Specifically, we highlight the need for improved and organized sharing of raw data given the fact that many researchers do not have access to the plethora of information available to others (e.g., otoliths for aging). We examine the varying life history and diet choices of this plastic species offering hypotheses for differences in migration routes and distances as well the differing recovery rates found across their range.We highlight myths about the species providing evidence that they may not be as long lived and fecund as previously thought. We examine the lake sturgeon's current legal status across North America including the efforts of nonprofit groups that have had success in increasing population numbers. Most importantly, we highlight logistical problems faced by researchers and data gaps in the literature that must be filled to increase the odds of a successful recovery. Alongside the data gaps, the recovery of this species is fraught with political and industrial road blocks that are as varied as its current recovery. Subsequently, as is the case with many species, its survival will come down to solid scientific knowledge and the value placed on it by society.

Sturgeons (Chondrostei: Acipenseriformes) display markedly disjunction distributions with a wide distribution in the northern hemisphere. Their unique benthic specializations and conserved morphology, evolutionary age, the variation in their basic diadromous life history, and the large public interest due to their near extinction or critically endangered status make sturgeons and paddlefishes interesting groups for molecular and cytogenetic studies. From altogether 27 acipenseriform species, seventeen species are supposed to be critically endangered, two species are classified as endangered, four species are vulnerable and other species are near threatened or in low-risk (IUCN Red list 2010). Sturgeons are characteristic by a relatively high number of chromosomes in cell nuclei and differences in ploidy levels. Sturgeons displayed a strong tendency for interspecific and inter-generic hybridization under altered environmental conditions as well as under conditions of artificial propagation. Almost 20 inter-specific sturgeon hybrids were described. The decrease of natural populations and tendencies leading to restocking may result in uncontrolled restocking, production of hybrid specimens (even with non-native species) and decrease of natural genetic diversity of species in their original distribution area. Identification of parental species of natural hybrids by modern methods of molecular biology is still not easy. Here, we attempt to briefly summarize the major aspects of sturgeon genetics and cytogenetics related to ploidy levels and interspecific hybridization.

The first book of its kind to explore this magnificent creature, this collected volume captures many aspects of the remarkable Great Lakes sturgeon, from the mythical to the critically real. Lake sturgeon are sacred to some, impressive to many, and endangered in the Great Lakes. A fish whose ancestry reaches back millions of years and that can live over a century and grow to six feet or more, the Great Lakes lake sturgeon was once considered useless, then overfished nearly to extinction. Though the fish is slowly making a comeback thanks to the awareness-raising efforts of Native Americans, biologists, and sturgeon supporters, it remains to be seen if conservation and stewardship will continue to the degree this remarkable animal deserves. Blending history, biology, folklore, environmental science, and policy, this accessible book seeks to reach a broad audience and tell the story of the Great Lakes lake sturgeon in a manner as diverse as its subject.

Total of 29 sturgeons (two species; length 8-37 cm) originating from fish farms in northern Poland with a known KHV history in common carp or koi in the area were examined: 15 Russian sturgeons, Acipenser gueldenstaedtii, with clinical signs of a disease and 14 asymptomatic Atlantic sturgeons, A. oxyrinchus. The preliminary results were obtained using PCR. Those findings were subsequently confirmation by nested PCR. The latter procedure consists of sequence analysis of PCR products and direct detection of KHV infected cells in tissue materials by in-situ hybridization on nucleic acid level or indirect immunofluorescence on KHV protein level. KHV genome parts were found in nine Russian sturgeons and four Atlantic sturgeons. Therefore a viral diagnostics is highly recommended not only for sturgeons obtained from the environment but also for fertilized eggs, fry, and fish intended for re-stocking measurements of inland waters

The Poucachiche family invite us to fish some sturgeon with them.

The effects coelomic fluid removal method and de-adhesion substances (milk solution, starch suspension and urea-NaCl-tannic acid solutions) had on fertilization rates and hatching success and time of Siberian sturgeon, Acipenser baerii Brandt were compared. It was concluded that rinsing Siberian sturgeon eggs prior to fertilization is recommended when there is abundant and viscous coelomic fluid. De-adhesion with milk ensures the shortest and most synchronous hatching of Siberian sturgeon larvae

This Sturgeon Hatchery Manual includes the latest available scientific research findings and experiences and compiles advice given in earlier manuals and handbooks on sturgeon culture and reproduction practices. This document can be considered an update of the Sturgeon Breeding and Rearing Handbook (Chebanov, Galich and Chmyr, 2004), which was published in the Russian language. The Sturgeon Hatchery Manual was prepared in response to numerous requests for practical guidance on this subject from the Central Asian and Caucasus region to the Food and Agriculture Organization of the United Nations (FAO). This manual is targeted particularly at sturgeon farmers, sturgeon hatchery operators, hatchery technicians, and fisheries and aquaculture managers involved in sturgeon aquaculture development and the restocking and rehabilitation of sturgeon populations in the countries around the basins of the Black and Caspian seas. It aims to provide a practical handbook of modern sturgeon hatchery practices and management. The manual is available in the English, Russian and Turkish languages. The manual starts with a chapter on the taxonomy, biology, distribution and life histories of Azov-Black and Caspian Sea sturgeons. Subsequent chapters discuss the following aspects of sturgeon hatchery practices: hatchery design, collection and transportation of wild broodstock, broodstock management, spawning and gamete processing, fry and fingerling rearing, production of live feeds, the technology of artificial reproduction, ecological- morphological and ethological-physiological express estimation of larval and fingerling (fry) viability, release of fingerlings into natural waterbodies, the formation of domesticated broodstock, basic sanitation and fish health measures, tagging, and early sexing and maturity determination in live sturgeons using ultrasound techniques. The manual also contains an extensive list of references, a list of Acipenseriformes and numerous figures, photographs and tables to support the guidance given on the various hatchery practices

The parasitic relationship between the leech, Caspiobdella fadejewi, and the juvenile Atlantic sturgeon, Acipenser oxyrinchus is presented. The aim was to determine leech invasion intensity and extensity and describe parasite feeding location preferences on the ventral side of the snout and gill cavities. The prevalence of C. fadejewi occurrence was 37.3 percentage, at an intensity of one to eight leeches. It was confirmed that the intensity of leech occurrence was positively correlated with sturgeon total length. The host-searching mechanism is most probably based on positive phototaxis. This is the first record of C. fadajewi from A. oxyrinchus

The collecting eggs method from sturgeon using a catheter is described. A catheter made of artificial material is introduced through the urogenital opening into the body cavity of the female, and this permits opening the ovarian funnels. Next, exterior abdominal massage creates pressure that forces eggs into a collection receptacle. This method has been applied since 2004 to culture sturgeon fishes. The catheter method of collecting fish eggs can be an alternative method thanks to its low invasiveness and ease of application