Sturgeon Production Research Articles

First evidence of WW superfemale for hybrid sturgeon, the bester (Huso huso × Acipenser ruthenus)

Sex control offers a promising strategy for cost-effective aquaculture in certain fish species. Sturgeons, which utilize the ZZ/ZW sex determination system, are particularly valuable for producing high-priced black caviar derived from female roes, making all-female production highly desirable. However, this goal has yet to be fully realized. In this study, we identified a short genomic region specific to the Z and W genomic scaffolds of Acipenser ruthenus and developed a polymerase chain reaction (PCR) method to distinguish between the Z and W alleles. Using PCR, 1280 A. ruthenus, 66 A. baerii baerii, and 31 F2 hybrids of besters (Huso huso × A. ruthenus) were genotyped, revealing either a single Z amplicon or dual Z plus W amplicons in an approximately 1:1 ratio. This indicates successful discrimination of the ZZ/ZW genotypes. Additionally, gonadal sex was identified in 145 of the genotyped individuals, all of which corresponded to their genetic sex. Gynogenetic individuals of the F3 bester hybrid were also genotyped, with 25 of 112 (22.3 %) exhibiting only W amplicons, identifying them as WW superfemales. These findings contribute to the advancement of all-female sturgeon production for aquaculture, facilitating the efficient farming of these highly prized species.

Sturgeon Parasites: A Review of Their Diversity and Distribution

Sturgeon species have inhabited the world’s seas and rivers for more than 200 million years and hold significant taxonomic significance, representing a strong conservation interest in aquatic biodiversity as well as in the economic sector, as their meat and eggs (caviar) are highly valuable goods. Currently, sturgeon products and byproducts can be legally obtained from aquaculture as a sustainable source. Intensive farming practices are accompanied by parasitic infestations, while several groups of parasites have a significant impact on both wild and farmed sturgeons. The present article is a review of common sturgeon parasites from the genus: Protozoa, Trematoda, Crustacea, Nematodes, Monogenea, Hirudinea, Copepoda, Acanthocephala, Cestoda, Polypodiozoa, and Hyperoartia, while also addressing their pathology and statistical distribution.

Poaching and illegal trade of Danube sturgeons

A market study on sturgeon products in the Lower Danube countries (Bulgaria, Romania, Serbia and Ukraine) resulted in a total of 149 samples of caviar and meat, which we subjected to genetic-isotope analyses. The samples comprised 31 samples (21%) of illegal wild-caught origin, 17 samples (11.4%) sold in violation of CITES and EU regulations, and 47 cases (32%) of consumer deception. Although poaching and illegal wildlife trade are often considered a problem in developing countries, these findings bear evidence that a high ratio of poached sturgeon products originates from EU and accession candidate states. Therefore, caviar and sturgeon trade urgently needs improvement to ensure that sturgeon populations will have a future.

Co-isolated bacteria from septicemia of female Siberian sturgeon broodstock: Lactococcus petauri resisting Aeromonas hydrophila infection

The rapid development of sturgeon aquaculture has satisfied the market demand for sturgeon products and effectively avoided the dilemma of a sharp reduction of wild resources. However, the risk of infectious death after artificial propagation of female Siberian sturgeon (Acipenser baerii) has threatened sturgeon farming. To find out the pathogeny, bacteria were isolated from the female A. baerii broodstock infection, and their effect was researched. The results showed that the strain JLAH was identified as Aeromonas hydrophila by the phylogenetic tree of 16S rRNA gene with β-hemolytic activity and typical virulence genes of hemolysin (hlyA) and cytotoxic enterotoxin (alt). The other strain JLlg08PX was identified as Lactococcus petauri by genome sequencing analysis, with the ANI value of 98.55% and the dDDH value of 86.00%, which was the closest relative to L. petauri 159469T. In vivo, the cumulative mortality of A. hydrophila infection reached 88.89% with necrosis of hepatocytes and the damage of valvular intestinal as consistent with the spontaneous symptoms. Interestingly, co-infection with A. hydrophila and L. petauri could decrease the mortality to 33.33%, and the pathological damages were alleviated in the liver and valvular intestinal. No death or clinical symptoms were observed in L. petauri infection by intraperitoneal injection, oral gavage, or immersion. In vitro, the growth of A. hydrophila, A. veronii, and Yersinia ruckeri was inhibited by the cell-free supernatant (CFS) of L. petauri. Taken together, A. hydrophila is the etiological agent, while the co-isolated L. petauri could resist A. hydrophila infection. This study enriched the understanding of the parental sturgeon infection after artificial propagation and enlightened the prevention strategies of antagonistic strain in Aeromonas infection.

The Influence of Consortia of Beneficial Microorganisms on the Growth and Yield of Aquaponically Grown Romaine Lettuce

This study evaluated the effects of fish farm wastewater from the production of hybrid sturgeon (Acipenser gueldenstaedtii Brandt × Acipenser baeri Brandt) on the growth and quality parameters of romaine lettuce (Lactuca sativa var. longifolium cv. “Elizium”). The tested combinations were fish farm wastewater, fish farm wastewater enriched with one of the three microbiological consortia, and fish farm wastewater supplemented with minerals. The best growth parameters of romaine lettuce plants were obtained in the combination of wastewater from fish farming supplemented with mineral nutrients. The application of fish farm wastewater and beneficial microbiological consortia positively influenced the fresh weight of lettuce leaves and the number of leaves per plant. However, plants fed with wastewater supplemented with minerals were characterized by the strongest symptoms of leaf tip-burn and the lowest commercial value. By comparison, plants fed only with fish farm wastewater or wastewater with microorganisms were characterized by a high, similar commercial value. After the application of increased doses of minerals, there was evidence of greater activity of microorganisms involved in nutrient cycling in aquaponic lettuce cultivation. The application of the microbiological consortia and minerals significantly increased the numbers and activity of the bacteria in the culture liquids 7, 14, and 21 days after inoculation.

Eating Sturgeon: An Endangered Delicacy

Since ancient times, sturgeon species have been valued for their rich nutritional qualities, which are crucial for human health today. They are linked with gastronomic delicacy and offer economic benefits, especially for the caviar industry. Today aquaculture produces more farmed and hybrid species due to rapidly declining wild sturgeon populations. Sturgeon diversification through processing can yield fingerlings, stocking material, meat or caviar. Because of its variety, sturgeon flesh includes highly digestible proteins, lipids, vitamins and minerals. Consuming sturgeon provides essential fatty acids that play important oxidative and anti-inflammatory roles in human cells. The purpose of this study is to examine the sustainability and economic value of eating sturgeon worldwide, the technology applied in food processing, and the challenges that food quality and authenticity, nutritional content and health effects pose. The issue of counterfeiting high-quality sturgeon products by dishonest means has to be adequately addressed. Digital tools to guarantee authenticity and transparency in the sturgeon value chain should be considered in the future.

Effects of sous vide cooking combined with ultrasound pretreatment on physicochemical properties and microbial communities of Russian sturgeon meat (Acipenser gueldenstaedti).

The production of Russian sturgeon is expanding rapidly in China but it is necessary to adopt measures to extend the shelf life of sturgeon meat. Previous studies found that sous vide cooking (SVC) at 60 °C increased the protein and lipid oxidation. The addition of antioxidant substances reduced the acceptance of the product. The effect of combination SVC and ultrasound pretreatment was therefore investigated. Results showed that SVC at 50 °C combined with ultrasound effectively restrained the growth of total viable counts (TVC) in samples. Meanwhile, the main dominant genera changed from Pseudomonas to Carnobacterium and the number of microbial species decreased. The odor profile of Russian sturgeon meat was more stable and the lipoxygenase (LOX) activity decreased more rapidly after treating with SVC and ultrasound. Importantly, more stable protein aggregates were formed in samples treated by SVC 50 °C together with ultrasound pretreatment, so the protein and lipid oxidation were slowed during storage. Higher springiness values were obtained and the color of sturgeon meat was lighter under these conditions. The combination of SVC 50 °C and ultrasound pretreatment effectively inhibited the microbial growth of Russian sturgeon meat at lower oxidation levels. These findings theoretically support the preservation and development of sturgeon meat, and the application of SVC technology. © 2022 Society of Chemical Industry.

Evaluation of Russian sturgeon (Acipenser gueldenstaedtii) Semen Quality and Semen Cryopreservation.

Simple SummaryThe decline in sturgeon populations, including Russian sturgeons, has reached alarming levels, threatening these species with extinction. The requirements for the meat of these fish, caviar and other products used in the textile, medical and food industries are constant or even on the rise. Reproductive biotechnologies seem to be the main solution to these problems, but the many unknowns related to the particularities of the species still place them far from the efficiency reached in some species of domestic animals. The development of fish farms for sturgeons and the intensification of reproductive biotechnologies is the main way in which the natural habitats affected by depopulation can be repopulated and to respond to the consumption and industrial requirements of the population. Our purpose is to contribute with additional novel information on the cryopreservation of sturgeon spermatozoa, as well as the evaluation of semen quality with the aim of developing a cryopreservation technique suitable for commercial breeding facilities.The alarming decline in sturgeon populations doubled by growing demands for sturgeon products, urge us to prevent the loss of these species. Fish stocking in natural habitats and developing fish farms are viable solutions, which can be successfully implemented with the help of reproductive biotechnologies. Despite the fact that semen cryopreservation is admittedly an important step for saving the Russian sturgeon, a reproducible standard method with good results has yet to be identified. Sperm quality assessment is essential for quantifying the impact of cryopreservation on spermatozoa. The purpose of our study was to provide additional information regarding semen cryopreservation and semen quality evaluation for the Russian sturgeon. Our study method is based on the use of two yolk-free extenders (with different cryoprotectants: DMSO and methanol) for freezing semen, using a simple freezing protocol. Parameters such as volume, concentration, motility, morphology and membrane integrity were evaluated. In conclusion, cryopreservation of Russian sturgeon spermatozoa using an extender containing methanol as cryoprotectant led to high egg fertilization percentages (72.67 ± 5.4%) even if the total motility values recorded for thawed semen were quite low (18–25%). Additionally, we identified two optimal stains for morphological studies and morphometry (Spermac stain kit and Trypan Blue Solution).

Effect of air fryer frying temperature on the quality attributes of sturgeon steak and comparison of its performance with traditional deep fat frying.

In this study, the influence of air‐frying temperature on the physical properties of sturgeon steaks was explored. Meanwhile, the comparison of traditional deep fat frying (TF) and air fryer frying (AFF) methods on the quality, flavor, and digestibility of sturgeon steaks were investigated. The results indicated that along with the increase of temperature (130, 160, and 190℃) for 15 min, the moisture content of AFF sturgeon steak surface decreased dramatically while that of interior was well preserved. The applied texture property analysis exhibited that AFF sturgeon steak showed the enhanced elasticity, low hardness, and soft texture. The results indicated that AFF sturgeon steak contained higher essential amino acid content than TF sturgeon steak. More flavor compounds (aldehydes, alcohols, and esters) were produced after AFF than TF. Although the digestibility of fried sturgeon steaks decreased after frying, AFF sturgeon steaks were digested rapidly in the stomach and intestine. Conclusively, AFF sturgeon steaks exhibited a crispy texture, appealing flavor, and low oil content. This work provides a certain reference for the suitable frying methods in the processing industry of sturgeon products.

Effects of Stocking Density on Growth Performance and Stress Responses of Bester and Bester ♀ × Beluga ♂ Juveniles in Recirculating Aquaculture Systems.

Simple SummaryThe disappearance of many wild sturgeon populations from natural waters and the high demand for sturgeon products (meat and caviar) have led to increased aquacultural production of sturgeons. The development of recirculating aquaculture systems requires the optimization of rearing technologies so that high stocking densities have a minimal impact on fish health. Due to the ease with which sturgeons hybridize, the optimization of sturgeon aquaculture technologies involves the identification of hybrid lines with high technological performance and high stress resistance. One of the best known hybrids is that between the beluga and the sterlet (bester). The present study aims to evaluate the hybrid obtained by crossing the bester (female) with the beluga (male) as a new candidate for the recirculating aquaculture systems. The results show better performance and better density adaptation of the bester × beluga hybrid compared with the bester hybrid. However, at higher stocking densities, a negative impact on growth performance and physiological response was observed.The study aimed to compare the growth performance and physiological responses of bester (B) and backcrossed bester ♀ × beluga ♂ (BB) in response to crowding stress under different stocking densities, as well as to establish a threshold stocking density for rearing BB in a recirculating aquaculture system (RAS) without welfare impairment. For this purpose, in the first trial (T1), B (181.15 ± 21.21 g) and BB fingerlings (181.98 ± 28.65 g) were reared in two stocking densities of 2 kg/m2 and 4 kg/m2 in fiberglass tanks (1 m3) for 6 weeks. In a parallel trial (T2), the BB hybrids (335.24 ± 39.30 g) were kept in four initial stocking densities, ranging from 5 kg/m2 to 12 kg/m2. The results of T1 revealed better growth indices (i.e., final mean weight, weight gain, specific growth rate) at lower stocking densities for both hybrids; however, in terms of growth performance, the BB hybrid showed better results when compared with the B hybrid. BB hybrids registered significantly (p < 0.05) lower serum cortisol and MDA and higher lysozyme than B hybrids, showing higher tolerance to crowding stress. Nevertheless, at higher densities, selected serum parameters (i.e., hematological indices, cortisol, glucose, protein, malondialdehyde, lysozyme) and growth performance indices used to evaluate the hybrids indicate that high stocking density could affect the growth and welfare of BB hybrids, and that the selected serum parameters could be used as good indicators for chronic stress caused by overcrowding conditions.

Influence of diet shift from bloodworm to formulated feed on growth performance, gut microbiota structure and function in early juvenile stages of hybrid sturgeon (Acipenser baerii × Acipenser schrenckii)

Currently sturgeon farming is one of the common cold fresh water farming in China, but its production is very low comparing with the country's cold water fish farming potential. One of the main reasons for the low production of sturgeon is unavailability of proper feed for early live stage of sturgeon. The aim of this study was to examine the effects of diet shift from live food (bloodworm) to formulated feed on growth performance, structure and function of gut microbiota in early juvenile stages of hybrid sturgeon (Acipenser baerii × Acipenser schrenckii). Significantly increased in weight gain rate (WGR) and feed conversion ratio (FCR) were observed in the sturgeon group fed on the formulated versus the bloodworm group (p < 0.05). Significantly higher Proteobacteria was recorded in the formulated feed group (p < 0.05), while Fusobacteria was significantly increased in the bloodworm group (p < 0.05). Furthermore, effects of colonization of the gut microbiota isolated from each group of sturgeon on host immunity was evaluated using germ free (GF) zebrafish model. The expression of genes related to anti-inflammatory (IL-10, TGF-β), non-specific immune (Lysozyme, C3a), and anti-virus (IFNΦ3, Mxb, Mxc) were significantly decreased in GF zebrafish colonized with gut microbiota of sturgeon fed on formulated feed, while expression of pro-inflammatory gene (TNFα) was significantly increased in formulated feed group. Moreover, GF zebrafish colonized with gut microbiota of sturgeon fed on the formulated feed revealed significantly lower survival rate for A. veronii Hm091 challenge (p < 0.05). In conclusion, the present study revealed that, compared with bloodworm, the formulated feed enhanced the WGR and FCR of sturgeon, but induced intestinal microbiota dysbiosis, which negatively affected the immune response of GF zebrafish and decreased their resistance to pathogenic bacteria.

Effects of ultrasonic, microwave, and combined ultrasonic-microwave pretreatments on the enzymatic hydrolysis process and protein hydrolysate properties obtained from Chinese sturgeon (Acipenser sinensis).

Degree of hydrolysis (DH), yield, amino acid profile, protein solubility, and antioxidant activity of Chinese sturgeon protein hydrolysates, as influenced by thermal pretreatment, ultrasonic (US), microwave (MW), and combined US-microwave pretreatments were investigated. Initially, the samples were subjected to thermal pretreatments in order to measure their effect on DH, which increased at 55°C. The DH recorded 7.63, 5.55, and 6.02% for US, MW, and combined US-MW pretreatment (US+MW), respectively, at the optimal time (8min). The enzymatic hydrolysis (EN) of pretreated samples increased the DH to 19.41, 14.18, and 16.91% for US+EN, MW+EN, and US+MW+EN, respectively. The US+EN treatment was most effective for obtaining higher DH and yield, which were 19.41% and 18.62%, respectively. The use of US+EN also resulted in an increase in the percentage of molecular weights (≤1,000Da), amino acid content and protein solubility, which reached 89.24, 80.08, and 98.58%, respectively. While, US+MW+EN pretreatment has achieved the highest antioxidant activities by IC50 of 1,1-diphenyl-2-picrylhydrazyl and 2,2-Azinobis (3-ehtylbenzothiazoli- 6-sulfnic acid), which were 3.01 and 1.85mg/ml, respectively, in addition to the reducing power assay, which was 0.528 at a protein concentration of 5mg/ml. Therefore, US and combined US-MW techniques can play a promising role in the production of protein hydrolysates and the improvement of their antioxidant properties. PRACTICAL APPLICATIONS: Nowadays, interest in Chinese sturgeon production has increased as a promising source of protein and antioxidant peptides. The optimal thermal pretreatment can be used to enhance the degree of hydrolysis. The results indicated that the use of ultrasound as a pretreatment enhanced the degree of hydrolysis, which could be useful in the preparation of protein hydrolysate with higher yields. The use of combined US-MW significantly improved the antioxidant properties of the protein hydrolysate. The combined US-MW technique is a novel method for obtaining valuable peptides and protein hydrolysates that can be applied as antioxidant constituents in the food products.

Larval lake sturgeon production and drift behaviour in the Menominee and Oconto Rivers, Wisconsin

AbstractLake sturgeon (Acipenser fulvescens) have been negatively impacted by barriers to migration, pollution and overharvest. Biological data such as the timing of spawning activity and larval drift have provided a better understanding of larval production success or failure on a site‐specific basis. However, many river systems that serve as reproductive locations for remnant lake sturgeon populations remain understudied. The objective of this study was to compare and contrast aspects of larval lake sturgeon drift within and between the Oconto and Menominee Rivers over multiple reproductive seasons. Differences in larval drift chronology, the size of drifting larvae during the season and the cross‐sectional profile of drifting individuals as a function of river velocity were evaluated. D‐frame drift nets were deployed at a single transect below spawning sites in the Menominee (2012, 2013 and 2014) and Oconto Rivers (2013, 2014 and 2015). A total of 4,442 larvae were captured across all seasons. Larvae exhibited nonrandom drift profiles related to water velocity, and larvae size was related to horizontal drift location. The seasonal increase in body size of drifting larvae also differed among drift events within and between years and across rivers. This information will provide a better understanding of lake sturgeon early life history and has practical management connections including spawning site protection/enhancement and river flow mitigation.

The Old and the New on Viral Diseases in Sturgeon.

Although sturgeon production by aquaculture has increased worldwide, a major factor limiting its expansion are infectious diseases, although few data about viral diseases are available however. This review provides a rapid overview of viral agents detected and described to date. Following a general introduction on viral diseases are four sections arranged by virus classification: sturgeon nucleocytoplasmic large DNA viruses, herpesviruses, white sturgeon adenovirus 1, and other viruses. Molecular diagnosis is currently the best tool to detect viral diseases, since cell culture isolation is not yet applicable for the detection of most sturgeon viruses.

Observations of carbon-nitrogen manipulation and periphyton growth stimulation on fish farming in an integrated intensive-extensive aquaculture system

Abstract The results of observations of intensive sturgeon production integrated with an extensive earthen fish pond are described. The main objective of the study was to show how technological modifications applied to enhance nitrogen assimilation in ponds and nutrient retention in aquaculture products influenced fish production. Each of two integrated systems, A and B, consisted of four intensive fish tanks stocked with sturgeon and one extensive carp pond stocked with carp (Cyprinus carpio L.), silver carp (Hypophthalmichthys molitrix (Val.)) and common nase (Chondrostoma nasus L.). The fish tanks were supplied with water from the extensive pond and the effluent from the tanks was discharged into the same pond, which acted as a biological filter for fish production. System B pond was supplemented with carbohydrates (methanol) and plastic substrates for periphyton development that were installed to increase nutrient utilization. The results of the observations showed better water quality and higher fish production in pond B, but no differences were noted in sturgeon growth performance in system A. The combination of these modifications appeared to be an efficient way of increasing nutrient retention and improving water quality.

The Involvement of Hormones in Fish: Basic and Applied Aspects of Russian Sturgeon (Acipenser Gueldenstaedtii)

Fish are a very large group, containing a huge variety of over 33,000 species.Scientific knowledge about the interaction between hormones of the somatic axis (SA) and the gonadotropic axis (GA), both of which function in the brain, and the pituitary gonad axis (BPG) that controls growth and reproduction, is vital for the domestication of fish in aquaculture.The Acipenserida family comprises 27 species, some of which have a very high economic value, among them Russian sturgeon (Acipenser gueldenstaedtii) that adapted to growth in aquaculture conditions. Many aspects aimed at improving the adaptation and production of Russian sturgeon (Acipenser gueldenstaedtii) have been studied for quite a long time. Models based on the results of our and others’ studies describing the interaction between GA and SA during oogenesis in Russian sturgeon have been suggested. The mRNA relative level of FSH during vitellogenesis (VTL) was higher in females than in males, affecting VTL secretion of vitellogenin (Vg); however, it was lower in the pre-vitellogenic stage than in VTL. No difference was found in mRNA levels of the luteinizing hormone (LH) in Russian sturgeon during the first four years of growth. During its first five years of growth, the level of GH mRNA was higher in females than in males, but due to the high standard deviation of the mean, the difference was not significant. IGF-I mRNA expression differed between the various tissues.

Masculinization of the gynogenetic juvenile ship sturgeon (Acipenser nudiventrisLovetsky, 1828) using 17α‐methyl testosterone

In sturgeons, the induction of gynogenesis and sex reversal could be important for potential production of neomale sturgeon and all-female progeny for caviar production. The aim of this study was sex reversal of ship sturgeon (Acipenser nudiventris Lovetsky, 1828) gynogen into male sex. Five-month-old gynogens were sex reversed into male by including 17α-methyl testosterone in their food for 7 months. Three treatments were considered as follows: (a) without treated (gynogen control), (b) 10 mg MT/kg diet, and (c) 50 mg MT/kg diet. All treatments (60 individuals) were sampled both the 30 and 36 months old and their sex was determined using classical histology method of gonad. The sex ratio of the progenies in the gynogen control were 73.3% female and 26.7% male. In treatment of 10 mg MT/kg feed, 18 specimens were studied that half of them (50%) showed pseudo-testicular structure in the female gonad. That is 50% of the specimens were intersex, 27.7% were male and 22.3% were female. All of the fish fed by 50 mg MT/kg feed had been sex reversed to male. Sexual maturation of these fish had been recognized in stage III at 36 months old. In conclusion, 50 mg MT/kg feed found as effective dose for successful sex reversal in gynogenetic ship sturgeon.

Molecular-genetic testing of freshwater species and breeds of animals (fish, narrow-clawed crayfish, mollusks)

Aim. Description of the results of molecular genetic studies of a number of fish, narrow-clawed crayfish, and mollusk species. Methods. For the analysis, RAPD, SSR, and DNA-barcoding methods were used. Results. Unique RAPD amplicones were identified to differentiate Lahvinsky, Tremlyansky and Isobelinsky carp breeds. With the use of SSR markers, the Dniester-Dnieper and Kama population belonging to the sterlet, grown in two farms of Belarus, was established. An instruction on the application of molecular genetic analysis to establish the species belonging to meat and caviar of sturgeon species was developed. The species composition and genetic polymorphism in narrow-clawed crayfish in reservoirs of Brest and Gomel regions was estimated. The work on DNA-barcoding of mollusks has begun. Conclusions. Molecular-genetic passports of carp breeds of Belarusian breeding are compiled. The population belonging to sterlet is determined in two fish farms inBelarus. Instruction for the use of molecular genetic analysis to establish the species (population) belonging to the sturgeon fish and their products is introduced in the country and used for testing and certification of sturgeon products. For the Byelorussian Polesie region, it is established that the narrow-clawed crayfish in theGomel region reservoirs has the greatest genetic diversity. Keywords: molecular markers, carp, sturgeon, narrow-clawed crayfish, mollusks.

Polyspermy produces viable haploid/diploid mosaics in sturgeon.

Most of sturgeon species (Acipenseridae) are currently critically endangered. Attempts to revive these populations include artificial breeding in hatcheries. However, under artificial reproduction, sturgeon embryos occasionally develop atypically, showing 3, 5, 6, 7, 9, or 10 cells at the 2- to 4-cell stage. This study was undertaken with the objective of understanding the mechanism of the atypical division (AD) in embryos during artificial breeding. Using several sturgeon species, we tested two hypotheses: (1) polyspermy and (2) retention of the second polar body. We found that (1) AD embryos survive similar to controls, (2) the ratio of AD embryos is positively correlated with the amount of sperm used for fertilization, (3) the number of micropyles and the area covered by them in AD embryos is significantly greater when compared to controls, (4) numerous spermatozoa nuclei are in the cytoplasm after fertilization, (5) all AD embryos are mosaics, and (6) AD fishes with n/2n ploidy contain diploid cells from maternal and paternal genetic markers, while the haploid cells contained only paternal ones. These results clearly indicate that AD embryos arise from plasmogamy where the accessory spermatozoon/spermatozoa entry the egg and develop jointly with zygotic cells. This suggests that a well-controlled fertilization procedure is needed to prevent the production of sturgeon with irregular ploidy, which can have detrimental genetic effects on sturgeon populations. On the other hand, if AD fish can produce haploid-derived clonal gametes, induction of multiple-sperm mosaicism might be a useful tool for the rapid production of isogenic strains of sturgeons.

Mitochondrial DNA genetic diversity in the wild and two cultured Kaluga ( Huso dauricus ) populations in China

PDF HTML阅读 XML下载 导出引用 引用提醒 中国达氏鳇野生群体和两个养殖群体的线粒体遗传多样性分析 DOI: 作者: 作者单位: 1. 中国水产科学研究院黑龙江水产研究所, 黑龙江省冷水性鱼类种质资源及增养殖重点开放实验室, 黑龙江 哈尔滨 150070;2. 中国水产科学研究院黄海水产研究所, 山东 青岛 266071 作者简介: 户国(1984-),博士,副研究员,主要研究方向为分子数量遗传与水产动物育种.E-mail:huguo@126.com 通讯作者: 中图分类号: S917 基金项目: 国家科技重大专项子课题（2015ZX07201-008-05）；中国水产科学研究院基本科研业务费专项（2014A11）. Mitochondrial DNA genetic diversity in the wild and two cultured Kaluga (Huso dauricus) populations in China Author: Affiliation: 1. Heilongjiang Province Cold-Water Fish Germplasm Resources and Aquaculture Key Laboratory, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China;2. Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao 266071, China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:达氏鳇（基因和D-loop区域的多态性信息评估了黑龙江抚远段野生群体、北京房山国家级鲟鱼原种场的保种群体及浙江衢州国家级鲟鱼良种场的繁殖群体等3个达氏鳇群体的遗传多样性水平。所有测试个体在Cyt 单倍型，而在D-loop区域中发现了9种单倍型，对于D-loop区，单倍型多样性（）仅为0.00213。在8尾野生个体中检测到6种D-loop单倍型，2个养殖群体共计58尾个体共计检出5种D-loop单倍型个体。分析结果显示：野生达氏鳇群体遗传多样性极低，历史上可能经历过严重的遗传瓶颈，同时达氏鳇人工繁殖过程中每批次可能只有极少个体参与了繁殖。此外，基于Cyt Huso）的分类地位得不到有效的分子生物学数据支持。 Abstract:Kaluga () is the native sturgeon in the Amur river. Similar to other sturgeons, their populations have sharply decreased in recent decades; they have been identified as one of the most endangered species in the world. Unlike the rapid decline of wild populations, sturgeon farming has rapidly increased in China Mainland. The intra-specific hybridization of the female Kaluga and male Amur sturgeon () is widely performed, constituting a large part of sturgeon production in China. In this study, we use the Cyt gene and D-loop region of mitochondrial DNA to assess the genetic diversity of three Kaluga populations, including the wild population from the Amur river, and two populations cultured in national sturgeon breeding farms located in China:one from Fangshan, in Beijing city and the other from Quzhou, in the Zhejiang province. All of the tested individuals were of identical the Cyt haplotype, whereas 9 haplotypes were found in the D-loop region. There was no diversity detected at the nucleotide level on the Cyt d) reached 0.593, but nucleotide diversity () was only 0.00213. There were 6 D-loop haplotypes detected in 8 individuals from the wild population and 5 haplotypes detected in 58 individuals from the cultured populations. The results suggested the wild Kaluga population might have experienced a serious genetic bottleneck. Meanwhile, in the process of artificial propagation of Kaluga, only a few individuals might have been involved in reproduction each time in both the cultured populations. Phylogenetic tree analysis based on partial sequences of the Cyt genes supported the previous results from other researchers. The phylogenetic relationship between and other Pacific sturgeon species was close, but that between was not. Our result implied that the prevalence of the traditional genus was not supported by molecular genetic data. 参考文献 相似文献 引证文献