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In Cameroon, wild strains of Clarias gariepinus (Burchell, 1822) are often used for artificial reproduction in hatchery facilities, but there is insufficient information on their reproductive capacity and progeny performance. The reproductive capacity of two strains of C. gariepinus from the Mezam and Mungo Rivers and the performance of their F1 larvae obtained following hybridization were assessed. Reproduction was carried out with four crosses as follows: Mezam (♂) x Mezam (♀) (T1), Mezam (♂) x Mungo (♀) (T2), Mungo (♂) x Mezam (♀) (T3) and Mungo (♂) x Mungo (♀) (T4). Thereafter, three days old larvae obtained following reproduction were subjected to a 30 day experimental trial with standard feeds. The performance of larvae obtained from T4 was not assessed since larvae obtained were too few for the experiment. Although the broodstock of the different strains did not differ significantly in size, Mezam stock had significantly (p = 0.00) bigger eggs when compared to Mungo stock. Fecundity of 52480 was recorded for Mezam stock compared to 32985 for Mungo stock. Fertilization and hatchability rates differed significantly (p < 0.05) among the crosses, with the highest (82.28 and 81.31%, respectively) in T1, followed by T3 (65.96 and 61.28%, respectively), and the least (38.61 and 2.81%, respectively) in T4. The best larval survival was recorded in T1 (37.17%) and the least in T2 (15.67%), meanwhile T3 recorded best growth after 30 days. In terms of fertilization and hatchability, T1 was more suitable for artificial reproduction, but T3 is more encouraged for aquaculture based on its reproductive capacity and larval performance.

Information on the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) has amplified quickly since its spread; however, many issues remain unclear. SARS-CoV-2 is mainly transmitted through respiratory secretions. However, the potential for SARS-CoV-2 sexual transmission by semen is worthy of study. The cell-receptors of SARS-CoV-2, the angiotensin-converting enzyme-2 receptors, are highly expressed in human testis and may enable this virus to cause testicular tissue damage with bad effect on male fertility. SARS-CoV-2 presentation ranges from asymptomatic carriage to acute respiratory distress and fatal pneumonia, and elderly persons with underlying comorbidities usually suffer from a severe clinical picture. Asymptomatic individuals can spread the virus through their respiratory secretions and possibly through sexual transmission. SARS-CoV-2 can persist viable if cryopreserved in semen samples in sperm cryobankes. As far as I know, there is a gap in knowledge about SARS-CoV-2 transmission through semen, indicating the need for further research. This review attempts to understand the SARS-CoV-2 sexual transmission by semen. One recent study confirmed the theoretical risk of SARS-CoV-2 transmission by semen, but few studies negate this theory. Given that, an increasing number of asymptomatic and reactivated SARS-CoV-2 cases are being reported, attention to semen safety and SARS-CoV-2 transmission should be considered particularly in high-risk areas, to ensure the safety of male gametes for artificial reproduction and the general public. Avoiding cryopreservation of male gametes, condom use or even abstinence might be of paramount importance for these persons.

The water temperature of the tanks of the breeding herds exerts a strong influence on the process of artificial reproduction. Its monitoring through the hour-degree, serves to assist in the moment to be made the extrusion of the oocytes. The objective was to monitor the time-degree that Colossoma macropomum females need after the second dose of the hormonal induction protocol, until the time of extrusion of their oocytes. The analysis was carried out at the Fish Fishery in the municipality of Sorriso-MT. Nine breeding women were submitted to the protocol of hormonal induction with pituitary extract of carp being administered in two doses. In the former, the dose of 0.5 mg / kg was used and the second dose was 5 mg / kg body weight, with an interval of 12 hours. From the second dose, the temperature in degrees centigrade of the water from the tanks was monitored hourly until the time of oocyte extrusion. Breeders had muscle tremors, swimming in circles, and were more agitated nine hours after the second dose. The oocytes had a yellowish-brown appearance, and some had individual features. The sum of the temperature of the water in hours-degree obtained was of 243. The temperature of the water did not present variation, maintaining itself at 27 ° C. It is concluded that an hour-degree is necessary for an extrusion of oocytes in some of the things you can find in Colossoma Macropomum of 243, agreeing with the limits proposed in the literature.

In most animals, males produce large numbers of sperm in each ejaculate, but only very few end up fertilising an egg. This bottleneck in sperm numbers from ejaculation to fertilisation offers an intuitive opportunity for selection to act and improve the fitness of the next generation. However, the general view that sperm phenotype is not linked to its haploid sperm genotype stalled further research into this idea until recently. Two studies in zebrafish Danio rerio now suggest that selection among sperm within the ejaculate of male may have far-reaching consequences for the following generation(s). Selection for longer lived sperm resulted in offspring that showed higher survival during embryo development and a reduced number of abnormally developed larvae, as well as increased reproductive success during adulthood. These effects have been linked to the haploid genotypes in the sperm. We here discuss the possible benefits of refined sperm selection based on sperm haplotypes in the use of artificial reproduction technologies. Understanding the genetic processes occurring after meiosis until syngamy may provide insights that may help improve the existing methods and with that their success rates.

One of the major problems in artificial eel reproduction is identification of broodstock with high performance reproductive characteristics. The aim of this study was to study population characteristics and the reproductive potential of eels (Anguilla anguilla) located in Valle Campo valley (Comacchio, Italy). A total of 200 eels/period (spring–summer and autumn–winter) were measured to obtain an external indicator of their maturation state. Morphometric parameters were used to calculate condition factor (K), eye index (EI) and pectoral fin length index (PFLI). Silver index analyses showed the lack of silver males and of fully mature females. Most represented females were yellow females at stage II. Silver females represented 27.9% of the population. Seasonal analysis shows how temperature reduction favoured the presence of silver females versus yellow females. Statistical analysis of EI, cranial (CI), PFLI and gonadosomatic (GSI) indexes showed that significant differences were found for EI, CI, PFLI and GSI between yellow and silver eels. No significant difference was found between stage III and IV silver eels, while a significant difference for EI was found between stage I and II yellow eels and for IC at stage II with respect to all other stages. The present study defined how Valle Campo could present environmental and trophic conditions which could favour precocious development of a population of silver females with a noticeable reproductive potential, to be used in open sea release or in artificial reproduction programmes. On the contrary, the valley seems to present unfavourable conditions for both development and sexual maturation of male eels.

Silver carp, Hypophthalmichtys molitrix (Cyprinidae), is the most important freshwater fish in Algerian aquaculture. No natural spawning is observed in Algerian water bodies. This study was conducted with the aim of investigating silver carp reproduction in the wild in Algeria. This investigation can contribute tools to facilitate successful artificial reproduction. Macroscopic and histological analysis of the gonads was conducted, and the monthly distribution of maturity stages and oocyte diameters were monitored in an aggregate sample of 130 male and female silver carp, H. molitrix, (450-710 mm total length). The gonadosomatic index (GSI) ranged from 2.76 to 18.88% in females and from 0.34 to 1.85% in males. The female GSI values were the highest from June to August indicating the onset of the spawning season. The histological structures of the gonads revealed five different developmental stages in females and three stages in males. The oogenesis stages were the perinucleolar stage, the yolk vesicle stage, the primary yolk, the secondary yolk, and the tertiary yolk. Migratory nuclei and hydrated oocytes, which are considered to be the maturation stage, were not observed. Three different spermatogenesis phases (immature, maturing, and mature testis) were identified, which included final spermatozoa maturation.

Aquaculture of red swamp crayfish, Procambarus clarkii (Girard, 1852), has developed rapidly worldwide in recent years with promising prospects. However, limited knowledge about temperature effects on reproductive performance and embryonic development has hindered the development of crayfish aquaculture. The two present studies were conducted to identify optimal water temperatures (17 °C, 21 °C, 25 °C, 29 °C and 33 °C) for reproductive performance (experiment 1) and embryonic development (experiment 2) of P. clarkii. Totally, there were 12 replicates, with 480 adults and embryos from 60 ovigerous crayfish selected for experiment 1 and 2, respectively. In the first experiment, the survival of adult crayfish was not significantly affected by the temperatures tested. However, significantly higher feeding rates, spawning rates, and fecundity were obtained at 21 °C and 25 °C when compared to those at 29 °C and 33 °C. Polynomial models and loess regression fitted to the experimental data showed that highest spawning rates and fecundity occurred at 21 °C while shortest duration from mating to spawning was found at 33 °C. In the second experiment, we found that optimal embryonic development was at 25 °C with shorter hatching time and no abnormalities observed. However, while embryos showed abnormalities and subsequently died at 29 °C and 33 °C. We further built a temperature-dependent developmental model for P. clarkii embryos: D (developmental time, days) = 3,140,837(T-2.03)−3.76. Based on these results, the temperature range 21 °C – 25 °C was recommended for adult crayfish reproduction and 25 °C was recommended for embryonic development. This study indicates that manipulating water temperature is an effective alternative to current artificial reproduction techniques (e.g. eyestalk ablation and injection hormones) to induce spawning and embryonic development and thus provides mass production of juvenile P. clarkii for aquaculture.

This study investigated physiological and behavioral responses of pikeperch broodstock related to sexual interactions under controlled conditions throughout semi-artificial reproduction. Blood samples taken from pond-cultured pikeperch broodstock were analyzed to assess the stress response at different stages of semi-artificial reproduction protocol. Sampling was performed as follows: before hormonal induction (control), 24 h (SP24) and 48 h (SP48) after spawning when males and females were separated, and 24 h (NS24) and 48 h (NS48) after spawning when males and females were kept together. The separation immediately after spawning had a significant effect on physiological state of broodstock. Separation affected indices of erythrocyte count, hematocrit (packed cell volume, PCV), glucose (GLU), and mean corpuscular volume (MCV) in females and levels of lactate and leukocytes in males. Monitoring of pikeperch behavior in groups NS24 and NS48 revealed the strong aggressive paternal behavior of male to females. Attacks mainly targeted the caudal fin and resulted in female mortality in group NS48.

Orestias ascotanensis Parenti is a critically-endangered fish species endemic to the Ascotan salt pan springs. Given the importance of reproduction and early development in effective conservation of fish populations, this study describes the embryonic development of O. ascotanensis under laboratory conditions. Between 2014 and 2015, 50 individuals were captured and maintained under controlled conditions, including temperature, photoperiod and feeding regimen, to induce spawning for artificial fertilization. Females were subjected to hormone therapy with Ovaprim®. Water temperature was maintained at 20 °C (± 1 °C), conductivity at 2800–3600 μS·cm−1 and photoperiod at 16:8 (light hours: dark hours). Males showed changes in color and courtship behavior, and females developed a slightly bulging belly. Eggs were 1.55–2.5 mm in diameter, with abundant yolk and dozens of adhesion filaments. Embryonic development lasted 14–18 days; it was divided into five periods, which can be sub-divided into 21 stages, from fertilization to hatching. O. ascotanensis showed indications of partial spawning species, including oocytes at different stages of development, relatively large eggs as compared to adult fish length and low batch spawning. Characteristics such as partial spawning, highly-pigmented eggs and larvae and advanced larval development at hatching could be adaptations to the extreme conditions of the salt pan springs, including high levels of ultraviolet radiation and salinity as well as significant daily temperature changes.

Procuring offspring from captive animals can be important for research and conservation efforts. Yet, reliable methods for obtaining fertilised eggs are unavailable for many species. In this study, we examined the efficacy of one drug, leuprolide acetate, to induce reproduction (i.e. egg production, tadpole hatching) in the northern leopard frog, Rana pipiens. We found that leuprolide acetate successfully induced breeding and larval development in animals that were overwintered in the lab, but not in animals caught during the breeding season. These results indicate that leuprolide acetate can be successful in inducing breeding and fertilisation of frog eggs, but that its effectiveness might be contingent upon length of time in captivity and the animals having undergone an artificial overwintering period in the laboratory prior to induction. Artificial breeding success is species and context dependent; therefore, identifying additional methods effective across taxa will help support species in need of management intervention.

Pinctada martensii is one of several important pearl oysters. Ammonia is typically added to the seawater and used during artificial reproduction to improve the fertilization rate. However, the optimal ammonia concentration has not been determined. To determine the optimal ammonia concentration for fertilization success, the effect of the ammonia concentration on the fertilization rate in P. martensii was investigated under the simultaneous influence of temperature and salinity. A Box-Behnken design and response surface method were used in this study. The results showed that the ammonia concentration had a significant effect, which varied quadratically with the ammonia concentration in the ranges of the factor regimes (P

This study focused on the artificial reproduction of common dace Leuciscus leuciscus (L.) outside the reproductive season. The results indicate there is the possibility of initiating the reproducion in individuals of this before the natural spawning season. There could be induction of spermiation by altering the environmental conditions. For females, hormonal injections were necessary for induction of final oocyte maturation and ovulation. Generally, there were high percentages of spermiation (100%) and ovulation (87%–100%) as well as low mortality (0%–11% and 7%–13% for males and females, respectively) among the induced spawners. The greatest embryo survival occurred when Ovaprim (84.4%) or hCG (89.6%) was administered, although the latency time using hCG was at least twice as long compared to when other spawning agents were used (84–92 hrs and 30–44 hrs). The results from present study could be applicable for optimization of breeding stock numbers in aquaculture enterprises and in providing insights for conservation of L. leuciscus endangered populations.

Simple Summary Quite severe biological imbalances have been caused by the often ill-conceived and destructive actions of humans. The natural environment, with its flora and fauna, has been subjected to a strong, direct or indirect, anthropogenic impact. In consequence, the total population of wild animals has been considerably reduced, despite efforts to compensate for these errors and expand the scope of animal legal protection to include endangered species. Many animal populations on the verge of extinction have been saved. These actions are ongoing and embrace endangered species as well as those which may be threatened with extinction in the near future as a result of climate change. The changes affect economically valuable species and those of low value, whose populations are still relatively strong and stable. Pre-emptive protective actions and developing methods for the reproduction and rearing of rare species may ensure their survival when the ecological balance is upset. The blue bream is one such species which should be protected while there is still time. Abstract The blue bream Ballerus ballerus (L.) is one of two species of the Ballerus genus occurring in Europe. The biotechnology for its reproduction under controlled conditions needs to be developed to conserve its local populations. Therefore, a range of experiments were performed to obtain valuable gametes from blue bream following hormonal stimulation with carp pituitary homogenate (CPH), Ovopel and Ovaprim. CPH and Ovopel were injected twice and Ovaprim—once, under a pectoral fin. The spawners were inspected 12 h after the last injection, and the gametes were collected. Eggs were collected from spawning females and fertilized with sperm from three males. The smallest number of ovulating blue bream (four females) was obtained from individuals stimulated with Ovaprim. There were six to nine ovulating females in the other groups, accounting for 60–90% of the females in the respective groups. The latency period was the shortest in the spawners stimulated with Ovopel. The fish in this group ovulated 14 h after the hormonal injection. Spawning was synchronized and all females spawned simultaneously. The highest average weight of eggs per fish (75.4 g) was obtained from the females stimulated with Ovopel, whereas the individuals stimulated with Ovaprim provided the smallest average amount of eggs (49.5 g). The study showed that blue bream spawners are not very sensitive to reproduction-related handling under controlled conditions.

Optimization of artificial reproduction is essential for minimizing genetic diversity, especially when fish are captured from their natural habitats and spawned in controlled conditions. In the present study, there was evaluation of the effects of gonadotropin-releasing hormone analogue (GnRHa) and human chorionic gonadotropin (hCG) with or without dopamine receptor antagonists such as domperidone (DOM) and metoclopramide (MET) on the spawning efficiency of African catfish (Clarias gariepinus) reared in captivity. The control group was intramuscularly (IM) injected with 1 mL of sterile saline solution. The fish specimens of the other six groups were injected IM with GnRHa or hCG, or in combination with either DOM or MET. None of the specimens had ovulations in the control group. There was the longest latency period in specimens treated with only GnRHa or hCG. There were the largest egg mass weight, fecundity, and hatchability (%) in specimens of the GnRHa + MET group. These findings indicate that GnRHa or hCG combined with dopamine receptor antagonists such as DOM and MET resulted in a marked enhancement of ovulation rate and increased the egg mass, fecundity, and hatchability of the treated C. gariepinus, and the values when there was inclusion of the MET treatment exceeded those when there was treatment with DOM.

The use of recombinant gonadotropin-releasing hormone (rGnRH) has very rarely been tested in fish to promote spawning. This study evaluated the impact of recombinant chicken gonadotropin-releasing hormone (rcGnRH) with metoclopramide on the release of sex steroids and final maturation induction in goldfish (Carassius auratus) broodstock. For this purpose, goldfish broodstock was divided into four groups and treated with 0.9% NaCl with 20 mg/kg metoclopramide (Met) (C); 10 μg/kg body weight (BW) rcGnRH with 20 mg/kg metoclopramide (rcGn10); 15 μg/kg BW rcGnRH with 20 mg/kg metoclopramide (rcGn15); and 20 μg/kg BW rcGnRH with 20 mg/kg metoclopramide (rcGn20). The capability of the rcGnRH for eliciting biological response was tested in vivo by evaluating the changes of 17β estradiol (E2), testosterone (T), and 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) and the induced spawning. Blood samples were obtained at 0 h, 12 h, and 24 h after injection. The rcGn10, rcGn15, and rcGn20 treatments induced lower E2 concentration, especially 24 h post-injection. T levels were significantly higher in rcGn10, rcGn15, and rcGn20 treatments 12 h post-injection than at 0 h and then decreased at 24 h post-injection. Furthermore, the rcGnRH tested significantly enhanced DHP secretion in rcGn10, rcGn15, and rcGn20 treatments 12 h post-injection before a decline at 24 h post-injection. No significant difference between the sampling times was found in the C treatment for the 3 sex steroids tested. The results also displayed that rcGnRH at 10–20 µg/kg of body weight can trigger spawning with the highest speed and efficiency of spawning at 20 µg/kg. The obtained results represent a possible strategy for enhancing the artificial reproduction and ovulation of broodstock fish by rGnRH and further support the use of recombinant hormones to promote reproduction in aquaculture.

In the early 80-ies of the last century, there was a sharp decline in the population of the Caspian beluga in Russia. Its fishing was prohibited, except for catching for reproduction and scientific purposes. In the practice of sturgeon breeding, the method of repeated use of sturgeon females and males by obtaining sexual products in vivo, as well as growing breeders in artificial conditions, has become widely put into practice. Against the background of an acute shortage of wild breeders of this sturgeon species, in recent years, the main way to form sturgeon broodstock in the conditions of the Lower Volga region is domestication. However, in recent years, the catches of wild beluga females in the fishing areas of the Lower Volga are estimated as single specimens. The article studies the fish-breeding, biological and physiological parameters of domesticated and aquaculture-bred beluga females. The reproductive function of domesticated and artificially raised beluga females is evaluated. Some proposals for the intensification and priority areas of artificial reproduction in order to replenish natural populations are presented.

Sperm sorting and analysis are essential for artificial reproductive methods in animals and humans. Sperm characteristics such as viability, motility, kinetic parameters, and morphology are notable parameters for evaluation of semen samples. Isolation of defective spermatozoa and unwanted cell debris from cell samples was correlated with high fertility rates. Sperm analysis before the use of semen in artificial reproduction is critical and helps to increase the success rate. Conventional methods of sperm sorting are associated with either low efficiency or high cost. Reliability and reproducibility are the major drawbacks of conventional methods which are still in use. Mechanical damage is also one of the problems of conventional and commercial strategies of cell sorting. Computer-assisted sperm analysis (CASA) is the most reliable sperm analysis method, and its use is limited due to its high cost.

Pikeperch (Sander lucioperca) is a species of significant importance for the further development of intensive aquaculture, what makes the total control over species’ reproductive cycle a high priority task. The present study aimed to assess the effect of arachidonic acid (AA) dietary enrichment on the reproductive performance in virgin females (two-years-old; individual weight 1.0 ± 0.2 kg) kept in fully controlled conditions with respect to different time of hormonal application. Two groups of breeders, ARA (fed AA enriched diet) and CTRL (fed control feed), were reared in two separated tanks of the recirculation system over the course of seven months. Five, six, and seven months after the start of trial, batches of five pairs of breeders (in total 15 pairs per each feeding group) from each group were hormonally treated. Ovulations occurred after six and seven months (oocyte diameter range 912−1030 μm), and samples of dry eggs were taken for the analysis of fatty acid profiles. Among the parameters of reproductive success, the embryo survival was significantly affected by the diet, while induction duration affected latency time only. The CTRL group females showed overall higher embryo survival across both reproduction occasions (p = 0.028) than group fed AA enriched diet (35.7 ± 17.1 % and 18.6 ± 13.6 % in CTRL and ARA group, respectively). A significant accumulation of AA was found in ARA group eggs in both reproduction batches. Virgin pikeperch breeders appear to keep at least one month plasticity towards the duration of spawning induction in controlled conditions and optimal oocyte diameter range for artificial reproduction is between 900−1000 μm. Levelling dietary AA with eicosapentaenoic acid during the entire photothermal protocol negatively altered the egg quality.

International audience; In the present study, the biological function of recombinant gonadotropin-releasing hormone associate peptide (rGnRH) was tested for the induction of ovulation and spawning in Sterlet sturgeon (Acipenser ruthenus) broodstock. For this purpose, Sterlet sturgeon broodstock were divided into four treatments and treated with following preparing procedure: 0.9% NaCl (C); 2.5 mu g kg body weight(-1) (BW) LHRH-A2 (luteinizing hormone-releasing hormone-A2, L2.5); 2.5 mu g kg BW-1 rGnRH (rGn2.5); 10 mu g kg BW-1 rGnRH (rGn10). The capability of the rGnRH for eliciting biological response was studied in vivo by evaluating the changes of 17 beta estradiol (E2), progesterone (P) and testosterone (T) and by its ability for inducing final maturation. Blood samples were collected at the time of first injection, 10 h after the first injection and at ovulation time. The L2.5 or rGn10 treatments led to significantly lower E2 concentration 10 h after the first injection and at ovulation time compared to the baseline measures. E2 levels increased in the rGn2.5 treatment 10 h after the first injection and by ovulation time compared to the time of first injection. T levels were significantly increased in the L2.5 or rGn10 treatments 10 h after the first injection compared to the time of first injection and it further decreased at ovulation time. No significant differences were found in C and rGn2.5 treatments between the different sampling times. P secretion was significantly higher in the rGn10 or L2.5 treatments compared to C and rGn2.5 treatments 10 h after the first injection and at ovulation time. No significant difference was found in P secretion in the C and rGn2.5 treatments at different sampling times. The results showed that the rGnRH at the highest dose (10 mu g kg BW-1) was more efficient than the other treatments in the induction of spawning and this dose caused P secretion and spawning in vivo. Our results present the possibility of using rGnRH in artificial reproduction of sturgeons and it can be introduced as a specific homologue to treat reproductive disorders in fish.Highlights: 1. rGnRH had a positive effect in final maturation in Sterlet sturgeon. 2. rGnRH at the dose of 10 µg kg body weight-1 was efficient in spawning induction. 3. rGnRH can stimulate the secretion of sex-steroids in vivo. 4. rGnRH can be used as a specific homologue to treat reproductive disorders in fish.

Although ruffe (Gymnocephalus cernua) are widely distributed in Eurasia, in some regions (i.e., North America) ruffe are considered an invasive species. There have been no reports on artificial reproduction of this species. A study, therefore, was conducted to evaluate reproduction of ruffe with results of specimens captured from their natural habitat and cultured (F1 generation) specimens being compared. Spawning specimens from both stocks were treated with hormonal preparations: carp pituitary homogenate (CPH), Ovopel, Ovaprim and human chorionic gonadotropin (hCG) and results were analyzed by comparing response to the specimens of control groups. Spermiation outcomes and sperm motility of the captured and cultured ruffe were similar and with all hormonal treatments, there was a slightly greater sperm motility (55.6 %–57.1 %) in comparison to specimens of control groups (46.7 %–47.1 %). For captured specimens, there was no asynchronous development of oocytes, whereas in cultured specimens 32 % of females had asynchronous development of oocytes. The ovulation rate in specimens of all treated groups was 100 %, whereas specimens in the control groups did not reproductively mature and have ovulations. The latency time from time of hormonal treatments to initiation of reproductive functions depended on the spawning agent used and oocyte maturation stage and there was the shortest latency after using CPH and the longest with hCG treatment. The embryo survival and hatching rates varied with use of different hormonal preparations to induce reproduction: greatest hatching rates with hCG treatment (86.4 %–88.9 %), followed by Ovaprim (78.2 %–80.2 %) and least hatching rate with Ovopel and CPH treatments (66.0 %–67.1 % and 64.0 %–66.0 %, respectively).

Fertilization is one of the most important procedures in artificial reproduction and it directly affects the reproduction outcome. When there is optimization of fertilization, there can be a positive effect on subsequent reproductive processes and economic aspects of aquaculture. This study was conducted to determine time for which oocytes and sperm of barbel Barbus barbus retain fertilization capacity following placement in freshwater. Furthermore, the amount of ovarian fluid, excreted by fish during spawning with eggs (OFI; %) was determined, along with the chemical composition and effects on fertilization were determined. Gametes, ovarian fluid, and seminal plasma from barbel spawning specimens of the F4 generation were used to conduct the study. Ovarian fluid accounted for 14%–68% of contents of the mass released at spawning and post-spawning composition differed depending on whether hormonal treatments were utilized for control of reproduction. There was an association (R2 = 0.982; P = 0.000) between the pH of ovarian fluid and the barbel embryo survival rate. There was the greatest survival rate (>60 %) when the pH range of 7.9–8.4 and there was a lesser embryo viability when pH values were lesser or greater than values within this range (P

An alarming number of large mammalian species with low reproduction rates is threatened with extinction. As basic knowledge of reproductive physiology is currently lacking in many species, increasing the understanding of reproductive physiology is imperative and includes the development of novel artificial reproduction technologies. Despite the relatively comprehensive knowledge on molecular mechanisms underlying reproduction in livestock species such as cattle, pregnancy failures are likewise far from understood. Contrary to other wildlife species, the European roe deer (Capreolus capreolus) displays a remarkably high pregnancy rate. In parts, cattle and roe deer exhibit comparable features of preimplantation embryo development. Therefore, understanding the high fertility rate in the roe deer holds a great potential for cross-species knowledge gain. As the only known species among the artiodactylae, the roe deer displays a long period of embryonic diapause. The preimplantation blastocyst reaches a diameter of 1 mm only at around 4 months compared to around 13 days post estrus in cattle. The expanded blastocyst survives in a uterine microenvironment that contains a unique set of yet unidentified factors that allow embryonic stem cells to proliferate at low pace without impairing their developmental potential. Upon reactivation, intimate embryo-maternal communication comparable to those reported in cattle is thought to occur. In this review, current knowledge, parallels and differences of reproductive physiology in cattle and roe deer are reviewed. The roe deer is proposed as a unique model species to (1) enhance our knowledge of fertility processes, (2) define factors that support embryo survival for an extended period, (3) advance knowledge on embryonic stem cells, and (4) unravel potential implications for the development of novel strategies for artificial reproductive technologies.

Optimization of artificial reproduction, by increasing the survival rate of embryos and hatching rate, is of major importance for reducing genetic diversity, especially in fish captured from their natural habitat that subsequently spawn in hatcheries. The artificial reproduction of ide, Leuciscus idus (L.) was conducted in controlled conditions. The spawning agents included: different doses of human chorionic gonadotropin (hCG) that was compared with common carp pituitary homogenate (CPH), Ovopel – a commercial agent for induction of spawning that contains mammalian gonadotropin releasing hormone analogue (mGnRHa) with dopamine antagonists (DA): metoclopramide (MET) and Ovaprim – a commercial agent containing salmon gonadotropin releasing hormone analogue (sGnRHa) and a dopamine antagonists (DA): domperidone (DOM). There were no ovulations in females from control groups. There were no differences between the ovulation rates (90 %) or embryo survival (> 92 %) and hatching rates (> 91 %) when there was administration of hCG doses between 500 and 1000 IU/kg. When there was comparison of different spawning agents, the ovulation rate was 100 % for all treated groups. There were the shortest and longest latency times to the time of ovulation after administration of CPH (26 h) and hCG (79 h), respectively. The greatest embryo survival (> 93 %) and hatching (> 91 %) rates occurred as a result of hCG administration with these values being slightly greater than when there was treatment with Ovaprim. The association between latency time and hatching rate indicated that when there was a slower final oocyte maturation (FOM) there were greater hatching rates.

European eel Anguilla anguilla is among the highly valued species for aquaculture. Since its peculiar biology, it is not yet possible to complete the whole life cycle in artificial conditions and its supply depends entirely on wild catches. In the last 50 years this species has suffered a population reduction of 99 % mainly due to overfishing. In a conservation perspective, it is of fundamental importance to improve the aquaculture production of European eel, to avoid the extinction of this species and preserve its residual genetic variability, allowing at the same time the fulfilling of costumers request without increasing its harvesting pressure.In this study we aimed to deepen the knowledge about the mechanisms at the basis of reproduction of the European eel in semi-natural conditions, through direct observation of spawning behaviour and through the paternity assignment using microsatellite markers. The systematic and prolonged observation of the reproductive behaviour of European eel and the contextual parentage analyses we carried out for the very first time in this species on 39 adults and 432 F1 randomly collected. We contributed to unravel the sexual behaviour of this species in the most common artificial reproduction conditions (polyandry), and define the precise courtship sequence until the release of gametes, and the male-male hierarchy in courtship. We characterized for the first time three main types of male: dominant (the first who starts the courtship, and the one with the majority of F1 assigned), subordinate (which starts the courtship only in a second time and with a minor percentage of F1 ascribed) and ineffective (which sometime appears totally disinterested to courtship and has few F1 or none).The evidences here produced represent an important attempt for developing good reproduction practices of the critically endangered European eel, providing a good starting point for its future aquaculture production. Keywords: Anguilla anguilla, Aquaculture, Artificial breeding, Kinship analysis, Parentage assignment

Simple Summary This paper describes a technique of pneumatic stripping of whitefish (Coregonus lavaretus) eggs with the use of oxygen, nitrogen, and air. This study demonstrates that pneumatic stripping allows the collection of high-quality whitefish eggs. Moreover, we found that gas flow rates should not exceed 0.5 L∙min−1 to minimize post-spawning mortality in whitefish. The eggs obtained by pneumatic stripping using oxygen, nitrogen, or air had high hatching rates. We assumed that air stripping is a promising approach for improvement of the whitefish stripping procedure. Abstract We describe the technique of pneumatic stripping of whitefish (Coregonus lavaretus) eggs with the use of oxygen, nitrogen, and air. Eggs obtained via the traditional method (by pressing the abdominal surfaces) served as a control group. It was established that the gas flow rate during pneumatic stripping should not exceed 0.5 L∙min−1, since higher air flow resulted in increased post-spawning mortality. The pneumatic stripping method of egg collection was no faster than hand stripping; however, the time required per female was more consistent. It was found that the pH of the ovarian fluid obtained during hand and pneumatic stripping was not related to the success rate of fertilization. Pneumatic stripping resulted in a higher quality of collected eggs and a higher and more consistent hatching rate as compared with the hand-stripped samples, regardless of the gas used. The results presented here lead us to recommend the pneumatic method for obtaining eggs from whitefish, since it is a simple, reproducible method and improves the reproductive performance and developmental success of the fish eggs.

Worldwide, there is a dramatic decline in freshwater eel populations (Anguilla spp.), resulting in an urgent need to improve eel management and artificial reproduction protocols. Unfortunately, eels in captivity do not reproduce spontaneously as they remain in a (pre)-pubertal state resulting from a strong neural blockage. Eel propagation is possible to some extent by applying extensive, expensive, unnatural hormonal treatments. However, the success rates are still far too low to support a sustainable farming industry, due to low gamete quality and low survival rates of larvae. Artificial reproduction of eels has been pursued for almost 80 years, and maturation protocols have changed little. In order to improve current protocols it is clear that a different approach towards stimulating sexual maturation is required. In many fish species, changes in external environmental cues, such as photoperiod and temperature, are crucial to induce gonadal recrudescence and development. Still, the natural triggers involved in the gametogenesis of eels are poorly understood. The time-keeping hormone melatonin is a well-known transmitter of external cues, and influences various physiological processes, including reproduction. In eels, we hypothesize that melatonin is an important key player in the regulation of sexual maturation. Thus far, its mode of action is still an area which needs to be explored. In this review, we provide an overview of the current knowledge of studied natural cues possibly affecting reproductive function and the plausible role of melatonin in the regulation of puberty in eels.

From the start of her career, contemporary Japanese writer Murata Sayaka1 has been writing novels that dismantle the existing politics of gender, family and sexuality through stories set in dystopian or surrealistic worlds. In Satsujin shussan (The Birth Murder) she depicts a society in which a person can kill another if s/he gives birth to other ten. Women are given a contraceptive implant at the time of their first menstruation, sex is conceived as an act of lust, and pregnancy occurs exclusively by assisted fertilization and is also possible for men through the use of artificial uteri. This paper proposes a textual analysis, arguing how Murata creates a feminist “reproductive eutopian dystopia” and breaks both the concept of reproductive body as exclusive to females and the concepts of pregnancy and motherhood. The novel will be explored from a feminist perspective.

Prochilodus lineatus is a South American fish of great economic and social importance that is impacted by high fishing pressure. Restocking programmes have tried to be effective in recovering natural populations; however, genetic and reproductive methodologies are necessary to make feasible the survival of released fingerlings. The genetic variability of P. lineatus subjected to semi-natural and artificial reproduction was evaluated. Caudal fin samples from 25 breeders subjected to an artificial reproduction were collected at different sex ratios (1♂:1♀ and 2♂:1♀), and 138 fingerlings originated from these spawning. Similarly, samples were collected from 10 breeders (1♂:1♀) subjected to a semi-natural reproduction, and 70 fingerlings were generated from this spawning. Ten microsatellite loci were evaluated, producing 142 alleles. High interpopulation variability for broodstock and fingerlings was observed in both reproductive systems. A deficit of heterozygotes through the inbreeding coefficient (Fis) was obtained. Moreover, a deviation in the Hardy–Weinberg equilibrium of the fingerlings in both systems was detected. Fst values indicated a moderate genetic differentiation in 1:1 artificial reproduction system and low differentiation in 2:1 artificial and 1:1 seminatural reproduction system. Despite the high genetic variability, genetics analyses in the next generations of fingerlings will be necessary considering the likelihood of a decrease in genetic variability.

Under present conditions of depletion of natural resources and introduction of a moratorium for commercial sturgeon fishing there is a need to take urgent and radical steps in order to conserve the Caspian populations of these valuable species. Natural and artificial reproduction efficiency shall be improved in order to restore sturgeon population level in the Volga-Caspian basin. The analysis of the current state of natural sturgeon reproduction in the Volga river unregulated part has shown that due to a variety of reasons its efficiency has been minimized. The role and importance of artificial reproduction is increasing, yet in the last years its efficiency has been negated because of increasing deficiency of sturgeon sires in natural populations. Timely composition of productive stocks in the fish ponds of 6 Astrakhan region sturgeon breeding hatcheries allows to provide artificial reproduction fish-breeding operations with high quality spawns and milters within the conditions of their population’s decline in the natural habitats. The data on the quantity and the biomass of the sturgeon productive stocks at the Astrakhan sturgeon hatcheries prove that the prospects for developing artificial reproduction are possible only due to using stocks available at the hatcheries.

Embryonic development of lower vertebrates can be influenced by many factors, especially when outside of the mother's body and under the influence of variable abiotic and biotic factors. In this study, the effects of fertilization of post-ovulatory aged (overmature) oocytes of ide Leuciscus idus on the risk of developing anomalies in ide larvae were assessed under controlled conditions. There was a negative effect of delayed fertilization of post-ovulatory aged (overmature) oocytes in the ovary on the quality of offspring, which caused reduced survival 3 days post-fertilization and at the hatching stage (68.3 vs. 81.2% and 47.2 vs. 79.7% for the overmature and mature groups, respectively). It also increased the occurrence of numerous developmental defects (19.3 vs. 0.8% for the overmature and mature groups, respectively), including the development of Siamese twins. This is the first reported case of the occurrence of Siamese twins in ide. The ide Siamese twins look like hen eggs with 2 heads and are different from 'typical' Siamese twins in fish.

In this study the comparison of spontaneous and hormone-induced reproduction of burbot under controlled conditions was made. During the first two years of the study, burbot spawned spontaneously and artificially after hormonal treatment. The application of sGnRHa resulted in a 100% ovulation rate within 4 to 5 days. Over the 20 days of the experiment, in both years, 65% of females (13 from 20) spawned spontaneously. The biological quality of eggs, expressed as a percentage of live embryos (58.6–60.3%), was generally lower than in only hormone-induced spawned groups (84.2–89.2%). The embryo survival in groups spawned spontaneously decreased in time during the spawning season. Hormonal stimulation of non-ovulated females caused 43–57% of ovulation but with low embryo survival rates (34.2–44.2%). In the third year of the study, 55% of females ovulated spontaneously during the first 10 days of the experiment. Stimulation of non-ovulated females resulted in final oocyte maturation and ovulation in 78% of females. The embryo survival rate was higher (63.2%) than in fish stimulated hormonally after 20 days of spontaneous spawning (but not after 10 days). The application of hormonal treatment in burbot reproduction under controlled conditions shortened latency time, synchronized final oocyte maturation and resulted in high embryo survival rate.

Reproduction of amphibians includes ovulation, spermiation, fertilization, oviposition, larval stage and development, and metamorphosis. A problem at any stage could lead to reproductive failure. To stimulate reproduction, environmental conditions must be arranged to simulate changes in natural habits. Reproductive life history is well documented in amphibians; a thorough knowledge of this subject will aid the practitioner in diagnosis and treatment. Technologies for artificial reproduction are developing rapidly, and some protocols may be transferable to privately kept or endangered species. Reproductive tract disorders are rarely described; no bacterial or viral diseases are known that specifically target the amphibian reproductive system.

Wild fish domestication can be considered a strategic approach to endangered species conservation, supporting studies and reducing economic and environmental costs. Three of the most important strategies in the domestication processes of fish are the adaptation of wild fish to captivity, the reproduction of the adapted fish and the production and maintenance of the young individuals. That being said, the present study is divided in three experiments: the 1st aimed to adapt wild Pseudopimelodus mangurus to captivity environment using different feeding approaches and a prophylactic strategie; the 2nd aimed to reproduce the adapted individuals from the 1st experiment; and the 3rd aimed to train the P. mangurus juveniles to accept commercial diets. The 1st and 2nd experiments were successful at the maintenance and artificial reproduction of P. mangurus kept in tanks between the reproductive seasons. The results suggest that the reproductive performance of animals kept in captivity (initial relative fertility-IRF = 609.25 ± 36.6 eggs/g) was similar (p > 0,05) to the performance found in wild individuals (IRF = 679.21 ± 45.66 eggs/g). Feed training of P. mangurus juveniles (3rd experiment) was also conducted, evaluating three feeding treatments with different concentrations of bovine heart and ration. At the end of the experiment, the treatment containing half bovine heart and half commercial feeding resulted in the highest values of weight gain (0.10 ± 0.16 g), specific growth rate (0.37 ± 0.11 mm), length (47.78 ± 2.35 mm) and growth (2.15 ± 2.27 mm), suggesting reasonable acceptability to artificial diets in the cultivation of this species. As conclusion, the present study contributes with the development of techniques for the domestication of fresh water fish species with commercial value or andangered of extinction, showing the domestication and reproduction of wild P. mangurus in captivity. However, more studies have to be conducted in order to improve the acceptance of artificial feeding by juveniles and to increase their survival rate. Resumo A domesticação de peixes selvagens pode ser considerada uma abordagem estratégica para a conservação de espécies ameaçadas, apoiando estudos e reduzindo custos econômicos e ambientais. Três das estratégias mais importantes para o processo de domesticação de peixes são a adaptação dos peixes ao cativeiro, a reprodução dos peixes adaptados e a produção e manutenção dos indivíduos jovens. O presente estudo está dividido em três partes: a 1ª objetivou adaptar Pseudopimelodus mangurus selvagens ao ambiente de cativeiro usando diferentes abordagens alimentares e uma estratégia profilática; o 2º objetivou reproduzir os indivíduos adaptados do 1º experimento; e o 3º teve como objetivo treinar os juvenis de P. mangurus para aceitar dietas comerciais. O 1o e 2o experimento obteveram sucesso na manutenção e reprodução artificial de P. mangurus mantidos em tanques entre as estações reprodutivas. Os resultados sugerem que o desempenho reprodutivo dos animais mantidos em cativeiro (fertilidade inicial relativa-FIR = 609,25 ± 36,6 ovos / g) foi similar (p> 0,05) ao dos indivíduos selvagens (FIR = 679,21 ± 45,66 ovos / g). O treinamento alimentar de P. mangurus juvenis (3º experimento) também foi realizado avaliando-se 3 tratamentos alimentares com diferentes concentrações de coração bovino e ração. Ao final do experimento, o tratamento contendo metade coração bovino e metade ração gerou os maiores valores de ganho de peso (0,10 ± 0,16 g), taxa de crescimento específico (0,37 ± 0,11 mm), comprimento (47,78 ± 2,35 mm) e crescimento (2,15 ± 2,27 mm), sugerindo razoável aceitabilidade para dietas artificiais no cultivo desta espécie. Como conclusão, o presente estudo contribui com o desenvolvimento de técnicas para a domesticação espécies de peixes de água doce, de interesse comercial ou ameaçados de extinção, mostrando a domesticação e reproduçao de em cativeiro P. Mangurus selvagens. No entanto, mais estudos devem ser conduzidos no intuito de aumentar a aceitação de dietas comerciais pelos juvenis e melhorar sua taxa sobrevivência.

Anesthesia is a common practice used in fish research and aquaculture. It is important to understand anesthetic effects on the animal and tissues of interest to ensure validity of data and to improve animal welfare in research and fish production endeavors. The production of some captive fish species is only possible by imposing artificial reproduction procedures, and manipulation of fish for these purposes is a stressor. The purpose of this study, therefore, was to evaluate effects of different concentrations (100, 200, and 300 mg/L) of the anesthetic MS-222 (tricaine methanesulfonate) on cortisol concentrations and effects on sperm quality in Rhamdia quelen. After hormonal induction of gamete production, 28 sexually mature males were randomly assigned to treatments, and milt and blood samples were collected. Anesthesia induction time, motility rate, sperm concentration and morphology, plasma cortisol concentrations, and reproductive hormone concentrations (testosterone, 17-α-hydroxyprogesterone, and estradiol) were evaluated. Sperm motility was greater in the control than 300 mg/L treatment group but did not differ among the control, 100, and 200 mg/L groups. The estradiol concentration was greater in non- anesthetized than anesthetized Rhamdia quelen, but plasma cortisol concentrations did not differ among treatment groups (182.50 ± 42.03 ng/mL). The anesthetic MS-222 at concentrations of 100, 200, and 300 mg/L did not inhibit the stress response due to handling of Rhamdia quelen males. In addition, treatment with MS-222 was not effective in inhibiting detrimental effects on sperm quality because this treatment was associated with impaired sperm motility and lesser concentrations of plasma estradiol.

Reproduction in captivity of four species of the mormyrid genus Campylomormyrus was investigated. Cyclical reproduction was provoked by changing water conductivity (C) alone: decreasing C led to gonadal recrudescence, an increase induced gonad regression. Data on the reproduction and development of three species are presented. All three species are indeterminate fractional spawners. Spawning intervals ranged from 6 to 66 days in C. rhynchophorus, 10–75 days in C. tshokwe, and 18 days in C. compressirostris (calculated values). Fecundities (eggs per fractional spawning) ranged from 70 to 1570 eggs in C. rhynchophorus, 100–1192 in C. tshokwe, and 38–246 in C. compressirostris. Spawnings/ovipositions occurred during the second half of the night; no parental care was observed; no special spawning substrates were necessary. C. compressirostris successfully spawned in breeding groups, C. rhynchophorus as pair. Agonistic behavior in the C. tshokwe pair forced us to divide the breeding tank; therefore, only ovipositions occurred. However, injection of an artificial GnRH hormone allowed us to obtain ripe eggs and sperm and to perform successful artificial reproduction. All three species produce yolky, slightly sticky eggs. Egg diameter ranges from 2.3–3.0 mm. Hatching occurred on day 3, feeding started on day 11. Transition from larval to juvenile stage occurred at around 20 mm total length (TL). At this size C. rhynchophorus developed a higher body than the two other species and differences between the species in the melanin pigmentation of the unpaired fins occurred. Between 32 and 35 mm TL the upper and lower jaws started to elongate.

This article seeks to explain the consistent margins between popular support for same-sex marriage and same-sex adoption/parenting. I posit that the paradigm of repronormativity explains these differences, in permitting only “legitimate,” state-sanctioned, heteronormative reproduction. Through three case studies—Poland's strict abortion policies, France's law against lesbians utilizing artificial reproduction technologies, and Sweden's history of sterilizing trans individuals—I will demonstrate how not only does repronormativity select and enforce an inside/outside, in-group(s)/out-group(s) binary and legitimize only certain reproduction, it also tethers female sexuality to reproduction and creates an inevitability of reproduction.

This study focused on the reproduction effectiveness of 10 breeding strains of common carp (Polish strains 2, 3, 6; Hungarian strains 0, W, 7; Lithuanian strain B; French strain F; Israeli strain D and Yugoslavian strain J) after stimulation of ovulation with carp pituitary homogenate or Ovopel. The percentage of females with recorded ovulation became higher after Ovopel treatment in as many as eight breeding strains (2, 3, 6, 0, W, B, F, D). The interaction between the spawning agent and the breeding strain was statistically significant (P ≤ 0.05) for the mass of spawn and non‐significant for traits determining the quality of eggs. Among the 10 breeding strains, in 4 (3, 7, B, J) the least‐squares means (LSM) for the weight of egg (g) were higher for fish stimulated with Ovopel. Among the strains tested, in seven (3, W, F, J, 2, 7, B), the LSM for the percentage of living embryos after 36 h incubation were higher for fish treated with Ovopel. The evaluation of reproduction effects based on the values of such parameters as the percentage of ovulating females, weight of eggs (g) and the percentage of live embryos (36 h) showed that after Ovopel treatment the poorer effects were obtained only for strains 6, 0 and D.

Thanks to the achievements of modern science and medicine it is possible to bring to life a child outside of the mother's body. The most popular medical techniques of artificial procreation include artificial insemination and in vitro fertilization (FIVET), artificial insemination by the GIFT and ZIFT methods. The use of artificial reproduction procedures, however, involves the participation of third parties and manipulation of the human person at the earliest stage of its biological development. Artificial reproductive techniques are associated with personal destruction and dehumanization of man, society, human relations and culture. In view of the rampant “logic of relativism” it is necessary to properly show the truth about man, his dignity and recognition of the natural moral law.

To identify the effects of oocyte ageing on egg quality in northern pike, Esox lucius , two experiments were performed as follows: in experiment I, partial volumes of the eggs from 7 pike females were stripped and fertilised with 2-day intervals for 8 days post-ovulation (DPO). In experiment II, the stripped eggs of 3 females were stored in ovarian fluid at 10 °C and fertilised separately with 12-hour intervals for 96 hours post-stripping (HPS). In both experiments, the eggs from each batch were fertilised with mixed milt obtained from 5 males. Eyeing, hatching and eyed-egg mortality rates as well as the occurrence of larval malformations and ploidy anomalies were considered as indices for egg quality. The results of experiment I indicated that the best and most reliable post-ovulatory stripping times in pike were at 2 DPO and up to 4 DPO, respectively, when females were retained at 10 °C. Over-ripening of the eggs occurred from 8 days after ovulation. The eyed-egg mortality and larval malformation rates did not show any significant increase up to 6 DPO, but then increased significantly and reached 36% and 43% at 8 DPO, respectively. The incidence of triploid larvae increased over time, from 0% at 0 and 2 DPO to 11% and 14% in more aged oocytes at 4 and 6 DPO, respectively. The second experiment clarified that the best post-stripping fertilisation time in pike was at 0 HPS. However, stored eggs in ovarian fluid could retain almost 50% of their initial fertilising ability for 24 h after stripping. Complete loss of egg viability occurred after 96 HPS, and the highest eyed-egg mortality rate (27%) and larval malformation rate (33%) were detected in this group. The obtained results suggest that for commercial artificial reproduction procedures in northern pike, the time interval between successive fish examinations for ovulation should not exceed 4 days. In addition, the eggs 1 stripped from the female should be fertilised immediately following collection to secure the highest possible fertilisation rate. Statement of relevance Knowledge of in vivo and in vitro storage of fish eggs can improve hatchery techniques as well as better broodstock management, which are the most important factors affecting synchronization of the artificial fertilisation and consequently the effectiveness of the entire operation. The duration of egg viability after ovulation and stripping has not yet been determined for the pike. A better understanding and refinement of egg storage methods are strongly desirable to maximize the efficacy of mass production in pike hatcheries.

The study evaluated qualitative and quantitative characteristics of Amazonian jundia semen . The experiment was carried out in February 2015 at Cia do Peixe, a company located in Goias state, Brazil, that specialises in fish fry production. Three male L. marmoratus farmed in dugout ponds, weighing 1.34 ± 0.29 kg and measuring 39.33 ± 1.15 cm in length, were tested. The specimens were captured and transferred to a 1000-L tank at the Reproduction Laboratory of the abovementioned company. Water temperature was measured at 7:00 a.m. and 5:00 p.m., and the fish were fed twice daily. For semen collection, the fish were captured from the tank using a dip net and constrained with a wet cotton towel. Their eyes were covered and their urogenital papilla was cleaned and dried with paper towel. Semen was collected in microcentrifuge tubes that were immersed in ice and analysed immediately. On average, the sperm motility rate was 83.33%, motility duration was 5.33 min, sperm concentration was 1,795,833 cells/ mm 3 , and vigour was 4. The morphological analysis of the sperm revealed tail anomalies in 17.66%, midpiece anomalies in 20%, and head anomalies in 5.33%. Based on qualitative and quantitative characteristics, L. marmoratus semen was shown to be suitable for use in artificial reproduction procedures.

The present study aimed at the development of an effective and efficient artificial reproduction technique for cultured female tongue sole (Cynoglossus semilaevis) in out-of-season. After about four-month enriching cultivation of broodstocks, a series of experiments were conducted to develop a protocol for the hormonal induction of ovulation and artificial fertilization. The results showed that single injection of combination of luteinizing hormone releasing hormone analogue (LHRH-A3), human chorionic gonadotropin (HCG) and domperidone (DOM) is effective to induce ovulation at different final maturation stages (i.e., stage IV and V). The optimal single injection dosages of combined hormones were (0.15 μg LHRH-A3 + 4 IU HCG + 2 mg DOM) / kg BW and (0.05 μg LHRH-A3 + 2 IU HCG + 1 mg DOM) / kg BW for females at stage IV and V respectively. At the optimized dose of hormones, the fertilization and hatching rates were 44.6% and 80.4%, 30.4% and 63.4% for stage IV and V respectively. The lapsed time to ovulation was very predictable and ranged from 35.5 to 39.5 h post injection. Ovulated eggs in ovarian cavity should be stripped within 15 min in order to obtain the highest fertilization and hatching rates, otherwise the values decreased significantly thereafter. These researches are expected to provide improved implementation of artificial reproduction techniques for the production of fertilized eggs in the commercial aquaculture of tongue sole.

This abstract was presented at the American Academy of Otolaryngology-Head and Neck Surgery Annual Meeting, Orlando, FL, September 2014 with the abstract published (Neumann C, Thompson D, and Sidman J; Assisted reproduction is not associated with increased risk of head and neck defects; Otolaryngology-Head and Neck Surgery; Vol 151, Issue 1, supplement, 2014). Objectives - Compare the rate of head and neck anomalies between children conceived via artificial reproductive technology (ART) versus those conceived via natural methods. - Determine the risk of congenital head and neck abnormalities associated with ART. Study design A retrospective chart review cross-sectional study from 2004-2014 of all patients admitted to the neonatal intensive care unit (NICU) at a tertiary pediatric hospital. Results A total of 14,857 charts were examined; 2,288 patients were conceived via ART, while 12,569 patients were conceived via natural methods. There were 8,022 males and 6,637 females. There were 40 patients born with defects via ART, while there were 681 patients born with defects via natural conception. The total occurrence of congenital malformations was higher for patients conceived naturally versus those conceived with artificial reproduction (5.41% vs. 1.74%). The odds ratio was 0.31 with a 95% CI of 0.23 to 0.43 and a P-value of < 0.0001; the relative risk of having any one of the head and neck defects with ART was 1.04 with a 95% CI of 1.03 to 1.05 and a P-value < 0.0001. Conclusion There appears to be no increased risk of congenital head and neck defects in children conceived via ART versus those conceived naturally.

Controlled reproduction is a requirement for developing effective mollusc cultivation for commercial or restoration purposes. In this study, a protocol for spawning induction using noninvasive methods in limpets was developed, using the common Mediterranean species, Patella caerulea Linnaeus, 1758. Six nonlethal spawning induction treatments were tested: three chemical (two concentrations of H₂O₂ and KCl) and three physical (bubbling, warm and cold thermal shock). All treatments, except thermal shocks, induced the spawning of fertile gametes. Bubbling resulted the best treatment in providing spawning response, being the easiest and least invasive method tested. After eggs fertilization, larval development was followed until metamorphosis, testing fed and unfed conditions. Settlement took place after 7 days. The developed protocol represents a benchmark for further application to other limpets, for aquaculture or repopulation.

Elimination of egg stickiness is an important factor in artificial reproduction of pikeperch (Sander lucioperca L.). This study was conducted to evaluate the effectiveness of Alcalase enzyme to remove the adhesive layer of pikeperch eggs. The eggs were treated with Alcalase at 0.5, 1.0, 1.5, 2.0 and 5.0 mL L−1 or a milk/talc solution 2 min post insemination. Duration of exposure was 2 min in Alcalase and 60 min in milk/talc. The highest, albeit not significant, hatching rate (85.4%) was found with 1.5 mL L−1 of Alcalase, but hatching rates were similar in 0.5, 1.0 and 2.0 mL L−1. Hatching rates were significantly lower groups treated with 5.0 mL L−1 Alcalase enzyme (56.4%) compared to groups treated with milk powder and talc (61.3%). Nominally complete removal of adhesiveness was observed in 1.5 and 2 mL L−1. All Alcalase treatments led to significantly lower incubation duration compared with the traditional milk/talc treatment. The application of Alcalase successfully eliminated pikeperch egg stickiness in less time than with traditional milk/clay/talc methods.

This study aimed to compare the fertility of eggs between artificially matured female silver eels that spawned spontaneously and those that were spawned by manual stripping. The effects of the two methods of spawning on ovulation and fertilization rate were also investigated. For this purpose, 18 wild female European els captured in Bonello lagoon (North Adriatic Sea) were carp pituitary extract-injected to undergo sexual maturation and ovulation; a final injection of 17,20b-dihydroxy-4-pregnen-3-one (DHP) was administered when at least 30% of the oocytes were fully transparent. After the DHP-injection, nine eels were transferred to a new closed recirculating aquaculture system, where they were housed with spermiating males (sex ratio 4/1) to allow spontaneous spawning (SPT-group); the remaining nine eels were transferred to a 250 L tank and ovulation was checked at four-hourly intervals by manual stripping (STR-group). The number of eggs per female in the SPT-group was significantly greater than that in the STRgroup. Furthermore, fertilization rates in the SPT-group were notably higher than those observed in the STR-group. Significantly, the best performances were obtained among eels in which at least 50% of oocytes were fully transparent at the time DHP was administered. We conclude that the fertility of eggs from spontaneously spawning eels is superior to that of eggs acquired by strip-spawning and artificial fertilization.

When artificial reproduction technologies designed for use with horses are used with donkeys, success is dependent on awareness of the physiological differences between these species, yet little information is available on many aspects of donkey reproduction. The present work examines the activity of the CL in Catalonian jennies after induced luteolysis. Plasma progesterone concentration, luteal blood flow (determined by color Doppler), and CL cross-sectional area (CL-CSA; determined by B-mode ultrasound examination) were assessed after a single dose (5 mg intramuscular) of dinoprost thromethamine (DT, a PGF2α analog) on Day 10 after ovulation in two experiments. In experiment 1, a preliminary experiment, data were collected daily for 4 days after DT administration. Values for all the measured variables decreased over this period. In experiment 2, data were collected during the first 24 hours after DT administration because in experiment 1, most luteolytic activity occurred during this time. An increase in luteal blood flow was seen between 0 and 3 hours, followed by a progressive reduction, whereas the values for plasma progesterone and CL-CSA gradually decreased from 0 hours onward. In both studies, negative correlations were seen between all variables and the time of sampling. In contrast, positive correlations were seen between plasma progesterone, CL-CSA, uterine tone, and luteal blood flow. Indeed, a strong correlation was recorded between plasma progesterone and luteal blood flow (r = 0.70; P

Optimization of works on the artificial reproduction of Siberian sturgeon(Acipenser baerii Brandt) by improving technological and organizational methods will be able to increase significantly the efficiency of sturgeon farm reproduction, serve a prerequisite for preserving the genetic diversity, and restore its stocks in natural reservoirs of Western Siberia.

Stress can be defined as a condition in which the dynamic equilibrium of the body is disturbed and several studies have demonstrated the action of some corticosteroids modulating stress situations, such as reproduction. However, the role of corticosteroids in fish reproduction can be either positive or deleterious, depending on many variables. In the Astyanax genus, the same stress stimulus can successfully induce the reproduction in Astyanax altiparanae, but not in other species of the same genus. Therefore, the aim of this study was to analyze cortisol and progestogens plasma levels and receptor gene expression in the ovaries of A. altiparanae, a teleost species that successfully reproduce using crowding and water level drawdown as stimulus. Three experimental groups were considered: Stress (high stocking density and water level drawdown); human chorionic gonadotropin (hCG, a positive control); and Saline (a control group). Females were sampled at three different moments of the artificial reproduction experiment, initial, intermediary and at spawning. Indices of spawning performance as, fertilization rate, Gonadosomatic Index (GSI), as well as histological analysis of the ovaries were carried out. 17α-hydroxiprogesterone (17 OHP) and cortisol (CORT) levels were measured in plasma by ELISA. Additionally, the ovarian gene expression of CORT and 17 OHP receptors (CR and PR) were carried out by Real-time quantitative PCR. Females from Stress and hCG groups released a larger volume of eggs when compared with females from the Saline (Control) group. Females from Stress group presented a decrease in GSI and ovaries mass at spawning, and many post ovulatory follicles (POFs) were present in the ovaries after spawning. At the intermediary sampling, plasma levels of CORT increased in females from the Stress group, but not in the hCG and Saline groups. 17 OHP levels did not change during the experiment. PR gene was more expressed in females from hCG group throughout the experiment, but CR gene expression did not change. We suggest a possible role of CORT as an inducing agent in ovulation and/or spawning of A. altiparanae. CR and PR did not seem to be the candidates for triggering ovulation, so the relationship between the derivative of progesterone (17,20DHP) should be deeper studied, as well as the role of CORT and different progestagens in A. altiparanae reproduction O estresse pode ser definido como uma condição na qual o equilíbrio dinâmico do corpo é perturbado e muitos estudos têm demonstrado a ação de alguns corticosteroides modulando situações de stress, tal como a reprodução. No entanto, o papel dos corticosteroides na reprodução de peixes pode ser positivo ou deletério, dependendo de muitas variáveis. No gênero Astyanax, o mesmo estímulo de estresse pode induzir com sucesso a reprodução em A. altiparanae, mas não em outras espécies do mesmo gênero. Portanto, o objetivo deste estudo foi analisar os níveis de cortisol e progestágenos no plasma e a expressão dos receptores destes esteroides nos ovários de A. altiparanae, espécie de teleósteo que consegue se reproduzir com sucesso usando o aumento da densidade e variação no nível da água como um estímulo. Três grupos experimentais foram considerados: Estresse (alta densidade de estocagem e intenso fluxo de água); Gonadotropina Coriônica Humana (hCG, um controle positivo); e Salina (grupo controle). As fêmeas foram amostradas em três diferentes momentos do experimento de reprodução artificial, inicial, intermediário e na desova. Índices de desempenho de desova como, taxa de fertilização, Índice Gonadossomático (IGS), bem como a análise histológica dos ovários foram considerados. Os níveis de 17α-hydroxiprogesterone (17 OHP) e cortisol (CORT) foram medidos em amostras de plasma por ELISA. Além disso, a expressão de genes de receptores de CORT (CR) e 17 OHP (PR) foram analisadas nos ovários por qPCR. Fêmeas dos grupos Estresse e hCG desovaram um volume maior de ovos quando comparadas às fêmeas do grupo Salina (controle). As fêmeas do grupo Estresse apresentaram também uma redução nos valores do IGS e na massa dos ovários no momento da desova, e muitos folículos pós - ovulatórios estavam presentes nos ovários após a desova. Na amostragem do período intermediário, os níveis plasmáticos de CORT aumentaram nas fêmeas do grupo de Estresse, mas não nos grupos de hCG e Salina. A concentração de 17OHP não se alterou durante o experimento ou entre os grupos. O PR foi mais expresso em fêmeas do grupo hCG ao longo do experimento, e a expressão do CR não se alterou. Sugerimos um possível papel de CORT como um agente indutor na ovulação e / ou de desova de A. altiparanae. No entanto, CR e PR não parecem ser os candidatos para desencadear a ovulação, de modo que a relação entre receptores derivados PR (17,20DHP) devem ser mais profundamente estudados, bem como a efetiva ação de CORT e diferentes progestágenos na reprodução de A. altiparanae