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In the psychosomatic approach to human reproduction, we think it necessary to take into account some general characteristics intrinsic to this function in its continuum and/or to particulars relative to some moments of it, apart from individual, environmental and social factors. Therefore, we must take into consideration: a) The biological significance of reproduction in the general economy of the individual and the natural behavior and specific mechanisms of the different aspects of this function. b) The homeostatic characteristics of the function itself (automatisms, autoregulation). c) The homeostatic characteristics between the reproductive function and the individual (high level and at-risk functions). d) The homeostatic characteristics between the environment and the individual during reproduction. e) Relationships between natural and artificial reproduction and its control, and specific emotionalities.

Publisher Summary As fish farming expands and harvesting of wild stocks becomes more intense, there is a growing need for techniques for storage of gametes to facilitate artificial reproduction procedures and to preserve desirable gene pools. Cryogenic gene banking of fish gametes is now possible for sperm cells from several species, but not for ova and embryos. This chapter reviews the aspects of fish gamete preservation. The chapter reviews all available information and presents a separate treatment of salmonids. Compared to egg cells, sperm cells are preferred for preservation. The reasons are the large number of available spermatozoa, the ease and repeatability of collection, and the suitability for cryopreservation. Because information about fish spermatozoa morphology, metabolism, and motility is rather scarce and scattered in the literature, these subjects are given particular attention. The chapter discusses the general aspects of cryobiology.

National audience; Various observations and results of experiments carried out in the hatchery of the "Conseil Supérieur de la Pêche" in Augerolles are presented, concerning the technics of artificials pawning adapted to the physiology of grayling . It is shown that th e physiological characteristics are nearly t he same as those of brown trout . Nevertheless highs ensitivity to low temperatures reduces the speed of the finaloocyte maturation. These observations and experiments lead the authors to give practical recommendations.; Diverses observations et résultats d'expériences réalisées à la Salmoniculture du Conseil Supérieur de la Pêche à Augerolles sont présentés, concernant les techniques de reproduction artificielle adaptées à la physiologie de l'Ombre commun. Les caractéristiques physiologiques mises en évidence sont proches de celles de la Truite avec cependant une sensibilité accrue aux basses températures , qui peuvent ralentir très fortement la fin de la maturation ovocytaire. Ces observations et expériences conduisent les auteurs à formuler un certain nombre de conseils pratiques.

L'Ombre commun (Thymallus thymallus) est un poisson très apprécié des pêcheurs à la mouche, qui a fait l'objet d'un élevage limité à la production de sujets de repeuplement.

National audience; L'Ombre commun (Thymallus thymallus) est un poisson très apprécié des pêcheurs à la mouche, qui a fait l'objet d'un élevage limité à la production de sujets de repeuplement.

Biology of gametes, eggs and embryos

Genetically identical copies of the silkworm female obtained via ameiotic parthenogenesis are insignificantly depressed by artificial reproduction, and notwithstanding their isogenous pattern, they show the same variability in quantitative characters as in the heterogenous forms.By means of androgenesis, genetically identical copies of strictly homozygous males were obtained; the latter were produced via meiotic parthenogenesis. The androgenetic clones of these males were transformed by backcrosses into homozygous bisexual lines. Viability and cocoon weight in these lines were higher than those in androgenetic clones of similar genotype, but they were far from the norm due to the depressing effect of semilethals left in them in a homozygous state. An extremely low phenotypical variability of quantitative characters is observed in the isogenous hybrids F1 obtained from crossing two genetically dissimilar strictly homozygous individuals. These hybrids make excellent material for phenogenetical studies. The female and male isogenous clones have an increased combining ability which is acquired in the course of their selection for high disposition towards complete parthenogenesis. For practical purposes it is proposed to take a female and a male which when mated produce a high-quality family and clone them separately, the first via parthenogenesis, the latter via androgenesis. After mating these reproduced bisexual clones, it will be possible to obtain in successive generations a vast number of families repeating the prominent productivity of the initial family.

Survival of pike broodstock was evaluated 2–3 months after reproduction during two spawning seasons. In females, the highest survival rates (79–85%) were recorded following managed natural spawning. Spontaneously ovulated females submitted to ova collection by hand stripping had intermediate survival rates (32–45%). Low survival (20–21%) was observed in females subjected to gonadotropic treatment, captivity between hormone administration and ovulation, and ova collection. Survival of males was significantly higher after natural spawning (52–62%) than following a single sperm collection (5–7%). In both sexes, survival was clearly influenced by the degree of handling or environmental change experienced. A peak in mortality of broodstock used for artificial reproduction occurred in April and was concomitant with a sharp increase in water temperature.

Mature eggs were expressed from captured female and fertilised artificially with slightly bloody sperm, in dry conditions or in a humid atmosphere, both at 13 degree C. The best incubation conditions proved to be 13 degree C, with streptomycin and penicillin. Another sample was kept at 18 degree C. Hatching occurred after 4 or 5 days, larvae showing positive phototropism. The system of renewal of water and artificial food is described. The embryonic reserve drop of lipid disappeared between day 14 and 16. Observations on larvae were like previous ones, but live larvae had larger mouths than had fixed specimens, and it was found that temperatures of 13 degree C or 18 degree C were suitable beyond the egg stage. A sudden change in temperature caused by a storm killed the larvae, which seemed also to be sensitive to water movements and light. It is suggested that water movements, and thus movement of food particles, stimulates the larvae into behaviour patterns essential to survival. The difficulties or artificial cultivation of Bass thus suggested are discussed.

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To improve controlled reproduction of Eurasian perch Perca fluviatilis, the criteria for the evaluation of final oocyte maturation stages were revised. The new classification covers six preovulatory maturational stages (I -VI) from the end of vitellogenesis to germinal vesicle breakdown (GVBD) and was based on macroscopic changes of preovulatory oocytes (position of the germinal vesicle, GVBD, oil droplets coalescence). The observation was performed during out-of-season artificial reproduction with the use of a single hCG injection (500 IU/kg). The classification was subsequently verified with the controlled reproduction of wild female perch with the use of hormonal stimulation (500 IU hCG/kg of body weight at 12°C). The females were at different maturational stages and constituted respective experimental groups (I-VI). During the experiment, ovulation appeared to be considerably synchronized within particular groups. Statistical differences in latency time (time between hormonal treatment and ovulation) were found between experimental groups (mean latency time: 110, 92, 68, 49, 29 and 18 h in groups representing VI, V, IV, III, II and I stage of the proposed classification, respectively). The proposed classification and the results presented in the study allowed for effective synchronisation of ovulation. The use of our new oocyte maturation classification may positively influence the effectiveness of Eurasian perch production.

The black soldier fly (BSF), Hermetia illucens (L., 1758) (Diptera: Stratiomyidae), is an endemic fly species from the tropical, subtropical and warm temperate zones of America. This saprophagous species relies on its environment where it finds the decomposing matter for the larvae to grow. The polyphagous diet and the macronutrient quality (mainly lipids and proteins) of these larvae make them excellent candidates for various applications such as waste and organic material management, incorporation in animal feed or alternative energy source. Although rearing development in temperate regions requires artificial processes to continuously produce high quality eggs and larvae, few studies have been conducted on the mating and oviposition processes governing H. illucens reproduction. Research conducted in semi-artificial rearing conditions showed that the number of mating varied according to the season. It has been speculated that this behavior could be due to differences in the intensity of sunlight caused by the change of seasons. This study aims at evaluating the influence of sex-ratio, density and nycthemeral cycle on H. illucens reproduction. In order to tackle this issue, an artificial set up for oviposition to collect eggs has been developed. This egg collection system aims at centralize oviposition and simplify eggs collection. Two populations with opposite sex-ratio (male-dominant and female-dominant) were selected. Their respective eggs productions have been evaluated for five breeding densities. Eggs weights varied significantly among the densities for each opposite sex-ratio population and female dominant population produced most eggs weight from 6500 individuals /m3. Finally, four nycthemeral cycles (2, 6, 12 and 18h of daily light) were simulated to evaluate the impact of light duration on reproduction. Early oviposition pic associated with a decrease of the oviposition period are shown when H. illucens are exposed to increasing light duration. These experiments enable improvement of the understanding on artificial reproduction of H. illucens.

With the aim of preserving and increasing endangered stocks of white-clawed crayfish, research on juvenile production has been carried out. Advantages in application of newly developed techniques of egg storage, transport and artificial incubation techniques are discussed. Eggs can be removed from maternal pleopods during the early stages of embryonic development and placed in artificial incubation devices. This practice avoids egg losses caused by aggressive contacts, female disease or death and the production of stage-2 juveniles in different batches by means of temperature manipulation. Furthermore transmission of pathogens from broodstocks to offspring can be minimised. Egg storage and transport have some advantages in the artificial reproduction of crayfish. Firstly, embryonic development continues under storage conditions and thus water and human effort can be saved during this period. Temperature plays an important role on both efficiency rates and duration of embryogenesis. Secondly, egg transport could facilitate restocking programs, as there is no need to move berried females to other habitats. To sum up, the combined use of artificial incubation and storage/transport techniques could have important applications to the development of astacid crayfish culture.

The aim of this study was to determine the effects of variable and constant thermal conditions on embryonic development of three endangered fish species from the genus Leuciscus. Wild living spawners of dace Leuciscus leuciscus (L.), ide L. idus (L.) and chub L. cephalus (L.) were obtained from rivers belong - ing to the Pasleka River basin (northeastern Poland) and next transported to a hatchery for the purpose of conducting artificial reproduction. The obtained eggs were fertilized and next incubated under a variety of thermal protocols: slow gradual heating of water (M1), rapid increase in temperature at the end of incuba tion (M2), fluctuating temperature (M3) and two constant temperatures (optimum and sublethal). Variable thermal changes of water were also continued after hatching, up to the yolk sac resorption by larvae. During the study it was shown that relative to incubation at optimal temperatures (12.3°C for dace, 15.7°C for ide and 19.0°C for chub), thermal modifications had no clear influence on a decrease in survival rates (differences among regimes did not exceed 5%) and increase in developmental deformations (differences below 1.0%) observed among the hatched embryos. The duration of egg incubation and developmental rate increased with increasing temperature . In the systems with modified temperature the embryonic development of dace (from fertilisation to commencement of exogenous food intake) took from 9.5 to 22.5 days, for ide from 6.1 to 12 days and for chub from 5.0 to 10.5 days. The yolk sac resorption stage in the particular species occurred from 11.7 to 23 days for dace, 7.5 to 13.2 days for ide and 5.5 to 12.8 days for chub. Different time of hatch - ing was also reflected in the level of ontogeny of hatched embryos. Among the fish hatched at modified temperatures the largest sizes, similar to those characteristic of fish incubated at optimum temperatures, were observed in individuals originating from variants where the temperature fluctuated. The developmental disproportions among the embryos of studied species originating from different thermal regimes observed at the time of leaving the egg shells were definitely larger than during the following development stages. This study also confirmed that the embryos of studied species can adapt to increasing water temperature due to global warming up to 19.0 (dace), 23.0°C (ide) and 27.5°C (chub). The obtained results are very important not only for practical purposes but also from physiological and ecological aspects.

The Wait Goes On In 1982 questions were raised in the Dutch parliament about the new developments in artificial reproduction. In response, the Minister of Health decided to ask the Health Council for advice on the ethical, social and psychological aspects of artificial reproduction. The Health Council is an advisory board to the Minister of Health on the state of scientific developments within medicine and related disciplines. In 1983 the Health Council set up an advisory committee. While the committee was studying the different aspects of artificial reproduction, however, developments threatened to get out of hand: several hospitals began offering in vitro fertilization and plans were made to open private clinics. Therefore, in October 1984 the Health Council decided to issue an interim report, which dealt only with technical issues such as the planning and organization of in vitro fertilization ("And in the Netherlands, Guidelines for IVF," Hastings Center Report, August 1985, 6.) The Council's final report was not published until October 1986. Among their recommendations were the following: When donor semen (or ovum) is used, the resulting child is entitled to general information about the donor but not to information as to his or her identity. Lesbian couples and single women are entitled to the treatment (on medical indication) if they are able to provide for a regular "father figure" in the life of their child. Commercial surrogacy through agencies must be prohibited. But the Council proposed to accept a form of governmentally controlled noncommercial mediation of surrogacy and in those cases to quicken adoption procedures. Fertilization of human egg cells is allowed only with a view to establishing a pregnancy. Forming embryos exclusively for experimentation is considered ethically unacceptable. Experimentation with leftover embryos must be prohibited unless the issue at stake is immensely important for many people and there is no other way of gathering the knowledge. The following experiments are considered ethically unacceptable: genetic therapy on pre-embryos, cloning of embryos by cell-splicing, formation of chimeras and using animals as surrogates. (See also, "In The Netherlands, Tolerance and Debate," Hastings Center Report, Special Supplement June 1987, 15-16). The Dutch government did not respond to this report until September 1988 when it finally issued a statement on "Artificial Fertilization and Surrogacy." The statement deals with existing and future policy, legal aspects of artificial reproduction and surrogacy according to Dutch law, and the point of view of the government toward several aspects of artificial reproduction. …

R. Snowden, G.D. Mitchell, and E.M. Snowden, the authors of Artificial Reproduction, focus on the familial and social repercussions of artificial insemination by donor (AID) and on that basis make generalizations about the societal impact of the new reproductive technologies as a whole. The book gets its drive from an English research project at the Institute of Population Studies, University of Exeter, which included a study of 1,000 cases of AID, in-depth discussions with over sixty AID couples, and contact with AID children, donors, and practitioners.