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Johansen examines the role of internal heat in the theories of nutrition and animal generation in Plato’s Timaeus. There, Plato does not ascribe the status of being besouled to all beings which engage in nutrition, but to beings with perceptive faculties. This raises questions as to the status of nutrition in the explanation of life and besouled beings.
The family Syllidae, aside from representing the most species-rich family in Annelida, is characterized by a number of sexual and asexual reproductive strategies. With the exception of a few viviparous species, the subfamily Syllinae is characterized by schizogamous reproduction with pelagic larval stages and without parental care. Laboratory rearing of ripe specimens of Syllis rosea showed a different reproductive strategy, hitherto unknown in this subfamily. While male stolons rapidly degenerated after fertilization, female ones released large eggs in a gelatinous cluster attached to the middle-posterior chaetigers. The gel mass progressively compacted as a cocoon wrapped by the stolon body; 7 days after the deposition the larvae hatched out from the cocoon at the metatrochophore stage and the female stolon died after a few days. After hatching the larvae remained associated to the stolon, and young specimens of S. rosea survived up to the 3-chaetiger stage. Until now cocoon brooding by the stolon has only been reported for some Autolytinae. The production of gelatinous egg masses and parental care are known in basally branching clades within Syllidae, suggesting that this reproduction mode might retain some ancestral features. The scarce knowledge about reproductive cycles in Syllinae does not allow clarification whether this strategy is unique for S. rosea, or it occurs in other congeneric species. Further research is needed to understand possible relationships between sexual reproduction and phylogeny, stolon morphology and its adaptation to parental care, and ultimately between reproductive strategies and ecology.
Reproductive traits have a major influence on the economic effectiveness of horse breeding. However, there is little information available. We evaluated the use of reproductive traits as selection criteria in official breeding programs to increase the reproductive efficiency of breeding studs, analysing 696 690 records from the pedigree data of eight Spanish horse populations, with different breeding purposes. The reproductive parameters studied in both sexes were age at first foaling (AFF), age at last foaling, average reproductive life and generational interval. In the females, the average interval between foaling (AIF) and interval between first and second foaling were also studied. There were clear differences between sexes and breeds, which may be due to management practices, breeding purposes and the status of the populations, rather than to differences in actual physiological conditions. Riding mares were the most precocious (AFF, 1937.64 to 2255.69 days) and had a more intensive reproductive use (AIF, 625.83 to 760.07 days), whereas sires used for meat production were the most precocious males (AFF, 1789.93 to 1999.75 days), although they had a shorter reproductive life (1564.34 to 1797.32 days). Heritabilities (0.02 to 0.42 in females and 0.04 to 0.28 in males) evidenced the genetic component of the reproductive traits, with Sport Horses having the higher average values. These results support the selection by AFF to improve reproductive aspects because of its medium–high heritability and its positive correlations with other important reproductive traits. The inclusion of the AIF is also recommended in sport populations, because this determines the length of the breaks between foaling and conditions the reproductive performance of the dams, as well as their selective intensity, genetic gain and genetic improvement. It is therefore an important economic parameter in breeding studs.
Piglet birth weight and within-litter birth weight variation are important for piglet survival and growth. Pre-mating diets may improve IGF-1 and follicle development during the weaning-to-oestrus interval (WEI) and subsequent piglet birth weight. The objective of this study was to modulate IGF-1 concentration during late lactation and the WEI of young sows by using specific pre-mating diets supplemented with microfibrillated cellulose (MF), l-carnitine (LC) or l-arginine (AR). A further objective was to investigate the relationship between IGF-1 and subsequent follicle development and oestrus and ovulation characteristics. In total, 56 first-parity and 20 second-parity sows in three consecutive batches were used for this experiment. Sows received daily either wheat (CON) or wheat plus MF, LC or AR at one of two supplementation levels (low and high) during last week of lactation and WEI. From weaning onwards, follicle and corpus luteum (CL) diameters were repeatedly measured with ultrasound. Blood samples were collected during the WEI for IGF-1 and on day 21 of pregnancy for progesterone analyses, respectively. Insulin-like growth factor-1 concentration, follicle diameter, oestrus and ovulation characteristics and CL diameter were not affected by pre-mating diets. Low IGF-1 class (≤156 ng/ml, N = 22) sows had smaller follicles at weaning (3.5 v. 3.8 mm, P < 0.05) and a longer weaning-to-ovulation interval (147.2 v. 129.8 h, P < 0.05) than high IGF-1 class sows. In first-parity sows, high loin muscle depth (LM) loss sows (≥8%, N = 28) had lower IGF-1 concentrations at weaning (167 v. 214 ng/ml, P < 0.05) compared to low LM loss sows (<8%, N = 28). However, after weaning, IGF-1 concentrations increased and did not differ between high LM loss and low LM loss sows. In conclusion, the different supplemented compounds in pre-mating diets did not improve IGF-1 concentrations around weaning in young sows. Furthermore, high body condition loss caused lower IGF-1 concentrations at weaning, but these levels rapidly recovered after weaning and were related to follicle development and the interval from weaning to ovulation.
In teleosts, vitellogenin (Vtg) is a phospholipoglycoprotein synthesized by the liver, released into the blood circulation and incorporated into the oocytes via endocytosis mediated by the Vtg receptor (VTGR) to form the yolk granules. The VTGR is crucial for oocyte growth in egg-laying animals but is also present in non-oviparous vertebrates, such as human. The VTGR belongs to the low-density lipoprotein receptor superfamily (LDLR) and is also named very-low-density lipoprotein receptor (VLDLR). In this study, we identified and phylogenetically positioned the VTGR of a basal teleost, the European eel, Anguilla anguilla. We developed quantitative real-time PCR (qRT-PCR) and investigated the tissue distribution of vtgr transcripts. We compared by qRT-PCR the ovarian expression levels of vtgr in juvenile yellow eels and pre-pubertal silver eels. We also analyzed the regulation of ovarian vtgr expression throughout vitellogenesis in experimentally matured eels. The Vtg plasma level was measured by homologous ELISA experimental maturation. Our in silico search and phylogenetical analysis revealed a single vtgr in the European eel, orthologous to other vertebrate vtgr. The qRT-PCR studies revealed that vtgr is mainly expressed in the ovary and also detected in various other tissues such as brain, pituitary, gill, fat, heart, and testis, suggesting some extra-ovarian functions of VTGR. We showed that vtgr is expressed in ovaries of juvenile yellow eels with no higher expression in pre-pubertal silver eels nor in experimentally matured eels. This suggests that vtgr transcription already occurs during early pre-vitellogenesis of immature eels and is not further activated in vitellogenic oocytes. European eel Vtg plasma level increased throughout experimental maturation in agreement with previous studies. Taken together, these results suggest that vtgr transcript levels may not be a limiting step for the uptake of Vtg by the oocyte in the European eel.
We investigated the efficiency of the autoregressive repeatability model (AR) for genetic evaluation of longitudinal reproductive traits in Portuguese Holstein cattle and compared the results with those from the conventional repeatability model (REP). The data set comprised records taken during the first four calving orders, corresponding to a total of 416, 766, 872 and 766 thousand records for interval between calving to first service, days open, calving interval and daughter pregnancy rate, respectively. Both models included fixed (month and age classes associated to each calving order) and random (herd-year-season, animal and permanent environmental) effects. For AR model, a first-order autoregressive (co)variance structure was fitted for the herd-year-season and permanent environmental effects. The AR outperformed the REP model, with lower Akaike Information Criteria, lower Mean Square Error and Akaike Weights close to unity. Rank correlations between estimated breeding values (EBV) with AR and REP models ranged from 0.95 to 0.97 for all studied reproductive traits, when the total bulls were considered. When considering only the top-100 selected bulls, the rank correlation ranged from 0.72 to 0.88. These results indicate that the re-ranking observed at the top level will provide more opportunities for selecting the best bulls. The EBV reliabilities provided by AR model was larger for all traits, but the magnitudes of the annual genetic progress were similar between two models. Overall, the proposed AR model was suitable for genetic evaluations of longitudinal reproductive traits in dairy cattle, outperforming the REP model.
To understand the production factors that affect conclusive parameters of sow herd performance can improve the use of the resources and profitability of farm. The objective of this study was to identify associations and quantify the effects of a set of factors related to piglet weight at weaning (PWW), kilograms of piglets weaned per sow per year (kgPWSY) and sow feed conversion (SFC). Data from 150 farms were collected, for a total study population of 135 168 sows, including gilt replacement, breeding (mating), gestation and farrowing/lactation phases. A questionnaire focusing on reproductive performance, management, facilities, feeding, health and biosafety was administered. Multiple linear regression models were used to assess associations among factors with each of the three dependent variables. Increased duration of lactation was positively associated with PWW, kgPWSY and SFC. The increase in the number of live born pigs per litter was positively associated with kgPWSY and with SFC. Farms with higher PWW had farrowing room humidifiers, did not surgically castrate male piglets and used quaternary ammonia compounds for farrowing room disinfection. Farms with higher kgPWSY used lined ceilings in farrowing rooms and winter feeds with higher CP percentages in gestation; they also had more farrowings per sow per year. Sow feed conversion was worse in farms with partly slatted floors during gestation, in farms feeding lactating sows six times a day or ad libitum and farms with a higher sow-handler ratio. This study indicates that farms can increase PWW and kgPWSY and improve the SFC by changing one or more management, biosafety and feeding practices or facilities as well as by focusing on improving several performance parameters, particularly increasing the duration of lactation and the number of live born pigs per litter.
Lassa fever (LF) is increasingly recognised as an important rodent-borne viral haemorrhagic fever presenting a severe public health threat to sub-Saharan West Africa. In 2017–18, LF caused an unprecedented epidemic in Nigeria and the situation was worsening in 2018–19. This work aims to study the epidemiological features of epidemics in different Nigerian regions and quantify the association between reproduction number (R) and state rainfall. We quantify the infectivity of LF by the reproduction numbers estimated from four different growth models: the Richards, three-parameter logistic, Gompertz and Weibull growth models. LF surveillance data are used to fit the growth models and estimate the Rs and epidemic turning points (τ) in different regions at different time periods. Cochran's Q test is further applied to test the spatial heterogeneity of the LF epidemics. A linear random-effect regression model is adopted to quantify the association between R and state rainfall with various lag terms. Our estimated Rs for 2017–18 (1.33 with 95% CI 1.29–1.37) was significantly higher than those for 2016–17 (1.23 with 95% CI: (1.22, 1.24)) and 2018–19 (ranged from 1.08 to 1.36). We report spatial heterogeneity in the Rs for epidemics in different Nigerian regions. We find that a one-unit (mm) increase in average monthly rainfall over the past 7 months could cause a 0.62% (95% CI 0.20%–1.05%)) rise in R. There is significant spatial heterogeneity in the LF epidemics in different Nigerian regions. We report clear evidence of rainfall impacts on LF epidemics in Nigeria and quantify the impact.
In the Federal Republic of Germany, intentional alteration of the genome of germline cells and embryos is prohibited by criminal law. This ban is the result of legislation that was adopted more than twenty-five years ago. However, the rapid emergence of genome manipulation techniques, coupled with recent technological developments, is increasingly exposing the senescence of the regulatory framework. With the advent of genome editing, there has been a shift in the national debate on the use of genetic engineering. Until recently, the discussion regarding the use of genome altering methods had been more about the application of genetic engineering to plants (so-called ‘green genetic engineering’) than to humans (so-called ‘red genetic engineering’). After all, green genetic engineering has been present in the fields for years, and sometimes even on the plate, while most red genetic engineering efforts have been unspectacular cell biology basic research, slowed down by both technical and legal hurdles. However, the emergence of more precise, safer and more predictable genome editing methods has now brought the issue into German public discourse and, as evidenced by this volume, around the world.
For historical, social, political and religious reasons, Italy has traditionally approached life sciences, especially those involving humans, with great caution. The main law touching on human germline genome modification, called Law 40/2004 (‘Rules on Medically Assisted Reproduction’) bans most ‘experimentation’ on human embryos. In addition, EU Regulation 536/2014 contains a ban on clinical research using germline modification technologies. Nevertheless, Article 13 of Law 40/2004 leaves the door open to clinical applications of germline modification technologies. However, only the improvement of basic research on gametes would permit in the future to decide if, and possibly identify which, clinical applications are scientifically feasible and ethically acceptable. Recent developments and new possibilities in the field of human germline genome modification call for regulations that, while setting limits to contain possible abuses, do not wholly frustrate scientific and technological progress. Moreover, human germline genome modification technologies, which have enormous therapeutic potential, can further certain values enjoying a constitutional status under the Italian legal system, such as the promotion of scientific progress and the protection of health.
Australia was at the cutting edge in the development of Artificial Reproductive Technology in the 1960s and 1970s. Regulatory responses were piecemeal: only a small number of the six states and two territories enacted legislation. The regulatory response to reproductive cloning and embryonic stem cell research has been more uniform, with nationally consistent legislation in the form of the Prohibition of Human Cloning for Reproduction Act 2002 and the Research Involving Human Embryos Act 2002, together with the Gene Technology Act 2000. This regulatory regime creates a prohibitory environment for germline genome therapy in Australia and provides little scope for genome editing research involving human embryos, even under licence. This chapter discusses the Australian regulatory regime, with particular focus on this triad of legislative instruments. Although Australia has made a commitment to science and health, and recognition of the right to found a family, the special status of the embryo is a paramount consideration. This chapter concludes that, as in many other countries, Australia is at a crossroads, and Australians must decide, collectively, how far genome editing research involving human embryos should be allowed to progress.
Canada’s approach to human germline modification is generally conservative, at times unclear, and largely prohibitive from both a research and clinical perspective. To date, no research using human germline modification has been undertaken in Canada. This chapter provides an overview of the Canadian legal and policy landscape surrounding human germline modification. It will begin by laying the groundwork for the subsequent assessment of specific legal provisions and policies governing the modification of the human germline from basic research to clinical applications. Finally, it will reflect on the challenges and future possibilities for human germline modification in Canada.
Belgium regulates research on human embryos, including germline modification, mainly through the 2003 Law regarding Research on Embryos In Vitro and the 2007 Law regarding Medically Assisted Reproduction and the Disposition of Embryos and Gametes. It allows the creation of embryos for research when the research goal cannot be reached by research on supernumerary embryos. The lawmaker only recognizes a gradual difference between embryos created for reproduction and later used for research and embryos specifically created for research purposes. The general rule in research is that no research can be performed for eugenic goals, i.e., selection or improvement of non-pathological characteristics of the human species. Everything that is not prohibited by the law is allowed. The conclusion, supported by the parliamentary debate, is that germline genome editing is permitted for corrective purposes (meaning elimination or correction of genetic diseases), if approval of the local ethics committee and the Federal Commission on scientific research on embryos in vitro is obtained.
Often associated with urban institutions as coffeehouses and learned societies, the Enlightenment included fascination with outsiders – wild men, feral children, shipwrecked solitaries and local savages, or rustics. The long eighteenth-century theatre showcases this interest in “local savagery” in particular through a huge expansion in the number of plays set in spas, villages and country estates. These plays expand the collective vision of the nation, often celebrating the countryside as the green heart of England, the site of immemorial rights and model of social harmony. Just as frequently however, this pastoral image is threatened or subverted by Irish or labouring-class writers such as Robert Dodsley and Oliver Goldsmith, who highlight the local injustice and imperial violence that holds the rural (and national) hierarchy in place. This chapter maps rural dramaturgy from the Restoration forward to reveal these conflicting representational strategies, as Whigs and Tories fought to claim the nation’s heartland as the symbolic ground of political legitimacy and were followed by increasingly radical outliers whose view of rural society was considerably more critical.
Over the last three decades, the organized American-Jewish community has preoccupied itself with sociodemographic concerns regarding maintenance of a viable Jewish life in the United States. In this article, I study a key dimension of this preoccupation with population trends: the quantity of the Jewish population, that is, the number of Jews. I show the centrality of this dimension in shaping a cluster of anxious discourses and interventionist engagements directed toward stemming numerical decline. Analyzing this policy world in terms of a “Jewish biopolitics,” I assess how the voluntary nature of American Jewry has shaped a distinct biopolitical field, reliant on “making Jews” by both biological and cultural reproduction, enmeshing dimensions of quantity and quality. Juxtaposing this Jewish biopolitical engagement with the one exercised by the Israeli state, I flesh out broader considerations and contributions, and introduce the exploratory concept of “minority community biopolitics.” The article is grounded in an anthropological study of policy, including fieldwork, interviews, and a review of the flurry of archival and public materials related to the topic.
This study attempts to figure out the seasonality of the transmissibility of hand, foot and mouth disease (HFMD). A mathematical model was established to calculate the transmissibility based on the reported data for HFMD in Xiamen City, China from 2014 to 2018. The transmissibility was measured by effective reproduction number (Reff) in order to evaluate the seasonal characteristics of HFMD. A total of 43 659 HFMD cases were reported in Xiamen, for the period 2014 to 2018. The median of annual incidence was 221.87 per 100 000 persons (range: 167.98/100,000–283.34/100 000). The reported data had a great fitting effect with the model (R2 = 0.9212, P < 0.0001), it has been shown that there are two epidemic peaks of HFMD in Xiamen every year. Both incidence and effective reproduction number had seasonal characteristics. The peak of incidence, 1–2 months later than the effective reproduction number, occurred in Summer and Autumn, that is, June and October each year. Both the incidence and transmissibility of HFMD have obvious seasonal characteristics, and two annual epidemic peaks as well. The peak of incidence is 1–2 months later than Reff.