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Since ancient times, couples have been trying to influence the sex of their children. Following a suggestion by Aristotle, they were making love in the north wind to ensure the birth of a son and in the south wind to ensure the birth of a daughter. According to a proposal made by Galen, men were tying a string around their left testicle to make a boy and tying the right one to make a girl. In medieval times the proposed formula got even more bizarre when alchemists recommended to drink the blood of a lion and then have intercourse under a full moon to sire a son.
Choosing the sex of our children is no longer a fantasy. However, the prospect of a reliable method for sex selection has not only raised old hopes, but also new fears. Many people are concerned that it may lead to an imbalance of the sexes, most likely a preponderance of males. Such an overabundance of men and a shortage of women, some sociologists have predicted, will invariably cause an enormous rise in enforced celibacy, polyandry, homosexuality, prostitution, rape and other sexual crimes. Many feminists are similarly alarmed. Some have called the deliberate choice of a male child ‘the original sexist sin’. Others went so far as to warn us of an impending ‘gynocide’. Are these fears justified? How well are they supported by empirical evidence? And most of all: does sex selection call for a legal ban?
The contents and title of this book were inspired by a workshop held at Melbourne University in November 2005 under the auspices of the Australian Research Council Centre for Applied Philosophy and Public Ethics. The workshop brought together experts from law, medicine and philosophy. Many of those who participated are the authors of chapters in this collection.
The ‘sorting society’ expresses what many people believe will be the outcome of advances in genetic technology: a society in which gender and many characteristics of children are no longer the result of genetic luck but of deliberate selection. The book focuses on the ethical, legal and social issues raised by this technology. Is the prospect of a sorting society something that we should welcome or deplore? Do concerns about how parents or societies might exercise the choice given to them by genetic technology give us reason to restrain its creation or use, and if so how? Would a sorting society increase the freedom of parents and the wellbeing of children or would it undermine values that are central to a liberal democratic society? Would it adversely affect relationships between parents and children or the prospects for future generations?
These are questions of the most profound significance, bearing on the world in which our children and their children and grandchildren will live. Citizens as well as experts need to engage in wise reflection about the development of, use of and restrictions on genetic technology.
Many concerns have been expressed about the long-term implications of allowing women to have pre-implantation or prenatal genetic diagnostic tests for their fetus or embryo and the potential medical interventions that may follow from such tests. These interventions include implantation of only ‘unaffected’ embryos; sex selection; termination of pregnancy if a fetus is found to be affected; pre-implantation or prenatal ‘gene therapy’; and even cloning an embryo to avoid mitochondrial genetic disease, which is not avoidable by prenatal testing.
There are concerns about ‘playing God’, ‘designer babies’ and judging the ‘value’ of a baby who is chromosomally or physically abnormal. There are fears about genetic determinism. If genetic testing becomes routine, will undue weight be placed on genetic factors in assessing people's potential achievements, so that those with particular genetic traits suffer unfair discrimination? If it is possible to avoid the birth of children with genetic disorders, will pregnant women feel compelled to agree to tests, or even be penalized if they refuse and have a disabled child, for example, by having to pay higher health insurance premiums? Will the community's sympathy for people with disabilities be reduced as fewer babies are born with congenital disabilities? There are also social justice issues. Who will fund routine genetic tests? If women must pay for the tests themselves, what are the implications for equity? Could genetic tests lead to a society of ‘unequals’?
On the other hand, there are many arguments in favour of pre-implantation and prenatal genetic testing.
The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man.
Introduction
Couples (or single reproducers) have a moral obligation to strive to have disability-free children. Disability is sometimes argued to be a social construction. It is said that disability should be removed by altering social institutions and circumstances. At least in some circumstances, I argue that biopsychosocial correction of disability is needed, where disability is removed by altering our biology or psychology, or selecting our children.
The principle of Procreative Beneficence
In a previous paper, I sketched what I called the principle of Procreative Beneficence:
couples (or single reproducers) should select the child, of the possible children they could have, who is expected to have the best life, or at least as good a life as the others, based on the relevant, available information.
This principle is novel in one way. It claims that we have a good reason to select which child we have. Many people deny this. They claim we should not select our children. According to folk morality, we should accept whichever child Nature or God gives us as a gift. There is a significant distance between the principle of Procreative Beneficence and folk morality. Can Procreative Beneficence be defended?
There are many objections to this principle. I will address these. But let me first clarify this principle and give an expanded formulation.
In-vitro fertilization techniques and pre-implantation genetic diagnosis (PGD) currently allow parents to select an embryo for implantation in a woman's womb to avoid the resulting offspring suffering from, or being a carrier of, an inherited genetic disorder. In the future, it may be possible to screen and select embryos for non-disease genetic traits or predispositions. As well, some moral philosophers anticipate technologies that will enable parents to create embryos with a reduced susceptibility to disease as well as with valued non-disease characteristics such as height, intelligence, heterosexuality, impulse control, resistance to alcoholism, maternal behaviour, extraversion and athleticism, to name a few. In this chapter, I will refer to all such reproductive and genetic selection techniques as ‘reprogenetic technologies’.
If science does deliver the knowledge necessary for parents to create embryos free from disease and with desired non-disease traits and predispositions, questions arise as to whether parents would be morally obligated to use such technologies or, if no such obligations exist, whether it might still be morally permissible for them to choose to use them. Even if obligations can be founded or parental choice justified, we must ask whether society has good reason to encourage or allow untrammelled parents to use the technologies or whether some restrictions or even prohibitions may be justified.
To explore these questions, I will examine two claims.
Suppose that it becomes possible to control the genetic traits of our descendants, and thus treat them as a product which can be engineered to our liking. Employing a Kantian vocabulary, Habermas says that this is a kind of intervention which should only be exercised over things, never over persons. In The Future of Human Nature, Habermas develops a version of a common objection to genetic engineering – that it would involve treating humans as means rather than as ends. His formulation of this argument is important because he makes the novel claim that there is a somatic basis to our ethical freedom. We are embodied individuals and in order to regard ourselves as free and equal members of a community of similarly embodied individuals, we need to stand in a certain relationship to our own unchosen physical characteristics. The prospect of choosing the positive genetic characteristics of another person threatens to change the nature of that person's relation-to-self in a way that undermines his or her potential to become fully autonomous.
A number of philosophers working within the liberal tradition have argued that, for certain purposes, genetic selection and enhancement of embryos may be consistent with liberal principles. Liberal eugenics distances itself from the dark history of authoritarian, state-directed eugenics programmes, but asserts that parents' rightful freedoms entitle them to pursue some eugenic goals with respect to their children.
The deeds of present generations create favourable or unfavourable conditions for people not yet born. But our actions not only affect what they will experience in the future. We also make those who will have experiences, and we shape their capacities for thought and action. Genetic technology provides an ever-increasing power to determine what their nature and capacities will be. In discussions about the ethical implications of genetic technology and the restrictions that ought to be placed on research and application, philosophers have mostly worried about the impact of the technology on individuals. They have considered whether and how particular techniques would violate rights or have an adverse effect on the wellbeing or autonomy of individuals. In this chapter I will focus on the impact of genetic technology on intergenerational relationships. My aim is to determine whether these techniques, now or in the future, could create intergenerational injustices.
Generations and justice
In discussions of intergenerational justice several senses of generation come into play. In a family, those who count as members of the same generation are defined by their relation to their parents or by their position in a family tree. In a social sense, a generation is a group of individuals whose births fall within specified dates and who move through life together. How we set the parameters is an arbitrary matter.
Objective: To evaluate mesometrial transplantation of frozen-thawed ovarian tissue in rabbit and to choose the optimized fertilization method for oocytes retrieved from grafts by investigating the capability of oocyte fertilization and further development. Forty rabbits were divided into three groups randomly: control group, fresh tissues transplantation group and frozen-thawed tissues transplantation group. Three months after the transplantation, rabbits were stimulated with FSH and oocytes were retrieved 13 h after human chorionic gonadotropin (HCG) injection. Oocytes matured in vivo or in vitro were then fertilized by conventional in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI), followed by observation and evaluation of fertilization rate and blastocyst formation rate. Blastocytes embryos were transferred to pseudopregnancy rabbits to observe pregnancy rate and birth rate. There were no significant differences in the percentage of oocytes matured either in vivo or in vitro among the three groups. The fertilization rate, cleavage rate and blastocyst formation rate of in vivo-matured oocytes had no difference among the three groups, whether they were fertilized by IVF or ICSI. Significantly higher fertilization rates of in vitro-matured oocytes were observed with ICSI compared with IVF in each group. The blastocyst formation rate of in vitro-matured oocytes was significantly lower than that of in vivo-matured oocytes in each group. The birth rate of in vivo-matured oocytes was significantly higher than that of in vitro-matured oocytes, although the pregnancy rate was similar between them. Mesometrial transplantation of frozen-thawed ovarian tissue may provide favorable conditions for follicle development. Oocytes retrieved from mesometrial grafts can develop to the blastocyst stage and produce live offspring. ICSI can optimize the fertilization rate of in vitro-matured oocytes retrieved from grafts.
The objective of this study has been to develop a prediction equation of fat-free mass (FFM) from buffalo calves. Twenty buffaloes were fed ad libitum access at unifeed, with vitamin–mineral integration, for 14 months. Seven days before slaughtering, the animals were weighed and bioelectrical impedance measurements were collected. The data were analyzed by multiple linear regressions to evaluate the relationship between FFM and various predictor variables. Stepwise regression was used to eliminate variables that did not influence variation in the model. The value of resistance collected showed a decrease when the electrical frequency increases, while the values of reactance (Xc) increase. When using live weight (LW) and reactance at 500 and at 1000 kHz as independent variables, we obtained the best R2 Adj (0.967) and Durbin Watson statistic (2.596) that explain the prediction model (FFM = − 30.59 + 0.993LW + 0.150Xc500 − 0.123Xc1000 + 9.11). These results indicate that the use of bioelectrical impedance analysis has excellent potential as a rapid method, with minimal perturbation for the animal, to predict FFM in buffalo.
An option to increase the productivity of saline land is to graze sheep on salt-tolerant plants, which, during the summer/autumn period, can contain 20% to 25% of their dry matter as salt. This study assessed the impact of coping with high dietary salt loads on the reproductive performance of grazing ewes. From the time of artificial insemination until parturition, 2-year-old maiden Merino ewes were fed either a high-salt diet (NaCl 13% of dry matter) or control diet (NaCl 0.5% of dry matter). Pregnancy rates, lamb birth weights, milk composition and the plasma concentrations of hormones related to salt and water balance, and energy metabolism were measured. Leptin and insulin concentrations were lower (1.4 ± 0.09 v. 1.5 ± 0.12 ng/ml; (P < 0.05) and 7.2 ± 0.55 v. 8.2 ± 0.83 ng/ml; P < 0.02) in response to high-salt ingestion as was aldosterone concentration (27 ± 2.7 v. 49 ± 5.4 pg/ml; P < 0.05), presumably to achieve salt and water homeostasis. Arginine vasopressin concentration was not significantly affected by the diets, but plasma concentration of T3 differed during gestation (P < 0.02), resulting in lower concentrations in the high-salt group in the first third of gestation (1.2 ± 0.18 v. 1.3 ± 0.14 pmol/ml) and higher concentrations in the final third of gestation (0.8 ± 0.16 v. 0.6 ± 0.06 pmol/ml). T4 concentration was lower in ewes ingesting high salt for the first two-thirds of pregnancy (162 ± 8.6 v. 212 ± 13 ng/ml; P < 0.001). No substantial effects of high salt ingestion on pregnancy rates, lamb birth weights or milk composition were detected.
The time at pasture of dairy cows is often restricted in the context of extending the grazing season in autumn or at the end of winter. The objective of our study was to evaluate the effects of a restriction of time at pasture on milk production, herbage intake and feeding behaviour in dairy cows according to feeding regime. The four treatments consisted of 4 h or 8 h of time at pasture per day tested under two feeding regimes combining rate of supplementation and herbage allowance: either a high rate of supplementation (10 kg dry matter (DM) of a maize silage-soya bean meal mixture in the ratio 87 : 13 on a % DM basis) with a low herbage allowance (6 kg DM/cow per day above 5 cm), or a low rate of supplementation (5 kg DM of the same supplement) with a high herbage allowance (11 kg DM/cow per day). The study was carried out according to a 4 × 4 Latin square design with four 2-week periods, with 48 mid-lactation Holstein cows. The cows in the 4-h treatment had access to pasture from 0900 h to 1300 h and those in the 8-h treatment from 0900 h to 1700 h. The supplement was given at 1830 h. When time at pasture was reduced from 8 h to 4 h per day, herbage intake decreased (9.9 v. 8.1 kg DM, P < 0.001), along with a fall in milk production (22.3 v. 21.2 kg, P < 0.001) and milk protein concentration (30.1 v. 29.6 g/kg, P < 0.001), while milk fat concentration increased (39.4 v. 39.9 g/kg, P < 0.05). The effect of time at pasture on milk production was slightly more marked on the low-supplement feeding regime (interaction P < 0.06). Reducing time at pasture by 4 h led to a sharp decrease in grazing time (327 v. 209 min, P < 0.001), but strongly increased the pasture intake rate (31 v. 39 g DM/min, P < 0.001) and the proportion of time spent grazing (0.68 v. 0.87, P < 0.001). Cows showed a stronger motivation for grazing when receiving the low-supplement feeding regime. In conclusion, we showed that reducing time at pasture from 8 to 4 h for cows receiving 5 to 10 kg DM of a maize silage-based supplement decreased moderately milk production and herbage intake, because of the capacity for behavioural adaptation by the grazing dairy cows.
This study was done to evaluate the effects of two sublethal doses of gossypol (4 and 20 mg/kg of BW, every other day) on some amino and fatty acid concentrations in male rabbit seminal plasma. Rabbits were chosen as an experimental animal owing to the fact that they are excellent model for reproductive toxicological effects. The experiment lasted 16 weeks and included two periods: a treatment period (first 8 weeks) where the animals were given the tested product, and a recovery period (second 8 weeks) where all drugs were withdrawn. Results showed that total amino acids (TAA), total essential amino acids (EAA), total non-essential amino acids (non-EAA) and EAA/non-EAA ratio were decreased in a dose-dependent manner during gossypol treatment. The deleterious effect on TAA concentrations was mainly due to the reduction in total EAA. However, these concentrations regained their normal values after gossypol cessation. Basic, acidic, neutral amino acids and basic/acidic amino acids ratio decreased in a dose-dependent manner by gossypol treatment. Additionally, gossypol administration caused decreases in total unsaturated fatty acids (USFA) and increases in total saturated fatty acids (SFA) and the SFA/USFA ratio in a dose-dependent manner. During the recovery period, total SFA and USFA showed significant reduction and significant increase, respectively, after gossypol withdrawal. In conclusion, gossypol administration affected rabbit seminal plasma concentrations of amino and fatty acids in a dose-dependant manner. Gossypol reduced TAA, total EAA and total non-EAA. Additionally, gossypol caused decreases in total USFA and increases in total SFA. These deleterious effects were associated with poor-quality semen observed in our previous studies.
Golden hamsters of one common laboratory strain had a high incidence of hydrocephalus internus. When a severity score of hydrocephalus was used, a major autosomal recessive locus could be identified. However, when a binary score (hydrocephalus, no hydrocephalus) was used, no such major locus could be detected and results of test matings were not consistent with Mendelian inheritance. Golden hamsters with severe forms of hydrocephalus had a dorsally compressed and ventrally intact hippocampus. Implications for the behavior and well-being of affected hamsters are unknown but researchers using this strain should be aware of the likely presence of hydrocephalus.
This experiment was designed to investigate the effects of meal-time feeding and protein restriction on performance, gait score (GS) and carcass and bone traits in broilers. A total of 420 1-day-old chicks were wing banded and randomly distributed into 21 pens with 20 chicks each. At 7 days of age, chicks were weighed and randomly assigned to one of the three treatments: (1) control (C) feed (23.02% crude protein (CP)) was available ad libitum; (2) meal-time feeding (MF); control feed was available from 0100 to 0900 h and from 1500 to 2300 h. Food was withdrawn from 0900 to 1500 h and whole wheat (10 g/bird per day) was dispersed on the floor from 7 to 21 days; and (3) low-protein (LP) diet (19.71% CP) was fed to the chicks from 7 to 21 days. All of the groups were fed ad libitum from 1 to 7 days of age and from 21 to 45 days of age with a standard commercial diet. Individual body weight was measured on days 7, 21 and 45. Feed consumption was measured from 7 to 21 days and from 21 to 45 days. Forty-two chicks were humanly slaughtered and eviscerated for bone evaluation, on days 21 and 45. Also carcass characteristics were determined on day 45. Control group body weight was significantly higher (P < 0.05) at 21 and 45 days of age than the MF and LP groups, which did not differ. Feed intake was reduced by meal-time feeding and LP diet (P < 0.01). Feed efficiency was the best in the MF group during the period of 21 to 45 days of age (P < 0.01). In the control group, shank was significantly longer than that of the LP group and tibia breaking strength was higher than that of the MF group at 21 days (P < 0.05). However, shank width, tibia wet weight and tibia mid-diaphysis ash percentage of the MF group were significantly lower than those of the C and LP groups at 21 days of age (P < 0.05). GS, shank and carcass and tibia bone traits on day 45 were not significant among groups. No compensatory growth and walking ability improvement were observed at 45 days of age for broilers fed with MF and LP between 7 and 21 days of age.
The aim of the study was to analyse the genetic background of different traits to characterise the maternal behaviour of sows and to evaluate the relationship to different causes of piglet losses – increasing piglet survival due to higher maternal abilities of the sow. A total of 1538 purebred litters from 943 German Landrace sows in the year 2004 were available for data analysis. Around 13 971 individually earmarked piglets were included in the analyses. Maternal abilities were characterised through the sow’s reaction to the separation from her litter during the first 24 h after farrowing, and on day 21 of lactation, the reaction towards the playback of a piglet’s distress call and the reaction towards an unknown noise (music). In 1220 of these litters, the sows were also scored for aggressiveness in the group when regrouped before entering the farrowing crates. To describe fertility, the number of piglets born alive, stillborn piglets, number of piglets born in total and the individual birth weight were utilised. Different causes of piglet losses were evaluated as binary traits of the dam with survival rate, different definitions for crushing by the sow, being underweight and runts. The heritability for being aggressive in the group was h2 = 0.32 and for the behaviour traits during lactation, the heritabilities ranged from h2 = 0.06 to 0.14. The genetic correlations showed that more-reactive sows had fewer piglet losses.
The research was carried out to evaluate the effect of different α-tocopherol concentrations in lamb meat on oxidative stability during storage in high-oxygen atmosphere. Thirty-six lambs were randomly distributed to four groups and given diets containing four levels of vitamin E (20, 270, 520 and 1020 mg vitamin E/kg feed) from an initial weight of 13.2 ± 0.5 kg to a slaughter weight of 26.2 ± 0.3 kg. Supplementation of the diet with vitamin E increased (P < 0.001) the concentration of α-tocopherol in the meat and concentrations were obtained in the 0.46 to 4.14 mg/kg meat range. Broken-line analysis of data indicated a target dietary vitamin E supplementation of 287 mg/kg feed, which corresponded with a concentration of 2.26 mg α-tocopherol/kg meat. α-Tocopherol in meat was highly correlated with the oxidation of lipids and pigments. Broken-line analysis of data indicated the target α-tocopherol concentration in lamb for improved protection against lipid and pigment oxidation during 14, 21 and 28 days of storage in high-oxygen atmosphere was in the range 1.87 to 2.37 mg/kg meat. These concentrations of α-tocopherol in the meat made it possible to maintain the indicator values of lipid and pigment oxidation below the values considered in the bibliography as unacceptable to the consumer.
Two trials were performed to assess changes in the physicochemical properties of precisely processed (micronised v. extruded) wheats, prior to inclusion in piglet diets. The in vitro data obtained were subsequently related to biological responses of newly weaned piglets over 14 days. The effects of the severity of micronisation (Trial 1) or extrusion (Trial 2) on the nutritional value of two wheats (varying in endosperm texture) were examined. Extrusion, in contrast to micronisation, drastically disrupted the structural properties of wheat starch granules through melting of crystallites and macromolecular degradation of starch polysaccharides. These structural changes strongly improved the hydration characteristics of starch and its digestibility. The amount of starch digested in vitro was approximately 0.20, 0.70 and 0.90 for the unprocessed, micronised and extruded samples, respectively. This enhanced in vitro digestibility correlated well with, and helped to explain, the significant improvement in the apparent digestibility of starch at both the 0.5 region (mean coefficients for extruded wheat were 0.869 and 0.959 v. raw 0.392; P = 0.017) and 0.75 region (extruded 0.973 v. raw 0.809; P = 0.009) of the small intestine, when compared with piglets fed an unprocessed wheat diet. Extrusion and, to a lesser extent, micronisation lessened the reduction in apparent starch digestibility on day 4 post-weaning, typically seen at the 0.5 intestinal region in piglets fed an unprocessed wheat diet. Processing variables influenced both in vitro and in vivo data, with for instance, a positive relationship between specific mechanical energy (SME) input during extrusion and starch digestibility at the 0.5 region. The higher digestibility coefficient observed at the 0.5 region for the high SME diet suggests enhanced digestion and more rapid release of starch. However, it remains to be seen whether a diet containing rapidly digestible, as opposed to slowly digestible, starch is more beneficial for piglets. This rate of starch breakdown in the piglet is an important finding, which may have implications in helping to alleviate the post-weaning growth check, particularly in the absence of in-feed antibiotic growth promoters. Processing did not appear to offer any benefit over unprocessed wheat with regard to daily live-weight gain or the apparent digestibility of nitrogen in the small intestine over the 14-day period. Based on the enhanced in vivo starch digestibility, performance might be improved over a longer period, although future studies are required to confirm this. Precise processing variables for raw materials must be stated in all animal trials.