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PubMed1995

The reproductive and neural toxicities of acrylamide and three analogues in Swiss mice, evaluated using the continuous breeding protocol.

Acrylamide is a known genetic, reproductive, and neural toxicant, although it is not known if one effect is predominant. The toxicities of several structural analogues of acrylamide have been incompletely characterized, and the relative sensitivity of the second generation is not known. The present studies were designed to explore the relationship between neurotoxicity and reproductive toxicity, to further characterize the toxicities of three acrylamide analogues, and to evaluate the relative sensitivity of a second generation to these compounds. For the F0 generation, male and female Swiss CD-1 mice were provided drinking water containing acrylamide (ACR; 3, 10, 30 ppm), N,N'-methylenebisacrylamide (MBA; 10, 30, 60 ppm), N-(hydroxymethyl)acrylamide (HMA; 60, 180, 360 ppm), or methacrylamide (MACR; 24, 80, 240 ppm) during and after a 14-week cohabitation. The last litter was reared and dosed after weaning until mating at 74 +/- 10 days of age with the same level of compound given to the parents Neurotoxicity was assessed at several times in both generations by measuring forelimb and hindlimb grip strength. In the F0 generation, ACR caused an 11% decrease in pup number without measurable neurotoxicity; female fertility was not affected. Although both generations consumed the same amount of ACR, there were larger changes in the fertility-related endpoints in the F1 mice than in the F0's, with no concomitant change in organ weights or sperm parameters. In F0 mice, MBA reduced the number of live pups and their adjusted weight, with no neurotoxicity and no change in F0 female reproduction. MBA caused greater adverse effects in the second generation, concomitant with increased consumption. In the F0 generation, HMA caused the largest decrease in pup number during cohabitation (26%) together with a small effect on grip strength. Female reproduction was not affected. The second generation consumed more HMA and showed slightly greater toxic effects. In both generations, MACR was negative for both neurotoxicity and reproductive toxicity. Dominant-lethal studies showed that the fertility effects for ACR, MBA, and HMA could be explained by a male-mediated increase in postimplantation loss. These studies found that dominant lethality occurred without structural effects on the reproductive system in the presence of only minor effects on grip strength and without detectable neural histopathology. Female reproduction was not significantly affected by these compounds at the doses used. Thus, these data confirm the male as the affected gender and that the reproductive toxicity was greater than motoneuron toxicity when measured as grip strength.

Acrylamide↗

PubMed1999

Effects of photoperiod and reproductive responsiveness on pituitary sensitivity to GnRH in male prairie voles (Microtus ochrogaster).

In order to promote survival and reproductive success, many nontropical rodents inhibit reproduction well in advance of winter in response to decreasing day lengths. Male prairie voles (Microtus ochrogaster), small temperate zone rodents, vary in their reproductive response to photoperiod. Some male voles undergo complete gonadal regression when housed in short days (responders) whereas others fail to inhibit reproduction when exposed to short (i. e., <12 h light/day) day lengths (nonresponders). Previous research has shown that phenotypic variation in reproductive response is reflected at the level of the hypothalamic gonadotropin-releasing hormone (GnRH) neuronal system. The present study sought to determine if photoperiod or reproductive condition alters pituitary responsiveness to a GnRH challenge. Animals were housed in either long (LD 16:8) or short (LD 8:16) photoperiods for 10 weeks. Subsequently, short-day voles were separated into responders and nonresponders based on testicular size. To reduce the influence of endogenous testosterone on luteinizing hormone concentrations, half of the animals in each group were castrated. All animals were injected (i.p.) with either 100 or 50 ng of GnRH and a blood sample was collected after 15 min. Although castration resulted in a significant increase in LH concentrations (P < 0.05), neither photoperiod nor reproductive condition affected LH concentrations in response to a GnRH challenge (P > 0.05). Taken together, these data support the hypothesis that short photoperiods lead to reproductive inhibition by acting at the level of the hypothalamus rather than the pituitary.

Animals↗

PubMed2000

Leptin and metabolic control of reproduction.

Leptin treatment prevents the effects of fasting on reproductive processes in a variety of species. The mechanisms that underlie these effects have not been elucidated. Progress in this area of research might be facilitated by viewing reproductive processes in relation to mechanisms that maintain fuel homeostasis. Reproduction, food intake, and fuel partitioning can be viewed as homeostatic responses controlled by a sensory system that monitors metabolic signals. These signals are generated by changes in intracellular metabolic fuel availability and oxidation rather than by changes in the amount of body fat or by changes in any aspect of body composition. Leptin might be viewed as either a mediator or as a modulator of the intracellular metabolic signal. Consistent with its purported action as a mediator of the metabolic signal, leptin synthesis and secretion are influenced acutely by changes in metabolic fuel availability, and these changes might lead to changes in reproductive function. The effects of leptin treatment on reproduction are blocked by treatments that inhibit intracellular fuel oxidation. Metabolic signals that inhibit reproduction in leptin-treated animals might act via neural pathways that are independent of leptin's action. Alternatively, both leptin and metabolic inhibitors might interact at the level of intracellular fuel oxidation. In keeping with the possibility that leptin modulates the metabolic signal, leptin treatment increases fuel availability, uptake, and oxidation in particular tissues. Leptin might affect reproduction indirectly by altering fuel oxidation or other peripheral processes such as gastric emptying. Reproductive processes are among the most energetically expensive in the female repertoire. Because leptin increases energy expenditure while simultaneously inhibiting energy intake, it may have limited use as a long-term treatment for infertility.

Adipose Tissue↗

PubMed2005

Reproduction elevates the corticosterone stress response in common fruit bats.

Changes in reproductive state or the environment may affect the sensitivity of the hypothalamic-pituitary-andrenal (HPA) axis. However, little is known about the dynamics of the resulting corticosteroid stress response, in particular in tropical mammals. In this study, we address the modulation of corticosterone release in response to different reproductive conditions and seasonality in 326 free-living common fruit-eating bats (Artibeus jamaicensis) on Barro Colorado Island in Panama during dry and wet seasons. We present strong evidence that stress sensitivity is primarily modulated by reproductive condition. In reproductively active females, corticosterone increases were more rapid and reached higher levels, but also decreased significantly faster than in inactive females. The corticosterone response was weaker in reproducing males than in females and delayed compared to non-reproductive males. Testes volume in reproductively active males was negatively correlated with corticosterone concentrations. Our findings suggest differentiated dynamics in the corticosterone stress response between sexes, potentially reflecting conflicting ecological demands. In females, a strong acute corticosterone response may represent high stress- and risk-sensitivity that facilitates escape and thus helps to protect reproduction. In males, suppression during reproductive activity could reflect lowered stress sensitivity to avoid chronically elevated corticosterone levels in times of frequent aggressive and therefore costly inter-male encounters.

Animals↗

PubMed2006

Spousal abuse against women and its consequences on reproductive health: a study in the urban slums in Bangladesh.

OBJECTIVES: Spousal violence is common and results in costly problems both for society and for the reproductive health of women. Despite the recognition that violence may be associated with serious consequences for women's reproductive health, our understanding of the relationship between the two remains limited. In this study, we assessed the association between spousal violence and women's reproductive health. METHODS: Data from an interviewer-administered questionnaire assessing socioeconomic, demographic, behavioral profiles, and spousal violence-related information was collected from 496 women. Subjects were chosen from eight randomly selected urban slums from four metropolitan cities. RESULTS: Spousal violence was significantly higher amongst the group of less educated women who had been in several marriages; indicating that the social and behavioral traits of women act as catalysts for spousal violence. Abusive husbands also had been married several times and were more likely to be addicted to alcohol or drugs. This demonstrates that the behavioral traits of husbands were also responsible for spousal violence. Spousal violence injuries adversely affect the health and well-being of women. More than three-quarters of physically violated women suffered injuries as a result of this violence. About 50% of these injuries were minor and about 10% serious. Sexual violence adversely affected women's health; more than 80% of sexually violated women complained of pelvic pain, more than 50% reported reproductive tract infections, and more than 50% reported symptoms of irritable bowel syndrome. Abused women suffered from gynecological problems at the time of pregnancy significantly more than non-abused women (p<0.05) and abused women suffered from reproductive tract infections significantly more than non-abused women (p<0.01). Abusive husbands suffered from sexually transmitted diseases (STD) significantly more than non-abusive husbands (p<0.05). Abused women used contraception significantly less than non-abused women (p<0.01). Logistic regression analysis suggested that spousal violence was the most important contributing factor for reproductive health problems in women. CONCLUSIONS: The findings of this study may enhance our understanding of the impact of spousal violence against women and their reproductive health and therefore highlight the importance of spousal violence prevention measures. Increasing the awareness and understanding of the relationship between violence against women and reproductive health could be achieved if lawyers, researchers, clinicians, practitioners, and government workers from multiple disciplines and agencies worked together.

Adult↗

PubMed1995

Ideal residency curriculum in reproductive endocrinology and infertility.

OBJECTIVE: Knowledge in reproductive endocrinology and infertility is fundamental to the delivery of quality women's health care. In 1991, the American Fertility Society formed a resident education committee to gather data on the current status of reproductive endocrinology and infertility training and develop an ideal curriculum. METHODS: Program directors and reproductive endocrinology and infertility faculty from 288 residencies in obstetrics and gynecology were surveyed about training in reproductive endocrinology and infertility; 257 (89%) of the program directors (survey I) and 203 (82%) of the reproductive endocrinology and infertility faculty (survey II) responded. An ideal curriculum has been developed from consensus discussions, review of survey data, and polling of experienced educators. The curriculum was reviewed and approved by the board of directors of both the Society for Reproductive Endocrinologists and the American Fertility Society. RESULTS: The curriculum is divided into subject matter and therapeutics, which are prioritized into three levels of knowledge: critical core curriculum, less critical material, and material with which residents should have familiarity and general knowledge. In addition, other recommendations and suggestions are made regarding the number of rotations, duration of rotations, and teaching methods. CONCLUSION: The ideal curriculum may serve as a guide to assist program directors in the formulation of the most effective residency training in reproductive endocrinology and infertility. The curriculum can help prioritize what should be taught and where an emphasis can be placed. There is not enough time or resources to teach residents all aspects of reproductive endocrinology and infertility.

Curriculum↗

PubMed1993

Sites of female reproductive vulnerability: implications for testing and risk assessment.

All reproductive toxicity testing, whether in vivo or in vitro, should be conducted with consideration of the ultimate use of the data for reproductive risk assessment and the protection of human reproductive health. In this review selected sites of vulnerability in the female reproductive system are identified. These sites of female reproductive vulnerability may be utilized for in vitro toxicity testing assays, and the data from assays may be employed in the hazard identification and hazard characterization steps necessary for reproductive risk assessment. Using biomarkers of female reproductive function derived from in vitro toxicity testing it is possible to define functions that characterize female fecundity. These characterizations of female fecundity may be used to quantitate reproductive risk in human populations.

Animals↗

PubMed2004

International training programs in reproductive sciences for conservation of Latin American felids.

Survival of the ten non-domestic felid species endemic to Latin America is imperiled by habitat loss, poaching and poor captive management. Over the past 10 years, conservation of these felids has been the primary focus of a reproductive research and training program conducted in Brazil, Mexico, and the USA. The objectives of this program were to: (1) provide intensive training in reproductive sciences to Latin American scientists, (2) conduct collaborative studies investigating basic and applied reproduction in endangered felids, and (3) establish a highly-trained scientific cohort to conduct independent conservation-based research. Four formal training courses, consisting of didactic lectures and hands-on instruction in research techniques, including semen collection, sperm cryopreservation and laparoscopic artificial insemination (AI), were taught in Brazil and Mexico between 1995 and 1998. Several of these scientists received further training in conducting fecal hormone analysis in the USA, and a number of research studies, many in collaboration with American scientists, were initiated in Latin American felids. Research findings have characterized basal reproductive traits in several felid species, including ocelots, margay, tigrinas and jaguars, and established that Latin American felids exhibit only minimal seasonal variation in most reproductive traits. Other studies have explored the impact of acute and chronic stressors on adrenocortical activity and demonstrated the importance of environmental enrichment in captivity, especially in small felids. Additional research has examined ovarian and immunological responsiveness of Latin American felids to exogenous gonadotropins and assessed the impact of nutrition on sperm production and oocyte quality. Applied reproductive studies have investigated sperm cryopreservation in both captive and wild felid populations and demonstrated the production of viable offspring in ocelots and tigrinas following laparoscopic AI. Ongoing studies are investigating the potential of in vitro fertilization (IVF), embryo cryopreservation and embryo transfer for genetic management of ocelots and tigrinas. To date, over 75 Brazilian ocelot and 50 tigrina IVF embryos have been cryopreserved and two pregnancies have been established in ocelots following transfer of frozen-thawed embryos. Findings from these studies are helping to improve husbandry, population management, and breeding of Latin American felids in captivity. Continued advances in assisted reproduction eventually may provide an alternative route for exchanging genetic material among Latin American felid populations. Most importantly, this collaborative program has been essential for building scientific capacity, within Brazil and Mexico, in establishing a core group of highly-trained reproductive biologists that will continue applying their new knowledge and skills to the conservation of Latin American felids.

Animals↗

PubMed2005

Susceptibility of reproduction in female pigs to impairment by stress or elevation of cortisol.

It is generally agreed that stress can impair reproduction. Furthermore, it is often thought that cortisol, which is secreted during stress as a result of activation of the hypothalamo-pituitary adrenal axis, is associated with this stress-induced impairment of reproduction. It has been hypothesized that reproduction in females is particularly susceptible to disruption by acute stress during the series of endocrine events that induce estrus and ovulation. Nevertheless, we found no support for this conjecture when we subjected female pigs to repeated acute stress or repeated acute elevation of cortisol during the period leading up to estrus and ovulation. Conversely, studies have demonstrated that prolonged stress and sustained elevation of cortisol can disrupt reproductive processes in female pigs. Nevertheless, in each study that demonstrated this effect, there were some animals subjected to the prolonged stressor or the sustained elevation of cortisol in which the reproductive parameters that were measured were not affected by the treatment. We propose that reproduction in female pigs is resistant to the effects of acute or repeated acute stress or acute or repeated acute elevation of cortisol even if these occur during the series of endocrine events that induce estrus and ovulation. Furthermore, while reproductive processes in some individuals are compromised, reproduction in a proportion of female pigs appears to be resistant to the effects of prolonged stress or sustained elevation of cortisol.

Animals↗

PubMed2005

Control of reproductive processes by growth hormone: extra- and intracellular mechanisms.

Recent data on the association between growth hormone (GH) and male and female reproductive processes, as well as the effects of GH on these processes and on some reproductive and non-reproductive disorders, and possible extra- and intracellular mediators of its action are reviewed. The available data suggest that GH is an important endocrine and autocrine/paracrine regulator of reproduction. It controls proliferation, apoptosis, growth and differentiation and the secretory and generative activities of different reproductive organs. It also regulates their response to gonadotrophin-releasing hormone (GnRH) and gonadotropins. Despite the effects of GH on the IGF/IGFBP (insulin-like growth factor binding protein) system, oxytocin, steroids, activin, gonadotropin and gonadotropin receptors, the majority of GH's actions on the reproductive processes are probably mediated not by these substances but by specific GH receptors acting through cAMP/protein kinase A, protein kinase G, tyrosine kinase-, MAP kinase and CDC2 kinase-dependent intracellular mechanisms. Although GH treatments can increase the risk of some reproductive and non-reproductive disorders, they may be useful in improving gonadal function, inducing superovulation and in embryo production.

Animals↗

PubMed2006

Sociosexual behavior, male mating tactics, and the reproductive cycle of giraffe Giraffa camelopardalis.

Female distribution exerts a major impact on male mating tactics. Giraffe cows have a reproductive cycle, and a social system, that should favor a male roaming reproductive tactic. We conducted a 2-year study of female Rothschild's giraffe (G. c. rothschildi) reproductive endocrinology in order to characterize attributes of the reproductive cycle and investigate how female endocrine and behavioral cues influence mating activity. We used non-invasive fecal steroid methods to determine reproductive state among females residing in a herd in a large outdoor enclosure. We found that females had an estrous cycle of 14.7 days and that they regularly had multiple ovarian cycles prior to conception. Adult males were more likely to associate with, and sexually investigate, females when they were cycling than when they were either pregnant or acyclic. During the estrous cycle, male-female proximity and sociosexual behavior were more pronounced during the probable fertile phase than the rest of the cycle. Sexual activity between giraffe coincided with the periovulatory period, with male interest in females peaking during the fertile window in the absence of proceptive behavior by females. We conclude that males detect reliable cues revealing female reproductive status and partition their reproductive effort in response to such cues. We propose that male giraffe adopt a roaming reproductive strategy with their large size, enabling them to search for and mate guard fertile females while minimizing metabolic costs.

Animals↗

PubMed1992

Cytokines--involvement in reproduction.

OBJECTIVE: To relay the current knowledge on the interaction between the immune and reproductive systems that results from sharing certain lymphohematopoietic cytokines and their receptors. DATA IDENTIFICATION: Major studies related to this topic have been identified through MEDLINE searches and through the published literature. STUDY SELECTION: Those that have reported on the role of cytokines in the neuroendocrine events of reproduction, ovarian function, placenta, and the developing embryo. RESULTS: The field of growth factor and cytokines and their effects on reproduction is a rapidly growing new area of investigation. Immune cells and related cytokines have been shown to affect the neuroendocrine events of reproduction, ovarian function, placenta, and the developing embryo. Furthermore, it is now becoming apparent that these relationships are reciprocal in that the different cellular components of the neuroendocrine and reproductive systems and the developing embryo can modulate the production of cytokine by the immune system and can also produce certain cytokines. The presence of lymphocytes and macrophages in the female reproductive system, together with the fact that these cells may secrete soluble factors influencing embryo development and trophoblast growth, might suggest that cytokines may play a fundamental role in the mechanisms of immunological reproductive failure. In addition, different mixtures of these mediators, generated by immune cells, the developing embryo, or other maternal cells, may modulate the fine tuning of these activities. CONCLUSIONS: Current knowledge indicates a close interaction between the immune and reproductive functions. Further understanding of these interactions may lead to new concepts in fertility regulation.

Animals↗

PubMed2003

Stress, reproduction, and adrenocortical modulation in amphibians and reptiles.

While the hypothalamo-pituitary-adrenocortical (HPA) response to stress appears to be conserved in vertebrates, the manner in which it is activated and its actions vary. We examine two trends in the stress biology literature that have been addressed in amphibian and reptilian species: (1). variable interactions among stress, corticosterone, and reproduction and (2). adrenocortical modulation. In the first topic we examine context-dependent interactions among stress, corticosterone, and reproduction. An increasing number of studies report positive associations between reproduction and corticosterone that contradict the generalization that stress inhibits reproduction. Moderately elevated levels of stress hormones appear to facilitate reproduction by mobilizing energy stores. In contrast, pronounced activation of the HPA axis and extremely elevated levels of stress hormones appear to inhibit reproduction. Much of these contrasting effects of stress and reproduction can be explained by expanding the Energetics-Hormone Vocalization Model, proposed for anuran calling behavior, to other taxa. In the second topic, a number of amphibians and reptiles modulate their HPA stress response. Adrenocortical modulation can occur at multiple levels and due to a variety of factors. However, we have little information as to the physiological basis for the variability. We suggest that several ecologically based ideas, such as variability in the length of the breeding season and lifetime reproductive opportunities, can be used to explain the utility of adrenocortical modulation in these taxa.

Adrenal Cortex↗

PubMed1999

Role of growth hormone and prolactin in the control of reproduction: what are we learning from transgenic and knock-out animals?

Growth hormone (GH), insulin-like growth factor (IGF-I), and prolactin (PRL) can influence various aspects of reproductive functions in both females and males. However, the physiological role of PRL and the GH-IGF-I axis in the control of reproduction has been difficult to define, and the recent availability of knock-out (KO) animals allows re-examination of this issue. PRL-receptor (R)-KO and PRL-KO females are sterile because of luteal failure. In addition, these mice have severe deficits in the development of oocytes and early embryos. However, male fertility is not affected in the PRL-KO and in most of the PRL-R-KO animals. IGF-KO animals have an infantile reproductive system and are sterile. GH-R-KO mice can reproduce, but their breeding performance is reduced, particularly in females. These data indicate that IGF-I signaling is required for normal reproductive development and confirm the requirement for PRL for fertility in the female mouse. GH resistance leads to quantitative deficits in reproductive development and functions, but does not preclude fertility in either sex. We suspect that PRL and the GH-IGF-I axis provide partially overlapping (redundant) regulatory inputs to the hypothalamic-pituitary-gonadal axis, and consequently, targeted disruption of either signaling pathway has relatively mild consequences on many functions related to reproduction. Overexpression of heterologous or homologous GH in transgenic animals can lead to severe reproductive deficits, including female sterility in some of the lines. Studies in GH transgenics should allow the identification of mechanisms that mediate the effects of chronic overexposure to GH on reproduction.

Animals↗

PubMed2001

Alterations of physiological energetics, growth and reproduction of Daphnia magna under toxicant stress.

The study investigates the relationship between changes in physiological energetics of organisms and alterations of growth, development and reproduction of Daphnia magna. Groups of primiparous daphnids were subjected to 8-day exposures to the heavy metals cadmium and copper or to the cationic surfactant, cetyltrimethylammonium bromide (CTAB). Energetic alterations were estimated from the measurement of oxygen consumption and feeding activity which was performed during the last 3 days of the exposure period and from the calculation of simplified carbon balances. The physiological effects were compared to effects on organismal growth and reproduction as obtained from 17-day exposure experiments. Toxicant exposure reduced weight and body length of daphnids indicating an impaired growth rate, but effects on total metabolic costs measured as weight-specific oxygen consumption could not be detected. Net carbon gain of individuals decreased in a concentration-dependent way for the tested chemicals reflecting effects on biomass of daphnids. In the case of cadmium and copper, reproduction ( summation operatormx: number of offspring per female of age x born during the time interval x-1 to x, summarised over the entire exposure period) and the estimate for the intrinsic rate of natural increase, derived from the 17-day exposure-experiment, were affected at concentrations comparable to the effect levels as observed for growth. In the case of copper, the concentrations affecting growth and reproduction were close to the 17-day LC(50) value. CTAB caused a reduction in body length of primiparous daphnids whereas a decrease in the reproductive performance was not apparent. In conclusion, the chemicals did not change metabolic costs of exposed daphnids as it would be expected as a consequence of resistance or repair mechanisms, however, they induced alterations of SFG, growth, reproduction and intrinsic rate of natural increase. These alterations were chemical-specific. The fact that toxicant-related effects on growth and reproduction could not be linked to an elevated metabolic rate of daphnids may indicate that demand side effects occurred early during exposure - before the start of respirometric measurements - or that effects on growth were caused by an altered energy uptake. The results illustrate the importance of trade-off processes in regulating the distribution of energy among growth and reproduction of daphnids.

Animals↗

PubMedDate not supplied

Use of animal models for detecting specific alterations in reproduction.

Conventional tests of reproductive toxicity may fail to detect the effects of some agents altering reproductive functions in the male or female. A valid study of reproductive toxicity must be based on a sound understanding of the underlying reproductive physiology, use of sensitive and precise analytical methods, a powerful experimental design, and evaluation of multiple criteria in both the male and female. Potential sites and mechanisms of action of an agent affecting reproduction were considered together with approaches for tests that might be used. Development of new in vitro tests, based on procedures used for probing reproductive physiology, would be desirable. Procedures for detecting alterations in male reproductive function using animal models were considered in detail. For example, spermatogenesis is a long process and a toxic agent may alter functionality of a testicular cell type several days or weeks before this toxicity is detectable as a change in spermatogenesis. Several weeks or months may pass before a detectable change in semen occurs. Therefore, tests utilizing appropriate animal models should have a duration that is six times the duration of one cycle of the seminiferous epithelium. Evaluations of male reproductive function would be enhanced by including determinations of testicular spermatid reserves, selected simple but precise and meaningful quantitative evaluations of testicular histology, determination of the number of sperm within the distal half of the epididymis, evaluation of the progressive motility and morphology of sperm from the distal end of the epididymis, and measurement of the concentration of follicle stimulating hormone in blood. For rabbits, longitudinal analyses of seminal quality are important.

Abnormalities, Drug-Induced↗

PubMed2002

Reproductive rights and the state in Serbia and Croatia.

The global reproductive rights movement arose in the late 1980s and early 1990s as a challenge to the population control paradigm that has dominated family planning policy for almost half a century. The essence of the challenge is to place women into the center of population discussions as subjects, not objects of policy, and to reorient family planning and health programs toward meeting the broad reproductive health needs of individuals, rather than the narrow population control objectives of states. Reproductive rights advocates argue that the use of family planning programs for developmentalist-oriented population control objectives is illegimate, and inevitably relegates women to the status of depersonalized policy "targets". The cases of Croatia and Serbia, the two dominant partners in the former Federal Republic of Yugoslavia, offer interesting twists on these reproductive rights issues. In Croatia and Serbia, unlike in many nations, the governments are deliberately seeking to increase rather than decrease fertility levels. Moreover, the objective concerns identity politics, more so than development: the governments have encouraged increased fertility to safeguard the survival of their nations and to strengthen national power amidst threatening internal and external environments of ethnic conflict. In this paper, we examine the dynamics of pro-natalist fertility policy in Croatia and Serbia. We do so with a view to explaining why, despite similarities, the two have followed divergent paths. While reproductive rights violations have occurred in both nations, they have been markedly higher in Serbia than Croatia. To explain this divergence we look at a series of sociopolitical factors, including the space available for groups to mobilize in each political system; the degree of nationalistic extremism present in the discourse of central political leaders; and perceptions of threats and opportunities in external geopolitical environments. In conducting this analysis we seek to drive home the point that a nation's reproductive rights situation and prospects cannot be understood divorced from its sociopolitical context. We also raise an additional impetus for promoting the reproductive rights agenda--one largely unexplored in the family planning literature-that emerges from low fertility nations facing identity issues. Women's bodies must be protected not only against those states seeking to use their reproductive capacities for developmentalist-oriented fertility control, but also against those wanting their bodies for nationalistic-oriented fertility promotion.

Authoritarianism↗

PubMed2000

Epidemiology of reproductive performance in dairy cows.

The objectives of this presentation are to review results of our previous and on-going research with respect to the risk factors and consequences of poor reproductive performance in dairy cows, and to develop an economic framework to optimize decisions related to dairy cow reproductive performance. To make profitable breeding and replacement decisions, the farmer must account for factors including age, production level, lactation stage, pregnancy status, and disease history of the cows in the herd. Establishing the interrelationships among disease, milk yield, reproduction, and herd management is necessary for developing a decision model for disease treatment, insemination, and replacement. The data for the studies reviewed in this presentation incorporate health, production, and management components from Holsteins in the Northeast USA and Ayrshires from Finland. Data were analyzed using the Cornell Theory Center Supercomputer. The effect of risk factors on reproductive disorders was modeled with logistic regression, and on conception, insemination, and culling with survival analysis. The effect of reproductive disorders on milk yield was analyzed with mixed models. Economic optimization of reproductive performance was done with dynamic programming (DP). High milk yield, high parity, and calving in winter were risk factors for several reproductive disorders. These disorders, in turn, delayed insemination and conception in dairy cows, and some of them increased the risk of culling. Dystocia, retained placenta, and early metritis led to a short-term drop in milk production. High milk yield was not a major factor in delaying conception, except in first parity cows. However, higher yielders were more likely to be inseminated, and less likely to be culled. Non-pregnant cows had a higher risk of being culled. Reproductive performance of dairy cows influenced a herd's profitability, and good heat detection and conception rates provided opportunities for management control. It was not always economically advantageous to get cows pregnant as soon as possible, and there was no one optimal value for the calving interval length for all cows in a herd.

Animals↗