Reproduction Research Papers - Academia.edu (original) (raw)

To test the hypothesis that selective breeding for high voluntary wheel running negatively affects maternal performance in house mice, we observed maternal behavior and compared litter size and mass, in replicate lines of selected (N =4) and control (N=4) mice from generations 20 and 21 of an artificial selection experiment. At generation 21, selected-line females ran 2.8-times more revolutions per day than females from random-bred control lines, when tested at approximately 6 weeks of age as part of the normal selection protocol. After giving birth, dams from selected and control lines exhibited similar frequencies of maternal behaviors and also spent similar amounts of time in general locomotor activity at litter ages of both 9 and 16 days. Dams from selected lines also performed equally well as controls in repeated pup-retrieval trials. At first parturition, selected-line dams averaged 2.4 g smaller in body mass as compared with dams from the control lines; however, neither litter size nor litter mass at birth (generation 20) or at weaning (generation 21) differed significantly between selected and control lines. We conclude that, at least under the husbandry conditions employed, maternal behavior and reproductive output at first parturition are genetically independent of wheel-running behavior.

- by
- •
- Genetics, Psychology, Cognitive Science, Reproduction

To increase the quality of cryopreserved sperm in white rhinoceros, the liquid nitrogen vapour (LN vapour) freezing and the multithermal gradient directional freezing methods were compared. Sixteen white rhinoceros (Ceratotherium simum sp.) were electroejaculated. Semen samples were diluted with cryoextender (Tris, lactose, egg-yolk, DMSO) and aliquoted into straws for LN vapour freezing, and glass hollow tubes for directional freezing. The sperm quality was evaluated before and after freezing by assessing the following parameters: motility, morphologic state, acrosomal integrity and plasma membrane function and integrity (i.e. sperm viability) as defined by the hypo-osmotic swelling. Directional freezing improved the sperm viability by 5.6% ( p < 0.005), progressive motility score by 34.7% and sperm motility index (SMI) by 8.1% ( p < 0.005) versus LN vapour freezing. When data was categorized into groups of low (<19%), moderate (20-39%) and high (>40%) percentages of morphologically normal, directional freezing (DF) resulted in 31.4% less abnormal acrosomes for the low quality group as well as 18.7% increase in intact acrosomes and 10.9% increase in motility for the high quality group compared to LN vapour freezing (LN) ( p < 0.01, p < 0.03, p < 0.01, respectively). LN showed a significant reduction in sperm head volume (5.7%, p < 0.05) compared to the prefreeze; whereas, no significant reduction in head volume was demonstrated after DF. Several additives (xanthenuric acid, cytochalasin D, potassium, EDTA) to the basic cryoextender provided no significant improvement in spermatozoal survival after directional freezing. In conclusion, directional freezing proved to facilitate higher gamete survival compared to LN vapour freezing. This is especially effective in ejaculates of low sperm quality and is important in endangered species where high quality semen donors are often not accessible. These results suggest that directional freezing could be valuable particularly for species with limited freezability of spermatozoa. #

- by Catherine Reid and +1
- •
- Reproduction, Cryopreservation, Endangered Species, Theriogenology

The objective of this study was to estimate the prevalence of and risk factors for pathological conditions of the reproductive organs in stray dogs under tropical conditions. Three hundred and eighteen dogs were examined post-mortem in the period from 1 July 2002 to 30 June 2003. Before killing, a blood sample (from the cephalic vein) for testosterone assay was taken. Pathological conditions of the reproductive organs were found in 135 of the dogs (42.5%) and in 175 of the testes (64.8%). The most frequent pathologies found were testicular degeneration, cryptorchidism, testicular hypoplasia and testicular tumours (in 15.1%, 6.6%, 6.6% and 5.4% of the dogs and 15.1, 4.6, 6.0 and 3.5 of the testes, respectively). Transmissible venereal tumour (TVT) was seen in 5.4% of the dogs. Testicular degeneration was more common in old dogs and underweight dogs (p < 0.05). Testicular tumours were 14.3 times more common in cryptorchid dogs. Age was another important factor for the development of testicular tumours (p < 0.05). Lower levels of testosterone concentration (p < 0.05) were observed in dogs with advanced testicular degeneration (0.7 +/- 0.8 nM), dogs with hypoplastic testicles (0.8 +/- 0.9 nM) and dogs with one degenerated and one retained testis or with bilateral cryptorchidism (1.2 +/- 0.9 nM) compared to dogs with one or two normal testes (7.0 +/- 5.5 nM). Testicular volume and weight were significantly lower in degenerated, hypoplastic and retained testes compared with the contralateral normal testis. Some spermatogenic activity was found in three of the retained testes, producing oligozoospermic smears with a high percentage of sperm abnormalities. No comparable epidemiological data about male pathological conditions of the reproductive organs in the dog is available. The prevalence found in this study, yet, appears high.

- by Antonio Ortega-pacheco and +2
- •
- Reproduction, Mexico, Biological Sciences, Dogs

The golden cownose ray, Rhinoptera steindachneri, was one of the most abundant species landed in artisanal elasmobranch fisheries in the northern Gulf of California (Baja California and Sonora) and Bahía Almejas, Mexico during 1998-1999. In the northern Gulf of California, R. steindachneri was most frequently observed during summer months (11.4% of elasmobranch landings, catch per unit effort (CPUE) = 6.8 individuals/vessel trip) and was rare during winter (0.1%, CPUE = 0.1). In Bahía Almejas, its relative abundance was greater during August (5.2%) than June (0.3%), a trend also evident in CPUE (August = 1.2, June = 0.1). The mean size of R. steindachneri landed in the Gulf of California was 64.3 ± 12.8 (SD) cm disc width (DW). Median size at maturity for Gulf of California specimens was similar for females (70.2 cm DW) and males (69.9 cm DW). Fecundity was found to be one offspring per female, with parturition estimated to occur from late June-August. Size at birth was estimated at 38-45 cm DW after a gestation period of approximately 11-12 months. Greater maximum sizes (to 104 cm DW) and embryo sizes (to 43 cm DW) were observed in Bahía Almejas. The large size at maturity, low fecundity, and long gestation period determined for R. steindachneri indicate that this species could be particularly susceptible to overexploitation.

- by Joseph Bizzarro
- •
- Reproduction, Fisheries, Biology, Ecology

The agouti (Dasyprocta leporina) and paca (Agouti paca) are among the largest extant rodent species. Although these species have considerable economic potential, there are few reports in the literature concerning male reproductive biology in sexually mature agoutis and pacas. The objectives of the present study were to perform detailed stereologic and histologic analyses of the testis and estimate spermatogenic cycle length in these 2 Neotropical rodent species as well as to compare the data with those from other well-studied rodent members of the Hystricomorpha and Myomorpha suborders. Eight adult agoutis and 6 adult pacas were used. The spermatogenic cycle in agoutis and pacas lasted 9.5 6 0.03 and 11.5 6 0.16 days, respectively, whereas the total duration of spermatogenesis for these 2 species was 42.8 6 0.16 and 51.6 6 0.7 days, respectively. Most of the parameters investigated were similar to those obtained for the other members of the Hystricomorpha suborder. As a result of the combination of high values of seminiferous tubule volume density, number of Sertoli cells per gram of testis, Sertoli cell efficiency, and a relatively short duration of spermatogenesis, the spermatogenic efficiency found in agoutis (52 6 2 6 10 6 ) and pacas (39 6 2 6 10 6 ) was particularly high when compared with that of previously investigated mammalian species. The data presented in this investigation would be useful for studies related to animal production as well as improvement and conservation programs involving these 2 large Neotropical rodent species.

- by Marcelo de Castro Leal
- •
- Reproduction, Rodentia, Spermatogenesis, tESTIS

First published in 1988, this volume redefined the anthropological study of menstrual customs. Examining cultures as diverse as long-house dwellers in North Borneo, African farmers, Welsh housewives, and postindustrial American workers, it challenged the previously widespread image of a universal "menstrual taboo" as well as the common assumption of universal female subordination that underlay it. Offering feminist perspectives on comparative gender politics and symbolism, the book has interested students and scholars in anthropology, women's studies, religion, and comparative health systems. Originally listed as a “Notable” book in Choice, it later won the first Most Enduring Edited Collection Prize, awarded by the Council for the Anthropology of Reproduction (a unit of the American Anthropological Association.). The book continues to be taught regularly around the world.

- by Alma Gottlieb
- •
- Gender Studies, Sex and Gender, Women's Studies, Feminist Theory

Pollen immigration can offset the effects of genetic drift and inbreeding in small populations. To understand the genetic consequences of forest fragmentation, estimates of pollen flow into remnant fragments are essential. Such estimates are straightforward for plants with singly sired, multiseeded fruits, since the pollen donor genotype for each fruit can be unambiguously reconstructed through full-sib genealogical analyses. Allozyme analyses were used to estimate pollen donor numbers from the progeny of fruits of the tropical dry forest tree Enterolobium cyclocarpum in a small (9.8 ha) fragmented population (N = 11) over three reproductive seasons (1994, 1995, and 1996). These analyses indicate that each tree receives pollen from many pollen donors. When data are pooled for the site, estimated maximum pollen donor pool sizes in all years exceed the number of individuals (56) in the 227 ha study area. Although unidentified pollen donors may be located as close as 250 m to the study...

- by John Nason
- •
- Genetics, Genetic Drift, Reproduction, Costa Rica

Policy debates have focused on who can participate in or access single-sex activities or services. This article describes how science of the biology of sex is relevant to three major policy areas: parenting (including leaves), sports, and public spaces. We focus on what scientists know about sex and gender (and gender/sex, where gender and sex are intertwined), and the role of various biological factors, including hormones such as testosterone and estradiol as well as genetics, gonads, genitals, and more. The policies under debate often use “biological sex,” but this fails to account for scientific understandings of sex and gender, misrepresents sex as single-faceted and binary, and overlooks scientific consensus about the importance of gender and identity.

- by Sari van Anders and +4
- •
- Sex and Gender, Sexual and Reproductive Health, Transgender Studies, Reproduction

Catalina de Erauso was a Spanish nun—turned soldier—who lived in 17th century Spain. Dressed as a man for almost two decades, she travelled to the Colonies to test her luck in the army, where she made the grade of ensign. In 1624 she wrote her memoirs. Unfortunately, the original manuscript was lost and the text which has survived is a copy, probably penned by an amanuensis. In 1996, an English translation of her memoirs was published. In my paper I will argue that the translation of the Stepto’s translation reflects a cultural bias and shows little effort at researching the nun's deeds and words. I will also examine gender attitudes in the Renaissance, and later periods, and the role of the Church in curtailing women from attaining intellectual maturity. To back my claims, I use Catalina's original text and contrast it with subsequent editions. I hope to prove that the English translation veers more towards sensationalism than to a deep and abiding respect for the nun’s misfortunes.
Keywords: Gender; translating issues; transvestite; Basque; anachronisms

- by Maria Odette Canivell
- •
- Spanish Literature, Gender Studies, Sex and Gender, Translation Studies
- by david haukos and +2
- •
- Climate Change, Reproduction, Biology, Medicine

Sperm donation seems to be the only solution in cases of negative results with testicular sperm extraction (TESE). However, it implies a genetic dissociation between husband and offspring that results in psychological stress, as well as ethical and existential dilemmas for the couple. Facing these dilemmas, some couples prefer father-to-son donation as an alternative solution. However, father-to-son sperm donation involves many potential medical, ethical and emotional risks. A broad discussion within the scienti®c community on these issues should contribute towards a better approach of these cases.

- by N. nikolettos Nikolettos
- •
- Ethics, Reproduction, Family, Medical Ethics

Atrazine, a chlorotriazine herbicide, is used to control annual grasses and broadleaf weeds. In this review, we summarize our laboratory's work evaluating the neuroendocrine toxicity of atrazine (and related chlorotriazines) from an historic perspective. We provide the rationale for our work as we have endeavored to determine: 1) the underlying reproductive changes leading to the development of mammary gland tumors in the atrazine-exposed female rat; 2) the cascade of physiological events that are responsible for these changes (i.e., the mode of action for mammary tumors); 3) the potential cellular mechanisms involving adverse effects of atrazine; and 4) the range of reproductive alterations associated with this pesticide.

- by Michael G Narotsky
- •
- Reproduction, Aging, Biology, Pregnancy

Objecti®e: The purpose of this study was to evaluate the efficacy and safety of intravaginal misoprostol for labor induction. Methods: 110 singleton term pregnancies with or without rupture of membranes were enrolled. Fraction-Ž. ated doses of misoprostol were applied 50᎐100 g , every 6 h until a maximum of three doses or beginning of labor. Ž. Results: The average interval "S.D. from vaginal application to the beginning of active labor and to delivery were, Ž. respectively, 9.5" 5.7 h and 14.8" 9.5 h. Failed labor induction was observed in two cases 2%. Cesarean section rate was 14%. The incidence of tachysystole was 18% and hypersystole 4%, but these situations were associated with Ž. abnormal fetal heart rate pattern hyperstimulation in only 3%. No maternal side effects and neonatal adverse effects were noted. Conclusions: Intravaginal misoprostol administration with low doses is an effective and safe method for labor induction in term pregnancies, with or without rupture of membranes.

- by DOUGLAS TIAGO
- •
- Physiology, Research Methodology, Reproduction, Biology

Approximately 3% of infants born have at least one serious congenital malformation. In the U.S., an average of 10 infants per thousand die before 1 y of life; about half of these deaths can be attributed to birth defects, low birth weight or prematurity. Although the causes of developmental abnormalities are clearly multifactorial in nature, we suggest that a common factor contributing to the occurrence of developmental abnormalities is suboptimal mineral nutrition during embryonic and fetal development. Using zinc and copper as examples, evidence is presented that nutritional deficiencies can rapidly affect the developing conceptus and result in gross structural abnormalities. Deficits of zinc or copper can result in rapid changes in cellular redox balance, tissue oxidative stress, inappropriate patterns of cell death, alterations in the migration of neural crest cells and changes in the expression of key patterning genes. In addition to well-recognized malformations, mineral deficiencies during perinatal development can result in behavioral, immunological and biochemical abnormalities that persist into adulthood. Although these persistent defects can in part be attributed to subtle morphological abnormalities, in other cases they may be secondary to epigenetic or developmental changes in DNA methylation patterns. Epigenetic defects combined with subtle morphological abnormalities can influence an individual's risk for certain chronic diseases and thus influence his or her risk for morbidity and mortality later in life.

- by Robert Rucker
- •
- Nutrition and Dietetics, Nutrition, Reproduction, Aging

Cryopreserved spermatozoa are prone to cryoinjury which induces membrane damage and render them incapable to undergo acrosome reaction (AR). In the present study, cryopreserved semen samples obtained from 30 Karan Fries bulls were subjected to in vitro AR. The AR scores were correlated with the fertility rates (conception rates) following A.I. with frozen semen frozen semen. The AR scores and gross seminal parameters showed significant correlations except for semen volume. A prediction equation (R 2 = 37.3) was constructed from AR scores and was used to predict the conception rates of donor bulls. The predicted and observed conception rates did not show any significant difference for chi square test. The study indicates that in vitro acrosome reaction test may be complemented with the conventional semen analyses tests prior to using cryopreserved semen samples for AI purpose.

- by Archana Verma
- •
- Reproduction, Indian

and aggression during the breeding season. However, the role of T in year-round territorial birds is still enigmatic, especially in tropical birds. Spotted antbirds (Hylophylax n. naevioides) defend territories in the Panamanian rainforest year-round but have low plasma T levels (0.1-0.2 ng/ml), except during brief periods of social challenges. We manipulated T action in captive male Spotted antbirds to test whether this hormone is involved in the regulation of song and aggression. Timplants increased plasma androgen levels (T and dihydrotestosterone) and enhanced song in nonbreeding males. During a staged male-male encounter, T-implanted males sang more and were more aggressive than controls. In a second experiment, we blocked the two known T actions: its binding to androgen receptors and its conversion into estradiol by the enzyme aromatase. For this, we administered the androgen receptor antagonist flutamide (Flut) in combination with the aromatase inhibitor 1-4-6 androstatrien-3,17-dione (ATD) to birds in breeding condition. ATD ؉ Flut treatment significantly elevated plasma levels of luteinizing hormone, presumably via the lack of T feedback from its receptors. ATD ؉ Flut-treated birds gave fewer spontaneous songs than control-implanted males. During staged male-male encounters, ATD ؉ Flut-treated males did not sing at all and showed reduced aggressive behavior. Our data indicate that T can regulate aggressive behavior in these tropical birds. Although plasma T levels can be low year-round, Spotted antbirds may use T either by secreting it briefly during social challenges, by having a high sensitivity to T action, or by enzymatically converting circulating T precursors directly at the site of action. We hypothesize that plasma T levels are kept low in these year-round territorial birds to avoid potentially detrimental effects of tonically elevated T. Future treatment of nonbreeding birds with ATD ؉ Flut will reveal whether T is indeed involved year-round in regulating aggressive behavior.

- by Kiran Soma
- •
- Physiology, Zoology, Animal Behavior, Reproduction

The aim of this study was to assess Australian girls' beliefs and feelings about menarche and menstruation using both quantitative and qualitative methodologies. Eighty-seven Grade 6 girls were interviewed and completed questionnaires, including both self-report and projective measures, relating to pubertal status, attitudes to and knowledge about menstruation. Results showed knowledge to be limited, with evidence of incorrect and negative myths about menstruation. Attitudes to menstruation were characterized by embarrassment, discomfort, and ambivalence about growing up. Themes in story completion tasks further reflected these attitudes, along with shame and anxiety, linked periods with incapacity or illness, and expressed the norm of periods as events which require the use of deception and denial as coping strategies. Mature problem-solving approaches to the hypothetical situations in the stories were rare. Factor analysis of the attitudinal and knowledge data revealed four factors — Comfort through Knowledge; Negative Feelings: Discomfort through Knowledge; and Independence — which were discussed in terms of the ambivalent social construction placed on menstruation.

- by Susan Moore
- •
- Psychology, Research Methodology, Coping Strategies, Qualitative methodology

Many animal species have complex cognitive abilities previously assumed to be limited to humans. Explanations for how these abilities evolved have focused on ways in which cognitive performance may influence survival, such as solving ecological problems or navigating complex social environments. However, sexual selection (differences in the reproductive success of individuals) can also lead to the evolution of complex traits. This could occur, for example, if females prefer males with better cognitive ability. A common assumption of models of female choice for male cognitive ability is that performance scores on different cognitive tasks are intercorrelated. In the present study, we evaluated performance of male satin bowerbirds on six cognitive tasks. Although we found little intercorrelation amongst males' performance scores of these tasks, males with better scores for two integrative measures of these cognitive tasks had higher mating success, which is a good indicator of reproductive success in this species. In addition, a multiple regression analysis suggested that performance on most cognitive tasks independently predicted mating success. Our results point to an important link between sexual selection and cognitive ability that has not been well appreciated and appears to be quite complex. Ó

- by Gerald Borgia
- •
- Cognition, Reproduction, Sexual Selection, Animal Behaviour

A matter of current, intense debate with regard to the effects of metals on biological systems is the potential toxicity of metals associated with food particles. Recently developed biotic ligand models (BLM), which predict the toxicity of waterborne metals, may not be valid if the dietary exposure route contributes to metal toxicity. The present study is, to our knowledge, the first that investigates the potential toxicity of dietary copper to a freshwater invertebrate (i.e., Daphnia magna) feeding on a live diet (i.e., the green alga Pseudokircheneriella subcapitata). Algae were exposed for 3 d to different copper concentrations, resulting in algal copper burdens between approximately 6.2 ϫ 10 Ϫ16 and 250 ϫ 10 Ϫ16 g cell Ϫ1. These algae were then used as food in chronic, 21-d D. magna toxicity tests in which growth, reproduction, and copper accumulation were assessed. Three exposure scenarios were tested: A waterborne exposure, a dietary exposure, and a combined waterborne and dietary exposure. Although exposure to dietary copper resulted in an increased copper body burden of the adult daphnids, it did not contribute to toxicity and did not affect the 21-d effect concentrations expressed as waterborne copper, indicating that the previously established good predictive capacity of the chronic D. magna BLM is not affected. On the contrary, exposure to the highest dietary copper levels resulted in an increase of as much as 75% in growth and reproduction. To our knowledge, this is the first evidence that dietary copper exposure of a freshwater invertebrate feeding on a live diet resulted in a beneficial effect.

- by colin Janssen
- •
- Ecotoxicology, Reproduction, Crustacea, Biology

As studies uncover the breadth of microbes associated with human life, opportunities will emerge to manipulate and augment their functions in ways that improve health and longevity. From involvement in the complexities of reproduction and fetal/infant development, to delaying the onset of disease, and indeed countering many maladies, microbes offer hope for human well-being. Evidence is emerging to suggest that microbes may play a beneficial role in body sites traditionally viewed as being sterile. Although further evidence is required, we propose that much of medical dogma is about to change significantly through recognition and understanding of these hitherto unrecognized microbe-host interactions. A meeting of the International Scientific Association for Probiotics and Prebiotics held in Aberdeen, Scotland (June 2014), presented new views and challenged established concepts on the role of microbes in reproduction and health of the mother and infant. This article summarizes some o...

- by Juliet Ansell
- •
- Immunology, Probiotics, Reproduction, Prebiotics
- by Martine Migaud
- •
- Neuroscience, Cognitive Science, Reproduction, RNA interference

Carotenoid-dependent plumage displays are widely assumed to be honest indicators of individual health or quality, which are used as cues during mate choice and/or agonistic signalling. Despite the fact that red, yellow and orange pigmentation of bills is common, and also variable between individuals, comparatively little is known about bill colouration as a condition-dependent trait. Furthermore, many studies of avian colouration are confounded by the lack of objective colour quantification and the use of overly simplistic univariate techniques for analysis of the relationship between the condition-dependent trait and individual quality variables. In this study, we correlated male blackbird bill colour (a likely carotenoid-dependent sexually selected trait) with body/condition variables that reflect male quality. We measured bill colour using photometric techniques, thus ensuring objectivity. The data were analysed using the multivariate statistical techniques of canonical ordination. Analyses based on reflectance spectra of male blackbird bill samples and colour components (i.e. hue, chroma and brightness) derived from the reflectance spectra were very similar. Analysing the entire reflectance spectra of blackbird bill samples with Redundancy Analysis (RDA) allowed examination of individual wavelengths and their specific associations with the body/condition variables. However, hue, chroma and brightness values also provided useful information to explain colour variation, and the two approaches may be complimentary. We did not find any significant associations between male blackbird bill colour and percent incidence of ectoparasites or cloaca size. However, both the colour component and full spectral analyses showed that culmen length explained a significant amount of variation in male blackbird bill colour. Culmen length was positively associated with greater reflectance from the bill samples at longer wavelengths and a higher hue value (i.e. more orange-pigmented bills). Larger males may have larger territories or be better at defending territories during male-male interactions, ensuring access to carotenoid food sources. Future studies should elucidate the relationship between bill colour and behavioural measures such as aggressiveness, territory size, song rate and nest attendance.

- by Carolyn King
- •
- Psychology, Cognitive Science, Multivariate Statistics, Pigmentation

Abstract: Although there are many indicators of endangerment (i.e., whether populations or species meet criteria that justify conservation action), their reliability has rarely been tested. Such indicators may fail to identify that a population or species meets criteria for conservation action (false negative) or may incorrectly show that such criteria have been met (false positive). To quantify the rate of both types of error for 20 commonly used indicators of declining abundance (threat indicators), we used receiver operating characteristic curves derived from historical (1938–2007) data for 18 sockeye salmon (Oncorhynchus nerka) populations in the Fraser River, British Columbia, Canada. We retrospectively determined each population's yearly status (reflected by change in abundance over time) on the basis of each indicator. We then compared that population's status in a given year with the status in subsequent years (determined by the magnitude of decline in abundance across those years). For each sockeye population, we calculated how often each indicator of past status matched subsequent status. No single threat indicator provided error-free estimates of status, but indicators that reflected the extent (i.e., magnitude) of past decline in abundance (through comparison of current abundance with some historical baseline abundance) tended to better reflect status in subsequent years than the rate of decline over the previous 3 generations (a widely used indicator). We recommend that when possible, the reliability of various threat indicators be evaluated with empirical analyses before such indicators are used to determine the need for conservation action. These indicators should include estimates from the entire data set to take into account a historical baseline.Resumen: Aunque existen muchos indicadores de riesgo (i.e., sí las poblaciones o especies cumplen con criterios para justificar acciones de conservación), su confiabilidad ha sido probada pocas veces. Dichos indicadores pueden fallar al identificar que una población o especie cumple con criterios para acciones de conservación (negativo falso) o pueden mostrar incorrectamente que tales criterios se han cumplido (positivo falso). Para cuantificar la tasa de ambos tipos de error para 20 indicadores de declinación de abundancia (indicadores de amenaza) utilizados comúnmente, utilizamos curvas de características de operación de receptores derivadas de datos históricos (1937–2008) de 18 poblaciones de salmón (Oncorhynchus nerka) en el Río Fraser, Columbia Británica, Canadá. Retrospectivamente determinamos el estatus anual de cada población (reflejado en cambios en la abundancia en el tiempo) con base en cada indicador. Posteriormente comparamos el estatus de la población en un año determinado con el estatus de años subsecuentes (determinado por la magnitud de la declinación en abundancia en esos años). Para cada población de salmón, calculamos la frecuencia en que cada indicador de estatus pasado era igual al estatus subsecuente. Ningún indicador de amenaza proporcionó estimaciones de estatus libres de error, pero los indicadores que reflejaron la extensión (i.e., magnitud) de la declinación en abundancia pasada (mediante comparación de la abundancia actual con la abundancia histórica de referencia) tendieron a reflejar de mejor manera el estatus en años anteriores que la tasa de declinación en las 3 generaciones previas (un indicador ampliamente utilizado). Recomendamos que, cuando sea posible, se evalúe la confiabilidad de varios indicadores de amenaza con análisis empíricos antes de que esos indicadores sean utilizados para determinar la necesidad de acciones de conservación. Estos indicadores deben incluir estimaciones a partir del total de datos para considerar una referencia histórica.Resumen: Aunque existen muchos indicadores de riesgo (i.e., sí las poblaciones o especies cumplen con criterios para justificar acciones de conservación), su confiabilidad ha sido probada pocas veces. Dichos indicadores pueden fallar al identificar que una población o especie cumple con criterios para acciones de conservación (negativo falso) o pueden mostrar incorrectamente que tales criterios se han cumplido (positivo falso). Para cuantificar la tasa de ambos tipos de error para 20 indicadores de declinación de abundancia (indicadores de amenaza) utilizados comúnmente, utilizamos curvas de características de operación de receptores derivadas de datos históricos (1937–2008) de 18 poblaciones de salmón (Oncorhynchus nerka) en el Río Fraser, Columbia Británica, Canadá. Retrospectivamente determinamos el estatus anual de cada población (reflejado en cambios en la abundancia en el tiempo) con base en cada indicador. Posteriormente comparamos el estatus de la población en un año determinado con el estatus de años subsecuentes (determinado por la magnitud de la declinación en abundancia en esos años). Para cada población de salmón, calculamos la frecuencia en que cada indicador de estatus pasado era igual al estatus subsecuente. Ningún indicador de amenaza proporcionó estimaciones de estatus libres de error, pero los indicadores que reflejaron la extensión (i.e., magnitud) de la declinación en abundancia pasada (mediante comparación de la abundancia actual con la abundancia histórica de referencia) tendieron a reflejar de mejor manera el estatus en años anteriores que la tasa de declinación en las 3 generaciones previas (un indicador ampliamente utilizado). Recomendamos que, cuando sea posible, se evalúe la confiabilidad de varios indicadores de amenaza con análisis empíricos antes de que esos indicadores sean utilizados para determinar la necesidad de acciones de conservación. Estos indicadores deben incluir estimaciones a partir del total de datos para considerar una referencia histórica.

- by Nick Dulvy
- •
- Conservation Biology, Reproduction, Biological Sciences, Environmental Sciences

Central to the ecology and evolution of a broad range of plants is understanding why they routinely have submaximal reproduction manifested as low seed : ovule and fruit : flower ratios. We know much less about the processes responsible for low seed : ovule ratios than we do for fruit : flower ratios. Current hypotheses for low seed : ovule ratios are largely drawn from those for fruit : flower ratios, including proximate (ecological) causes of pollen limitation, resource limitation, and pollen quality, as well as the ultimate (evolutionary) hypothesis of ''bet hedging'' on stochastic pollination. Yet, such mechanisms operating on fruit : flower ratios at the whole-plant level may not best explain low seed : ovule ratios at the individual-flower level. We tested each of these proximate and ultimate causes for low seed : ovule ratios using the specialized pollination mutualism between senita cacti (Pachycereus schottii) and senita moths (Upiga virescens). Seed : ovule ratios were consistently low (;0.61). Such excess ovule production by senita likely has a strong genetic component given the significant differences among plants in ovule number and the consistency in ovule production by plants within and among flowering seasons. Excess ovule production and low seed : ovule ratios could not be explained by pollen limitation, resource limitation, pollen quality, or bet hedging. Nevertheless, phenotypic selection analyses did show significant selection gradients for increased ovule number, suggesting that other evolutionary processes may be responsible for excess ovule production and low seed : ovule ratios. In contrast, low fruit : flower ratios at the whole-plant level were explained by an apparent equilibrium between pollen and resource limitation. Thus, mechanisms responsible for low fruit : flower ratios at the whole-plant level are not necessarily in accord with those of low seed : ovule ratios at the individual-flower level. This suggests that we may need to adopt a more pluralistic approach to seed : ovule ratios and consider alternative hypotheses, including a greater array of proximate and ultimate causes. Initial results of this study suggest that floral allometry, selection on correlated floral traits, stigma clogging with pollen grains, and style clogging with pollen tubes may provide promising avenues for understanding low seed : ovule ratios.

- by Nathaniel Holland
- •
- Genetics, Reproduction, Ecology, Phenotypic selection

The use of archival depth telemetry as a means of remotely assessing the reproductive rates of freeranging fishes is explored. This is achieved by electronically tracking the vertical movements of individual female small spotted catsharks Scyliorhinus canicula in the natural environment, whilst simultaneously evaluating the temporal and vertical distributions of egg-laying in this species. Distinctive patterns of short-term (0·3-3·7 h), shallow-water activity are documented in the time-depth profiles of female S. canicula that occur at an appropriate depth (1·0-2·3 m) and periodicity (every 10-12 days) to represent egg-laying behaviour. Putative egg-laying behaviour was exhibited simultaneously by two individually tracked female S. canicula during late-spring and early-summer. The results highlight that, provided species behaviour is suitable and complementary methods such as previous data, laboratory experiments and field surveys can be used to validate the patterns observed, archival depth telemetry offers an unobtrusive means by which egg production and egglaying behaviour of free-living fishes can be estimated. As precise information regarding life-history parameters is difficult to obtain for free-ranging fish species, this technique could be used to improve the parameterization of species demographic models that are relevant to the management of wild fish populations.

- by David Sims
- •
- Zoology, Reproduction, Ecology, Population Dynamics

The testis is a tightly controlled dynamic tissue. In mammals, there is growing evidence that estrogen plays a role in the regulation of testicular functions. In teleosts, high levels of 17beta-estradiol (E 2 ) in serum correlate with the end of spermatogenesis, spawning, and the initiation of postspawning stages when spermatogonia are the main cell types in the testis. Moreover, E 2 modulates leukocyte functions in several teleost species. We hypothesized, therefore, that E 2 would induce the infiltration of acidophilic granulocytes and cause a resumption of testicular cell proliferation in spermatogenically active gilthead seabream males. Several studies of this species have reported that supraphysiological doses of E 2 are needed to induce histological and developmental changes in males. In fact, as gilthead seabream is a protandrous hermaphrodite teleost, long exposures (6-14 wk) to high doses of E 2 result in feminization of the males. Taking all this into account, we sharply increased E 2 levels during short times by i.p. injecting E 2 diluted in coconut oil as the vehicle and sampled the fish after 7, 13, and 18 days to assess the effects that E 2 had on spermatogenesis. It was observed that E 2 levels in plasma increased, while 11-ketotestosterone (11-KT) and testosterone (T) levels remained unaltered. However, 11-KT and T levels strongly increased in control fish 18 days postinjection. The most relevant result of our study was that E 2 accelerates the final events of spermatogenesis, inhibits the proliferation of spermatogonia in early stages, and induces some of the processes that usually occur during postspawning, such as the infiltration of acidophilic granulocytes and the apoptosis of primary spermatogonia. Strikingly, neither the shedding of spermatozoa nor an increase in the proliferative rate of spermatogonia stem cells was observed, probably because of the lack of other necessary stimuli, such as the increase in T levels that takes place during normal postspawning.

- by Elena Chaves-pozo and +2
- •
- Immunology, Reproduction, Apoptosis, Biological Sciences

This study was conducted to correlate body condition score (BCS) in mares with ultrasonic measurements of subcutaneous fat taken at four locations (tailhead, rump, 13th rib, and withers), and to determine which site might be the most reliable area of measurement. Twentyfour light horse mares were assigned to either a high BCS group (8.0-9.0) or a low BCS group (3.0-3.5). From September to December 1999, mares were full grazed or restricted to reach their respective target BCS; they were then maintained at that BCS until the following May. Ultrasonic fat measurements were recorded every 14 days from September to May. Over time, mares in the low BCS group lost subcutaneous fat and mares in the high BCS group deposited subcutaneous fat at all four locations (P < .02). In both the high and low BCS groups, subcutaneous fat at the rump changed much less over the course of the experiment than did the amount of subcutaneous fat at the tailhead, 13th rib, and withers. Correlation coefficients (r) between BCS and subcutaneous fat thickness were: 0.87, 0.84, 0.82, and 0.86 for the tailhead, rump, 13th rib, and withers, respectively. The tailhead area accounted for the majority of the variation in BCS (R 2 = 0.75). Overall, 78% of the variation could be accounted for when the 13th rib and withers were combined with the tailhead; however, the rump did not significantly contribute or account for variation. This study shows that body condition score and subcutaneous fat measurements are correlated, especially at the tailhead area. Application of the system developed by Henneke et al, 1 with particular emphasis on the amount of fat in areas such as the tailhead, 13th rib, and withers, can provide an accurate estimate of the condition and/or body fat content of a mare.

- by C. Sniffen and +1
- •
- Reproduction, Dairy Science, Lactation, Animal Production

Sexual behavior was observed in fifteen female and seven male captive adult chimpanzees over a period of three months. Relative frequencies of successful and unsuccessful copulatory attempts were compared to levels of anogenital swelling and reproductive status. In addition, the data were analyzed in relation to three indicators of female primate sexuality: 1) proceptivity, indicated by female attempts a t sexual interaction; 2) attractivity, indicated by male-initiated attempts; and 3 ) receptivity, evident when a female responds positively to male initiation. The data suggest that increased level of anogenital swelling enhanced female proceptivity and attractivity, but not receptivity. Comparison of cycling vs pregnant females revealed that attractivity and receptivity increased during pregnancy, while proceptivity was relatively unchanged. The total success rate (copulationsiattempts) was 63.3% (42% for female-initiated attempts and 77% for male-initiated attempts). Pregnant females copulated at a high rate, almost double that of cycling females. Sexual activity during pregnancy and the occurrence of anogenital swelling during pregnancy are discussed in terms of female reproductive strategies.

- by Janette Wallis
- •
- Zoology, Reproduction, Sexual Behavior, Pan troglodytes

Spring temperatures in temperate regions have increased over the past 20 years and many organisms have responded to this increase by advancing the timing of their growth and reproduction. However, not all populations show an advancement of phenology. Understanding why some populations advance and others do not will give us insight into the possible constraints and selection pressures on the advancement of phenology. By combining two decades of data on 24 populations of tits (Parus sp.) from six European countries, we show that the phenological response to large-scale changes in spring temperature varies across a species' range, even between populations situated close to each other. We show that this variation cannot be fully explained by variation in the temperature change during the pre-and post-laying periods, as recently suggested. Instead, we find evidence for a link between rising temperatures and the frequency of second broods, which results in complex shifts in the laying dates of first clutches. Our results emphasize the need to consider links between different life-history parameters in order to predict the ecological consequences of large-scale climate changes.

- by Jenny Laet and +2
- •
- Climate Change, Reproduction, Life history, Ecology

Since the 1960s, mink (Mustela vison) populations in Georgia, North Carolina, and South Carolina have declined, especially in the coastal plain. A prior study suggested that the decline may stem from environmental contaminants. Based on water quality data from each state, we identified 17 substances potentially related to the decline: aldrin, dieldrin, endrin, DDD, DDE, DDT, PCBs, chlordane, alpha-BHC, toxaphene, dibenzofuran, copper, chromium, cadmium, lead, arsenic, and mercury. Mink livers were analyzed for PCB and organochlorine pesticides, and kidneys and femurs were analyzed for metals. Reference sample concentrations from piedmont, mountain, and foothill locations were compared to state coastal plain totals and counties. PCBs for Georgia, dieldrin for South Carolina, and endrin and aldrin for North Carolina were significantly higher than the piedmont reference group. Liver PCB concentrations were higher than those known to cause mink reproductive dysfunction. Mercury concentrations were significantly higher in coastal plain mink from all three states and were in the range of those known to cause impacts to reproduction, growth, and behavior to wild mink. It is unknown what concentrations of cyclodienes cause reduced reproduction or other physiological effects in mink, but the levels reported here probably indicate background concentrations that do not contribute to the decline.

- by Larry Brewer
- •
- Water quality, Reproduction, Arsenic, Multidisciplinary

The trend of increasing cow numbers per husbandry person makes it difficult to achieve good reproductive management by traditional means. A system to predict the reproductive status of cows would be of great value. There exist time-series models for detecting oestrus from milk traits other than progesterone and decision strategies for interpreting progesterone measures have been suggested but a system combining these aspects to predict not just oestrus but reproductive status throughout the reproductive cycle is lacking. The objective of this study was to develop such a model on the basis of automated milk progesterone sampling.

- by Nicolas Friggens
- •
- Animal Behavior, Reproduction, Theriogenology, Biological Sciences

Polycystic ovarian syndrome (PCOS), the most common female endocrine disorder of unknown etiology, is characterized by reproductive abnormalities and associated metabolic conditions comprising insulin resistance, type 2 diabetes mellitus, and dyslipidemia. We previously reported that transgenic overexpression of nerve growth factor (NGF), a marker of sympathetic hyperactivity, directed to the ovary by the mouse 17␣-hydroxylase/C 17-20 lyase promoter (17NF mice), results in ovarian abnormalities similar to those seen in PCOS women. To investigate whether ovarian overproduction of NGF also induces common metabolic alterations of PCOS, we assessed glucose homeostasis by glucose tolerance test, plasma insulin levels, and body composition by dual-energy x-ray absorptiometry scan in young female 17NF mice and wild-type mice. 17NF mice exhibited increased body weight and alterations in body fat distribution with a greater accumulation of visceral fat compared with sc fat (P Ͻ .01). 17NF mice also displayed glucose intolerance (P Ͻ .01), decreased insulin-mediated glucose disposal (P Ͻ .01), and hyperinsulinemia (P Ͻ .05), which, similar to PCOS patients, occurred independently of body weight. Additionally, 17NF mice exhibited increased sympathetic outflow observed as increased interscapular brown adipose tissue temperature. This change was evident during the dark period (7 PM to 7 AM) and occurred concomitant with increased interscapular brown adipose tissue uncoupling protein 1 expression. These findings suggest that overexpression of NGF in the ovary may suffice to cause both reproductive and metabolic alterations characteristic of PCOS and support the hypothesis that sympathetic hyperactivity may contribute to the development and/or progression of PCOS. (Endocrinology 155: 4494 -4506, 2014) P olycystic ovarian syndrome (PCOS) is the most common endocrine disorder affecting women of reproductive age, with a worldwide prevalence of 6%-10% (1, 2). PCOS is also the most common cause of female infertility.

- by P. Enriori
- •
- Endocrinology, Reproduction, Biological Sciences, Mice

Parental (genomic) imprinting is the process by which the differential expression of maternal and paternal alleles at certain genetic loci in mammalian embryos occurs. Such loci are implicated in the control of fetal, placental and neonatal growth, and, more generally, in diverse aspects of fetal nutrient acquisition and maternal-fetal interactions. Not surprisingly, the aberrant expression of imprinted genes is implicated in a range of embryonic and fetal abnormalities. We outline how an evolutionary theory, based on classic parent-offspring conflict theory, relates to certain fetal growth abnormalities. In particular, we suggest that growth abnormalities resulting from the manipulation of preimplantation mammalian embryos in vitro (for example large calf syndrome) may reflect the occurrence of genetic conflict over the fetal growth programme in the early preimplantation period.

- by Wolf Reik
- •
- Genetics, Physiology, Reproduction, Genomic Imprinting

During 1997, quarterly exploratory cruises of the R/V``Archipelago'' were carried out in order to study the deep water crab Chaceon af®nis [Res. Camp. Sci. Mo Ânaco Fasc. VII (1894) 1], South of Pico island (Azores) and at the Menez Gwen hydrothermal vent area (SW of the Azores, within the Azorean Economic Exclusive Zone). The crabs were caught with bottom traps according to a speci®ed survey design. Different areas between 300 and 1200 m depth were surveyed. Information from previous collections was also compiled and analysed. A total of 1153 crabs (726 males and 427 females) were caught at depths ranging from 600 to 1100 m on rocky and/or muddy bottoms. Size ranged from 39 to 177 mm carapace length (CL), the males being larger than females. Males were relatively more abundant at depths <800 m and females relatively more abundant at depths >800 m. The greatest abundance occurred at depths from 700 to 800 m. Ovigerous females, which were consistently >70 mm CL, were found only from October to March. An annual reproductive cycle is suggested. Size at ®rst maturity for the females, was estimated to be within the size range of 83±97 mm CL. Other ecological and biological information such as distribution, morphometric aspects related to reproduction, occurrence of parasites and epibionts, are discussed, as well as by-catch species.

- by Luislis Morales Galindo
- •
- Reproduction, Fisheries, Crustacea, Biology

An invasive population of Burmese pythons (Python molurus bivittatus) is established across several thousand square kilometers of southern Florida and appears to have caused precipitous population declines among several species of native mammals. Why has this giant snake had such great success as an invasive species when many established reptiles have failed to spread? We scored the Burmese python for each of 15 literature-based attributes relative to predefined comparison groups from a diverse range of taxa and provide a review of the natural history and ecology of Burmese pythons relevant to each attribute. We focused on attributes linked to spread and magnitude of impacts rather than establishment success. Our results suggest that attributes related to body size and generalism appeared to be particularly applicable to the Burmese python's success in Florida. The attributes with the highest scores were: high reproductive potential, low vulnerability to predation, large adult body size, large offspring size and high dietary breadth. However, attributes of ectotherms in general and pythons in particular (including predatory mode, energetic efficiency and social interactions) might have also contributed to invasion success. Although establishment risk assessments are an important initial step in prevention of new establishments, evaluating species in terms of their potential for spreading widely and negatively impacting ecosystems might become part of the means by which resource managers prioritize control efforts in environments with large numbers of introduced species.

- by Gordon Rodda
- •
- Zoology, Reproduction, Biology, Diet
- by Paula Navarro
- •
- Surgery, Reproduction, Treatment, Health
- by Culum Brown
- •
- Evolutionary Biology, Zoology, Geography, Structure

The objective was to assess the magnitude causes and substandard care factors responsible for the third delay of maternal mortality seen in our unit III Department of Obstetrics and Gynecology Civil Hospital Karachi. This Cross-sectional retrospective study was carried out on 152 mothers who died over a period of eight years from 1997 to 2004 at Civil Hospital Karachi. Death summaries of all maternal deaths were reviewed from death registers and were studied for substandard care factors which could have been responsible for the third delay of maternal mortality. The frequency of maternal mortality was 1.3 per 100 deliveries. The mean age was 29+or-6.49 years and mean parity was 3.24+or-3.25. The main causes of death were hypertensive disorders in 52/152 (34.21%) hemorrhage in 40/152 (26.31%) unsafe abortion in 16/152 (10.52%) puerperal sepsis in 14/152 (9.21%) and obstructed labor in 11/152 (7.2%) cases. Substandard care factors were present in 76.7% of patients which included inapp...

- by Prof. Nusrat Shah
- •
- Research Methodology, Reproduction, Developing Countries, Population Dynamics

The frequency of hybridization in plants is context dependent and can be influenced by the local mating environment. We used progeny arrays and admixture and pollen dispersal analyses to assess the relative importance of pre-mating reproductive barriers and the local demographic environment as explanations of variation in hybrid frequency in three mapped hybrid zones of Eucalyptus aggregata and E. rubida. A total of 731 openpollinated progeny from 36 E. aggregata maternal parents were genotyped using six microsatellite markers. Admixture analysis identified substantial variation in hybrid frequency among progeny arrays (0-76.9%). In one hybrid zone, hybrid frequency was related to pre-mating barriers (degree of flowering synchrony) and demographic components of the local mating environment (decreasing population size, closer proximity to E. rubida and hybrid trees). At this site, average pollen dispersal distance was less and almost half (46%) of the hybrid progeny were sired by local E. rubida and hybrid trees. In contrast, at the other two sites, pre-mating and demographic factors were not related to hybrid frequency. Compared to the first hybrid zone where most of the E. rubida (76%) and all hybrids flowered, in the remaining sites fewer E. rubida (22-41%) and hybrid trees (0-50%) flowered and their reproductive success was lower (sired 0-23% of hybrids). As a result, most hybrids were sired by external E. rubida ⁄ hybrids located at least 2-3 km away. These results indicate that although pre-mating barriers and local demography can influence patterns of hybridization, their importance can depend upon the scale of pollen dispersal.

- by David Ayre
- •
- Geography, Reproduction, Seed Dispersal, Hybridization

Acrosomal loss was induced in marsupial spermatozoa by an intermediate of the phosphoinositide pathway. The diacylglycerol, 1,2-dioctanoyl-sn-glycerol (DiC8; 100 \g=m\moll \ m=-\ 1) induced acrosomal loss in 70% of brushtail possum (Trichosurus vulpecula) spermatozoa and in 80% of tammar wallaby (Macropus eugenii) spermatozoa. The DiC8-induced acrosomal loss was not enhanced by co-incubation with calcium ionophore A23187 and occurred in Ca2+free medium and in the presence of the calcium chelator EGTA (3 mmol l \m=-\1). There was no evidence of uptake of 45Ca2+ during the DiC8-induced acrosomal loss. Inhibitors of protein kinase C [1-(5-isoquinolinyl-sulfonyl)-2-methylpiperazine] and phospholipase A2 dexamethasone] did not effect DiC8-induced acrosomal loss in wallaby spermatozoa. The phorbol ester, phorbol 12-myristate 13-acetate, at a concentration of 10 \g=m\mol l \m=-\1had no effect on possum spermatozoa and induced acrosomal loss in only 6% of wallaby spermatozoa. It appears that the DiC8-induced acrosome reaction is not mediated by activation of the phosphoinositide pathway and that extracellular calcium is not required for the membrane fusion event. As acrosomal loss was seen only at relatively high concentrations of diacylglycerol (> 50 \g=m\moll \ m=-\ 1) and there is no evidence of involvement of other phosphoinositide intermediates or analogues, it is likely that its role is as a direct membrane fusogen.

- by John Rodger
- •
- Physiology, Reproduction, Calcium, Dexamethasone
- by Cesar Koppe Grisolia
- •
- Ecotoxicology, Reproduction, Multidisciplinary, Toxicity

The effects of four reagents on the activation and subsequent fertilization of equine oocytes, and the development of these after intracytoplasmic sperm injection, were investigated. Cumulus-oocyte complexes collected from equine ovaries obtained from an abattoir were matured in vitro for 40-44 h in TCM199 medium before being injected, when in metaphase II, with an immobilized stallion spermatozoon. The cumulus− oocyte complexes were then subjected to one of five activation treatments: (a) 10 µmol ionomycin l −1 for 10 min; (b) 7% (v/v) ethanol for 10 min; (c) 100 µmol thimerosal l −1 for 10 min; (d) 250 µmol inositol 1,4,5-triphosphate l −1 injection; and (e) no treatment (control). After 18-20 h further culture, the cumulus−oocyte complexes were assessed for activation by observing whether they had progressed through second anaphasetelophase and had formed a female pronucleus. The proportions of oocytes activated after each treatment were: 16/27 (59%) for ionomycin; 14/25 (56%) for ethanol; 22/28 (79%) for thimerosal; 15/27 (56%) for inositol 1,4,5-triphosphate; and 0/20 (0%) for the untreated controls. Thus, significantly more oocytes (P < 0.05) were activated by treatment with thimerosal than by the other four treatments. The proportions of oocytes that cleaved to the two-cell stage at 24-30 h after sperm injection in the groups treated with ionomycin, ethanol and thimerosal were 7/20 (35%), 5/19 (26%) and 11/23 (48%), respectively. No cleavage was observed in any of the control oocytes or those treated with inositol 1,4,5-triphosphate. Furthermore, evidence of normal fertilization was observed in 2/7 (29%), 2/5 (40%) and 7/11 (64%) of the oocytes treated with ionomycin, ethanol and thimerosal, respectively. These results demonstrated that: (a) it is possible to activate equine oocytes with the chemical stimulants, ionomycin, ethanol, thimerosal and inositol 1,4,5-triphosphate; (b) thimerosal is more effective than the other three reagents in facilitating both meiotic activation and normal fertilization of equine oocytes; and (c) chemical activation may also stimulate parthenogenetic cleavage of oocytes without concurrent changes in the head of the spermatozoon.

- by Lee Morris
- •
- Physiology, Reproduction, Reproduction and human fertility, Ethanol

The aim of this study was to evaluate the effect of progesterone supplementation and stage of oestrous cycle on in vitro maturation (IVM) of canine oocytes. Oocytes were cultured in medium supplemented with 0, 2000, 4000 or 8000 ng progesterone ml(-1) (Expt 1; n=274 oocytes) or 0, 20, 200 or 2000 ng progesterone ml(-1) (Expt 2; n=789 oocytes). In Expt 3, oocytes (n=1202) were cultured in a bi-phasic system of meiotic arrest followed by IVM, both in the presence of 0, 20, 200 or 2000 ng progesterone ml(-1). Rates of meiotic resumption for Expt 1 ranged from 40.0% to 58.5%; there were no significant differences among groups. In Expt 2, rate of meiotic resumption was significantly lower in the 2000 ng progesterone ml(-1) treatment (35.5%) compared with the 200 ng progesterone ml(-1) treatment (54.0%; P<0.05). There were no significant differences in rates of maturation to metaphase II among treatments in Expt 1 (1.8-8.6%) or Expt 2 (8.4-14.7%); however, oocytes collected from ovarie...

- by Duane Kraemer
- •
- Physiology, Reproduction, Oogenesis, Dogs

Biological Flora of the British Isles: Cirsium dissectum (L.) Hill ( Cirsium tuberosum (L.) All. subsp. anglicum (Lam.) Bonnier; Cnicus pratensis (Huds.) Willd., non Lam.; Cirsium anglicum (Lam.) DC.) Summary 1

- by Natasha De Vere
- •
- Conservation, Reproduction, Biology, Ecology
- by Saharnaz Nedjat
- •
- Criminology, Psychology, Domestic Violence, Research Methodology

The Mediterranean flour moth, Ephestia Kuehniella Zeller (Lepidoptera: Pyralidae), is an important pest in stored products worldwide, and is one of the major pests in flour mills in Algeria. Because environmental consideration, alternative approaches to neurotoxic insecticides, as well as safe, effective, and sound integrated pest management strategies are developed pest control agents such as the insect growth regulator (IGRs). Among these IGRs, the bisacylhydrazine derivatives are nonsteroidal ecdysterold agonists that mimic the action of moulting hormones and induce a precocious and incomplete moult in several insect orders. In topical bioassays using the pupae of E. kuehniella, three ecdysteroid agonists: RH-5849, the first bisaclhydrazine ecdysone agonist and two analogs, RH-5992 (tebufenozide) and RH-0345 (halofenozide), were evaluated on the reproduction under laboratory conditions. In a first series of experiments, the efficacy of these compounds was tested. These compounds ...

- by N. Soltani-Mazouni
- •
- Reproduction, Safety, Insecticides, Larva

The purpose of this study was to investigate the association between seropositivity for the most frequent Leptospira serovars and reproductive losses in sows in Brazil. Serum samples from 351 sows from 18 herds (in the state of Rio de Janeiro, Brazil) with low reproductive efficiency were tested (microscopic agglutination) for antibodies against serovars of Leptospira. Antibodies were detected in serum samples of 66.1% of all sows, most frequently serovar icterohaemorrhagiae (43.1%), followed by pomona (18.1%) and tarassovi (9.9%). Seroreactivity to icterohaemorrhagiae and pomona were associated (P < 0.05) with impaired reproductive performance (and substantial economic loss). Seroreactivity for pomona was associated (P < 0.05) with stillborn piglets and mummified fetuses, whereas seroreactivity to icterohaemorrhagiae was associated (P < 0.05) with the number of piglets born dead. #

- by Guilherme Souza
- •
- Reproduction, Brazil, Theriogenology, Biological Sciences