Reproductive aspects of the mosquito Culex quinquefasciatus (Diptera:Culicidae) infected with Wuchereria bancrofti (Spirurida: Onchocercidae)

This study reports on the relationship between Wuchereria bancrofti infection and female body size, intake of blood and fecundity in the mosquito Culex quinquefasciatus, vector of this filarial parasite in Recife (Brazil). Adults from field collected larvae were infected via a membrane feeding procedure, using blood with parasitaemia ranging from 724-6,000 mf/ml. A positive correlation was observed between mosquito size (measured by wing length) and egg production in uninfected females. However, this relationship did not exist in W. bancrofti infected mosquitoes. This change is unlikely to be the result of changes in blood ingestion as no significant difference was found when infected and uninfected females were compared. Variation in egg production observed between trials could not be associated with parasite density in the blood. These results suggest infection with W. bancrofti may disrupt the relationship between mosquito size and egg production during the first gonotrophic cycle of C. quinquefasciatus such that fecundity is sometimes reduced. However, this overall affect is variable and many groups of mosquitoes do not respond in this way.

Life tables and reproductive parameters of Lutzomyia spinicrassa (Diptera: Psychodidae) under laboratory conditions

Lutzomyia spinicrassa is a vector of Leishmania braziliensis in Colombia. This sand fly has a broad geographical distribution in Colombia and Venezuela and it is found mainly in coffee plantations. Baseline biological growth data of L. spinicrassa were obtained under experimental laboratory conditions. The development time from egg to adult ranged from 59 to 121 days, with 12.74 weeks in average. Based on cohorts of 100 females, horizontal life table was constructed. The following predictive parameters were obtained: net rate of reproduction (8.4 females per cohort female), generation time (12.74 weeks), intrinsic rate of population increase (0.17), and finite rate of population increment (1.18). The reproductive value for each class age of the cohort females was calculated. Vertical life tables were elaborated and mortality was described for the generation obtained of the field cohort. In addition, for two successive generations, additive variance and heritability for fecundity were estimated.

Assisted reproductive technology and obstetric outcome in couples when the male partner has a chronic viral disease.

BACKGROUND Assisted reproductive technology (ART) with washed semen can achieve pregnancy with minimal risk of horizontal and vertical transmission of chronic viral diseases (CVD) such as human immunodeficiency virus (HIV), hepati- tis C virus (HCV) and hepatitis B virus (HBV) among serodiscordant couples. How- ever, few studies have been made of the use made by these couples of ARTs or of the obstetric results achieved. MATERIALS AND METHODS In this retrospective study, 93 men who were seropositive for HIV, HCV or HBV and who underwent assisted reproduction treatment at our centre (Hospital Universitario Virgen de las Nieves, Granada, Spain) were included. Washed semen was tested to detect viral particles. Non-infected women were tested before and after each treatment, as were the neonates at birth and after three months. RESULTS A total of 62 sperm samples were washed, and none were positive for the detec- tion of viral molecules. Semen samples from 34 HBV positive males were not washed since the female partner had immunity to hepatitis B. In total, 38 clinical pregnancies were achieved (22% per cycle and 40.9% per couple) out of 173 cycles initiated, and 28 births were achieved (16.2% per cycle and 30.1% per couple), producing 34 live births. The rate of multiple pregnancies was 21.4%. Obstetric and neonatal results were similar in the groups of couples studied. At follow-up, no seroconversion was detected in the women or neonates. CONCLUSION Sperm washing and intracytoplasmic sperm injection are shown to be a safe and effective option for reducing the risk of transmission or super infection in serodiscordant or concordant couples who wish to have a child. Pregnancies ob- tained by ART in couples when the male is CVD infected achieve good obstetric and neonatal results.

Biological cycle of Tenuipalpus heveae Baker (Acari, Tenuipalpidae) on leaflets of three rubber tree clones

Life cycle of Tenuipalpus heveae Baker (Acari, Tenuipalpidae) on leaflets from three rubber tree clones. The biological cycle of Tenuipalpus heveae Baker, 1945 (Tenuipalpidae), a potential rubber tree pest mite, was studied by the observation of individuals reared on leaflets of the clones GT 1, PB 235 and RRIM 600, in controlled environmental conditions. Three daily observations were done of 60 eggs on leaflets from each clone in order to verify the development of immature stages and the female oviposition. The fertility life table was constructed based in the collected data. Mites reared on PB 235 had faster rate of development, requiring less time in days, to double its population in number (TD), and had the highest values for egg production, female longevity, net reproductive rate (Ro), intrinsic rate of natural increase (r m) and finite rate of increase (λ). Lower reproductive values and the longest time necessary to reach adult stage were recorded for the mites on GT 1. In all studied clones, the deutonymphal phase had the highest viability, while the larval phase had the lowest, highlighted by the survivorship curve that indicated high mortality during this life stage. The clone PB 235 allowed the most suitable conditions for the development of T. heveae, followed by RRIM 600, while GT 1 was the less suitable substratum to rear this mite species.

Biology and reproductive capacity of Spodoptera eridania (Cramer) (Lepidoptera, Noctuidae) in different soybean cultivars

This study aimed to evaluate the development, survival and reproductive capacity of Spodoptera eridania in four soybean cultivars. The experiment was conducted in the laboratory, in a climatic chamber at 25 °C ± 1 °C, 70 ± 10% relative humidity and 12 h photophase. The cultivars used were: FMT Tabarana, BRS/MT Pintado, FMT Tucunaré and Monsoy 8757, all conventional cultivars with medium cycles. All cultivars tested allowed the development of S. eridania. However, Monsoy 8757 was the cultivar that most affected the prolonged in the duration larval, pupal and total cycle, showed lower pupal weight as well as reduction in the intrinsic rate increase. These results contribute to the management of this species in regions of outbreaks in soybean areas.

Mating does not influence reproductive investment, in a viviparous lizard.

Mating is crucial for females that reproduce exclusively sexually and should influence their investment into reproduction. Although reproductive adjustments in response to mate quality have been tested in a wide range of species, the effect of exposure to males and mating per se has seldom been studied. Compensatory mechanisms against the absence of mating may evolve more frequently in viviparous females, which pay higher direct costs of reproduction, due to gestation, than oviparous females. To test the existence of such mechanisms in a viviparous species, we experimentally manipulated the mating opportunity of viviparous female lizard, Lacerta (Zootoca) vivipara. We assessed the effect of mating on ovulation, postpartum body condition and parturition date, as well as on changes in locomotor performances and body temperatures during the breeding cycle. Female lizards ovulated spontaneously and mating had no influence on litter size, locomotor impairment or on selected body temperature. However, offspring production induced a more pronounced locomotor impairment and physical burden than the production of undeveloped eggs. Postpartum body condition and parturition dates were not different among females. This result suggests that gestation length is not determined by an embryonic signal. In the common lizard, viviparity is not associated with facultative ovulation and a control of litter size after ovulation, in response to the absence of mating.

Ursinia nana (Anthemideae, Asteraceae), and adventive from South Africa which is becoming naturalized in the Iberian Peninsula. Observations about its reproductive biology and fruit dispersal mechanism.

The presence of Ursinia nana, an Anthemideae of South-African origin which has been introduced into the NE Iberian Peninsula, is reported for the fi rst time in Europe. The data offered cover its precise location, morphology, chromosome number, ecology and a population census, as well as its life cycle, fl oral structure, reproductive biology and fruit dispersal mechanisms. Of special note are the clear predominance of autogamy (geitonogamy) over xenogamy as a reproductive system and the large number of fruits produced with high and immediate germinative capacity. These characteristics permit rapid colonization by the introduced species, which can become invasive. However, fruit predation by the ant Messor barbarus points to a natural mechanism that helps regulate population growth and makes biological control possible. Finally its possibilities of expansion in the colonized area and of naturalization in the NE Iberian Peninsula are assessed.

Differential vegetative and reproductive performances among fifteen guinea grass hybrids

The main scope of this work was to detect (Panicum maximum Jacq.) genotype differences as to morphoagronomic and seed quality indices, and to establish character correlations useful for determining vegetative and reproductive trends. Besides the flowering cycle, eight phenological and two seed quality traits were scored in a greenhouse randomized complete block experiment, as follows: plant height (PH), reproductive tiller number/overall tiller number (RTN/OTN), panicle number/reproductive tillers (PN/RT), leaf length (LL), leaf width (LW), panicle length (PL), fresh weight (FW), dry weight (DW), number of seeds/g (NS/G) and seed sample physical purity (SPP). Very-early and early-flowering hybrids consistently showed the highest correlation values among flowering cycle and RTN/OTN (r = -0.59**), PN/RT (r = -0.48**), NS/G (r = -0.88**) and SPP (r = -0.80**) (reproductive parameters) while intermediate and late-flowering hybrids presented the highest values for LL (r = 0.53**), LW (r = 0.60**), PL (r = 0.77**), FW (r = 0.78**) and DW (r = 0.85**) (vegetative traits). The implications of these results for plant breeding and forage management purposes are discussed.

Morphological and morphometric evaluation of prepubertal gilt ovaries, uterine tubes and uterus at different oestrus cycle stages

Studies are performed in developing techniques/procedures that provide greater reproductive performance in farm animals, including pigs. In this sense, the study of gilts reproductive organs at different oestrus cycle stages for assessing the presence of abnormalities and/or other parameters that may affect the future animal fertility is important. In order to evaluate the morphological, morphometric and histomorphometric features of ovaries, uterus and uterine tubes (UTs) characteristics of prepubertal gilts at different oestrus cycle stages, reproductive tracts from 48 animals immediately after slaughter were obtained. After, the structures were dissected and removed, and the ovaries were used for classification of oestrus cycle stage of each gilt in follicular phase (FP) and luteal phase (FL). Then, morphometric evaluations of ovaries, UTs, uterine horns and uterine body were performed. Besides that, medial segments of UTs and uterus were fixed in Bouin solution, processed and included in paraffin, when histological sections of 5.0 micrometers (µm) were obtained and stained with Hematoxylin and Eosin. Histomorphometric analyzes using image capture system and specific software were performed. Afterwards, data were submitted to Student's t test for assessment the statistical differences (P<0.05) between the two different oestrus cycle stages (FP × LP) and between the placement of reproductive structures (right × left antimer). Among the gilts evaluated, 35 were in the FP and 13 in LP. There was no difference (P>0.05) between morphometric parameters of ovaries, UTs and uterus of gilts in FP and LP. Likewise, in respect to the placement of reproductive structures, both in the oestrus cycle stages, as in the general average, there was no difference (P>0.05). Regarding the histomorphometric variables, gilts classified in FP presented a higher (P<0.05) height of glandular and UT epithelium compared to animals in LP. On the other hand, the diameter of endometrial glands was higher (P<0.05) in gilts at LP compared to FP. Furthermore, gilts in LP presented a higher (P<0.05) proportion of endometrium occupied by glands, whereas animals in FP had a higher (P<0.05) proportion of connective tissue and blood vessels. In conclusion, in prepubertal gilts, the histomorphometric parameters as endometrial glands diameter, the height of glandular epithelium and of UT epithelium and the proportion of endometrium occupied by connective tissue, besides the glands and blood vessels varies through the oestrus cycle, possibly under the influence of ovarian steroids.

Characterization of the estrous cycle in Galea spixii(Wagler, 1831)

The Galea spixii inhabits semiarid vegetation of Caatinga in the Brazilian Northeast. They are bred in captivity for the development of researches on the biology of reproduction. Therefore, the aim of this study is characterize the estrous cycle of G. spixii, in order to provide information to a better knowledge of captive breeding of the species. The estrous cycle was monitored by vaginal exfoliative cytology in 12 adult females. After the detection of two complete cycles in each animal, the same were euthanized. Then, histological study of the vaginal epithelium, with three females in each phase of the estrous cycle was performed; five were paired with males for performing the control group for estrous cycle phases, and three other were used to monitor the formation and rupture of vaginal closure membrane. By vaginal exfoliative cytology, predominance of superficial cells in estrus, large intermediate cells in proestrus, intermediate and parabasal cells, with neutrophils, in diestrus and metestrus respectively was found. Estrus was detected by the presence of spermatozoa in the control group. By histology, greater proliferation of the vaginal epithelium in proestrus was observed. We conclude that the estrous cycle of G. spixii lasts 15.8 ± 1.4 days and that the vaginal closure membrane develops until complete occlusion of the vaginal ostium, breaking after few days. Future studies may reveal the importance of this fact for the reproductive success of this animal.

Behavior of RR soybeans subjected to different formulations and rates of glyphosate in the reproductive period

Recent studies indicate that glyphosate applied in post-emergence in RR soybean can eventually cause phytotoxic effects. However, there are many questions that need to be clarified in the scientific and technical contexts, involving the issue of RR soybeans regarding the use of glyphosate. This study has assessed the impact of the application of different doses and formulations of glyphosate in the reproductive period of RR soybean (R1 stage). For that purpose, an experiment in the field was conducted in two harvests (2011/12 and 2012/13), in which a 2 x 5 factorial design was used (formulations versus doses) totaling 10 treatments. In these two experiments the variables related to agronomic performance were: phytotoxicity (7, 14, 21 and 28 days after application), plant height, number of pods per plant, yield and weight of 100 grains (end of soy cycle). The results obtained allowed characterizing phytotoxicity and damages to the height and yield in RR soybean, with increasing rates of glyphosate applied in the reproductive period.

Cycle modulation of insulin-like growth factor-binding protein 1 in human endometrium

Endometrium is one of the fastest growing human tissues. Sex hormones, estrogen and progesterone, in interaction with several growth factors, control its growth and differentiation. Insulin-like growth factor 1 (IGF-1) interacts with cell surface receptors and also with specific soluble binding proteins. IGF-binding proteins (IGF-BP) have been shown to modulate IGF-1 action. Of six known isoforms, IGF-BP-1 has been characterized as a marker produced by endometrial stromal cells in the late secretory phase and in the decidua. In the current study, IGF-1-BP concentration and affinity in the proliferative and secretory phase of the menstrual cycle were measured. Endometrial samples were from patients of reproductive age with regular menstrual cycles and taking no steroid hormones. Cytosolic fractions were prepared and binding of 125I-labeled IGF-1 performed. Cross-linking reaction products were analyzed by SDS-polyacrylamide gel electrophoresis (7.5%) followed by autoradiography. 125I-IGF-1 affinity to cytosolic proteins was not statistically different between the proliferative and secretory endometrium. An approximately 35-kDa binding protein was identified when 125I-IGF-1 was cross-linked to cytosol proteins. Secretory endometrium had significantly more IGF-1-BP when compared to proliferative endometrium. The specificity of the cross-linking process was evaluated by the addition of 100 nM unlabeled IGF-1 or insulin. Unlabeled IGF-1 totally abolished the radioactivity from the band, indicating specific binding. Insulin had no apparent effect on the intensity of the labeled band. These results suggest that IGF-BP could modulate the action of IGF-1 throughout the menstrual cycle. It would be interesting to study this binding protein in other pathologic conditions of the endometrium such as adenocarcinomas and hyperplasia.

Characterization of Actinobacillus pleuropneumoniae antiviral effect against porcine reproductive and respiratory syndrome virus in porcine alveolar macrophages.

Le syndrome reproducteur et respiratoire porcin (SRRP) est la maladie infectieuse la plus économiquement importante de l’industrie porcine. Une étude récente a démontré que le surnageant de culture d’Actinobacillus pleuropneumoniae (App) inhibe l’infection du virus SRRP (VSRRP) in vitro dans des cellules de singe. L’objectif de cette étude est de démontrer l’effet antiviral d’App contre le VSRRP dans les cellules cibles du virus in vivo: les macrophages alvéolaires porcins (MAPs) et d’étudier les mécanismes spécifiques impliqués lors de l’inhibition virale. Les MAPs ont été traités avec App, avant et après l’infection avec le VSRRP. À différents temps post-infection, la réplication et la transcription du génome viral ont été quantifiées. L’expression des interférons (IFN) type I et II, ainsi que le profil protéomique en présence ou absence d’App ont été évalués. L’expression de certaines protéines a été confirmée par immunobuvardage et immunofluorescence (IF). Les résultats ont démontré que l’effet antiviral d’App n’est pas via l’induction des IFN type I et II. App inhibe l’infection virale dans MAPs avant la réplication et la transcription du génome viral, ce qui indique qu’App inhibe précocement le cycle réplicatif viral. Le profil protéomique a révélé qu’App augmentait l’expression de la cofiline, une protéine qui provoque la dépolymérisation de l’actine. De plus, ce phénomène de dépolymérisation a été confirmé par IF. Le traitement des MAPs avec la cytochalasin D (un composé qui provoque la fragmentation des microfilments) a démontré que comme pour App, cette drogue inhibe la réplication virale. Les résultats obtenus suggèrent que l’effet antiviral d’App est via l'activation de la cofiline et dépolymérisation de l’actine, affectant probablement l’endocytose du VSRRP.

The reproductive response of rams to thyroidectomy: mediation by impaired inhibin feedback rather than a change in LH pulsatility

A series of experiments was conducted to examine the mechanism by which removal of the thyroid glands in seasonally suppressed rams brings about rapid testicular growth. In the first experiment, thyroidectomy at the nadir of the testicular cycle (late winter) initiated testis growth without any detectable change in the extent of spermatogenesis compared with sham-operated controls. The serum concentration of FSH, but not LH, was also markedly increased by thyroidectomy. In the second experiment, serum FSH concentration was again increased by thyroidectomy in late winter but there was no effect of thyroidectomy on LH concentration, LH pulses (measured in frequent blood samples) or testosterone concentration. Furthermore, there was no evidence of a change in central dopaminergic inhibition of GnRH, as measured by the pulsatile LH response to an i.m. injection of the dopaminergic D-2 agonist bromocriptine or antagonist sulpiride. The rapid increase in FSH concentration occurred despite a markedly increased serum inhibin A concentration in thyroidectomized rams. Therefore, the efficacy of inhibin feedback was examined by testing the FSH-suppressive effect of an inhibin preparation (5 ml charcoal-stripped bovine follicular fluid i.v.) in long-term thyroidectomized and thyroid intact castrated rams. Bovine follicular fluid suppressed FSH concentrations in control rams as expected but in marked contrast, was completely without effect in thyroidectomized animals. In castrated rams, the FSH concentration was only marginally increased by thyroidectomy, indicating that there is a major component of the mediation of the effects of thyroidectomy that is testicular in origin. It was concluded that a reduction in the ability of endogenous inhibin to inhibit FSH release at the pituitary, rather than a hypothalamic mechanism, is the primary cause of the stimulation of testis growth by thyroidectomy.

Sublethal neonicotinoid insecticide exposure reduces solitary bee reproductive success

1. Pollinating insects provide crucial and economically important ecosystem services to crops and wild plants, but pollinators, particularly bees, are globally declining as a result of various driving factors, including the prevalent use of pesticides for crop protection. Sublethal pesticide exposure negatively impacts numerous pollinator lifehistory traits, but its influence on reproductive success remains largely unknown. Such information is pivotal, however, to our understanding of the long-term effects on population dynamics. 2 We investigated the influence of field-realistic trace residues of the routinely used neonicotinoid insecticides thiamethoxam and clothianidin in nectar substitutes on the entire life-time fitness performance of the red mason bee Osmia bicornis. 3 We show that chronic, dietary neonicotinoid exposure has severe detrimental effects on solitary bee reproductive output. Neonicotinoids did not affect adult bee mortality; however, monitoring of fully controlled experimental populations revealed that sublethal exposure resulted in almost 50% reduced total offspring production and a significantly male-biased offspring sex ratio. 4 Our data add to the accumulating evidence indicating that sublethal neonicotinoid effects on non-Apis pollinators are expressed most strongly in a rather complex, fitness-related context. Consequently, to fully mitigate long-term impacts on pollinator population dynamics, present pesticide risk assessments need to be expanded to include whole life-cycle fitness estimates, as demonstrated in the present study using O. bicornis as a model.