Dinâmica populacional de Characidium lauroi e C. alipioi (Teleostei, Crenuchidae) na microbacia do Ribeirão Grande, serra da Mantiqueira Oriental, Estado de São Paulo

In low-order streams, the high and variable water flow rates offer both advantages and disadvantages to the life cycle of fishes. Even closely related species living in similar habitats can show differences in life history patterns. Based on oocyte-size distributions, C. lauroi was classified into the fractional spawning type, and C. alipioi into the total spawning type. The absolute fecundity of C. lauroi ranged from 1,313 to 2,925 oocytes; in C. alipioi the absolute fecundity ranged from 2,213 to 25,550 oocytes. The nonparametric Spearman correlation test showed statistical significance between the gonadosomatic index and fecundity for both species. The growth parameters, natural mortality rate and survival rate for females of C. lauroi were: K = 0.68 yr -1, L ∞ = 8.7 cm, t max = 4.4 years, M= 1.62 yr -1, S = 19.79%, and for males: K = 0.78 yr -1, L ∞ = 6.9 cm, t max = 3.8 years, M = 1.89 yr -1, S = 15.11%. The growth parameters, natural mortality rate and survival rate for females of C. alipioi were: K = 0.90 yr -1, L ∞ = 12.2 cm, t max = 3.3 years, M = 1.81 yr -1, S = 16.37%, and for males: K = 0.76 yr -1, L ∞ = 10.1 cm, t max = 3.9 years, M = 1.71 yr -1, S = 18.10%.

Estudo morfológico e histológico dos ovos de seis espécies do gênero Triatoma (Hemiptera: Reduviidae)

The objective of this study was to analyze the morphological and histological characteristics of eggs from six triatomine species in order to obtain a generic and specific characterization of this group of Trypanosoma cruzi vectors and better understand their phylogenetic and taxonomic aspects. The eggs of the respective species came from the collection of the Laboratório de Triatomíneos e Culicídeos da Faculdade de Saúde Pública/USP, from the Insetário do Serviço Especial de Saúde de Araraquara - SESA and from the Triatomine insectary of the Laboratório Nacional e Internacional de Referência em Taxonomia de Triatomíneos (FIOCRUZ), in Rio de Janeiro. Morphological studies were done with optical microscopy and scanning electron microscopy. Histological analyses used only optical microscopy. All of the species analyzed showed a predominance of hexagonal cells. The exchorion of Triatoma breyeri Del Ponte, T. costalimai Verano & Galvão, and T. tibiamaculata (Pinto) consists of unornamented cells, overlapping or slightly separated, with a smooth, padded appearance. Meanwhile, in T. matogrossensis Leite & Barbosa, T. sherlocki Papa, Juberg, Carcavallo, Cerqueira & Barata, and T. williami Galvão, Souza & Lima, the exchorion cells are ornamented on their entire surface with perforations and fissures. Egg histology showed undulations, pores, and orifices. The study helps to expand the generic and specific knowledge of the Triatominae subfamily. The characteristics identified in the exchorion of the eggshells can help separate close species. These new parameters will back the elaboration of future dichotomous keys, help to determine each vector species' role and expand knowledge of the various species.

Effect of mating delay in the ovary of Apis mellifera L. (Hymenoptera, Apidae) queens: Histological aspects

This paper reports the effect of mating delay on the queen Apis mellifera ovaries based on a light microscopy analysis. Soon after a queen emerges from the brood cell, oocytes start to differentiate in the ovaries, but if mating does not occur at the correct age (about 6 days after emergence) cell degeneration begins. Ovaries of 15-day-old virgin queens show extensive disorganization with cell death affecting all types of ovariole cells. Types of cell death and the possible causes are discussed.

Efeitos de diferentes sistemas de cultivo in vitro sobre o crescimento de folículos pré-antrais isolados de ovários de fetos bovinos

The objective of this study is to use different in vitro culture systems of preantral follicles from Nelore breed bovine fetuses in the last gestation quarter. The evaluation of treatments considered the time of growth of isolated follicles. Preantral follicles were mechanically isolated and submitted to the individual culture, for 9 days, in media no supplemented or supplemented with fetal calf serum (FCS), bovine serum albumin (BSA) or synthetic defined supplement substitute of serum KnockoutSR (KNO). We have also evaluated the effects of collagen gel or fetal calf fibroblast monolayer as substratum for in vitro cultures. The increase on the follicular diameter was followed in the first day (0 h), at the 72 h, 144 h and 216 h. Considering cultures of isolated follicles, the results have shown that the association between media supplemented with FCS and collagen gel was significantly more efficient on the increase of the follicular diameter than other treatments. It is not still established a system of appropriate cultivation that sustains the differentiation and multiplication of the granular cells and that maintains the contact of the same ones with the oocyte to provide molecules and factors that supply the metabolic demand. We also understand that our results also represent another promising step on the search for the ultimate system of in vitro culture of preantral follicles from bovines.

Effects of atrazine on female Wistar rats: Morphological alterations in ovarian follicles and immunocytochemical labeling of 90 kDa heat shock protein

Fertility in female mammals may be affected by a variety of endocrine disrupters present in the environment. Herbicide atrazine is an example of endocrine disrupter employed in agriculture, which disrupts estrous cyclicity in rats. Aiming to characterize morphologically the effect of low and sublethal doses of atrazine on the ovaries of Wistar rats, in an effort to determine the possible intrafollicular target site through which this herbicide acts adult females were submitted to both subacute and subchronic treatments. Additionally, immunocytochemical labeling of 90 kDa heat shock protein (HSP90) was performed in order to evaluate the role played by this protein in the ovary, under stressed conditions induced by herbicide exposure. The results indicated that atrazine induced impaired folliculogenesis, increased follicular atresia and HSP90 depletion in female rats submitted to subacute treatment, while the subchronic treatment with low dose of atrazine could compromise the reproductive capacity reflected by the presence of multioocytic follicle and stress-inducible HSP90. © 2007 Elsevier Ltd. All rights reserved.

Localization of myosin-Va in subpopulations of cells in rat endocrine organs

Myosin-Va is a Ca 2+/calmodulin-regulated unconventional myosin involved in the transport of vesicles, membranous organelles, and macromolecular complexes composed of proteins and mRNA. The cellular localization of myosin-Va has been described in great detail in several vertebrate cell types, including neurons, melanocytes, lymphocytes, auditory tissues, and a number of cultured cells. Here, we provide an immunohistochemical view of the tissue distribution of myosin-Va in the major endocrine organs. Myosin-Va is highly expressed in the pineal and pituitary glands and in specific cell populations of other endocrine glands, especially the parafollicular cells of the thyroid, the principal cells of the parathyroid, the islets of Langerhans of the pancreas, the chromaffin cells of the adrenal medulla, and a subpopulation of interstitial testicular cells. Weak to moderate staining has been detected in steroidogenic cells of the adrenal cortex, ovary, and Leydig cells. Myosin-Va has also been localized to non-endocrine cells, such as the germ cells of the seminiferous epithelium and maturing oocytes and in the intercalated ducts of the exocrine pancreas. These data provide the first systematic description of myosin-Va localization in the major endocrine organs of rat. © 2008 Springer-Verlag.

Correlação entre a taxa de fertilização e o fuso meiótico em oócitos humanos: Uma meta-análise

Objective: To investigate the relationship between the presence of meiotic spindle in human oocytes and fertilization rates in ICSI cycles. Methods: Search strategies included online surveys of databases from 1990 to 2008. Nine trials fulfilled the inclusion criteria Results: According to the meta-analysis, the results showed statistically significant higher fertilization rate (p<0.0001) when the meiotic spindle was viewed than when it was not. There was heterogeneity in this comparison. Conclusion: The presence of a birefringent meiotic spindle in human oocytes can predict a higher fertilization rate. This observation has clinical relevance mainly in countries where there is a legal limit on the number of oocytes to be fertilized. Copyright - SBRA - Sociedade Brasileira de Reprodução Assistida.

A síndrome do hiperestímulo ovariano não influencia os resultados clínicos após ciclos de descongelamento de embriões provenientes de ciclos de ICSI

Objective: The objective of this study was evaluate if the embryos cryopreservation from OHSS patients Intracytoplasmic Sperm Injection (ICSI) cycles could be influence the clinical outcomes when compared to patients who receive oocytes from donors but the endometrium was not prepared and the embryos were cryopreserved. Methods: Fifty eight couples submitted to ICSI cycles in which 26 with OHSS clinical manifestation (OHSS group) and 32 couples who have received oocytes from donors (control group). The embryos were frozen on day+2 or +3of development. All patients included in this study had embryos crypreserved before the transfer, and in the thawing cycle, only the endometrium preparation was performed. The embryo survival, implantation, pregnancy and miscarriage rates were evaluated in the embryo thawing cycle. Results: There was no difference among the groups in relation to fertilization rate (OHSS: 71.89% ± 15.45, Control: 79.75% ± 21.68, p= 0.234), survival embryos rate (OHSS: 68.85 ± 21.10, Control: 59.53 ± 36.79, p= 0.233), high quality embryos rate (OHSS: 25.20 ± 23.90, Control: 27.40 ± 30.30, p= 0.760), implantation rate (OHSS: 17.9 ± 26.9, Control: 12.5 ± 23.7, p= 0.435), pregnancy rate (OHSS: 38.50, Control: 28.60, p= 0.441) and miscarriage rate (OHSS: 40.00, Control: 25.00, p= 0.332). Conclusion: Our findings suggest that clinical outcomes in freeze and thawing cycles were not affected by the presence of ovarian hyperstimulation syndrome clinical manifestation after controlled ovarian stimulation.

Seleção de espermatozoides para ICSI

The application of assisted reproduction techniques has provided help to many men seeking to father a child, although the current success of these procedures remains suboptimal. Today some protocols allow sperm to be selected according to their ultrastructural morphology or surface molecular characteristics. On the other hand, successful human reproduction relies partly on the inherent integrity of sperm DNA. Therefore, it is now necessary to improve the safety of the sperm selection method. It is urgent to optimize procedures to isolate spermatozoa for ICSI with low risk of DNA damage. In recent years, two technologies have attracted the attention of specialists as methods capable of identifying a spermatozoon with low risk of DNA damage: Ultrastructural morphology sperm selection at high magnification and sperm head birefringence selection. This review analyses these two technologies. © Todos os direitos reservados a SBRA - Sociedade Brasileira de Reprodução Assistida.

Reproductive technology in domestic carnivorous

Background: The delay in development of artificial reproduction techniques on carnivorous could be due to countless reasons, but the lack of commercial interest is probably the most important one. The majority of canines are small structures, canidae are extremely fertile and a great number of species are adapted to domestication or captivity. Finally, the canine gamete physiology presents a difficult adaptation of technology knowledge obtained from other species. Furthermore, domestic felines are animals of company and there is no interest in reproducing them in a large scale, as it has been observed in other domestic animals, however, besides of being a valuable model for the development of in vitro techniques, the domestic cat is also used as an embryo receptor for different species of small wild felines due to physiological similarities among them, in vitro embrionary development, Review: It was reviewed the main insights about the reproductive physiology in female dogs, in vitro oocytary maturation (IVM), pregnancy and conception rate with dogs' frozen/unfrozen semen and PIV in domestic cats. The majority of mammal oocytes restart meiosis spontaneously after ovulation and reaches MII in artificial environment; in an in vitro maturation system in bovines, around 90% of oocytes complete their maturation, although its development capacity can be reduced subsequently. The success of IVM in canidae have been limited, with maturation rate varying from 0 to 58%, usually around 20%. The greatest difficulties include oocyte quality, hormonal environment, protein supplementation, cumulus / oocyte cell interaction, donor breed and age, culture systems, oxygen tension, amino acids, growth factor and sequential means. The freezing process reduces the quality of the semen, firstly because it reduces the number of living sperms and secondly because freezing produces cell modifications that could alter the sperm motility, longevity, integrity of membranes and its fertilizing capacity. Conclusion: Nowadays, several researches are being performed with the aim of increasing viability after dogs' and cats' semen is unfrozen, using extenders, cryoprotectors, freezing and unfreezing curves, addition of antioxidant substances. The aim of this text is to inform about the improvements obtained on the artificial reproduction techniques, emphasizing the oocytary maturation in female dogs, semen cryopreservation and artificial insemination in domestic dogs and cats.

Locus no cromossomo 19 influencia positivamente o número de oócitos recuperados em ciclos estimulados

Objective: To evaluate if identified loci associated with normal age of menopause variation and early menopause can account for the poor response to controlled ovarian stimulation. Methods: A total of 71 patients, with age ≤ 35 years old, undergoing intracytoplasmic sperm injection were tested for three of the four newly identified genetic variants associated with normal variation in menopausal age and early menopause. Patients were divided into two groups: poor responder group (PR group, n=21) and normoresponder group (NR group, n=50). The influence of risk allele frequency on the response to controlled ovarian stimulation (COS) was evaluated. Logistic regression models were used. Results: There was no significant difference in the incidence of the genetic variants between NR and PR group. The risk allele for chromosome 19 variant (rs4806660) demonstrated a protective effect. The presence of a risk allele, either in homozygosis or in heterozygosis, was associated with an increased response to COS, resulting in an elevated number of follicles (Coef: 2.54, P= 0.041) and retrieved oocytes (Coef: 1.41, P= 0.041). Conclusions: Genetic variants rs244715, rs9379896 and rs4806660 are not risk factors for poor ovarian response. Instead, rs4806660 is associated with higher number of follicles and retrieved oocytes. It could be hypothesized that rs4806660 is associated with an increased response to gonadotrophin stimulus. © Todos os direitos reservados a SBRA - Sociedade Brasileira de Reprodução Assistida.

Time and temperature on the storage of oocytes from jundiá catfish, Rhamdia quelen

The objective of this study was to evaluate the effects of three water and storage temperatures on the oocytes of the jundiá catfish, Rhamdia quelen. A factorial experimental design over time, with treatments completed in triplicate every 48 h, was used (5 × 3 × 3 × 3) to study the exposure of the oocytes to temperatures of 15, 25 and 35. °C and activated with water at 15, 25 and 35. °C each at 0, 45, 90, 135 and 180 minutes post-collection. Linear regression analysis for the response surface model indicated an interaction (p<0.05) between time and temperature of exposure with greater values for fertilization, hatching and normal larvae rates at the time of oocyte collection (70.2 ± 8.4% fertilized oocytes, 66.7 ± 29.4% hatched eggs and 30.3 ± 25.0% normal larvae). According to the statistical model, the water temperature that resulted in the highest fertilization rate was 25.6. °C (p<0.05). The rates of fertilization, hatching and normal larvae correlated positively (p<0.05) with one another, showing that these parameters can be used in the measurement of oocyte quality. Artificial fertilization of oocytes is recommended immediately after collection; if storage is necessary, it should be carried out at 15. °C. © 2011 Elsevier B.V.

Ultrastructure of sheep primordial follicles cultured in the presence of indol acetic acid, EGF, and FSH

The aim of this study was to investigate the ultrastructural characteristics of primordial follicles after culturing of sheep ovarian cortical slices in the presence of indol acetic acid (IAA), Epidermal Growth Factor (EGF), and FSH. To evaluate ultrastructure of primordial follicles cultured in MEM (control) or in MEM containing IAA, EGF, and FSH, fragments of cultured tissue were processes for transmission electron microscopy. Except in the control, primordial follicles cultured in supplemented media for 6d were ultrastructurally normal. They had oocyte with intact nucleus and the cytoplasm contained heterogeneous-sized lipid droplets and numerous round or elongated mitochondria with intact parallel cristae were observed. Rough endoplasmic reticulum (RER) was rarely found. The granulosa cells cytoplasm contained a great number of mitochondria and abundant RER. In conclusion, the presence of IAA, EGF, and FSH helped to maintain ultrastructural integrity of sheep primordial follicles cultured in vitro. © 2011 Evelyn Rabelo Andrade et al.

Influência da raça do touro (Bos indicus x Bos taurus) na tolerância ao estresse térmico calórico de embriões bovinos produzidos in vitro

To better understand the differences related to HS resistance between Bos indicus and Bos taurus, we aim to verify if the HS tolerance is due mostly to the genetic contribution from the oocyte, spermatozoa or both. Oocytes from Nelore and crossbreed Holstein cows (cHST) were collected, matured and fertilized with semen from Nelore (N), Angus (An), Brahman (Bra) and Gir (Gir) bulls. Nine six hours post insemination (hpi), ≥ 16 cells embryos were separated in two groups: control and HS. In control group, embryos were cultured at 39°C, whereas in the HS group, embryos were subjected to 41°C for 12 h, and then returned to 39°C. There was no effect of HS on blastocyst and hatched blastocyst rates in all breeds analyzed. The percentage of oocytes that cleaved and reached morula stage was significantly lower (p < 0.05) in cHST x Gir as compared to the other breeds. Additionally, blastocyst rates was higher in cHST x N than in cHST x An and cHST x Gir (p < 0.05). It was concluded that the oocyte is more important than the spermatozoa for the development of thermotolerance, since the breed of the bull did not influence embryo development after HS.

Mare's folliculogenesis: Assessment of ovarian and perifollicular vascular perfusion by doppler ultrasound

Background: Ultrasound Doppler is a new technology that has recently been used in large animal reproduction. As the conventional ultrasound (B-mode) it is a noninvasive technique, but with the advantage of allows the assessment of the hemodynamic of reproductive tract in real time. The observation of important features of the vascularization and changes that occur during physiological processes that were not previously seen on B-mode encourage a reassessment of the concepts already established on the events of the reproductive physiology of animals and their applications. Review: In attempt to re-understand the equine reproductive physiology and finding practical uses to this new technique, authors showed that, during the follicular deviation, features are observed by Doppler before being observed under B-mode ultrasound like changes in the speed of the blood flow two days before deviation of the follicle size and one day before the increase in blood flow area of the follicular wall. According to another study ovulation is characterized by a decreased blood flow of the follicular wall in the last four hours preceding it, as well as the serration of the granulosa layer and formation of a non vascularized apex, but in our ongoing study, the ability to decrease the vascularity was not found. Very vascularized follicles are associated with higher rates of oocyte maturation and pregnant that does less vascularized follicles in the preovulatory phase. Those follicles that have septated evacuation (or prolonged) showed more vascularization and serration of the granulosa one hour before ovulation than follicles that ovulate normally, and this vascularization includes the apex of the follicle, the follicular wall portion that is not vascularized in normal ovulation. Another study reported that hemorrhagic follicles have better vascularization of the follicular wall on the days preceding ovulation than follicles destined to ovulate. Some authors also showed that anovulatory follicles grow in size at the same rate as ovulatory follicles, but the percentage of vascularization of its wall is much smaller at 35 mm. Another study characterized that the vascular wall of the follicle that results in the first ovulation of the year is much smaller on the day before ovulation than the number of vessels present in a follicle that will ovulate in the middle of the breeding season. In these cases, the use of Doppler ultrasound can help to prevent economic losses as insemination of mares in cycles that are not able of resulting in pregnancy. This review aims to gather the information found in the literature about the characteristics of follicular hemodynamic of mares taking into account moments of deviation in follicle size, ovulation, ovulation failure and follicular viability. Conclusion: The Doppler technology has the potential to provide important information about the follicular environment and thus be used in practice in search of the perfect equine reproductive management, achieving better utilization of genetic material and increasing the financial return. The use of this new tool opens a large area for several interesting studies that will contribute to the knowledge of the physiological events of the mare for that this technique can soon be effectively applied.