Glyphosate impairs male offspring reproductive development by disrupting gonadotropin expression

Sexual differentiation in the brain takes place from late gestation to the early postnatal days. This is dependent on the conversion of circulating testosterone into estradiol by the enzyme aromatase. The glyphosate was shown to alter aromatase activity and decrease serum testosterone concentrations. Thus, the aim of this study was to investigate the effect of gestational maternal glyphosate exposure (50 mg/kg, NOAEL for reproductive toxicity) on the reproductive development of male offspring. Sixty-day-old male rat offspring were evaluated for sexual behavior and partner preference; serum testosterone concentrations, estradiol, FSH and LH; the mRNA and protein content of LH and FSH; sperm production and the morphology of the seminiferous epithelium; and the weight of the testes, epididymis and seminal vesicles. The growth, the weight and age at puberty of the animals were also recorded to evaluate the effect of the treatment. The most important findings were increases in sexual partner preference scores and the latency time to the first mount; testosterone and estradiol serum concentrations; the mRNA expression and protein content in the pituitary gland and the serum concentration of LH; sperm production and reserves; and the height of the germinal epithelium of seminiferous tubules. We also observed an early onset of puberty but no effect on the body growth in these animals. These results suggest that maternal exposure to glyphosate disturbed the masculinization process and promoted behavioral changes and histological and endocrine problems in reproductive parameters. These changes associated with the hypersecretion of androgens increased gonadal activity and sperm production.

Presumed normal ultrasonographic findings of the testis and epididymis of Botos (Inia Geoffrensis)

Fifteen live adult male botos, or Amazon river dolphins (Inia geoffrensis), were examined using ultrasonography during the yearly capture expedition, between October and November 2005, at the Mamiraua Sustainable Development Reserve, within the Brazilian Amazon (3 degrees S, 65 degrees W). All examinations were performed with a Sonosite 180 plus ultrasound unit in conjunction with a 2- to 5-MHz multifrequency transducer convex array 180 Plus/Elite-C60. Age and maturity estimates were determined considering the body length, weight, and external characteristics. In all examinations, the testes were discerned by the presence of a hyperechoic central line, called the mediastinum testis, a landmark for their identification during ultrasonography. No significant differences in echogenicity were detected on the ultrasonographic appearance of the testes among the studied animals. On adult male botos, apparent parenchymal nodulation of the testis was observed on scanning in most of the animals and probably constituted evidence of reproductive maturity. Using the color Doppler technique, blood flow was detected along the mediastinum testis that progressively decreased toward the periphery of this organ. Little blood flow could be identified by color Doppler. Power Doppler allowed better accuracy to identify testicular vessels, their topography, and their differentiation from adjacent structures. Ultrasonographic examination provides useful data for morphologic characterization of the boto's testes. Examination using Doppler techniques was considered a valuable tool to evidence blood flow through the testicular parenchyma.

Placentation in the paca (Agouti paca L)

Background: The paca is a South American rodent with potential as a commercial food animal. We examined paca placenta as part of a wider effort to understand the reproductive biology of this species. Methods: Thirteen specimens between midgestation and term of pregnancy were studied by light and transmission electron microscopy. Results: The placenta is divided into several lobes separated by interlobular trophoblast. Maternal arterial channels and fetal veins are found at the centre of each lobe. In the labyrinth, maternal blood flows through trophoblast-lined lacunae in close proximity to the fetal capillaries. The interhaemal barrier is of the haemomonochorial type with a single layer of syncytiotrophoblast. Caveolae occur in the apical membrane of the syncytiotrophoblast and recesses in the basal membrane, but there is no evidence of transtrophoblastic channels. The interlobular areas consist of cords of syncytiotrophoblast defining maternal blood channels that drain the labyrinth. Yolk sac endoderm covers much of the fetal surface of the placenta. The subplacenta comprises cytotrophoblast and syncytiotrophoblast. There are dilated intercellular spaces between the cytotrophoblasts and lacunae lined by syncytiotrophoblast. In the junctional zone between subplacenta and decidua, there are nests of multinucleated giant cells with vacuolated cytoplasm. The entire placenta rests on a pedicle of maternal tissue. An inverted yolk sac placenta is also present. The presence of small vesicles and tubules in the apical membrane of the yolk sac endoderm and larger vesicles in the supranuclear region suggest that the yolk sac placenta participates in maternal-fetal transfer of protein. Conclusion: The paca placenta closely resembles that of other hystricomorph rodents. The lobulated structure allows for a larger exchange area and the development of precocial young

Primeiro relato de isolamento de Histophilus somni em ovino com quadro de endometrite no Brasil

Este trabalho tem como objetivo relatar um caso de isolamento em cultura pura de Histophilus somni em secreção vaginal de uma fêmea ovina da raça Texel, em propriedade localizada no estado de São Paulo, a qual apresentou histórico de endometrite e infertilidade. No exame clínico específico do aparelho genital, foi observada na vagina secreção de coloração esbranquiçada, com aspecto mucoso e odor fétido. Os exames sorológicos para Brucella ovis, Leptospirose e Neospora caninum resultaram negativos, enquanto o exame para Toxoplasma gondii foi positivo.

LH surge in response to the treatment with GnRH analog or estradiol in ovariectomized buffaloes with or without progesterone pre-exposition

The aim of the present study was to evaluate the LH surge after EB (estradiol benzoate) or GnRH administration with or without P4 (progesterone) pre-exposure in ovariectomized (OVX) buffalo cows. Females were randomly assigned to receive an intravaginal P4 device (D0–D9). They were then given EB 24 h or GnRH 36 h post-P4 device removal (factorial 2×2, n=6 per group). Blood collection for LH measurement began 36 h after the P4 device removal and continued at 3 h intervals. The area under the LH curve (AUC; 30.2 ng2 and 13.41 ng2; P=0.007) and the area of the LH peak (AP; 19.0 ng2 and 8.9 ng2; P=0.009) were greater for EB than GnRH. We did not observe an effect of P4 pre-exposure on the AUC and AP. Furthermore, there was no interaction between P4 pre-exposure and EB or GnRH treatment on the AUC and AP. However, there was an interaction (P<0.01) between P4 pre-exposure and the type of inducer (EB or GnRH) to release a preovulatory-like LH surge at the beginning (BP), final (FP) and time (TP) of the LH peak. The P4 pre-exposure anticipated the BP (2.5 and 7.4 h), TP (6.0 and 12.0 h) and FP (11.5 and 17.1 h) when EB was used to induce a preovulatory-like LH surge (P<0.01). However, there was no effect of P4 pre-exposure on BP (0.4 and 0.4 h), TP (3.0 and 3.0 h) and FP (5.9 and 6.1 h) with GnRH treatment. There was also no effect of the pre-exposure to P4, type of inducer or interaction on the amplitude of the LH peak. We concluded that EB therefore led to greater LH release than GnRH, and pre-exposure to P4 before EB administration anticipated the preovulatory-like LH surge in buffalo cows.

Storage of bovine reproductive tissues and RNA extracts on ice for 24h or repeated freeze–thaw cycles do not affect RNA integrity

The aims of this study were to test (i) the effect of time of tissue and RNA extracts storage on ice and (ii) the effect of repeated freeze–thaw cycles on RNA integrity and gene expression of bovine reproductive tissues. Fragments of endometrium (ENDO), corpus luteum (CL) and ampulla (AMP) were subdivided and incubated for 0, 1, 3, 6, 12 or 24 h on ice. RNA extracts were incubated on ice for 0, 3, 12 or 24 h, or exposed to 1, 2, 4 or 6 freeze–thaw cycles. RNA integrity number (RIN) was estimated. Expression of progesterone receptor (PGR) and cyclophilin genes from RNA extracts stored on ice for 0 or 24 h, and 1 or 6 freeze–thaw cycles was measured by qPCR. Tissue and RNA extract incubation on ice, and repeated freeze–thaw cycles did not affect RIN values of RNA from ENDO, CL or AMP. Storage on ice or exposure to freeze–thaw cycles did not affect Cq values for PGR or cyclophilin genes. In conclusion, neither generalized RNA degradation nor specific RNA degradation was affected by storage of tissue or RNA extracts on ice for up to 24 h, or by up to 6 freeze–thaw cycles of RNA extracts obtained from bovine ENDO, CL and AMP.

Morphology of accessory genital glands of spotted paca(Agouti paca Linnaeus, 1766)

The spotted paca is the second largest rodent in Brazil, where it is of great economic interestin impoverished regions in view of its prominence as a low-cost source of protein. Littleis known about the morphology of the accessory genital glands of this species. Thus, westudied the position and morphology of the genitals in ten adult male spotted pacas. Theanimals were divided into two groups, five animals were used for fixing of samples in 10%aqueous formaldehyde for macroscopic studies and the other five animals were designatedfor microscopic analysis. These were arranged in pairs and had the vesicular, prostate,coagulating and bulbourethral glands identified, being structured as mucous glands, whichlead into the pelvic urethra. It was concluded that the accessory genital glands found in thepaca are the same as those found in most rodents, showing similar histological aspects

Manipulation of the periovulatory sex steroidal milieu affects endometrial but not luteal gene expression in early diestrus Nelore cows

In beef cattle, the ability to conceive has been associated positively with size of the preovulatory follicle (POF). Proestrus estradiol and subsequent progesterone concentrations can regulate the endometrium to affect receptivity and fertility. The aim of the present study was to verify the effect of the size of the POF on luteal and endometrial gene expression during subsequent early diestrus in beef cattle. Eighty-three multiparous, nonlactating, presynchronized Nelore cows received a progesterone-releasing device and estradiol benzoate on Day–10 (D 10). Animals received cloprostenol (large follicle-large CL group; LF-LCL; N ¼ 42) or not (small follicle-small CL group; SF-SCL; N ¼ 41) on D 10. Progesterone devices were withdrawn and cloprostenol administered 42 to 60 hours (LF-LCL) or 30 to 36 hours (SF-SCL) before GnRH treatment (D0). Tissues were collected at slaughter on D7. The LF-LCL group had larger (P < 0.0001) POF (13.24 0.33 mm vs. 10.76 0.29 mm), greater (P < 0.0007) estradiol concentrations on D0 (2.94 0.28 pg/mL vs. 1.27 0.20 pg/mL), and greater (P < 0.01) progesterone concentrations on D7 (3.71 0.25 ng/mL vs. 2.62 0.26 ng/mL) compared with the SF-SCL group. Luteal gene expression of vascular endothelial growth factor A, kinase insert domain receptor, fms-related tyrosine kinase 1, steroidogenic acute regulatory protein, cytochrome P450, family 11, subfamily A, polypeptide 1, and hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid deltaisomerase 7 was similar between groups. Endometrial gene expression of oxytocin receptor and peptidase inhibitor 3, skin-derived was reduced, and estrogen receptor alpha 2, aldo-keto reductase family 1, member C4, and lipoprotein lipase expression was increased in LF-LCL versus SF-SCL. Results support the hypothesis that the size of the POF alters the periovulatory endocrine milieu (i.e., proestrus estradiol and diestrus progesterone concentrations) and acts on the uterus to alter endometrial gene expression. It is proposed that the uterine environment and receptivity might also be modulated. Additionally, it is suggested that increased progesterone secretion of cows ovulating larger follicles is likely due to increased CL size rather than increased luteal expression of steroidogenic genes.

Condição corporal ao parto e produção de leite sobre o desempenho reprodutivo de vacas holandesas em lactação

O objetivo, neste estudo, foi avaliar os efeitos da condição corporal ao parto e da mudança de condição corporal sobre o desempenho reprodutivo de vacas leiteiras após o parto. Para tanto, 51 vacas holandesas, de 30 dias pré-parto até 150 dias após o parto, foram distribuídas aleatoriamente de acordo com a condição corporal ao parto nas classes 1 (condição corporal maior ou igual a 3,25) e 2 (condição corporal menor ou igual a 3,0). Dentro das classes de condição corporal ao parto, os animais foram distribuídos quanto à mudança de condição corporal (Categoria 1, igual ou menor que -0,50 e Categoria 2, igual ou maior que -0,75) e à média da produção de leite ajustada para 3,5% aos 150 dias (Grupo 1 = 22,61 e Grupo 2 = 31,65 kg/dia). Não houve diferenças da condição corporal ao parto e da produção de leite ajustada para 3,5% sobre o intervalo parto primeiro estro, intervalo parto primeiro serviço, período de serviço, número de serviço / concepção e taxa de gestação aos 150 dias de lactação. Vacas que ao parto apresentaram média de escore de condição corporal de 3,40 e 2,79 tiveram semelhante desempenho reprodutivo pósparto. Em relação à produção de leite ajustada para 3,5%, vacas com produção média de 22,61 e 31,65 apresentaram similares resultados. A mudança de condição corporal não influenciou o intervalo parto primeiro serviço, o período de serviço e o número de serviço por concepção, mas apresentaram maior intervalo parto primeiro estro e menor taxa de gestação

Dynamics of cell and tissue genesis in the male reproductive system of ticks (Acari: Ixodidae) Amblyomma cajennense (Fabricius, 1787) and Amblyomma aureolatum (Pallas, 1772): a comparative analysis

Ticks are classified into three families: Argasidae, Ixodidae, and Nutalliellidae. The taxonomy and phylogeny within Ixodidae are still discussed by the specialists, thus requiring further studies. Amblyomma cajennese and Amblyomma aureolatum (Brazil) belong to two species complexes known as “cajennese” and “ovale”, respectively, and are directly related to the transmission of the Brazilian spotted fever. This confirms the medical and veterinary significance of these species, as well as the need for further morphological studies that will bring a better understanding of their taxonomy, phylogeny, and control. In this context, the present study aimed to characterize the morphology of the male reproductive system of A. cajennese and A. aureolatum when unfed and after 4 days of feeding, thereby seeking to: (a) distinguish the two species or “complexes”, and (b) study an internal system which has the potential to be targeted by acaricides. Therefore, males from both species (unfed and after 4 days of feeding) were cold-anesthetized, dissected, and had their reproductive systems removed for histological analysis. The results showed that the morphology of the male reproductive system is generally similar between both species, like in other Ixodidae ticks, exhibiting a multilobed accessory gland complex related to seminal fluid secretion, a pair of vasa deferentia and a pair of testes housing germ cells (spermatocytes) in different stages. The main differences were found in the development of the accessory gland complex cells and germ cells, showing that the maturation of the male reproductive system starts later in A. aureolatum, when compared to A. cajennese. However, during the blood meal, A. aureolatum development is increased, thus making germ cell maturation and gland complex activity higher than in A. cajennese. This study shows the differences in the development of the male reproductive systems of both species, while providing information that can assist in the establishment of new control methods.

Novos desafios da pesquisa em nutrição e produção animal.

Os organizadores autorizam a reprodução total ou parcial deste trabalho, para qualquer meio convencional ou eletrônico, para fins de estudo e pesquisa, desde que citada a fonte.

Bem estar animal na bovinocultura leiteira

O bem-estar animal é uma ciência que está sendo abordada a nível mundial, sob diferentes ângulos, em grande parte das atividades humanas que envolvem animais. No caso dos animais de produção, a preocupação em produzir de forma ética respeitando o bem-estar dos animais levou a construção de regulamentações e leis que regem a produção animal em diversos países do mundo permeada de desafios. Neste século XXI, mais precisamente em 2011, não se encontrou ainda um ponto de convergência, sob o aspecto da senciência e sob o ponto de vista da produção. No Brasil o assunto é relativamente recente, a disciplina de bem-estar animal na maioria das universidades é optativa, inclusive na Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo (FMVZ-USP). Há a ausência de um foco que conferira uma melhor organicidade e direção entre as disciplinas, seja de produção animal ou mesmo de pequenos animais, silvestres ou de laboratório. Embora existam sociedades protetoras dos animais que esbarram no formalismo acadêmico e, a academia que por sua vez esbarra na anarquia e nas ideias encruadas ou radicais de muitas organizações que tratam deste tema, faz-se necessário unir e trazer essas ideias para a ciência do bem-estar animal, ou seja, intermediar sem pedantismo acadêmico o diálogo na busca da sabedoria, na alegria do respeito aos direitos dos animais e aos seres humanos. O objetivo desta revisão é enfatizar a importância do bem-estar na produção leiteira, atividade praticada amplamente em nosso país.

Emissão de gases de efeito estufa (GEE) pela pecuária: situação e perspectivas para criação de um mercado de crédito de carbono

O mercado mundial de carbono desenvolveu-se rapidamente com a ratificação do Protocolo de Quioto, sendo considerado como base para a implantação deste mercado. O objetivo do presente estudo foi analisar a situação e perspectivas da emissão de gases de efeito estufa (GEE) pela pecuária, e a possível criação de um mercado de crédito de carbono. Pelos dados levantados, pode-se afirmar que o Brasil tem um grande potencial para a criação deste mercado, por possuir o maior rebanho bovino comercial do mundo e importante participação na emissão de GEE, principalmente o metano. Com um horizonte de crescimento para o setor, a melhora da eficiência técnica e a utilização dos preceitos de sustentabilidade são fatores importantes para quem almeja um desenvolvimento sólido e sustentável.