Utilização de gonadotropina coriônica equina em protocolos de inseminação artificial em tempo fixo em bovinos de corte

Current cattlemen must seek methods to maximum reproductive efficiency of their beef herds, making the business competitive and enhancing greater profitability. For the cow-calf producers, efficiency translates into more cows producing one calf every year. Fixed-time artificial insemination (TAI) is one of several technologies that producers utilize to reach this goal. Postpartum anestrus is one of the biggest obstacles to overcome in order to obtain suitable results at the end of the breeding season. The TAI protocols are efficient in re-establishing cyclicity in noncycling cows during the postpartum period, streamlining the use of labor on farms, allowing the use of artificial insemination (AI) on a large scale, and introducing superior genetics to the herd. The protocols that are most commonly used in Brazil are based on progesterone (P4) releasing devices that prevent premature estrus and ovulation; and estradiol (E2) to synchronize the initiation of a new follicular wave. In such protocols, administration of equine chorionic gonadotropin (eCG) helps the development of the follicle, increases ovulation rate, improves the endocrine and uterine environment during proestrus and diestrus, and improves fertility. The use of eCG in TAI protocols for suckled cows, non-lactating cows and heifers increases the pregnancy rate allowing more calves at the end of the breeding season and higher profitability to the cattlemen

Isoeritrólise neonatal eqüina

Equine neonatal isoerythrolysis is a neonatal foals’ illness. Results from the incompatibility of blood type between the foal and the mare and mediated by maternal antibody absorbed by the colostrum against foal’s red blood cells. Characterized by a type ll hypersensitivity reaction, where the exhibition of the organism to a strange antigen, that it takes the sensitization of the lymphocytes B that after the removal of the antigens by the reticule-endothelial system the production of immunoglobulin is decreased, with the formation of cellular immunological will cause the occurrence of the illness in foal of sensitized mares. The most important clinical signs are severe anemia and jaundice, and this illness should be differentiated of other as: hemolysis induced by bacterial toxins, diseases of the hepatobiliary system, disseminated intravascular coagulation and incompatibility in blood transfusions. Like the sensitization happens during the previous incompatible foal’s birth, most cases occur in foals of multiparous mares. However during the first pregnancy the mare can generate a foal with neonatal 7 isoerythrolysis if she have developed placental anomaly in the beginning of the pregnancy which blood cells in her circulation

Avaliação da exposição ao propionato de testosterona em ratas fêmeas in utero e lactação

It is known that exposure to substances in the environment can contribute to various reproductive disorders, especially if such exposure occurs during critical periods of development such as the intra-uterine and postnatal. The female reproductive system may be the target of androgens, both as a result of exposure to environmental chemicals, or by pathological conditions (polycystic ovary syndrome or congenital adrenal hyperplasia).Usually, little attention is given off in relation to the study of androgenic effects in the female reproductive axis. This study aims to evaluate the effects of exposure to androgens on the development, structure and reproductive function in rats whose mothers were exposed to testosterone propionate from gestational day 12 (DG12) after weaning - postnatal day 21 (DPN21) . For this purpose, pregnancy rats were divided into four groups: a control group that received corn oil (vehicle) and three groups receiving testosterone propionate in doses of 0.05 mg / kg / day, 0.1 mg / kg / day and 0.2 mg / kg / day, all under the same experimental conditions. The possible effects of exposure were assessed using reproductive parameters, such as a measure of anogenital distance, count areolas / nipples, age at vaginal opening and first estrus (puberty indicative installation), weight and histological evaluation of the reproductive organs ( uterus and ovaries), weight of the kidneys, liver and pituitary hormone levels, regularity of the estrous cycle, sexual behavior and fertility. Such analysis is important in understanding the effects of androgen exposure on the female genital system, especially on the reproductive potential, and processes that may involve morphofunctional changes. In these experimental conditions, it is concluded that treatment with PT caused reduction in body weight and initial masculinization in females without cubs, however, commit further sexual development

Exposição perinatal ao chumbo e desnutrição intra-uterina, isoladamente ou em associação: efeitos cardiovasculares em ratos recém-desmamados

Plumbism is considered the oldest occupational disease. Among the pathophysiological effects associated with lead (Pb) are cardiovascular disorders. Many diseases that develop later in life are determined during the early stages of life, under the influence of exposure and preferred diet of the mother. Still, one should consider that many environmental contaminants at levels not harmful can determine pathophysiological processes if physical or chemical stressors and/or pathological conditions are present. In this context, the intrauterine malnutrition may represent an additional risk factor in exposure to Pb during pregnancy and lactation. For these reasons, the objective of this study was to evaluate the cardiovascular risk of weaned rats that have suffered perinatal exposure to Pb and intrauterine malnutrition, alone or in combination. After mating, female rats were divided into control (ctrl, ad libitum), food restriction (RA, the same diet 50% of consumption in the control group during pregnancy), exposed to Pb (500 ppm Pb in drinking water during pregnancy and lactation) and association (As, received the last two procedures in combination). Cumulative concentration-effect curves (CECs) to CaCl2 and noradrenaline (NA) were obtained in rings with and without endothelium of the same thoracic aorta from male weaned rats (23-25 days old). Maternal weight, litter weight, weight and number of pups at birth, anogenital distance, arterial blood pressure (ABP) and weight of tissues (kidney, liver, aorta, left ventricle) were evaluated. Changes in vascular reactivity were assessed by the maximum response (MR) and 50% effective concentration (EC50). Data were presented as mean ± SEM. Statistical analysis was performed by multifactorial analysis of variance and Tukey's post test. Body weight of dams did not differ between the experimental groups, except on the...(Complete abstract click electronic access below)

Efeitos da exposição pré-natal ao etanol e ao chumbo, isoladamente e em associação, sobre a pressão arterial e a reatividade da aorta de ratos recém-desmamados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Utiização de altrenogest injetável par o estabelecimento e manutençao da gestação em éguas receptoras de embriões acíclicas

Pós-graduação em Medicina Veterinária - FMVZ

Diagnóstico genético pré-implantacional de embriões equinos

O diagnóstico genético pré-implantacional de embriões equinos já é uma realidade nos Estados Unidos e Argentina. Embora o Brasil seja líder mundial de transferência de embriões equinos, essa tecnlogia ainda está em fase de desenvolvimento, com poucos grupos atuando nessa área no país. O objetivo do presente projeto foi desenvolver a metodologia de micromanipulação e identificação do sexo de embriões equinos a campo. Dessa forma, selecionamos sequências específicas para padronização laboratorial dos ensaios de PCR com amostras de DNA da espécie equina. Os primers que apresentaram maior sensibilidade foram selecionados para a realização da PCR em biópsias embrionárias. Além das análises de biologia molecular, foi desenvolvida a técnica de micromanipulação de embriões equinos. Foram realizadas 105 biópsias de embriões pela técnica de microaspiração, permitindo a identificação do sexo pela técnica de WGA (Whole Genome Amplification) e posteriormente PCR seguido de eletroforese. Os embriões sexados foram transferidos para receptoras sincronizadas, permitindo a avaliação da taxa de concepção dos embriões submetidos à biópsia. Além disso, um embrião foi biopsiado, vitrificado e sexado. Após a identificação do sexo (fêmea) o embrião foi desvitrificado e transferido em receptora criteriosamente selecionada, resultando em prenhez

Proliferação celular em gestações naturais e de conceptos bovinos transgênicos e clonados, que expressam a proteína fluorescente verde (GFP)

Pós-graduação em Ciência e Tecnologia Animal - FEIS

Effect of essential oil from Citrus aurantium in maternal reproductive outcome and fetal anomaly frequency in rats

Citrus aurantium L., commonly known as bitter orange, is widely used in folk medicine, but there is little data in the literature about the s on pregnancy. The aim of the present study was to evaluate the influence of essential oil obtained from fruits of Citrus aurantium on the maternal reproductive outcome and fetal anomaly incidence in rats. Pregnant Wistar rats were randomized into four groups (n minimum = 12 animals/group): G1 = control, G2 to G4 = treated with essential oil from C. aurantium at dose 125, 250 and 500 mg/kg, respectively. Rats were orally treated, by gavage, with plant essential oil or vehicle during pre-implantation and organogenic period (gestational day 0-14). On gestational day 20 the rats were anaesthetized and the gravid uterus was weighed with its contents and the fetuses were analyzed. Results showed that the treated group with 500 mg/kg presented decreased placental weights and placental index, although the treatment with bitter orange essential oil did not show any alteration in maternal reproductive performance, toxicological , changes in ossification sites, and malformation index. In conclusion, the treatment of Citrus aurantium essential oil was not teratogenic and did not alter the maternal reproductive outcome.

Mutações putativo-causais em genes candidatos associadas à fertilidade de bovinos de corte e bubalinos

Pós-graduação em Genética e Melhoramento Animal - FCAV

Efeitos da nutrição no desenvolvimento ovariano fetal durante o início da gestação em vacas Nelore

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influência materna nas caracteristicas morfológicas de ovários e testículos de fetos bovinos da raça Nelore

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fatores que afetam a expressão de estro detectado por monitores de atividade e riscos de concepção em vacas leiteiras lactantes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Seleção e associação genômica para precocidade sexual em bovinos da raça Nelore

Pós-graduação em Genética e Melhoramento Animal - FCAV

Estratégias para aumento da concentração de progesterona durante o desenvolvimento do folículo ovulatório em vacas holandesas em lactação submetidas à inseminação artificial em tempo fixo

Pós-graduação em Zootecnia - FMVZ