Estresse término na reprodução de vacas leiteiras

Climate change in tropical countries, like Brazil, causes major problems in dairy production due to an increase of heat stress effects. In recent years, milk production in Brazil increased 36.07%. The Southeast region remains a leader in production with herds of high producing Holstein cattle (mostly), which is more susceptible to heat stress. Thermal stress decreases fertility in direct and indirect ways. Conception rates are reduced of 40-60% during cooler months of the year and 10-20% in the warmer months. Negative effects of heat stress involve changes in reproductive hormones, follicular development, oocytes, and embryos, and decreased dry matter intake. Several studies discuss change in reproductive hormones, such as reduction in plasma concentration of GnRH, LH, and oestradiol, which lead to decreased detection of estrus and ovulation. Various methods are being studied to bypass these negative effects and increase the fertility of dairy cows under heat stress. Cooling systems are the most advantageous and can be associated with technologies such as ET and TAI

Criopreservação de embriões bovino produzidos in vitro: estado da arte

In the last years, the embryo in vitro production for every domestic species and mainly for bovine has attained a notorius status. This reproductive biotechnical procedure associate with ultrasound-guided ovum pick up (OPU) has been more and more incorporated and spread in our cattle herds, ranking up Brazil already at the top of the list in number of in vitro embryo produced. Some significant advantages provided, such as the possibility of using the premature or pregnant animals oocytes, without necessarily requiring the use of hormonal treatment, to make it possible to generate pregnancy at a shorter period of time, the rationalization in the use of semen and optimization in the use of sexed semen were determinant factors for OPU/IVP to reach this outstanding position. Nevertheless, right now the possibility of IVP embryo cryopreservation, just now is the biggest impediment for maximizing the use of this biotechnology, due to both lack of efficient methods and low laboratory produced embryo cryotolerance. Nowadays, the most used methods of IVP embryo cryopreservation are: slow freezing and vitrification. Traditionally, slow freezing is still the most used methods for in vivo and in vitro produced embryo cryopreservation. However, more recently vitrification - although still not commercially used in large scale - has been presenting satisfactory results in IVP embryo cryopreservation, according to searches

Correlação entre aneuploidia cromossômica em espermatozóides e taxa de implantação embrionária: subtitulo

Infertility is directly related to chromosomal abnormalities in germ cells. Among them, the aneuploidies are the most frequent chromosomal abnormalities and responsible for embryo implantation failures, miscarriages, fetal losses and newborns with congenital malformations, mental disability and neuropsychomotor developmental delay. Male patients with normal somatic karyotype may present different rates of aneuploidies in sperm, resulting in abnormal embryos. This study aimed to correlate the frequency of chromosomal aneuploidies in spermatozoa with embryo implantation rate in couples undergoing assisted reproductive techniques. The methodology has included chromosomal analysis by GTG banding and molecular cytogenetic study using Fluorescent In Situ Hybridization technique for evaluation of chromosomes 9, X and Y in germ cells of 22 patients referred to the Human Reproduction Service of the Clinical Hospital FMRP-USP. Embryo implantation rates were determined by hormonal evaluation in maternal peripheral blood and ultrasound confirmation. Two patients presented abnormal karyotype, characterized by polymorphism of the heterochromatic region of the long arm of chromosome 9 and a satellite in the short arm of chromosome 22. Both alterations, usually considered variants of normality, have been related to infertility phenotype and miscarriages. Significant differences were detected between couples who presented pregnancy (group 1) and couples with embryo implantation failure (group 2), with higher frequency of aneusomy and diploidy of chromosome 9, as well as total aneuploidy in sperm of group 2 patients. Our results suggest a correlation between aneuploidy and embryo implantation rates, since the infertile group with reproductive failure has showed higher frequency of aneuploidy. Screening for aneuploidies detection in male germ cells should be included in order to decrease embryo implantation failures, miscarriages and fetuses with chromosomal ...

Indução de parto em bovinos: Princípios e aplicações

Currently, Brazil has one of the largest cattle herds worldwide. In order to keep that milk and meat were introduced reproductive biotechnologies such as artificial insemination, embryo transfer and in vitro fertilization. In certain situations the technique may have undesired effect, for example, the production of calve calves due to the very large increase in the gestation period when performed in vitro fertilization. To avoid this problem we perform the induction of labor in order to prevent the product is longer the womb. This induction can also be made in case of diseases that compromise the life of the mother, twin pregnancy an abnormal size calf. The administration of short acting steroids, prostaglandins, association of short acting steroids and prostaglandins and association of short acting steroids, prostaglandins and long-acting corticosteroids are some of the possibilities of induction

Fatores que interferem nas taxas de recuperação embrionária em éguas

The success in implementing an embryo transfer program derives from many factors. The embryo recovery rate is one of the most important factors, and allows the transfer to the recipient mare. This rate comes from a group of elements such as donor´s characteristics, collection date, reproductive management, semen quality, technician skill. Mainly because of the great importance of this direct interference on the results of an embryo recovery program, this study aimed to review the factors involved in embryo recovery rates in donor mares during an embryo transfer, suggesting some ways of improving these results

Alterações metabólicas e morfométricas induzidas por hipóxia em Gallus gallus

Pós-graduação em Zootecnia - FCAV

Avaliação da taxa de concepção de novilhas e vacas (Bos taurus x Bos indicus) com o uso de sêmen sexado na inseminação artificial ou embriões produzidos in vivo e in vitro

Pós-graduação em Medicina Veterinária - FCAV

Controle e estimulação de crescimento folicular em doadoras da raça holandesa para a produção in vitro de embriões

Pós-graduação em Medicina Veterinária - FCAV

Efeitos de diferentes inibidores da meiose sobre a maturação in vitro de oócitos bovinos e subsequente tolerância dos embriões a vitrificação

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

Maturação e aquisição de tolerância à dessecação de sementes de Annona emarginata (Shltdl.) H. Rainer

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

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

Frequência e perfil de gestantes com toxoplasmose em uma unidade de saúde de Matão - SP

Congenital toxoplasmosis is a serious public health case, for it causes irreversible damage to the embryo/fetus, which may cause its death. The identification and the care to pregnant women with suspect acute toxoplasmosis (IgM+) is performed in prenatal monitoring. This study aimed to measure the incidence and know the profile of positive pregnant women for toxoplasmosis in a Basic Health Unit (BHU) in Matão - SP, between the years 2011 to 2013. This is a retrospective descriptive study, from the medical records of pregnant women attended. The project was approved by the Municipal Departament of Health and BHU was chosen along the Municipal Epidemiological Surveillance. From 2011 to 2013, 189 women began prenatal care in the unit, an annual median of 71(±26.91), of which 17 (8.99%) were positive for the serological test indicative of acute phase (IgM+). The distribution over the trial period was: four cases in 2011, twelve cases in 2012 and one in 2013. Pregnant women IgM positive for toxoplasmosis attend by BHU were: age 24(±5.47) years; color: equally distributed among white, black and brown; as the number of pregnancies: multiparous (2±0.97), most of them with a cesarean delivery as obstetric history and possessed no other risk factors associated with pregnancy (94.12%); gave entrance at BHU with 13.65(±7.35) weeks of gestation and had a median of 5(±2.36) consultation on their prenatal care. The examination for toxoplasmosis was requested as recommended by the Health Ministry (HM) and the medication prescribed was Roxamicina® - spiramycin, as soon as the test results (IgM+) arrived. Of the 17 pregnant women, only 10 completed the pre-natal at BHU - attendance at the postpartum consult (58.8%). Of these, the deliveries were vaginal (55.55%), made preterm with 36.5 weeks of gestation at the Municipal Hospital. The babies were born alive (100%) with the weight of 2.68(±0.77) Kg and required special care hospital scope. From the ...

Otimização do meio de transporte de oócitos bovinos destinados à produção in vitro de embriões

Pós-graduação em Medicina Veterinária - FCAV

Principais causas de perdas gestacionais durante o período embrionário em éguas

A perda embrionária consiste em perda econômica significativa dentro do processo de criação de equinos e representa custos adicionais para os criadores decorrentes das repetidas coberturas de éguas durante a temporada reprodutiva, além da diminuição do número de potros nascidos. São consideradas perdas embrionárias aquelas que ocorrem até o 49º dia da gestação e são decorrente de diversos fatores maternos e/ou embrionários. Atualmente, com a utilização da ultrassonografia, pode-se observar a vesícula embrionária a partir do 11º dia pós-ovulação, sendo possível o diagnóstico precoce de tais perdas. Devido ao grande prejuízo econômico na reprodução equina decorrente de perdas gestacionais, o objetivo deste Trabalho de Conclusão de Curso foi realizar revisão de literatura sobre as principais causas da perda embrionária em éguas

Ultrasonography of the conceptus development from days 15 to 60 of pregnancy in non-cyclic recipient mares

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