Margot Alves Nunes Dode

Brazilian Agricultural Research Corporation (EMBRAPA) | Embrapa · Embrapa Genetic Resources & Biotechnology

Scrotal surface thermography is a non‐invasive method for assessing testicular thermoregulation in stallions; however, few studies have explored the application of this technique concerning the thermal physiology of equine reproductive systems. This study aimed to evaluate the consistency of testicular thermoregulation in stallions over a year usin...

To identify markers of oocyte competence, we compared the biochemical characteristics of fluid and cells from follicles containing oocytes with different capacities to form an embryo. Follicles (5–6 mm) were dissected, and follicular fluid (FF), granulosa cells (GC), cumulus cells (CC) from immature and mature cumulus-oocyte-complexes (COC) were in...

Purpose This study aimed to identify a marker for freezability and in vitro fertility of sperm samples before freezing. Methods Semen was collected from nine Nelore bulls; half of the ejaculate was used for seminal plasma cell–free DNA (cfDNA) quantification, and the other half was cryopreserved. Evaluation of sperm movement using computer-assiste...

Ovócitos utilizados para a produção in vitro de embriões (PIVE) são imaturos e, quandoremovidos dos folículos, retomam automaticamente a meiose, o que leva a uma maturaçãonuclear precoce. Isso afeta a qualidade do ovócito e a sua capacidade de gerar embrião,reduzindo a eficiência da PIVE. O presente trabalho de iniciação científica teve como objeti...

In vitro embryos production from prepubertal heifers can help contribute to breeding programs; however, strategies are necessary to increase their embryo production. The aim of this study was to investigate the effects of two nutritional plans on oocyte recovery, embryo production and growth performance of prepubertal Nelore heifers. Thirty-four Ne...

Despite being the most important form of biotechnology in animal reproduction, artificial insemination was used in about 23% of Brazilian bovine herds in 2021. This is due to the variability of results caused by varying bull fertility and body condition of the cows. This study aimed to correlate the fertility indices of bulls with qualitative attri...

This study aimed to evaluate the effects of donor age on lipid metabolism during in vitro maturation (IVM) of pigs cumulus-oocyte complexes (COCs). We evaluated transcript levels of genes, the percentage of ooplasm occupied by lipid droplets (LD) and evaluated DNA methylation in COCs from sows and prepubertal gilts. Transcript levels of six genes (...

Despite many studies in humans and mice using genome transfer (GT), there are few reports using this technique in oocytes of wild or domestic animals. Therefore, we aimed to establish a GT technique in bovine oocytes using the metaphase plate (MP) and polar body (PB) as the sources of genetic material. In the first experiment, GT was established us...

Somatic cell nuclear transfer (SCNT) is commercially used despite incomplete nuclear reprogramming of the somatic cell nucleus by the enucleated oocyte compromising its efficiency. Oocyte selection is a key factor in increasing this efficiency as its cytoplasm reprograms the differentiated cell. In this study, we adapted a methodology to characteri...

Visto que o Brasil é um importante país no desenvolvimento da produção in vitro de embriões (PIVE) bovinos, a eficiência dessa biotécnica ainda possui algumas limitações como por exemplo, o estresse oxidativo gerado pela produção exacerba de radicais livres. Os radicais livres são produzidos naturalmente pelo metabolismo, mas quando em altas concen...

The effects of seasonality on the reproduction of stallions vary based on the latitude. Although previous studies have shown the influence of seasonality in raw semen quality in south-eastern Brazil, data regarding the influence of seasonality in cooled and frozen stored semen in Brazil is limited. Therefore, in this study, we have analysed if seas...

The objective of this work was to determine the effect of two different feeding plans on quantity and quality of oocytes and in vitro embryo production, as well as on the body development of prepubertal Nellore heifers. After weaning, thirty-three Nellore heifers were divided into two experimental groups and supplemented with two nutritional plans...

The present study aimed to determine whether cumulus cells (CC) biopsy, acquired before or after in vitro maturation (IVM), presents similar gene expression pattern and if would compromises oocyte quality. First, immature cumulus oocyte complexes (COCs) were distributed: (1) maturated in groups (control); (2) individually maturated, but not biopsie...

In the present study, we investigated the spent culture media of in vitro produced (IVP) bovine embryos which did (group Pregnant) or did not (group Non‐pregnant) establish pregnancy after transfer. For that purpose, IVP embryos on D5 were transferred to individual droplets for the last 48 hours of culture. Embryos at the blastocyst stage were then...

Individual embryo culture is the only strategy that allows the tracking of embryos throughout the culture period. However, this procedure leads to lower embryo development. This study aimed to evaluate different alternatives to improve embryo development in a single in vitro production system. First, embryo production was compared between individua...

A produção de embriões in vitro se mostra como uma boa ferramenta de melhoramento genético e multiplicação de animais superiores, visando aumentar a produtividade do plantel. Espécies reativas de oxigênio são um problema comum na produção de embriões in vitro (PIVE), uma vez que produzidos em excesso, podem causar problemas no material genético e l...

We aimed to evaluate if protein source (PS) alterations during IVM affect embryo sex/development and gene expression profile in cumulus cells (CCs). Bovine oocytes were matured and cultured in the presence of FBS or BSA. Then, the PS effect during IVM on gene expression (GPC4, VCAN, GHR, PTGS2, and ALCAM) was determined. CC biopsy was removed befor...

Animal cloning is an important technique used to produce clones from valuable farm animals, to rescue animals in risk of extinction, and for producing transgenic animals. The objective of this work was to evaluate the effects of refrigeration on bovine ear skin as a strategy to transport biological material for long periods of time to isolate viabl...

PurposeThe aim of this study was to analyze the metabolic profiles of blastocoel fluid (BF) obtained from bovine embryos produced in vivo and in vitro.Methods Expanded blastocysts (20/group) that were in vitro and in vivo derived at day 7 were used. BF was collected and analyzed under direct infusion conditions using a microTOF-Q® mass spectrometer...

It is well-established that in vitro culture affects quality, gene expression, and epigenetic processes in bovine embryos and that trophectoderm cells are the most susceptible to abnormalities. These changes have been reported as the main factors responsible for losses observed after transfer of in vitro–produced embryos. The present study aimed to...

To evaluate the addition of antioxidants in extenders on post-thaw bovine semen quality and in vitro embryo production efficiency. Six semen samples were collected from five Holstein bulls. In the experiment I, the samples were diluted with AndroMed® and Bovimix® and added antioxidants glutathione (1.5 and 2.5 mM) and melatonin (0.5 and 1.0 mM). In...

The present study aimed to identify biomarkers to assess the quality of in vitro produced (IVP) bovine embryos in the culture media. IVP embryos on Day (D) 5 of development were transferred to individual drops, where they were maintained for the last 48 h of culture. Thereafter, the medium was collected and the embryos were transferred to the recip...

Maternal nutrition is critical in mammalian development, influencing the epigenetic reprogramming of gametes, embryos, and fetal programming. We evaluated the effects of different levels of sulfur (S) and cobalt (Co) in the maternal diet throughout the pre- and periconceptional periods on the biochemical and reproductive parameters of the donors an...

This study evaluated the effects of three maturation systems, namely invitro (MatV) and invivo (MatS) systems, as well as intrafollicular transfer of immature oocytes (IFIOT; MatT), on the accumulation of lipid droplets in bovine oocytes. Lipids were evaluated using confocal microscopy and transmission electron microscopy. The expression of genes r...

This study aimed to evaluate the effect of scriptaid during pre-maturation (PIVM) and/or maturation (IVM) on developmental competence of bovine oocytes. Cumulus-oocyte complexes (COCs) were submitted to PIVM for 6 h in the presence or absence of scriptaid. COCs were distributed into five groups: T1-IVM for 22 h, T2-PIVM for 6 h and IVM for 22 h, T3...

The maturation kinetics and in vitro fertilization of immature bovine oocytes injected by the intra-follicular oocyte injection (IFOT) technique into pre-ovulatory follicles of previously synchronized cows were evaluated. In Experiment 1, grade I, II and III cumulus-oocyte complexes (COCs) were randomly distributed to one of three Groups: Matvitro2...

In vitro embryo production (IVP) induces excessive production of reactive oxygen species (ROS), which affects blastocyst quality. Therefore, the supplementation of culture media with antioxidants is an alternative to overcome oxidative stress damage. However, there is a growing demand for the use of antioxidant compounds that are more natural and l...

This study aimed to evaluate the effect of natural shade from integrated crop–livestock–forestry (CLF) on the comfort of lactating Gyr cows, as well as their oocyte and embryo quantity and quality. Twenty animals were separated into two experimental groups: grazing under full sun (control) and under natural shade provided by the CLF system. Meteoro...

In this study, we investigated the effects of melatonin supplementation in the culture medium and blastocoel fluid removal (BFR) before vitrification on the quality and viability of in vitro-derived bovine embryos. After fertilization, presumptive zygotes were assigned to one of the following treatments: control, in vitro standard culture (IVC) med...

Sexed cryopreserved semen is widely used in in vitro embryo production (IVEP) for cattle reproduction in Brazil. However, differences between donor breeds regarding variables related to the IVEP process have been reported. This study aimed to evaluate factors affecting the efficiency of IVEP using donors of different genotypes and sexed sperm from...

Valuable female cattle are continuously subject to follicular puncture (ovum pick-up - OPU). This technique is commonly used for in-vitro embryo production, but may result in ovarian lesion. Mesenchymal stem cells (MSC) ameliorate the function of injured tissues, but their use to treat ovarian lesions in cattle has not been established. We investig...

We aimed to analyse the histone acetylation status and expression profile of genes involved in histone acetylation (histone acetyltransferase 1 (HAT1), lysine acetyltransferase 2A (KAT2A), histone deacetylase 1(HDAC1), HDAC2 and HDAC3) in bovine oocytes of different competences during invitro maturation (IVM). Cumulus-oocyte complexes were recovere...

In the present study, four experimental groups were used: fresh embryos, cultured during in vitro maturation and in vitro culture in media supplemented with bovine serum albumin (BSA) (fresh BSA) or fetal bovine serum (FBS) (fresh FBS); and two groups of cryopreserved and thawed embryos, produced under the same conditions (frozen BSA and frozen FBS...

We aimed to elucidate the effects of prostaglandin E2 (PGE2) and prostaglandin F2α (PGF2α) on the in vitro maturation of bovine oocytes. First, cumulus-oocyte complexes were matured in media supplemented with or without PGE2, PGF2α, and PGE2 plus PGF2α for the final 24, 12,or 6 hours of culture. Then, the cumulus-oocyte complexes were matured in th...

Invitro embryo culture induces excessive production of reactive oxygen species (ROS) that impair the quality of produced blastocysts, making them less cryotolerant. Supplementation of culture media with antioxidants would be an alternative to minimise these effects. The present study evaluated the effect of ethanolic extracts obtained from Brazilia...

Many animals with high genetic value have died suddenly without having their germplasm conserved invitro. To simulate tissue transportation from the farm to the laboratory and to determine how long after an animal’s death it is possible to isolate and cultivate fibroblasts to form a cryobank for further use in nuclear transfer, ears of eight bovine...

Cumulative tissue damage and chronic inflammation associated with frequent ovum pickup (OPU) may lead to a progressive reduction in the number and quality of the oocytes recovered, particularly in donors with a high antral follicle count. The aim of this study was to evaluate the effect of an intraovarian treatment with mesenchymal stem cells (MSC)...

Invitro maturation is a key step in invitro embryo production, since its success will depend on the availability of good quality oocytes. Previous studies have shown that it is during this stage that the greatest accumulation of lipid droplets occurs, which is reflected in the amount of lipid present in embryos produced invitro. However, this is no...

The present study evaluated the effects of the blockade of meiosis in bovine oocytes by the cyclin-dependent kinase inhibitors roscovitine (ROS) and butyrolactone-I (BL-I) on nuclear maturation and extracellular signal-regulated kinase 1/2 (ERK1/2), cyclin B1 and p34cdc2 protein expression and localization. We also evaluated ultrastructural changes...

As epididymal sperm (EP) are not exposed to seminal plasma, they are physiologically different from ejaculated spermatozoa (EJ). Therefore, the aim of this study was to morphologically characterize the head of EP recovered from the epididymis tail, and to evaluate if the physiological differences between EP and EJ were also expressed in the head's...

DNA methylation is an essential epigenetic mark for embryo development and can be susceptible to environment factors such as in vitro conditions. The aim of this study was to verify the effect of in vitro culture until Day (D) 14 of the development on the embryo size and DNA methylation pattern of the insulin-like growth factor 2 (IGF2)-imprinted g...

In vitro produced embryos are still sensitive to the freezing process which can be explained, in part, by the high lipid accumulation that characterizes these embryos. Therefore, t we aimed to evaluate the effect of delipidating agents, L‐carnitine and the trans‐10 cis‐12 conjugated linoleic acid (CLA) isomer, on blastocyst development, lipid conte...

This study aimed to characterize the gene expression, lipid composition, and DNA methylation reprogramming during in vitro maturation (IVM) of pig oocytes with different developmental competencies. We used prepubertal gilts and cycling sows as a model to obtain oocytes with different levels of competency. We found that genes involved in lipid metab...

Piau porcine blastocysts were submitted to MALDI-TOF to identify the main phospholipids (PL). After that, in vivo blastocysts (D6) were vitrified (n=52), non-vitrified were used as control (n=42). After warming, blastocysts were in vitro cultured to assess re-expansion and hatching at 24 and 48 hours. Finally, at 48 hours, hatched blastocysts were...

Male and female embryos are known to be different in developmental kinetics, metabolism, gene expression, and epigenetic patterns. Therefore, the objective of this study was to clarify whether the morphological criteria used to select embryos for cryopreservation lead to a deviation in the male:female ratio, and whether vitrification effects vary a...

XIST, in association with the shorter ncRNA RepA, are essential for the initiation of X chromosome inactivation (XCI) in mice. The molecular mechanisms controlling XIST and RepA expression are well characterized in that specie. However, little is known in livestock. We aimed to characterize the DNA methylation status along the 5ʹ portion of XIST an...

The hG-CSF (human Granulocyte Colony-Stimulating Factor) is a growth and stimulation factor capable of inducing the proliferation of bone marrow cells, several types of leukocytes, among other hematopoietic tissue cells. hG-CSF is used in used to treat anomalies that reder a small number of circulating white blood cells, which may compromise the im...

This study aimed to establish a protocol for in vitro embryo production using epididymal sperm (EP). Samples were obtained from ejaculated sperm (EJ) and the epididymis of 7 Gir bulls. First, the effect of heparin (+) on the viability, longevity (Experiment 1) and fertilization rates (Experiment 2) of the EP was evaluated. In experiment 2, a pool o...

Ability to predict male fertility is highly desirable for bulls used in timed-artificial insemination (TAI) to achieve better conception rates, consequently reducing reproductive program costs. Our goal was to correlate different methods of post-thaw semen evaluation with the pregnancy (P/AI) of Nelore (zebu) cows subjected to TAI to identify candi...

The use of mesenchymal stem cells (MSC) in the treatment of diseases has shown significant growth in veterinary medicine, since it is a therapy that can be used to accelerate wound healing, decrease inflammation and modulate the immune system, due to the release of cytokines and growth factors. MSC can be obtained from several adult tissues, howeve...

In the intrafollicular transfer of immature oocytes (TIFOI) the oocytes are aspirated from the donors and transferred to the “ovulators”. Considering that removal of the oocyte from the follicular environment causes the spontaneous meiosis resumption, it is necessary to inhibit this process to avoid oocytes aging. The present study aimed to evaluat...

Intrafollicular transfer of immature oocytes (TIFOI) provides an entirely in vivo environmental condition and may be a good alternative to produce embryos in cattle. However, several aspects of the technique have yet to be established. The aim of this study was to evaluate if the time in which the oocytes remain in the follicle after the TIFOI is e...

During their transit through the female genital tract, spermatozoa bind to oviduct cells, where they are maintained alive for a long period. Although some studies have been carried out to evaluate the effects of the oviduct on spermatozoa, less is known about the effect of spermatozoa on the oviduct. The aim of this study was to evaluate the effect...

Contents Effects of adding different concentrations of melatonin (10 ⁻⁷ , 10 ⁻⁹ and 10 ⁻¹¹ M) to maturation (Experiment 1; Control, IVM + 10 ⁻⁷ , IVM + 10 ⁻⁹ , IVM + 10 ⁻¹¹ ) and culture media (Experiment 2; Control, IVC + 10 ⁻⁷ , IVC + 10 ⁻⁹ , IVC + 10 ⁻¹¹ ) were evaluated on in vitro bovine embryonic development. The optimal concentration of mela...

The objective was to evaluate in vitro nuclear maturation and fecundation kinetics of oocytes injected into preovulatory follicles of synchronized cows using the intra-follicular oocyte injection (IFOI) technique. In experiment 1, 438 immature abattoir-bovine cumulus–oocyte complexes (COC) of grades I, II, and III were randomly allocated to 1 of 3...

The metaphase plate transfer (MPT) between oocytes provides the ability to solve problems that can compromise the success of some assisted reproductive techniques. Among those, the age of the donor, the presence of abnormalities caused by mutation of the mtDNA and cytoplasmic damage due to cryopreservation can be mentioned. In addition, this proced...

Oocyte nuclear maturation is a complex process involving modification of chromatin from the germinal vesicle stage to metaphase II. Studies have reported that oocytes from large follicles have greater developmental capacity than oocytes derived from small follicles, resulting in higher rates of in vitro embryo production. The aim of this study was...

This study assessed the effect of flow cytometry sexing on sperm longevity and the capacity of sperm to bind to oviductal cells. Each ejaculate from four bulls was divided into two fractions: the first was immediately frozen as non sexed sperm (NS) and the second was sexed originating X- and Y-bearing sperm. The fourth treatment had sex-sorted X an...

Na janela do desenvolvimento de mamíferos que inclui a gametogênese e a embriogênese inicial, ocorre o evento da inativação do cromossomo X (ICX) em fêmeas, o qual é regido primariamente por fatores epigenéticos. Na espécie murina sabe-se que o lncRNA transcrito específico do X inativo (XIST), juntamente com um pequeno RNA denominado RepA, são esse...

Oocyte selection using morphological criteria is currently used, but this selection approach has limitations in terms of accuracy, objectivity, and constancy. Therefore, the development of new methods that could allow the identification of molecular markers that can predict the oocyte competency more accurately is needed. Considering that follicula...

For the development of in vitro produced (IVP) as well as in vivo produced bovine embryos, it is extremely important that their energy metabolism works properly because the embryo must be able to metabolize energy substrates that are necessary for producing energy. Lipids play an important role in early embryonic development, acting as source of en...

In an attempt to improve in vitro embryo production, we investigated the effect of FGF10 during in vitro prematuration (PIVM) and in vitro maturation (IVM) on the developmental capacity of bovine oocytes. Five treatments (T) were used as follows: T1) IVM (control): COCs were matured for 22 h; T2) PIVM/IVM: COCs were submitted to 22 h of PIVM and 22...

Purpose: In an attempt to improve in vitro embryo production, we investigated the effect of fibroblast growth factor 10 (FGF10) during in vitro maturation on the developmental capacity of bovine oocytes. Material and methods: Cumulus-oocyte complexes (COCs) were aspirated from follicles of 3-8 mm diameter. After selection, the COCs were matured...

Reproductive biotechnologies such as cooling and freezing semen are employed in order to obtain genetic enhancement in domestic animal breeds. However, cryopreservation of donkey semen, as in several other domestic mammalian species, has not yet reached a standard procedure that provides satisfactory and repeatable results, as in bulls. Despite the...

Assisted reproductive techniques (ARTs) have significantly contributed to animal breeding programs. Similarly, genomics has provided important information and tools to improve the accuracy of selection. However, the greatest benefits of those tools can only be expected when they are combined, allowing animals to be selected accurately early in life...

(Portuguese text) The embryo transfer (ET) is an useful biotechnology in breeding programs for the rapid and efficient dissemination of genetically superior animals that express important economic characteristics. More recently, it has been used to increase productivity. Currently, the options available for embryo production are ET associated with...

This study aimed to evaluate the effect of meiotic arrest using phosphodiesterase type 3A (PDE 3A) inhibitors, cilostamide and C-type natriuretic peptide (NPPC), on pre-maturation (PM) of oocytes to be used in the production of cloned embryos. Nuclear maturation, in vitro embryo production (IVP), somatic cell nuclear transfer (SCNT) and parthenogen...

The aim of this study was to evaluate the effect of adding a combination of insulin, transferrin and selenium (ITS) and l -ascorbic acid (AA) during in vitro maturation (IVM) and in vitro culture (IVC) on in vitro embryo production. To verify the effect of the supplements, cleavage and blastocyst rates, embryo size and total cell number were perfor...

Cryopreservation may lead bovine oocytes to undergo morphological changes and functional damage, due to the high lipid content in the cytoplasm and the formation of reactive oxygen species. Against this background, the present study aimed to improve the cryotolerance and developmental competence of prepubertal calf oocytes by adding L-carnitine (LC...

Oocytes from antral follicles are dependent on adequate gene expression regulation to initiate and to undergo oocyte maturation. In vitro maturation (IVM) is an essential part of the in vitro embryo production (IVP). The quality of oocytes plays an important role in determining the production and quality of the resulting embryos, and the sexual mat...

During mammalian gametogenesis a wide epigenetic reprogramming occurs, which has an important role in embryo development after fertilization. One of the most important epigenetic events that occur during this period is the X chromosome inactivation (XCI). XCI has been largely studied in murine, but little is known in bovine. In order to better unde...

In this study we examined quality, longevity and ability of epididymal sperm (EP) to bind to oviduct explants (OE) after cooling and cryopreservation. Ejaculated (EJ) and EP sperm from seven bulls were evaluated before, during and after cryopreservation for total (TM), progressive motility (PM), sperm morphology, plasma membrane integrity (PMI) and...

Cumulus cells (CCs) have an important role during oocyte growth, competence acquisition, maturation, ovulation and fertilization. In an attempt to isolate potential biomarkers for bovine in vitro fertilization, we identified genes differentially expressed in bovine CCs from oocytes with different competence statuses, through microarray analysis. Th...

Cryopreservation of IVP embryos is affected by the concentrations high of lipid droplets that accumulate inside the blastomeres. Therefore, the partial removal of intracytoplasmic lipids by stimulating of lipolysis chemically or by decreasing the uptake or the synthesis of fatty acids by the cells, can be an alternative to improve cryopreservation...