Eduardo L. Gastal

Eduardo L. Gastal
Southern Illinois University Carbondale | SIU · Department of Animal Science, Food and Nutrition

DVM, MS, PhD; Professor, Department of Animal Science, Food and Nutrition, Southern Illinois University (SIU)

About

210
Publications
75,414
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Introduction
Dr. Gastal’s current areas of research are ovarian folliculogenesis, reproductive physiology and endocrinology, assisted reproductive technologies, and reproductive ultrasonography with the primary goal of using the mare and the cow as research experimental models for comparative studies of ovarian function, obesity and aging in women. Folliculogenesis in women has also been the focus of our studies.
Additional affiliations
November 2009 - present
Southern Illinois University Carbondale
Position
  • Professor (Full)
Description
  • Interests: Ovarian folliculogenesis, reproductive physiology and endocrinology, assisted reproductive technologies, and reproductive ultrasonography with the primary goal of using the mare as a research experimental model.

Publications

Publications (210)
Article
Full-text available
Background: In vivo studies involving molecular markers of the follicle wall associated with follicular fluid (FF) milieu are crucial for a better understanding of follicle dynamics. The inability to obtain in vivo samples of antral follicle wall (granulosa and theca cells) without jeopardizing ovarian function has restricted advancement in knowle...
Article
The inability to obtain in vivo samples of antral follicle wall layers without removing the ovaries or sacrificing the animals has limited more in-depth studies on folliculogenesis. In this study, a novel ultrasound-guided follicle wall biopsy (FWB) technique was used to obtain in vivo follicle wall layers and follicular fluid samples of growing an...
Article
During the reproductive lifespan of a female, only a limited quantity of oocytes are naturally ovulated; therefore , the mammalian ovary possesses a substantial population of preantral follicles available to be handled and explored in vitro. Hence, the manipulation of preantral follicles enclosed in ovarian tissue aims to recover a considerable pop...
Article
The mammalian ovary is responsible for essential stages of folliculogenesis and hormonal production, regulating the female physiological functions during the menstrual/estrous cycles. The mare has been considered an attractive model for comparative studies due to the striking similarities shared with women regarding in vivo and in vitro folliculoge...
Article
Ovulatory follicle development and associated oocyte maturation involve complex coordinated molecular and cellular mechanisms not yet fully understood. This study addresses the relationships among follicle diameter, follicle wall blood flow, follicular-fluid factors, and gene expression for follicle growth, steroidogenesis, angiogenesis, and apopto...
Article
Among female livestock, the mare has the shortest interval from parturition to first ovulation. Due to the scarcity of research on postpartum mares, little progress has been made on the characterization of the resumption of ovarian cyclicity after parturition. This study compared follicular and gonadotropin dynamics during follicle emergence and de...
Article
The complex composition of the follicular fluid (FF), the intimate proximity to the oocyte, and the continual changes in their composition have a major effect on folliculogenesis and oogenesis. To date, the profiling of FF proteomes during follicle selection, development, and ovulation has not been comprehensively investigated. Therefore, a shotgun...
Article
Recent in vitro follicle culture (IVFC) studies in caprine have yielded lower maturation rates using late preantral follicles compared to early antral follicles. Thus, research focusing on developing stage-specific customized culture systems able to improve the efficiency of IVFC for late preantral follicles are warranted. This study aimed to compa...
Article
Full-text available
Characterization of the ovarian preantral follicle population is a necessary step to improve understanding of folliculogenesis and ovarian physiology. Therefore, in the present study, the preantral follicle population in the equine ovary in young and old mares was investigated according to follicular morphology, follicular class, distance from the...
Cover Page
Full-text available
Mean percentage of follicle wall blood flow and follicle diameter (mm) in different diameter categories of largest/ovulatory follicle in mares. DOI: 10.1002/mrd.23549
Article
The aim of this study was to compare the dominant follicle (DF) and gonadotropin dynamics for 9 days before ovulation in postpartum lactating (PP Lactating) versus non-postpartum cycling (N-PP Cycling) mares. Every PP Lactating mare on the day of parturition was paired with a N-PP Cycling mare, and the data analyses considered the partum-ovulation...
Article
Full-text available
Back Cover Caption: The cover image is based on the Research Article Hemodynamic, endocrine, and gene expression mechanisms regulating equine ovarian follicular and cellular development by Aurea Wischral et al., https://doi.org/10.1002/mrd.23549.
Article
The hypothalamic-pituitary-gonadal (HPG) axis is the principal modulator of reproductive function. Proper control of this system relies on several hormonal pathways, which make the female reproductive components susceptible to disruption by endocrine-disrupting chemicals such as tributyltin (TBT). Here, we review the relevant research on the associ...
Article
Full-text available
Ovarian tissue transplantation methods using cooled and cryopreserved samples have been attractive options for fertility preservation in animal models and humans. The aim of this study was to evaluate the impact of previous exposure to cooling, cryopreservation, and VEGF on the overall efficiency of equine ovarian tissue after heterotopic xenotrans...
Article
This comparative study between postpartum lactating (PP Lactating) and non-postpartum cycling (N-PP Cycling) mares aimed to characterize reproductive patterns, types and frequencies of follicular waves, corpus luteum and endometrial echotexture dynamics, and the influence of season and body condition. Mares from each group were paired considering t...
Article
Ovarian tissue transplantation (OTT) is a technique well established and successfully applied in humans using mainly orthotopic or heterotopic transplantation sites. In livestock, OTT is still in its infancy and, therefore, different aspects of the technique, including the efficiency of different heterotopic OTT sites as well as the potential effec...
Article
This study evaluated the effect of adding ultra-diluted and dynamized Arnica montana 6 cH, and its vehicle (0.3% ethanol) to the in vitro maturation (IVM) medium, in the absence (experiment 1) or presence (experiment 2) of heat stress (HS), on bovine oocyte maturation and in vitro embryo production (IVEP). In experiment 1 (n = 902 cumulus oocyte co...
Article
Full-text available
Heterotopic and orthotopic ovarian tissue autotransplantation techniques, currently used in humans, will become promising alternative methods for fertility preservation in domestic and wild animals. Thus, this study describes for the first time the efficiency of a heterotopic ovarian tissue autotransplantation technique in a large livestock species...
Article
The aim of this study was to compare the embryonic and early fetal development of horse embryos between recipient mules and mares from day 10-60 of pregnancy, in addition to hormonal (eCG and progesterone), ovarian, and uterine characteristics for approximately 4 months. Embryo donor mares (n = 5) and two groups of recipients (acyclic mules, n = 7;...
Article
This study aimed to evaluate the role of anethole during the in vitro culture of caprine early antral follicles. Early antral follicles were isolated from caprine ovaries and cultured for 18 days without (control) or with anethole (300 µg/ml). After culture , the cumulus-oocyte complexes were subjected to in vitro maturation, followed by parthenoge...
Article
Oxidative stress is one of the most detrimental factors that affect oocyte developmental competence and embryo development in vitro. The impact of anethole supplementation to in vitro maturation (IVM) media on oocyte maturation and further bovine in vitro embryo production was investigated. Oocytes of slaughterhouse-derived bovine ovaries were plac...
Article
Three different sources of FSH (porcine pituitary, pFSH; recombinant bovine, rbFSH; and recombinant human, rhFSH) were compared during in vitro culture of preantral and early antral follicles of goats for 18 days. Treatments were: base medium supplemented with no FSH (control), 10, 50, or 100 mIU/mL pFSH (pFSH10, pFSH50, and pFSH100, respectively),...
Article
An appropriate implantation site favors angiogenesis and avoids ovarian tissue damage after tissue grafting. The objective of this study was to evaluate the effects of intramuscular (IM) and subcutaneous (SC) sites for ovarian grafts in goats by evaluating follicular morphology and activation, preantral follicle and stromal cell densities, tissue D...
Article
The mare, compared to other livestock, has the shortest interval from partum to the first ovulation. In monovulatory species, the follicle deviation process in a wave is characterised by the continued growth of the dominant follicle (DF) and regression of the subordinate follicle. Although follicle diameter deviation, a key event of follicle select...
Article
Cover Caption: The cover image is based on the Research Article Transition to the ovulatory season in mares: An investigation of antral follicle receptor gene expression in vivo by Ghassan M. A. Ishak et al., https://doi.org/10.1002/mrd.23277. Credit: Cover image © Eduardo L. Gastal Images.
Article
ABSTRACT This study aimed to gain insight on the effect of different seasons of the year on the expression pattern of growth factor and hormone receptors involved in follicle development. A novel follicle wall biopsy technique was used to collect in vivo follicle wall layers (i.e., granulosa, theca interna, and theca externa) and follicular fluid s...
Article
Full-text available
Abstract Background: Proteomic studies of follicular fluid (FF) exist for several species, including the horse; however, the seasonal influence on FF proteome has not been explored in livestock. The application of high-throughput proteomics of FF in horse has the potential to identify seasonal variations of proteins involved in follicle and oocyte...
Article
Oxidative stress is one of the most detrimental factors that affect oocyte developmental competence and embryo development in vitro. The impact of anethole supplementation to in vitro maturation (IVM) media on oocyte maturation and further bovine in vitro embryo production was investigated. Oocytes of slaughterhouse-derived bovine ovaries were plac...
Article
Preservation of cellular integrity and its mechanisms after ovarian tissue cryopreservation (OTC) and in vitro culture (IVC) procedures are crucial aspects for the success of preservation and recovery of female fertility. This study aimed to evaluate the effects of two cryopreservation methods (slow-freezing, SF, and vitrification, VIT) on the equi...
Conference Paper
Full-text available
In vivo studies involving molecular markers of the follicle wall associated with follicular fluid milieu are crucial for a better understanding of folliculogenesis. Several ultrasound-guided techniques have contributed to understand mammalian folliculogenesis; however, there is a need to develop an in vivo follicle wall biopsy (FWB) technique to ha...
Conference Paper
Full-text available
Recently, ovarian tissue cryopreservation (OTC) and in vitro culture (IVC) systems have been described in horses (Gastal et al. 2017; Theriogenology 97:139-147). However, information about the potential of cryopreserved-thawed equine ovarian tissue to adapt and survive after IVC is still scarce. This study aimed to evaluate the effect of two cryopr...
Article
Full-text available
Little progress has been made in understanding the molecular mechanisms involved in folliculogenesis during the transition from anestrous to the ovulatory season in mares. Previous studies have used antral follicles obtained after slaughter or ovariectomy; therefore, the experimental designs were usually limited and/or compromised by the lack of fo...
Article
Full-text available
Comprehensive studies on spatial distribution of preantral follicles in the ovary are scarce. Considering that preantral follicles represent the main ovarian reserve, harvesting of these follicles is crucial for the development/use of assisted reproductive techniques. Therefore, knowledge on follicle spatial distribution can be helpful for targetin...
Article
The present study aimed to investigate a concentration-response curve of human recombinant FSH (hrFSH) for in vitro culture of isolated preantral and early antral follicles of goats. Isolated follicles were cultured for 18 days using the following treatments: basic culture medium (control); or control medium supplemented with 10, 50, and 100 mIU/mL...
Article
In countries such as Brazil and Argentina where the equine embryo transfer technique has become widespread, shortages in recipient mares are a real problem. Therefore, one alternative might be to use mules as recipients for equine embryos. The aim of this study was to compare the embryonic and early fetal development of horse embryos between recipi...
Article
Comprehensive studies on spatial distribution of preantral follicles in the ovary are scarce. Considering that preantral follicles represent the main ovarian reserve, harvesting of these follicles is crucial for the development/use of assisted reproductive techniques. Therefore, knowledge on follicle spatial distribution can be helpful for targetin...
Article
Full-text available
Primordial follicles, the main source of oocytes in the ovary, are essential for the maintenance of fertility throughout the reproductive lifespan. To the best of our knowledge, there are no reports describing the effect of anethole on this important ovarian follicle population. The aim of the study was to investigate the effect of different anetho...
Article
Study question: Do growth patterns and endocrine profiles differ between ovulatory follicles (OvFs) and luteinized unruptured follicles (LUFs) in women? Summary answer: Growth rates, diameters and associated endocrine profiles differed between OvFs and LUFs in unstimulated cycles. What is known already: Two-three waves of antral follicles deve...
Thesis
Full-text available
Brazil is one of the countries with the largest number of equine embryo transfers in the world, but recipients mares are scarce and expensive. One alternative is to use acyclic mules as recipients for equine embryos. The aim of this study was to compare for the first time the embryonic and early fetal development in recipient mules and mares from d...
Article
Full-text available
Royal jelly (RJ) was supplemented to goat oocyte in vitro maturation (IVM) medium at three different concentrations (2.5, 5, and 10 mg/ml). Maturation rate, embryo cleavage, and blastocyst rate were recorded. Gene expression of apoptosis-related transcripts was investigated in matured oocytes. Percentage of oocytes that reached MII-stage was increa...
Article
In horses, pregnancy is characterized by high levels of maternal estrogens that are produced largely by the interstitial tissue inside the gonads of the offspring, associated with a physiological gonadal hyperplasia, that is uncommon in other species. However, a detailed structural-functional understanding of the early stages of gonadal development...
Article
Biopsy pick-up (BPU) has been considered a safe method to harvest ovarian fragments from live animals. However, no studies have been reported on the use of BPU to collect in vivo ovarian tissue in goats. The goals of this study were: (i) to test different biopsy needle sizes to collect ovarian tissue in situ using the BPU method (Experiment 1), and...
Article
Color Doppler ultrasonography was used to study the temporal relationships between pre-ovulatory follicle (POF) and corpus luteum (CL) diameter and blood flow, with systemic progesterone (P4) concentration during two transitional ovulatory seasons in mares. Variables of POF and CL/P4 were evaluated for 6days before and 17days after ovulation, respe...
Article
The effect of different concentrations of alpha lipoic acid (ALA) on the development and morphology of preantral follicles, as well as the proliferative activity of granulosa cells, was assessed after short-term culture. Ovaries (n = 5) of five seasonal anestrous mares were harvested in a local abattoir. At the laboratory, nine ovarian fragments (5...
Conference Paper
Full-text available
Preservation of germ cells and gametes is crucial to protect the genetic diversity of endangered vertebrates. However, the challenges in establishing cryopreservation procedures for ovarian tissue from different species involve the complexity of the gonadal tissue structure, cell heterogeneity, and the lack of basic cryobiological and developmental...
Article
Full-text available
The knowledge about ovarian reserve is essential to determine the reproductive potential and to improve the methods of fertility control for overpopulated species, such as whitetailed deer (Odocoileus virginianus). The goal of this study was to evaluate the effect of age on the female reproductive tract of white-tailed deer, focusing on ovarian fea...
Article
A more precise characterization of the effects of hCG treatment on the preovulatory follicle is needed to improve reproductive efficiency in broodmare management. The objectives of this study were: (1) to study the effects of different hCG doses within and among three consecutive estrous cycles on ovulatory response, preovulatory follicle dynamics...
Article
Ovarian tissue cryopreservation allows the preservation of the female fertility potential for an undetermined period. The objectives of this study were to compare the efficiency of cryoprotective agents (CPAs; dimethyl sulfoxide, DMSO; ethylene glycol, EG; and propylene glycol, PROH) using slow-freezing and vitrification methods, and evaluate the v...
Article
The objective of this study was to determine whether: (1) systemic and intrafollicular cortisol concentrations in horses are directly related and (2) supraphysiologic levels of glucocorticoids affect in vitro maturation (IVM) rates of oocytes. Specifically, we studied the (1) changes in the intrafollicular cortisol and progesterone in context with...
Article
The effects of epidermal growth factor (EGF) concentrations (0, 10, 50, and 100 ng/ml) on in vitro culture (IVC) of equine preantral follicles were evaluated using histology, estradiol and reactive oxygen species (ROS) production and metabolomics. After IVC, the percentage of normal follicles was lower (P < 0.05) for all treatments when compared to...
Article
The effect of FSH supplementation on an enriched cultured medium containing insulin (10 ng/mL) and EGF (50 ng/mL) was investigated on in vitro culture of equine ovarian biopsy tissue. Ovarian tissue fragments were collected from mares (n = 10) and distributed in the following treatments: noncultured control, cultured control, and cultured + FSH. Bo...
Article
The method of transportation and the conditions imposed on the ovarian tissue are pivotal aspects for the success of ovarian tissue cryopreservation (OTC). The aim of this study was to evaluate the effect of the size of the ovarian tissue (e.g., whole ovary, biopsy size, and transplant size) during different times of storage (0, 6, 12, and 24 h) on...
Article
Full-text available
The neural system is one of the earliest systems to develop and the last to be fully developed after birth. This study presents a detailed description of organogenesis of the central nervous system (CNS) at equine embryonic/fetal development between 19 and 115 days of pregnancy. The expression of two important biomarkers in the main structure of th...
Conference Paper
Full-text available
Equine assisted reproductive technologies (e.g., superovulation and in vitro fertilization) have limited efficiency when compared with other species (bovine, ovine, human). Therefore, in vitro culture (IVC) of preantral follicles (PAF) has emerged as a future source of meiotically competent oocytes. Recently, reports have shown a positive effect of...
Article
Full-text available
Shortages in recipient mares are a real problem in countries where the equine embryo transfer technique has become very common. The objectives of this study were to compare pregnancy rates between acyclic mules and cyclic mares used as recipients for embryo transfer, and evaluate the number of embryo transfer attempts to achieve a pregnancy. This s...
Article
Full-text available
The exposure effect of cryoprotectant agents (CPAs) on morphology of preantral follicles (PAFs), stromal cell and preantral follicle densities, and area of equine ovarian fragments were evaluated. Three independent experiments with identical methodologies were performed. Each experiment was composed of one cryoprotectant agent (dimethyl sulfoxide –...
Article
Full-text available
The aim of the present study in beef cattle was to investigate potential differences in follicle size and follicle wall-blood flow between cows and heifers and to compare follicle wall-blood flow between smaller and larger follicles. Cows and heifers were treated with a synchronization protocol and follicles and CLs were measured and evaluated for...