Follicular Dynamics Research Articles

Active immunization against GnRH as an alternative therapeutic approach for the management of Bos indicus oocyte donors diagnosed with chronic cystic ovarian disease

The aim of this study was to evaluate the effect of active immunization against GnRH in Nelore (Bos indicus) cows repeatedly used as oocyte donors that developed chronic cystic ovarian disease (COD). In the first experiment, ovarian and uterine features were first compared between COD cows (n = 15) and healthy cows (n = 22, cycling control group) from the same breed and herd. Cows with COD had a greater number of large (P < 0.0001) and medium follicles (P < 0.01) but lesser small follicles (P < 0.05) than cycling controls. Mucometra was diagnosed in 73.3% of COD cows, but in none of the controls. No difference in average thickness of the endometrium was detected between groups; however, endometrial thickness and mucometra score were negatively correlated (R = −0.73, P = 0.0029) in COD cows. In the second experiment, COD cows were randomly allocated into two experimental groups, which received two 1.0 mL SC injections of either an anti-GnRH vaccine (COD immunized group, n = 8) or saline (COD control group, n = 7), given 28 days apart. Cows were examined weekly by transrectal ultrasonography during nine consecutive weeks after the first injection to evaluate the number and distribution of follicles among size classes, endometrial thickness, and presence of clinical mucometra. Vaccination against GnRH resulted in a progressive suppression of follicle growth and a reduction in the average size of the largest follicle, as well as in the number of large follicles (P < 0.01) in COD immunized cows compared with COD controls from week 7 onwards. Conversely, the number of small follicles in the COD immunized group increased after week 5 and was greater (P = 0.0023) than controls on week 9. Endometrial thickness and mucometra score were not affected (P > 0.05) by immunization against GnRH. In the third experiment, the COD immunized cows with effective suppression of follicle growth four weeks after the 2nd injection (n = 6) were submitted to three consecutive ovum pick-up (OPU) sessions (weeks 10, 11, and 12) for in vitro embryo production (IVEP). Cumulus-oocyte complexes (COC) collected from slaughterhouse ovaries were used as controls for IVEP. COD cows with produced 25.0 ± 3.8 COC per OPU session with no apparent detrimental effect of anti-GnRH vaccine on oocyte developmental potential in vitro, i.e., we observed similar cleavage rate (P = 0.5914) and greater blastocyst rate (P = 0.0177) in immunized cows compared with COC from slaughterhouse controls. Finally, in the fourth experiment wave emergence and follicular dynamics after follicle ablation were compared between COD immunized cows with effective suppression of follicle growth and a subset (n = 6) of the cycling, control group. No follicles grew beyond 4 mm diameter after follicle ablation in the COD immunized group, whereas a normal follicular wave emergence occurred in cycling controls. Antral follicle count was similar between cycling controls and COD immunized groups at 24 h and 96 h post-follicle ablation (P > 0.05), but greater in cycling controls at 48 h and 72 h post-follicle ablation (P < 0.05). In summary, our results suggest that active immunization against GnRH is effective to induce the regression of follicular cysts as well as increase the number of small follicles growing on the ovaries, in oocyte donors diagnosed with chronic COD, with no apparent negative effect on oocyte developmental potential in vitro.

Hormonal Levels and Follicular Dynamics in Relation to the Oestrous Cycle in Barb and Arabian Mares, Algeria

Abstract This current study is an effort to understand the hormonal and follicular growth in the Barb and Arabian mares during the oestrous cycle; as mares are unique creatures. A total of 53 mares with 97 oestrous cycles were studied. The mares with a mean age of 10.38 ± 4.55 were examined by ultrasonography every day during their breeding season (2017). Two blood samples from each mare (n = 24) were obtained for progesterone (P4), oestrogen (oestradiol-17 beta) and follicle-stimulating hormone (FSH) determinations. The data revealed that the duration of the oestrous cycle was between 19 to 22 days. The pre-ovulatory follicle grew (3.02 ± 1.04) millimetre per day. The rate of cycles exploited in the mare (Arabian versus Barb) for conception was significantly different (P &lt; 0.001). The maximal diameter of the follicle was 50.00 millimetre. The serum progesterone levels (P &lt; 0.01) in mares were significantly higher in the luteal phase than those recorded during the time of oestrous. However, the levels of oestradiol and for FSH did not significantly change during the oestrous cycle in the mares. Determining the association between the size of the follicle and the hormone profiles were the most reliable criterion in the prediction of ovulation.

52 Ovarian Follicular Profiling of High- and Low-immunocrit Gilts on Postnatal Day 14

Abstract Colostrum intake by neonatal piglets can be measured using the immunoglobulin immunocrit assay (iCrit). Lactocrine effects occur when maternally derived, milk-borne bioactive factors are transferred to the neonatal circulation with consumption of colostrum during nursing and affect development of somatic tissues, which can have long-term consequences in adulthood. Lactocrine deficiency, indicated by low neonatal iCrit, altered uterine gene expression and reduced fecundity in adult, neonatally lactocrine-deficient gilts. Litter size in pigs is dependent on both ovarian and uterine function. It was hypothesized that lactocrine deficiency affects development of ovarian follicles in gilts. The objective was to determine the number of primordial, primary, and secondary follicles in ovaries of gilts with high (12% ± 0.5; n = 10) or low (1.9% ± 0.4; n = 10) iCrit, determined on postnatal day (PND) 1 after birth. Paired high- and low-iCrit gilts were chosen from the same litters (birth weight; 3.1 ± 0.2 lbs). On PND 14, ovaries were collected and histological sections prepared (3 sections per animal; 30–150 µm apart). Ovarian follicles in each section were staged and the number of follicles in each category were quantified and subjected to ANOVA. Total number of ovarian follicles did not differ with iCrit (P = 0.55; 1,370.6 ± 147.8 follicles per section). The proportion of primordial, primary, and secondary follicles was 89.6 ± 1.15%, 7.7 ± 0.87%, 2.7 ± 0.51%, respectively. The number of primordial (P = 0.55), primary (P = 0.64), and secondary (P = 0.93) follicles did not differ with iCrit. Results indicate that ovarian follicular development of neonatal gilts is not sensitive to immunocrit status. Although lactocrine deficiency did not influence the ovarian follicular profile at PND 14, it remains unknown whether lactocrine programming alters ovarian follicular dynamics in neonatally lactocrine-deficient adults. USDA is an equal opportunity provider and employer.

Following de novo triglyceride dynamics in ovaries of Aedes aegypti during the previtellogenic stage

Understanding the molecular and biochemical basis of egg development is a central topic in mosquito reproductive biology. Lipids are a major source of energy and building blocks for the developing ovarian follicles. Ultra-High Resolution Mass Spectrometry (UHRMS) combined with in vivo metabolic labeling of follicle lipids with deuterated water (2H2O) can provide unequivocal identification of de novo lipid species during ovarian development. In the present study, we followed de novo triglyceride (TG) dynamics during the ovarian previtellogenic (PVG) stage (2–7 days post-eclosion) of female adult Aedes aegypti. The incorporation of stable isotopes from the diet was evaluated using liquid chromatography (LC) in tandem with the high accuracy (< 0.3 ppm) and high mass resolution (over 1 M) of a 14.5 T Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (14.5 T FT-ICR MS) equipped with hexapolar detection. LC-UHRMS provides effective lipid class separation and chemical formula identification based on the isotopic fine structure. The monitoring of stable isotope incorporation into de novo incorporated TGs suggests that ovarian lipids are consumed or recycled during the PVG stage, with variable time dynamics. These results provide further evidence of the complexity of the molecular mechanism of follicular lipid dynamics during oogenesis in mosquitoes.

Supplementation of granulosa cells conditioned medium with pyruvate and testosterone could improve early follicular development in cultured 1-day-old mouse ovaries.

In vitro activation of primordial follicles could serve as a safe method to preserve fertility in patients with cancer subjected to ovarian tissue cryopreservation during oncotherapy, however the culture medium for this purpose requires to be optimized. Granulosa cell conditioned medium (GCCM) has been recognized to enhance primordial follicle activation and the present study was conducted to understand whether addition of pyruvate, a combination of insulin, transferrin and selenium (ITS) or testosterone to GCCM could improve its efficiency in this regard. To this end, 1-day-old mouse ovaries were cultured in four different media including CON (control; containing GGCM only), PYR (containing GCCM plus pyruvate), ITS (containing GCCM plus ITS) or TES (containing GCCM plus testosterone) for 11 days. Furthermore, follicular dynamics and gene expression of factors involved in follicular development were assessed using histological examination and RT-PCR, respectively, on days 5 and 11 of culture. Pyruvate decreased follicular activation, but it enhanced the progression of follicles to the primary stage. Moreover, it upregulated Bmp15 and Cx37 (P < 0.05). In the ITS group, activation of follicles was not affected and total number of follicles was reduced by day 11 of culture. Additionally, ITS downregulated Pi3k, Gdf9, Bmp15 and Cx37 (P < 0.05). Although testosterone did not affect primordial follicle activation, it enhanced the development of follicles up to the preantral stage (P < 0.05). Furthermore, testosterone inhibited the expression of Pten but stimulated the expression of Gdf9 and Cx37 (P < 0.05). In conclusion, the present study revealed that inclusion of pyruvate and testosterone into GCCM could enhance the early development of follicles in cultured 1-day-old mouse ovaries.

Early resynchronization of follicular wave emergence among Nelore cattle using injectable and intravaginal progesterone for three timed artificial inseminations

Follicular dynamics and pregnancy per AI (P/AI) of cattle submitted to resynchronization 13 d after TAI using a progesterone (P4) insert and supplementary injectable progesterone (iP4) were determined. There was synchronization of ovulation timing imposed (Day 0 = expected estrus; Experiment 1). On Day 13, animals were assigned to: control (only P4 insert; 15 cows and 13 heifers) and iP4 (P4 insert+100 mg iP4; 13 cows and 12 heifers) groups, and submitted to daily ovarian ultrasonography and blood collection (Day 13 to Day 22). In Experiment 2, 760 suckled cows and 498 heifers were submitted to a TAI on Day 0 and assigned into control and iP4 groups on Day 13. In animals with luteolysis on Day 22, there was a second TAI on Day 24, and on Day 37 were subjected to the opposite treatments as imposed in first resynchronization procedure. On Day 37, there was pregnancy diagnosis in animals with functional CL. The third TAI was performed on Day 48. Day of follicular wave emergence did not differ between groups and parities. Dominant follicles were larger in cows than heifers, and in animals of the control group on Day 24. Greater P4 concentrations were detected on Day 14 and Day 15 in the iP4-treated animals. Luteolysis occurred earlier in cows than heifers. Overall P/AI percentage as a result of second and third TAIs, regardless of parity, was greater in iP4-treated animals. In conclusion, females treated with a supplementary iP4 had a greater plasma P4 concentration and P/AI, but there was no effect of iP4 treatment on synchrony of timing of follicular wave.

Ovarian activity in crossbred Thai native does during naturally occurring foot-and-mouth disease (FMD) virus infection.

This study aimed to compare the follicular dynamics in goats during naturally infected with foot-and-mouth disease virus (FMD) subjected to induced ovulations, and after disease recovery, crossbred Thai native does were synchronized with CIDR for 14 days, and then PGF2α and PMSG were administered on the day following CIDR removal. The ovarian activity was determined by transrectal ultrasonography. Clinical signs (fever, anorexia, lameness, and foot lesion) were observed on day 12 post-estrus (day 0, day of expected estrus). The study was carried out for 2 periods: FMD outbreak (day 0-day 21) and FMD recovery (day 63-day 84). Infected does were classified into two groups: (I) does without (n = 5) and (II) does with clinical signs (n = 5). The results showed that during FMD outbreak, the number of follicles/waves and number of follicles > 5 mm in ovulatory follicle wave of group II were lower than those of group I and those of its own group after FMD recovery (P<0.05). Higher in follicular regression rate were found in group II compared to group I in the does with 3 follicular waves during FMD outbreak (P<0.05). Moreover, during FMD outbreak, the does had lower number of follicles > 5 mm and longer day of emergence and day of largest follicles in ovulatory follicle wave than of those after FMD recovery. This observation demonstrated that FMD impaired folliculogenesis in goats, and the ovarian activity could be restored about 1 month after disease recovery.

Effects of eCG and FSH in timed artificial insemination treatment regimens on estrous expression and pregnancy rates in primiparous and multiparous Bos indicus cows

Effects were evaluated in Bos indicus cows of eCG and FSH on follicular growth, estrous expression, and pregnancy per artificial insemination (P/AI) as a result of fixed-time artificial insemination (TAI). In Experiment 1, extent of timing-of-ovulation synchronization among cows was evaluated after imposing an estrogen/progesterone-based treatment regimen. At progesterone device removal (D8), cows were administered: eCG, or FSH or served as untreated Controls. In Experiment 2, percentage of cows P/AI was evaluated when the Experiment 1-treatment regimen was imposed. On D10, all cows were artificially inseminated. In Experiment 3, cows were assigned to two treatment groups (Control and eCG) on D8 to evaluate percentage of cows P/AI and estrous expression. In Experiment 1, follicular dynamics were similar among treatment groups. In Experiment 2, follicular growth was greater (P = 0.0001) with the eCG treatment. There was an interaction of treatment × parity (P = 0.007) on percentage of cows P/AI. There was a greater percentage of primiparous cows P/AI in the eCG-treated than Control and FSH-treated cows. There was a greater percentage of eCG-treated multiparous cows pregnant as a result of TAI than Control cows. There was an interaction of treatment × parity (P = 0.005) on P/AI in Experiment 3, in which the eCG effect was more pronounced in primiparous cows. Treatment with FSH, therefore, was not as effective as eCG in stimulation of follicular growth or enhancing percentage of cows pregnant as a result of TAI. Physiological effects of eCG, however, were also more evident in primiparous cows.

Factor de crecimiento ligado a la insulina en la reproducción animal

The development of female gametes production (gametogenesis) occurs in an interesting way, as its process depends of many combined factors. This review will approach these morphofunction mechanisms of the ovary and the folliculogenesis, correlating the function of Insulin-Like Growth Factors (IGFs), which will influence in the production of steroids hormones, in the maintenance follicular maturation, and still elucidate how the diet assists better in this phases. Besides that, with the new researches in animal reproduction, it is important emphasize the role and assists of Insulin-Like Growth Factors during these physiologic process, showing all its potential for a more efficient follicular dynamics in any species.

EFFECT OF TOCOPHEROL AND SELENIUM ON THE PERFORMANCE OF BUSERELIN FOR ESTRUS INDUCTION IN LATE SEASON ANESTRUS MARES (EQUUS CABALLUS)

The aim of this study was to determine the effect of tocopherol and selenium on the performance of buserelin (GnRH analogue) for estrus induction in anestrus mares. A total of 18 seasonally anestrus mares were divided into three equal groups (n=6 in each) after ovarian scanning. Mares in group A (treatment group) were treated with tocopherol and selenium intramuscularly along with daily dose of buserelin. Mares which came into heat within ten-day buserelin protocol, further injections of buserelin for those mares were stopped. Mares in group B were treated with buserelin intramuscularly only for ten days. Mares which came into heat within ten-day buserelin protocol, further injections of buserelin were stopped. Blood/serum was collected from each experimental mare kept in different groups (A-C) at days 1, 11, 12, 13 and 14. Onset of estrus signs was 83.3, 33.3 and 0% in group A, B and C, respectively, that was significant (P&lt;0.05) among groups. Follicular dynamics were 20.24±3.00, 14.59±2.24 and 10.35±0.63mm in groups A, B and C, respectively with significant (P˂0.05) difference. Change in serum E2 contents was significantly (P˂0.05) different among groups A, B and C whereas progesterone concentration showed non-significant difference among groups.

Comparison of two intravaginal progesterone-releasing devices in shortened-timed artificial insemination protocols in beef cattle

Commercially available intravaginal progesterone (P4) devices differ in shape, surface area and P4 load, which may affect the resulting pregnancy per AI (P/AI) following timed-AI (TAI). The objective of this study was to compare two intravaginal P4 devices on estrus rate, follicular dynamics and P/AI in beef cattle subjected to shortened-TAI protocols. In Expt. 1, nulliparous heifers were randomly assigned to a P4-releasing intravaginal device (PRID-Delta, 1.55 g P4) or a controlled internal drug release (CIDR, 1.38 g P4) at the initiation of a J-synch protocol. Heifers that displayed estrus 72 h following device removal were TAI, or if not in estrus given GnRH at 72 h and TAI at 90 h. In Expt. 2, nulliparous heifers and non-suckling cows were randomly assigned to either PRID or CIDR groups and either 1 or 2 mg of estradiol benzoate (EB) at initiation of a J-synch protocol. All cattle were TAI concurrent with GnRH 72 h after device removal. In Expt. 3, nulliparous heifers and suckling cows were randomly assigned to either PRID or CIDR groups and initiated a 5-d Cosynch protocol, with TAI concurrent with GnRH 72 h following device removal. In each experiment, cattle received estrus detection patches at device removal, which were then scored from 0 to 3 based on color change between initial application and TAI; 0 = unchanged, 1 = ≤50% change, 2 = >50% change, 3 = missing. Estrus was defined to have occurred when the patch was scored 2 or 3. Transrectal ultrasonography was used to determine cyclicity, diagnose pregnancy in all experiments, and the size of the ovulatory follicle in Expt. 3. In Expt. 1, the estrus rate was greater (72.0% vs. 61.0%; P = 0.04) in the PRID compared to the CIDR group. In Expt. 2, a parity by EB dose interaction (P = 0.02) was attributed to an increased estrus rate (52.8% vs. 41.4%; P = 0.05) in heifers given 1 vs. 2 mg EB. In Expt. 3, there was no difference in the ovulatory follicle diameter at device removal (P = 0.22) or TAI (P = 0.28) between P4 groups. Treatment with a PRID tended (P = 0.10) to increase the P/AI in cows compared to a CIDR (73.5% vs. 61.0%). In all experiments combined, the overall P/AI tended to increase (55.2% vs. 51.0%; P = 0.08) and P/AI in cattle exhibiting estrus increased (64.4% vs. 59.7%; P = 0.02) in cattle given a PRID compared to those given a CIDR, respectively. In summary, the type of intravaginal P4 device affected estrus response and P/AI following TAI in beef cows.

Caracterización ultrasonográfica modo-B y Doppler del cuerpo lúteo en llamas

Mode B and Doppler ultrasonography in ruminants, as a technique, has allowed establishing new concepts on the reproductive physiology of females, through the study of follicular dynamics and morphometry of the corpus lu-teum, therefore, the objective was to characterize using mode B ultrasound and Doppler the corpus luteum in recipients’ llamas. 37 llamas were used as recipients (27 for mode B and 10 Doppler ultrasound) that were syn-chronized by applying buserelin acetate 0.0096 mg, nine days later 0.048 mg of Prostaglandin F2α analog was applied, two days later the second dose of buserelin acetate in the same dose to a ovulation and subsequent for-mation of the corpus luteum, The B-mode evaluation of the morphometry consisted of observing the ecotexture, area, diameter and volume of the corpus luteum with the use of a SonoStar SS-8® ultrasound machine at 6.5 MHz frequency and 6 cm depth equipped with a transrectal linear transducer, with the same technique with a Draminski 4Vet® Doppler device, the percentage of luteal area of vascularization (% AVL) was determined. The data were subjected to a descriptive analysis, being 0.119±0.032 cm2 in area, 12.7±1.7 mm in diameter and 0.84±0.32 cm3 in volumen of CL, to determine the relationship between metric measurements the Pearson correlation was used observing a positive relationship between area/diameter of 0.6602, observing a high positive correlation between area and volume, finally, the characteristics of % AVL was 34.97 for the CLs of recipients llamas. In conclusion, the morphometric characteristics evaluated in mode B (area, diameter, and volume) have a positive correlation and the % AVL could be applied as a tool in efficient reproduc-tive management for the selection of receptors in camelids, understanding that it is one of the first reports of these characteristics in llamas. 0.7506, area/volume of 0.9289 and diameter/volume of

Synchronization with estradiol benzoate in the presence of the corpus luteum in Wagyu cows increases the number of medium follicles but does not interfere with in vitro production of embryos

Reproductive biotechnologies are emerging as an important element for livestock; however, some strategies must be modified to adapt to different breeding systems, such as the use of follicular synchronization protocols. This study aimed to evaluate follicular synchronization using estradiol benzoate (EB), in the presence of the corpus luteum (CL) from Wagyu oocyte donors in in vitro embryo production (IVEP). Rounds of IVEP were performed in heifers and cows (n=19) that were classified into three groups: G1/CL - animals with CL, G2/WCL - animals without CL, and G3/CL + EB - animals with CL that were subjected to follicular synchronization with EB at D0. The groups G1/CL and G2/WCL were considered the control and undertook the natural process of follicular dynamics. The results showed that the synchronization of the follicular wave with the application of EB in the presence of CL, presented a smaller number of small (6.05 ± 0.55) and large follicles (0.45 ± 0.15), but increased (P &lt; 0.05) the number of medium-sized follicles (16.20 ± 0.90). However, the results of ovum pick up showed that regardless of whether or not EB was applied, and regardless of the presence or absence of CL in the Wagyu donor, there was no difference among the groups (P &gt; 0.05) concerning the number of viable oocytes and the viability rate. It was concluded that follicular synchronization using EB in Wagyu oocyte donors that presented a CL, increased the number of medium-sized follicles. However, there was no improvement in the efficiency of ovum pick up, in vitro embryo production, and pregnancy rate.

ANTI-MÜLLERIAN HORMONE (AMH) AS ENDOCRINE MARKER FOR EMBRYO PRODUCTION IN SUPEROVULATED FRIESIAN COWS

The present study aimed to evaluate follicular dynamics, yield, quality and stage of embryos in superovulated Friesian cows with high and low AMH levels. A total of 10 Friesian cows synchronized with PGF2α to bring them in heat before start superovulation protocol. On Day 10 post oestrus, cows were injected with 2500 IU PMSG, then after 48h cow were injected with 3 ml PGF2α and with 5 ml GnRH on day 14. Cows were artificially inseminated twice at 12 and 24 h after GnRH. Embryos were collected after 7 days from AI. To measure AMH concentration 1 blood sample was collected at the beginning of second follicular wave according to ultrasonography. Results showed that number of antral follicles and total follicles was greater in high AMH level than in low AMH level donors. Differences in CL number of cows in high AMH level was greater than in low AMH level on flushing day. AMH concentration had a significant positive correlation with antral follicles number pre-treatment, total CL number on flushing day, and ovulation rate . The average number and recovery rate of recovered embryos from donor cows with high AMH level was greater than those recovered from cows in low AMH level. Also results indicated highly, significant, and positive correlation of AMH level with total number, recovery rate, excellent, good grade of embryos, and blastocysts, compact morulae, and morulae. In conclusion, circulating AMH concentration, as endocrine marker, is highly associated individually with superovulatory response and embryo production potential in cows.

The Addition of Chitosan to GnRH Analog Induces Ovarian Resumption and Improves Conception Rates in Buffaloes

During hot season, female buffaloes suffer from ovarian inactivity due to hormonal insufficiency. Therefore, impaired reproductive efficiency causes low productivity of female buffaloes. The present study aimed to compare the effect of chitosan and/or insulin addition to GnRH analog during modified Ovsync program on ovarian response and pregnancy establishment in postpartum anestrous buffaloes during low breeding during the summer season. This study was carried out in buffaloes (N=135) suffering from ovarian inactivity during the summer season. The animals were divided into three treated equal groups, i.e., Group (1) basic Ovsync protocol, Group (2) insulin-sync protocol, and Group (3) chitosan-sync protocol. Blood samples were analyzed for progesterone, estradiol, and insulin concentrations before and after treatment. Follicular dynamics were studied through transrectal scanning of the ovaries. The results revealed that administration of insulin to GnRH analog (G2) significantly increased the diameter of the largest follicle and improved the conception rate compared to basic Ovsync protocol (G1). The addition of chitosan to GnRH analog (G3) caused a significant increase in the estrous induction rates (86.6%), increased the size of the largest follicle (p<0.05), and improved conception rates (76.9%) compared to basic Ovsync protocol (G1). Serum progesterone concentrations increased after treatment (p<0.05) in all groups indicating the resumption of ovarian activity. In addition, serum estradiol concentration increased after treatment in G2 and G3 (p<0.05) compared to G1. Therefore, we conclude that the addition of chitosan to GnRH analog induces ovarian resumption and improves conception rates. Subsequently, chitosan-sync protocol can be used in the treatment of the great infertility problem of postpartum anestrous during summer season in buffaloes. Furthermore, this protocol avoids the repeated injection of the animal as in insulin-sync protocol, so that protect the animal from more injection pains in addition to the decreases cost and duration of treatment.

ITRAQ-based proteomic analysis of bovine pre-ovulatory plasma and follicular fluid

Bovine follicular fluid (FF) creates a unique microenvironment in follicles necessary for follicle growth, oocyte maturation, and estradiol (E2) production. The objective of this study was to analyze changes in proteins in FF and plasma (PL) from animals with high E2 (HE2) or low E2 (LE2) during the preovulatory period. Beef cows were synchronized, and follicular dynamics and ovulatory response were monitored using transrectal ultrasonography. Nine cows were selected and slaughtered, blood samples were collected at slaughter and FF was aspirated from dominant follicles (DF; >10 mm). Abundant proteins (albumin, IgG, IgA, and alpha-1-antitrypsin) were depleted from both PL and FF. Peptides were labeled with iTRAQ reagents and quantified using 2-dimentional liquid chromatography ESI-based mass spectrometry. Estradiol was associated with protein changes in PL and FF. Protein expression changes between FF HE2 and FF LE2 were greater than between PL HE2 and PL LE2. There were 15 up-regulated proteins and 10 down-regulated proteins in FF HE2 compared to FF LE2, and 7 proteins up-regulated and 9 proteins down-regulated in PL HE2 compared to PL LE2. Several of the differentially expressed proteins function in follicle development and were mainly categorized under cellular process and metabolic process. Pathway analysis identified the up- and down-regulated proteins were predominantly associated with the complement and coagulation cascades. The data demonstrate E2 regulates a wide range of reproductive associated proteins in bovine PL and FF and can provide the basis for further investigation of specific processes involved in such regulation.

Protocolo J-synch con y sin eCG en vacas Brown Swiss y sus cruzas con Bos Indicus en la amazonía ecuatoriana

La incorporación de protocolos con proestro prolongado en condiciones extremas ha permitido mejorar la concepción. Por lo tanto, el objetivo de esta investigación fue evaluar los resultados del protocolo con proestro prolongado denominado J-Synch con y sin eCG, sobre la dinámica folicular y porcentaje de preñez en vacas doble propósito en la Amazonía Ecuatoriana. El trabajo se efectuó en la provincia de Pastaza - Ecuador, desde octubre del 2018 a octubre del 2019. Se utilizaron 448 vacas multíparas en producción con cría al pie de las razas Brown Swiss y sus cruzas (Bos indicus). Se trabajó con cuatro tratamientos, las vacas fueron inseminadas artificialmente a tiempo fijo en el día nueve T1: J-Synch, eCG, Celo IATF 60 horas (n= 120); T2: J-Synch y eCG y Sin Celo+ GnRH IATF 72 horas (n=118); T3: J-Synch y Celo IATF 60 horas (n=103); T4: J-Synch más Sin Celo más GnRH más IATF 72 Horas (n=107). La tasa de preñez fue del 55% (T1), el 49% (T2), el 51% (T3) y el 50% (T4) sin mostrar diferencias significativas. El desarrollo folicular y el diámetro del cuerpo lúteo mostraron diferencias significativas (p0,05). Se concluye que los tratamientos J-Synch más eCG a las 60 horas y las 72 horas tuvieron diferente comportamiento en el desarrollo folicular y en el tamaño del cuerpo lúteo. El porcentaje de preñez no difirió entre los tratamientos, aunque existió un 44,5% más probabilidad de quedar preñada una vaca con el T1 en comparación con el T2. Además, que aumentaría un 22,5% la preñez aplicando el T1 en comparación con el T3, y se lograría un 18% mayor de preñez con el T3 si se compara con el T2.

Ovarian Follicular Dynamics, and Hormonal and Biochemical Profile in Post-Pubertal and Postpartum Jaffrabadi Buffaloes

Jaffrabadi buffalo is one of the heaviest buffalo breeds of the world (800 kg) and is known for poor reproductive efficiency. There is a scarcity of normal physiological data regarding reproductive parameters of Jaffrabadi buffalo. The primary objective of this study was to elucidate ovarian follicular dynamics, hormonal and biochemical profiles in 10 post-pubertal heifers (n=5 each of age 42±2 and 48±2 months) and five &gt;90 days postpartum lactating buffaloes. Ultrasound monitoring of ovaries of animals was done at weekly interval and all follicles with diameter less than 4 mm (small follicles), 4-8 mm (medium follicles) and greater than 8 mm (large follicles) as well as CLs identified were recorded. Blood samples were also collected soon after each USG from all animals for assay of hormonal and biochemical profiles. The findings revealed that the average number of small, medium and large follicles, total number of follicles per ovary as well as diameters of largest and subordinate follicles varied greatly among periods between three groups. The size of corpus luteum ranged from 13.7 to 21.2 mm, 13.7 to 23.9 mm and 15.3 to 22.7 mm, respectively, in Group-I, II and III. In the first week of study, significantly higher (p less than 0.05) average numbers of small follicles in Group-I and III, and medium follicles and total numbers of follicles in Group-III were observed as compared to other groups. The diameter of largest follicles and subordinate follicles were non-significantly different among all groups at all periods of the study. Plasma estrogen levels were significantly higher (p less than 0.05) in Group-I as compared to Group-III and Group-II on first and second week, however, it increased significantly (p less than 0.05) in Group-II and I on fourth week of study period. Plasma insulin concentrations were significantly (p less than 0.01) lower in buffaloes (Group-III) than in heifers (Group-I and II) throughout the study period, while plasma total cholesterol and total protein levels were higher in Group-III on 3rd to 5th weeks of study. Further, there were no significant differences in the plasma FSH, LH, progesterone and blood glucose levels in animals of three groups between periods at any of the week. The ultrasonographic and endocrine profile suggested establishment of cyclicity with silent ovulation. However, the behavioural estrus was still not manifested by these post-pubertal heifers and postpartum lactating buffaloes. These results are helpful to diagnose anovulatory conditions and/or true anestrus and initiate estrus synchronization protocols for early conception in Jaffrabadi buffaloes.

Circulating progesterone concentrations and preovulatory follicle diameters affecting ovulatory response in crossbred dairy heifers, following a 7-day progesterone-based synchronization protocol.

The present study was aimed at evaluating the differences of ovarian follicular dynamics and circulating progesterone (P4) concentrations between crossbred Holstein heifers that ovulated and did not ovulate after a P4-based synchronization protocol. Twenty-one crossbred (Holstein × Thai native) heifers with random stages of the oestrous cycle were subjected to the ovulation synchronization protocol, using an intravaginal P4-releasing device (Eazi-Breed CIDR®) for 7 days. Out of 21 CIDR-treated heifers, 14 ovulating heifers were classified as the ovulatory group and 7 non-ovulating heifers were considered the anovulatory group. The heifers having new wave emergence in ovulatory and anovulatory groups were 11/14 (78.6%) and 4/7 (57.1%), respectively. In ovulating heifers, the mean (± SEM) diameter of preovulatory follicle (PF, mm) was significantly larger, compared to non-ovulating heifers (7.21 ± 0.32 versus 4.04 ± 0.44; P = 0.001), while the mean (± SEM) follicular growth rates (mm/d) in non-ovulating heifers tended to be lower, compared to ovulating heifers (0.73 ± 0.17 versus 1.06 ± 0.08; P = 0.07). The mean (± SEM) circulating P4 concentration (ng/ml) throughout the CIDR protocol (0-10 days) in non-ovulating heifers was significantly higher, in comparison with ovulating heifers (2.82 ± 0.27 versus 1.83 ± 0.16; P = 0.02). However, no significant difference in the mean corpus luteum volume between groups was observed. In conclusion, the present results suggested that elevated circulating P4 concentrations and smaller PF diameters could cause ovulation failure in crossbred Holstein heifers, following a 7-day CIDR-based synchronization protocol.

Gestational exposure to Δ9-THC impacts ovarian follicular dynamics and angiogenesis in adulthood in Wistar rats

With the legalization of marijuana (Cannabis sativa) and increasing use during pregnancy, it is important to understand its impact on exposed offspring. Specifically, the effects of Δ-9-tetrahydrocannabinol (Δ9-THC), the major psychoactive component of cannabis, on fetal ovarian development and long-term reproductive health are not fully understood. The aim of this study was to assess the effect of prenatal exposure to Δ9-THC on ovarian health in adult rat offspring. At 6 months of age, Δ9-THC-exposed offspring had accelerated folliculogenesis with apparent follicular development arrest, but no persistent effects on circulating steroid levels. Ovaries from Δ9-THC-exposed offspring had reduced blood vessel density in association with decreased expression of the pro-angiogenic factor VEGF and its receptor VEGFR-2, as well as an increase in the anti-angiogenic factor thrombospondin 1 (TSP-1). Collectively, these data suggest that exposure to Δ9-THC during pregnancy alters follicular dynamics during postnatal life, which may have long-lasting detrimental effects on female reproductive health.