Serum Progesterone Concentrations Research Articles

Dietary supplementation with thyme oil improves the reproductive characteristics of Barki adult and prepubertal ewes

The reproductive technology has a significant impact on the development of livestock production. The thyme oil, rich in phytoestrogen chemicals like apigenin, has been found to enhance reproductive performance by mimicking estrogen’s action. This study aimed to investigate the effects of oral supplementation with thyme essential oil on the reproductive organ biometry, and reproductive performance in adult and prepubertal Barki ewes. Seventy ewes were treated with intravaginal sponges impregnated with 40 mg. medroxyprogesterone acetate for 14 days and simultaneously assigned randomly to two groups (20 adult and 15 prepubertal ewes per group), i.e., a control and a thyme oil treated (2.25 mg/kg body weight) group. The number of follicles, follicle diameter, corpora lutea diameter, and estrogen concentration were higher in the thyme oil-treated group than in the control group without comparing between adult ewes and prepubertal ewes. Additionally, the number and diameter of the large follicles were higher (P < 0.05) in the right-side ovary of adult ewes compared with that in prepubertal ewes at day 15. Moreover, thyme oil treatment resulted in higher conception (P < 0.01), lambing rates (P < 0.05), and fecundity (P < 0.01), with values 95.12, 136.73, and 130.25 compared with those in the control group, with values 63.51, 105.24, and 66.97, respectively, without comparing between adult ewes and prepubertal ewes. The adult ewes had a stronger estrus response and better fertility measurement values than prepubertal ewes. Additionally, the estrogen serum levels were positively correlated with the number (P < 0.05) and diameter (P < 0.01) of follicles, and the progesterone serum concentration was positively correlated with the corpora lutea diameter (P < 0.01), without treated group. In conclusion, dietary supplementation with thyme oil improved the follicular population and reproductive performance, which has a good effect on the adult and prepubertal ewes in the Barki ewes.

Fertility and early embryonic development in a CD46-edited Gir heifer with reduced susceptibility to BVDV.

Bovine viral diarrhea virus (BVDV) infection during pregnancy is a significant contributor to reproductive failures in cattle. The bovine receptor for BVDV (CD46) was previously edited with a six amino acid substitution (G82QVLAL to A82LPTFS) and shown to have significantly reduced BVDV susceptibility in a Gir heifer calf. Since a role for CD46 has been proposed in mammalian fertilization, our objective was to assess the edited heifer's fertilization rates, early embryonic development, and germline transmission conformation of the edit. Cumulus oocyte complexes were collected from the edited heifer and unedited females, fertilized with semen from an unedited bull and cultured until the blastocyst stage. Ultrasound examinations and serum progesterone concentration were also monitored to confirm estrous cyclicity in the CD46-edited heifer. Estrous cyclicity was normal with visualization of a corpus luteum and elevated progesterone concentrations. Fertilization rates and blastocyst development were not different in oocytes from edited and unedited controls. Genome sequence analysis of blastocysts confirmed germline transmission of either edited allele from the heifer. Subsequently, the CD46-edited heifer was artificially inseminated with semen from an unedited Gir bull and fertility status was confirmed with a diagnosed conception at day 35 of gestation. Thus, a six amino acid substitution in CD46 did not negatively affect fertilization of edited oocytes or early embryonic development when fertilized with semen from an unedited bull. An edited bull is still needed to similarly evaluate reproductive function of sperm cells carrying this CD46 edit.

Progesterone peak influences embryonic developmental morphokinetics on trigger day? A retrospective study

ObjectivePremature Progesterone Rise (PPR) is characterized by elevated serum progesterone concentrations either towards the end of the follicular phase or on the trigger day, surpassing a pre-defined threshold value. Aim of the study is to evaluate the impact of PPR exceeding 1.5 ng/ml at the time of hCG-trigger on embryo morphokinetic parameters and to identify predictive biomarkers of in IntraCytoplasmic Sperm Injection (ICSI) cycles outcomes.MethodsIt is a retrospective study including patients underwent ICSI cycles in the period 2020–2023. 58 patients were recruited in the study group showing P levels in the trigger day greater than or equal to 1.5 ng/ml. A matching control group of 58 patients with P levels below 1.5 ng/ml was after selected. The general characteristics of these patients, including age, Body Mass Index (BMI), antral follicle count (AFC), anti-Müllerian hormone (AMH) and follicle-stimulating hormone (FSH) levels, the type of infertility and smoking/non-smoking patients, were recorded on the day of their initial visit. Subsequently, data were collected regarding the number of eggs retrieved, mature eggs, successfully fertilized eggs, and embryos reaching the blastocyst stage. Additionally, the timing of embryonic development and the quality of obtained blastocysts, as assessed by the degree of expansion and the characteristics of the inner cell mass (ICM) and trophectoderm (TE), were evaluated using Time-Lapse technology.ResultsElevated P levels exceeding 1.5 ng/ml on the trigger day were directly associated with a significantly larger number of antral follicles, consequently leading to a higher count of retrieved eggs, mature eggs, successfully fertilized eggs and embryos reaching the blastocyst stage. Furthermore, the analysis of morphokinetic parameters indicated faster division times and a notably greater number of high-grade blastocysts in the study group compared to the control group.ConclusionsP levels ≥ 1.5 ng/ml on the trigger day did not negatively impact embryonic morphokinetic parameters, instead resulting in faster embryo development in the initial stages.

Maternal-Fetal Blood Flow and Progesterone Concentration in Ewes Sheared at Mid or Late-Pregnancy.

These studies aimed to determine if shearing ewes at the second or last third of gestation modify the uterine and placentome blood flow, placentome size, and maternal progesterone concentration. Pregnant ewes were assigned to four groups of 12 ewes each according to the gestation period: mid-pregnancy sheared (on day 90 of pregnancy) or unshorn group; and late-pregnancy sheared group (on day 121 of pregnancy) or unshorn group. In both experimental periods, using spectral Doppler ultrasonography, placentomes and uterine artery blood flow and placentome size were evaluated 14 days before and 6 days after shearing. An additional measurement was performed 26 days after shearing in mid-pregnant ewes. Serum progesterone concentration was measured before shearing 4, 24, 72 h, and 22 days after shearing. The uterine artery's end-diastolic velocity (EDV) tended to be greater in the sheared than in the non-sheared ewes (p = 0.1). Peak systolic velocity (PSV) and EDV of placentome increased (p = 0.05 and p = 0.008, respectively) on day 26, accompanied by an increase in placentome area (p = 0.035) in mid-pregnant ewes. In late-pregnant ewes, uterine artery and placentome blood flow and size did not vary. Progesterone concentration varied with time but was not affected by shearing. In conclusion, shearing triggered an increase in placentome size and some changes in blood flow only when ewes were sheared during the second third of their pregnancy. Shearing ewes either the second or last third of gestation did not affect uterine artery blood flow and progesterone secretion.

Evaluation of a non-radioactive rapid test for the determination of serum progesterone in the mare

The determination of progesterone from mares’ serum plays a decisive role in diagnosing estrus cycle disorders or luteal insufficiency. To date, no measurement methods are available for rapid quantitative diagnosis of serum progesterone in the mare that would allow results to be available within a two-hour time frame. The present study will evaluate a commercial enzyme-linked fluorescent assay, the mini VIDAS device (bioMérieux, Nürtingen, Germany). Serum was prepared from the blood samples of one hundred and seven mares, divided into two aliquots, and stored at –20°C. Subsequently, comparative progesterone measurements were carried out using radioimmunoassay (RIA) and mini VIDAS, with RIA as the reference standard. The results show a strong positive correlation between the two measurement methods (Spearman rank correlation rs = 0.96381 (p < 0.05). The tests confirm that the mini VIDAS can be used for equine serum progesterone concentration determination and provides reliable results in less than an hour. For accurate estrus cycle diagnostics, high precision in the low measurement range is essential, as even minor deviations can result in ovulation misdiagnosis. Despite the high correlation of the measuring methods, deviations from the reference method can be observed in the low measuring range of the mini VIDAS, which suggests potential limitations of this study.

Increased expression of Interferon-stimulated gene 15 (ISG15) in cervical cells on day 14 of pregnancy in Holstein heifers

In cattle, expression of interferon (IFN)-stimulated genes in the female reproductive tract has been reported as an early pregnancy diagnostic tool, as early as d 17 of pregnancy. The hypothesis of this study was that expression of ISG15 in the cervix of pregnant heifers is increased on d 14 of pregnancy. The objective was to compare the expression of ISG15 in cervical cells between pregnant and cyclic heifers (control, sham-inseminated) on d 14, 16, and 18 after insemination (d 0; D0). Holstein heifers were submitted to an estrus synchronization protocol and inseminated with extender only (“control,” n = 6), or with regular semen (n = 15). Heifers were classified as pregnant (n = 10) by ultrasound at D30 through the detection of a viable embryo with a heartbeat. Blood samples from the coccygeal vein were collected to determine serum progesterone concentrations on D14, D16, and D18. The expression of ISG15 and PGR in cervical cells collected through cytobrush was measured on D14, D16, and D18. A receiver operating characteristic (ROC) curve was calculated to quantify the pregnancy diagnostic accuracy of ISG15 and PGR expression. The expression levels of ISG15 in cervical cells were significantly greater in pregnant compared with control heifers on D14, and remained greater on D16 and D18, while differences in PGR were observed only on D18. Scatter plots and ROC analyses showed the most accurate prediction of pregnancy for ISG15 on D16. In conclusion, cervical cells express greater ISG15 mRNA in pregnant vs control heifers as early as D14 post-insemination, with the best accuracy on D16.

Regulator of G-Protein Signaling 2 Knockout in CD4+ T Cells Promotes Anti-Inflammatory T Cells, Enhancing Ovulation, and Oocyte Yield.

To determine the downstream effects on ovarian function and immune cell differentiation in the ovary and uterus using a model in which RGS2 was knocked out specifically in CD4+ T cells. Laboratory based experiments with female mice. Female congenic (fully backcrossed) and non-congenic (mixed strain) mice with CD4 T cell-specific RGS2 knockout. Four-week-old female CD4 RGS2 knockout (CD4 RGS2 KO ) mice and their littermate controls (CD4 RGS2 CTL ) were subjected to superovulation using pregnant mare serum gonadotropins. Oocyte numbers, lymphocyte populations in the ovary and uterus, and serum estradiol and progesterone concentrations. In non-congenic (mixed strain) mice, CD4 RGS2 knockout (KO) promoted higher oocyte ovulation and increased uterine total leukocyte numbers. Similarly, congenic (fully backcrossed strain) mice showed higher oocyte numbers and increased uterine total leukocytes in the CD4 RGS2 KO mice compared to CD4 RGS2 CTL mice. Pro-inflammatory CD4+ T helper (T H ) 1 and T H 17 cell frequencies in the ovary and uterus were unchanged, while Treg and T H 2 cell frequencies were elevated, along with increased concentrations of estradiol and progesterone in the serum of CD4 RGS2 KO mice. Our study highlights the important role of RGS2 in CD4+ T cells within the context of reproduction. The dysregulation of immune responses due to RGS2 knockout in CD4+ T cells appears to enhance oocyte production. Further research is warranted to elucidate the precise mechanisms by which RGS2 influences reproductive outcomes, including its impact on fecundability, endometrial receptivity, and successful implantation.

7951 The Response of HPT Axis &amp; BAT to Cold Exposure Is Delayed in Female Rats Compared to Males

Abstract Disclosure: A. Gutiérrez-Mata: None. L. Jaimes-Hoy: None. I. Sotelo-Rivera: None. F. Romero-Arteaga: None. R.M. Uribe: None. J.L. Charli: None. P. Joseph-Bravo: None. Cold exposure activates the sympathetic nervous system releasing NE in thermogenic brown adipose tissue (BAT) and in parallel, the Hypothalamus-Pituitary-Thyroid (HPT) axis, increasing synthesis and release of hypothalamic-TRH, pituitary-TSH, and thyroid hormones T4 and T3; T4 in concert with NE induce brown adipose tissue (BAT) thermogenesis through stimulation of deiodinase 2 (Dio2), and uncoupling protein 1 (Ucp1) expression. These changes are detected within the first hour in male rats [J Neuroendo 12:861, 2014] while in females, only in ovariectomized [J Neuroendocrinol 21:439, 2009]. Given the thermogenic effect of ovarian hormones, we hypothesized that females could respond to longer exposures. Female Wistar rats were exposed individually to 5°C for 1 to 5h and compared to male’s acute response (15 min to 4h); controls were moved individually to a nearby room at 22°C for similar times. Rats were euthanized by guillotine, rectal temperature was immediately measured, trunk blood collected, serum separated, and tissues kept at -70°C. Hormone concentrations were quantified in serum by RIA and ELISA, and gene expression in paraventricular nucleus (PVN), anterior pituitary (AP), and BAT by RT-PCR or qPCR. Body temperature of cold-exposed males was higher than isolated controls since the first 30min, Trh expression increased at 1h in the paraventricular nucleus (PVN), TSH release from 15 min up to 2 hours, T4 levels peaked until 4h, and T3 increased after 2h as in [Endocrinology 58:140, 1993]; Trhr1 in AP reached its lowest levels at 2h. In BAT, Dio2 expression peaked at 1h and subsequently decreased. Ucp1 increased from 30 min and remained elevated until 4h, Adrb3, and Ppargc1a expressions were highest at 4h. Cold exposure in females decreased body temperature after 4 hours when Trh PVN expression increased and that of TRH receptor 1 (Trhr1) in AP was lowest; TRH degrading enzyme (Trhde) expression peaked after 2h of cold and subsequently decreased at 4h. TSH in serum increased at 2h and then returned to control levels, T4 slightly increased at 3h, and T3 peaked at 5h. Progesterone serum concentration increased from 2h and peaked at 4h. No changes were found in estradiol serum concentration. In BAT, Dio2 expression increased from 2 to 4h, Ucp1 at 3 and 5h while that of β3 adrenergic receptor (Adrb3) decreased at 2h but rose reaching a peak at 4h. In contrast, expression of Pgc1α -the major transcriptional coactivator of Ucp1- rapidly increased (1h) decreasing afterward. The data suggest that when the ambient temperature decreases, the sympathetic system is activated including stimulation of progesterone, and supports a delayed response of female HPT axis to cold exposure, compared to male’s leading to the proposal that when female body temperature diminishes, the HPT axis and thyroid hormone-induced thermogenesis are activated.Funding: DGAPA IN217422, PAEP, CONAHCYT 790605. Presentation: 6/2/2024

Influence of menstrual cycle and oral contraceptive phases on strength performance, neuromuscular fatigue, and perceived exertion.

The primary aim of the study was to assess differences in strength performance, neuromuscular fatigue, and perceived exertion across phases of the menstrual cycle [MC; early follicular (eFP), late follicular (lFP), and mid-luteal phase (mLP)] and oral contraceptives [OCs; active pill phase (aPP) and nonactive pill phase (nPP)]. The secondary aim was to analyze the influence of fluctuating serum 17β-estradiol and progesterone concentrations on these parameters in naturally menstruating women. Thirty-four women (21 with a natural MC and 13 using OCs) completed three or two experimental sessions, respectively. Mean propulsive velocity (MPVmean) and total number of repetitions (REPtotal) were assessed during a power [3 × 8 at 60% 1RM (one-repetition maximum)] and hypertrophy squat loading (3 sets to failure at 70% 1RM), respectively. Changes in bench press and squat MPV at 60% 1RM in response to the loadings were used as surrogates for nonlocal and local fatigue, respectively. Total blood lactate accumulation (BLAA) and markers of perceived exertion were assessed in each session. No significant differences between any of the MC or OC phases were observed for MPVmean, REPtotal, nonlocal and local fatigue, and markers of perceived exertion (all P > 0.050). A higher intraindividual 17β-estradiol concentration was significantly associated with a lower MPVmean (P = 0.019). BLAA was significantly higher in the lFP than in the mLP (P = 0.019) and negatively associated with the intraindividual progesterone concentration (P = 0.005). Although 17β-estradiol may negatively influence the MPV, it appears that fluctuations of both sex hormones across the MC and OC phases are not prominent enough to induce significant or practically relevant changes in the assessed parameters.NEW & NOTEWORTHY Although a high intraindividual 17β-estradiol concentration was associated with a lower movement velocity, markers of strength performance and surrogates for nonlocal and local fatigue remained unaffected by MC and OC phases. Blood lactate accumulation was significantly reduced in the mLP. Furthermore, our findings suggest that the impact of the MC phases varies greatly among individuals. Individuals with high fluctuations in sex hormone concentrations may experience relevant changes in the assessed parameters.

Serum Progesterone Level on the Day of Embryo Transfer and Clinical Pregnancy Rate in Patients Undergoing Down-Regulated Frozen Embryo Transfer Cycles; Prospective Observational Study

Abstract Background Serum Progesterone concentration &amp;lt;5 ng/ml on the day of frozen embryo transfer (FET) is associated with significantly decreased pregnancy and live birth rates. Aim of the Work This study aims at finding the critical cutoff value of serum progesterone on day of FET that significantly affects pregnancy rates. Patients and Methods The current study was conducted at Ain Shams University Maternity Hospital- IVF Unit during the period between April 2022 and December 2022. It included a total number of 108 patients who either were assessed for eligibility of the study, of which, 14 were excluded due to non-matching inclusion criteria or had exclusion criteria. 4 patients did not consent to participate in the study and 86 patients matched. They were preaped for frozen emberyo transfer according to IVF unit protocol at Ain Shams university and serum progesterone level on day of emberyo transfer was assessed and matched to clinical pregnancy rate. Results Progesterone on day of embryo transfer was significantly lower in cases with positive chemical pregnancy with a cut off value ≤39.2 ng/mL. Conclusion Progesterone is essential for establishing and maintaining embryo implantation and pregnancy; also, P4 is used for luteal phase deficiency in infertility treatment. Yet, progesterone therapy’s optimal timing and dose can influence the impact of P4 on pregnancy. Also, low or elevated P4 level can negatively impact embryo transfer timing and pregnancy rate. This study demonstrated that age, BMI and progesterone on day of embryo transfer had significant low diagnostic performance in predicting positive chemical pregnancy This study illustrated that no statistical significant difference according to chemical pregnancy regarding hormonal profile Before the start of estradiol valerate. Progesterone on day of embryo transfer was significantly lower in cases with positive chemical pregnancy.

Effect of post-mating administration of ketoprofen on serum progesterone concentration and fertility in Akkaraman ewes.

A major cause of early embryonic losses is inadequate secretion of progesterone (P4) hormone due to luteal insufficiency in farm animals. Post-mating applications that directly or indirectly increasing serum P4 concentrations have a positive effect on fertility. The aim of this study was to investigate the effect of post-mating administration of ketoprofen on serum P4 concentration and fertility in Akkaraman ewes synchronized with a short-term protocol during the breeding season. Oestrus monitoring ewes after synchronization were hand-mated and randomly assigned to two equal groups (Ketoprofen vs. Control). Ewes in the ketoprofen group (KPG) (n = 40) were administered with ketoprofen (Rifen, Richter pharma, Austria) intramuscularly (im) at a dose of 3mg/kg on days 9 and 10 after mating. In the control group (CG) ewes (n = 40) were administered with saline im on the same days. Blood samples were collected from ewes in both groups at four different time points of post-mating days (9, 12, 15 and 18 days). The results showed that there were no statistical differences between the KPG and CG groups on fertility parameters; pregnancy rates (85% vs. 72.5%), lambing rates (100% vs. 100%), single birth rates (55.9% vs. 55.2%), multiple birth rates (44.1% vs. 44.8%), litter sizes (1.56 vs. 1.55). In pregnant ewes, serum P4 concentrations on day 18 (4.35 ± 0.34 ng/mL) in the KPG group were higher than (3.27 ± 0.27 ng/mL) in CG group (P < 0.05). It was concluded that post-mating ketoprofen administration have no significant effect on fertility, but significantly increased the serum P4 concentration on day 18 in pregnant ewes.

Treating anoestrous and delayed pubertal Achai dairy cattle with Ferula jaeschkeana

Ferula Jaeschkeana is renowned for its application in human reproductive disorders and its estrogenic effects observed in laboratory animals. This study aimed to investigate the reproductive implications of Ferula Jaeschkeana (FJ) on animals exhibiting anestrus and delayed pubertal reproductive disorders. The experiment involved 24 Achai dairy cows divided into four groups based on different doses of Ferula Jaeschkeana i) FJ-0, serving as the control group; ii) FJ-30 receiving 30 g; iii) FJ-50 receiving 50 g; and iv) FJ-70 receiving 70 g of the product. The herb, prepared as a shade-dried powder, was administered orally to the animals as a bolus along with their regular feed. Consequently, 33.34% animals from the delayed pubertal heifer group and 75% from the anestrus multiparous animal group (54.16% of entire treated animals) displayed behavioral estrus manifestations such as restlessness, bellowing, and mounting. Physical changes, including vulvar swelling and mucus discharge, were observed in these animals. Additionally, a small percentage 8.33% of animals in the delayed pubertal heifer group and 58.33% of animals from the anestrus multiparous animal group attained pregnancy, as confirmed on day 90 post-breeding. Furthermore, a significant elevation in serum estradiol levels and a reduction in serum progesterone concentrations were noted in FJ-50 and FJ-70 groups compared to the control (FJ-0) and the FJ-30 group. Thus, it can be concluded from this study that administering 50 grams of Ferula Jaeschkeana herb roots or extract to anestrous and delayed pubertal Achai cows may induce hormonal alterations, promote behavioral estrus, and facilitate conception in this breed of cattle.

Ameliorative Effect of Lycopene on Follicular Reserve Depletion, Oxidative Damage, Apoptosis Rate, and Hormonal Profile during Repeated Superovulations in Mice.

Superovulation is a crucial step in assisted reproductive technology that involves the administration of gonadotrophins. Repeated superovulations result in severe ovarian damage. The present study investigated the effect of in vivo administration of lycopene on ovarian damage induced by four successive cycles of superovulation. Superovulated mice were simultaneously administered intraperitoneally with saline (R4) or 5 mg/kg lycopene (R4-Lyc). The evaluated parameters were the count of different types of follicles, expression of ovarian antioxidant- and apoptosis-related genes, and serum concentrations of estradiol, progesterone, and inhibin-B. Increased numbers of healthy follicles and a decreased count of atretic follicles were observed in mice of the R4-Lyc group compared to those of the R4 group. Moreover, significantly higher mRNA levels of Sod3, Cat, and Nrf2 and lower mRNA levels of Keap1, Tnf, Nfkb, and Casp3, together with decreased H2O2 concentrations and increased total antioxidant capacity, were detected in the ovaries of lycopene-treated mice. Regarding serum reproductive hormones, elevated concentrations of estradiol, progesterone, and inhibin-B were evident in lycopene-administered mice. The present study reports a significant role of lycopene in alleviating the ovarian damage induced by multiple hormonal superstimulations, which could help to improve the outcomes of in vitro embryo production.

Morphometric Evaluation of the Ampullae of the Oviducts in Prepubertal Gilts Treated With Chorionic Gonadotropins.

This study assessed morphometric traits of the ampulla of the oviducts in prepubertal gilts treated with chorionic gonadotropins. With the day of slaughter as D0, gilts were assigned to four treatments (n = 8 each): control (untreated), eCG (200 IU eCG on D3), eCG+hCG (1200 IU eCG on D6 plus 500 IU hCG on D3), and eCG+hCG+AI (the previous treatment plus artificial insemination on D1). Blood and ampullae samples were collected at slaughter. Serum progesterone concentrations were higher for gilts treated with hCG than for those in the eCG and control treatments (p < 0.001), but estradiol concentrations did not differ (p > 0.05). The epithelium, muscle and lumen areas and the inner and larger ampullae diameters did not differ across treatments (p > 0.05). Therefore, treatment with chorionic gonadotropins did not alter the ampullae morphometry of prepubertal gilts.

EFFECT OF HEAT STRESS ON PRODUCTION PERFORMANCE IN DAIRY ANIMALS

The high-temperature stress and combination of high temperature and humidity during summer months in Punjab is an important factor for dairy cows as it directly affects the daily milk yield of dairy cows. The research was conducted on to effect of high-temperature stress on different parameters associated with daily milk yield. For this purpose, 5 freshly parturated Sahiwal breeds of dairy cows were to evaluate the effect of temperature humidity index on Daily milk yield at different temperature humidity index levels i.e. comfortable (≤ 70), mild stress (71–80), moderate stress (81–90), and stressful (≥90) zone. Blood samples were collected and centrifuged to get serum and ELISA was accomplished by using a spectrometer. Results revealed high significant (P &lt; 0.001) increment in cortisol and triglycerides concentration and high significant reduction in serum progesterone (P &lt; 0.001) and Luteinizing hormone (P &lt; 0.001) concentration in cows during stressful environments. Daily milk yield has significant (P &lt; 0.05) variation and a decreasing trend in cows from comfortable to stressful conditions. Progesterone and LH had a highly significant positive correlation with daily milk yield. Cortisol and triglycerides had a non-significant negative correlation with daily milk yield. It is concluded that heat stress has a negative impact on the daily milk yield as it disturbs the hormonal balance of the animal.

Knockdown of Gonadotropin-Releasing Hormone II Receptor Impairs Ovulation Rate, Corpus Luteum Development, and Progesterone Production in Gilts.

Reproduction is classically controlled by gonadotropin-releasing hormone (GnRH-I) and its receptor (GnRHR-I) within the brain. In pigs, a second form (GnRH-II) and its specific receptor (GnRHR-II) are also produced, with greater abundance in peripheral vs. central reproductive tissues. The binding of GnRH-II to GnRHR-II has been implicated in the autocrine/paracrine regulation of gonadal steroidogenesis rather than gonadotropin secretion. Blood samples were collected from transgenic gilts, with the ubiquitous knockdown of GnRHR-II (GnRHR-II KD; n = 8) and littermate controls (n = 7) at the onset of estrus (follicular) and 10 days later (luteal); serum concentrations of 16 steroid hormones were quantified by high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). Upon euthanasia, ovarian weight (OWT), ovulation rate (OR), and the weight of each excised Corpus luteum (CLWT) were recorded; HPLC-MS/MS was performed on CL homogenates. During the luteal phase, serum progesterone concentration was reduced by 18% in GnRHR-II KD versus control gilts (p = 0.0329). Age and weight at puberty, estrous cycle length, and OWT were similar between lines (p > 0.05). Interestingly, OR was reduced (p = 0.0123), and total CLWT tended to be reduced (p = 0.0958) in GnRHR-II KD compared with control females. Luteal cells in CL sections from GnRHR-II KD gilts were hypotrophic (p < 0.0001). Therefore, GnRH-II and its receptor may help regulate OR, CL development, and progesterone production in gilts.

Minimal influence of the menstrual cycle or hormonal contraceptives on performance in female rugby league athletes.

We examined performance across one menstrual cycle (MC) and 3weeks of hormonal contraceptives (HC) use to identify whether known fluctuations in estrogen and progesterone/progestin are associated with functional performance changes. National Rugby League Indigenous Women's Academy athletes [n=11 naturally menstruating (NM), n=13 using HC] completed performance tests [countermovement jump (CMJ), squat jump (SJ), isometric mid-thigh pull, 20m sprint, power pass and Stroop test] during three phases of a MC or three weeks of HC usage, confirmed through ovulation tests alongside serum estrogen and progesterone concentrations. MC phase or HC use did not influence jump height, peak force, sprint time, distance thrown or Stroop effect. However, there were small variations in kinetic and kinematic CMJ/SJ outputs. NM athletes produced greater mean concentric power in MC phase four than one [+0.41W·kg-1 (+16.8%), p=0.021] during the CMJ, alongside greater impulse at 50ms at phase one than four [+1.7N·s (+4.7%), p=0.031] during the SJ, without differences between tests for HC users. Among NM athletes, estradiol negatively correlated with mean velocity and power (r=-0.44 to -0.50, p<0.047), progesterone positively correlated with contraction time (r=0.45, p=0.045), and both negatively correlated with the rate of force development and impulse (r=-0.45 to -0.64, p<0.043) during the SJ. During the CMJ, estradiol positively correlated to 200ms impulse (r=0.45, p=0.049) and progesterone to mean power (r=0.51, p=0.021). Evidence of changes in testing performance across a MC, or during active HC use, is insufficient to justify "phase-based testing"; however, kinetic or kinematic outputs may be altered in NM athletes.

Effect of post-mating GnRH or TAK-683 (Kisspeptin analog) treatment on the reproductive performance and serum progesterone concentration in ewes during the non-breeding season

This study was designed to evaluate the effect of post-mating GnRH or TAK-683 (kisspeptin analog) treatment on serum progesterone (P4) concentrations and fertility parameters of ewes during the non-breeding season. One hundred and twenty multiparous, lactating Awassi ewes were used. For estrus synchronization, vaginal sponges containing 60 mg of medroxyprogesterone acetate (MAP) were inserted into the vagina and kept there for nine days. On the day of sponge removal (day 0), 500 IU of eCG and 75 µg of d-cloprostenol were given intramuscularly. Rams were introduced in the flock 24 h after sponge removal and kept with the ewes for 26 days, allowing a second mating period after synchronized estrus. On the fourth day after mating (day 6) the ewes mated by the rams between the 24th and 72nd hours (n = 105) were randomly divided into three groups. Control group (n = 36) received 1 ml of saline solution subcutaneously; GnRH group (n = 34) received 4 μg of buserelin acetate intramuscularly; TAK-683 group (n = 35) received 5 μg of TAK-683 acetate subcutaneously. Blood samples were taken to measure serum P4 concentrations (ng/ml) at sponge insertion and on the 6th, 9th, 12th, 15th, 19th, 35th, and 50th days after sponge removal. Pregnancy diagnosis was conducted via serum P4 concentration measurement on the 19th day and transrectal ultrasonography on days 35 and 50. The results showed that GnRH treatment (4.823 ± 0.238; 2.151 ± 0.272) increased (P<0.05) the mean P4 concentration (ng/ml) in pregnant and non-pregnant ewes during the first mating period compared to Control (3.708 ± 0.207; 1.515 ± 0.164), while TAK-683 treatment (4.457 ± 0.181; 1.967 ± 0.213) was not different between groups. GnRH (58.82 %) and TAK-683 (42.10 %) treatments increased the pregnancy rate in the second mating period in comparison to the Control group (17.39 %) (P<0.05). Cumulative pregnancy and fecundity rates were higher in GnRH (79.41 %; 120.58 %) and TAK-683 (68.57 %; 100.0 %) groups than in the Control group (17.39 %; 58.33 %) (P<0.05). There was no difference in late embryonic loss rate among the groups (P>0.05), whereas early fetal loss rate tended to be lower in the TAK-683 (0 %) and GnRH (0 %) groups than in the Control group (15.38 %) (P=0.07). The total pregnancy loss rate (from day 19 to day 50 post-mating) was lower in GnRH (0 %) and TAK-683 (0 %) groups relative to the Control group (21.42 %) (P<0.05). There were no statistical differences among the groups in terms of the first mating period pregnancy rate, twinning rate, and litter size (P>0.05). As a result, treatment with GnRH and TAK-683 on the fourth day after mating increased fecundity in lactating ewes outside the breeding season by preventing total pregnancy losses (from day 19 to day 50) and increasing second mating pregnancy rates.

Expression patterns and distribution of aquaporin water channels in cervix as a possible mechanism for cervical patency in bitches affected by pyometra

Pyometra is a life-threatening disease, the severity of which depends on cervical patency status. This study investigated cervical inflammation status as well as the expression patterns and localization of aquaporin (AQP1, AQP2, AQP3, AQP5, and AQP9), and hormone receptors in cervical tissue that influences canine pyometra. Of the 36 animals enrolled in the study, 24 were diagnosed with pyometra and separated into two groups: open cervix pyometra and close cervix pyometra, while 12 healthy animals presented for elective ovariohysterectomies were allocated into the control group. Surgical treatment was performed for treatment of pyometra. After each operation, cervix samples were collected and analyzed for AQP and hormone receptor expression patterns determined by qPCR and protein expression by means of immunohistochemistry. Blood samples were also collected to determine serum progesterone concentrations. AQP9 expression was downregulated approximately 3-fold while and PGR expression was downregulated more than 2 fold in both pyometra groups compared to the control group. AQP3 and AQP5 gene expression levels were upregulated more than 3 fold in the open-cervix pyometra group than the closed-cervix pyometra group (P < 0.05). This is the first study to describe the expression patterns and immunolocalization of AQPs in canine cervical tissue based on pyometra patency status and to report AQP3 and AQP5 expression in cervical tissue linked to cervical patency.

Evaluating impact of season and corpus luteum cavitation on serum progesterone concentration and pregnancy in a Holstein dairy herd

The corpus luteum (CL) is vital to bovine reproduction and can present in 2 forms on ultrasound examination: homoge­neous or cavitary. Impact of CL cavitation on fertility in cattle has been debated. Many variables influence fertility includ­ing heat stress, but little is known regarding the impact of season and risk of association with a cavitary CL. The objec­tives of this study were to evaluate: (1) effect of CL form on serum progesterone, and (2) effect of reproductive status and season on the likelihood of diagnosing a cavitary CL. Blood from Holstein cows (n = 787) on a commercial dairy farm was collected (n = 1,062) at 39-45 days post-insemination. Some cows were sampled more than once. Corpora lutea were categorized as homogeneous or cavitary, and cows were diagnosed as either pregnant or non-pregnant via transrectal ultrasonography at time of blood collection. When adjusted for season and CL status, pregnant cows produced higher serum progesterone (6.880 ng/mL; 95% CI [6.606, 7.153]) than non-pregnant cows (4.664 ng/mL; 95% CI [4.398, 4.931], P &lt; 0.001). When adjusted for progesterone levels and season, pregnant cows were 94.7% less likely (OR = 0.053, P &lt; 0.001) to be diagnosed with a cavitary CL com­pared to non-pregnant cows. No difference was observed in serum progesterone by CL form (P = 0.393). Serum progester­one was significantly lower in summer than fall (P &lt; 0.001), winter (P &lt; 0.001) and spring (P = 0.005). Season did not impact likelihood of diagnosing a cavitary CL.