Blood Progesterone Concentrations Research Articles

Individual hormonal profiles of blood progesterone and estradiol-17β during the course of a reproductive cycle in mares

This study presents the individual course of estradiol-17ß and progesterone concentrations in blood during the reproductive cycle in mares in order to point out physiological differences between individual animals and to aid in the interpretation of hormone values. Concentrations of estradiol-17ß and progesterone were determined in seven mares over the course of their cycle. One mare was excluded from the study due to a physiologically deviating cycle. In addition, the mares' ovaries were examined via ultrasound on a daily basis in order to match the hormone values to morphological changes of the ovaries. In some cases, the mares showed considerable individual differences in their hormone concentrations, which also differed from the published comparative values in the literature. For example, two mares showed progesterone levels above basal levels at the time of ovulation. The postovulatory progesterone concentrations of the mares are characterized by marked fluctuations, which makes it difficult to provide reference values in the different sections of the corpus luteum phase. The length of the plateau phases averaged 12.3±1.5 days. The mare with double ovulation showed the highest progesterone concentrations. The measurement of plasma progesterone levels in mares should be interpreted only in the context of other test results. The very wide variation in estradiol-17ß concentrations makes it questionable whether the determination of this hormone value is of diagnostic value. When interpreting steroid hormone values in the ingravid cycle of a mare, the individual concentration courses must be taken into consideration, as they may deviate significantly from the published reference values.

Recent advances in early pregnancy loss diagnosis in dairy cows: New approaches.

Early pregnancy loss is a primary cause of low reproductive rates in dairy cows, posing severe economic losses to dairy farming. The accurate diagnosis of dairy cows with early pregnancy loss allows for oestrus synchronization, shortening day open, and increasing the overall conception rate of the herd. Several techniques are available for detecting early pregnancy loss in dairy cows, including rectal ultrasound, circulating blood progesterone, and pregnancy-associated glycoproteins (PAGs). Yet, there is a need to improve on existing techniques and develop novel strategies to identify cows with early pregnancy loss accurately. This manuscript reviews the applications of rectal ultrasound, circulating blood progesterone concentration, and PAGs in the diagnosis of pregnancy loss in dairy cows. The manuscript also discusses the recent progress of new technologies, including colour Doppler ultrasound (CDUS), interferon tau-induced genes (ISGs), and exosomal miRNA in diagnosing pregnancy loss in dairy cows. This study will provide an option for producers to re-breed cows with pregnancy loss, thereby reducing the calving interval and economic costs. Meanwhile, this manuscript might also act as a reference for exploring more economical and precise diagnostic technologies for early pregnancy loss in dairy cows.

Temporal changes in ewe vaginal microbiota throughout gestation.

Numerous factors are known to influence reproductive efficiency in ewes, but few studies have investigated the potential role of vaginal microbiota in sheep reproductive success. The objective of this study was to thoroughly characterize the ewe vaginal microbiota throughout the course of pregnancy. Vaginal samples were collected from 31 pregnant Hampshire and Hampshire X Suffolk crossbred ewes on a weekly basis from pre-breeding to pregnancy testing and then biweekly until just after lambing. To characterize the vaginal microbial communities, DNA was extracted and 16S rRNA gene Illumina MiSeq amplicon sequencing was performed. Alpha diversity metrics indicated an increase in species richness, evenness, and overall diversity throughout gestation. Distinct shifts in the bacterial communities were observed during gestation and were segregated into three periods: early gestation, a transitional period and mid/late gestation. During early gestation, Actinobacillus, Histophilus, and unclassified Leptotrichiaceae were found in greater relative abundance. During the transitional period, a population shift occurred characterized by increasing relative abundance of Streptococcus and Staphylococcus. During mid/late gestation, Staphylococcus, Streptococcus, and Ureaplasma had the greatest relative abundance. These shifts in the microbial population throughout the ewe's gestation are likely related to hormonal changes triggered by the growing conceptus, specifically increasing blood concentration of progesterone. The transitional period shift in vaginal microbial communities potentially aligns with the placental take-over of progesterone production from the corpus luteum at approximately day 50 after conception (gestational week 7). Understanding the observed variability of the vaginal microbiota throughout pregnancy will allow for future comparison of ewes that did not become pregnant or had abnormal pregnancies, which could lead to the discovery of potential bacterial biomarkers for pregnancy outcome; this understanding could also lead to development of probiotics to improve sheep reproductive success.

Improved the invitro blastocyst development in oocytes recovered from cyclic buffaloes.

This study examined the impact of cyclicity (with or without cycle corpus luteum; CL) on oocyte quality and embryonic development in buffaloes. We collected oocytes from the ovaries of slaughtered buffaloes (N = 158 cyclic; n = 316 ovaries and N = 177 acyclic; n = 353 ovaries). Blood progesterone concentration and number of oocytes per ovary were higher in cyclic buffaloes. Cyclic buffalo ovaries produce higher oocytes with I + II and fewer III + IV grades. Oocytes from cyclic buffaloes had a higher maturation rate based on cumulus expansion, cleavage rate and embryo development to the 8-cell, morula and blastocyst stages than acyclic buffaloes. In conclusion, oocytes recovered from the ovaries of the cyclic buffaloes showed improved oocyte competence and subsequent invitro blastocyst development.

Effects of Maternal Cigarette Smoking on Trace Element Levels and Steroidogenesis in the Maternal-Placental-Fetal Unit.

This study evaluates the interaction of toxic elements cadmium (Cd) and lead (Pb) due to exposure from cigarette smoking, essential elements, and steroidogenesis in the maternal-placental-fetal unit. In a cohort of 155 healthy, postpartum women with vaginal term deliveries in clinical hospitals in Zagreb, Croatia, samples of maternal blood/serum and urine, placental tissue, and umbilical cord blood/serum were collected at childbirth. The biomarkers determined were concentrations of Cd, Pb, iron (Fe), zinc (Zn), copper (Cu), and selenium (Se), and steroid hormones progesterone and estradiol in maternal and umbilical cord blood and the placenta. Three study groups were designated based on self-reported data on cigarette smoking habits and confirmed by urine cotinine levels: never smokers (n = 71), former smokers (n = 48), and active smokers (n = 36). Metal(loid)s, steroid hormones, urine cotinine, and creatinine levels were analyzed by ICP-MS, ELISA, GC-MS, and spectrophotometry. Cigarette smoking during pregnancy was associated with increased Cd levels in maternal, placental, and fetal compartments, Pb in the placenta, and with decreased Fe in the placenta. In active smokers, decreased progesterone and estradiol concentrations in cord blood serum were found, while sex steroid hormones did not change in either maternal serum or placenta. This study provides further evidence regarding toxic and essential metal(loid) interactions during prenatal life, and new data on sex steroid disruption in cord serum related to cigarette smoking. The results indicate that umbilical cord sex steroid levels may be a putative early marker of developmental origins of the future burden of disease related to harmful prenatal exposure to cigarette smoke.

Morphologic, Steroidogenic, and Transcriptomic Assessment of the Corpus Luteum in Holstein Cows after Spontaneous or Hormone-Induced Ovulation.

There is evidence that replacing the gonadotropin-releasing hormone (GnRH) with porcine luteinizing hormone (pLH) to synchronize ovulation prior to artificial insemination (AI) increased pregnancy per AI in dairy cows without affecting blood progesterone (P4) concentrations. Whether morphologic, steroidogenic, and transcriptomic differences exist among corpora lutea (CL) formed after ovulation induced by GnRH and pLH is unclear. Our main objective, therefore, was to compare CL characteristics between GnRH- and pLH-induced CL. In 24 non-lactating Holstein cows, ovulations were spontaneous (Spont-Ov) or induced with 100 µg GnRH, 25 mg pLH, or 1 mg estradiol benzoate (EB), with CL excised 12 d after ovulation. In pLH- versus GnRH-treated cows, the duration of elevated LH (above baseline) was prolonged (10 versus 6 h, respectively, p < 0.01), but CL dimensions, pixel intensity of CL images, proportions of steroidogenic and non-steroidogenic luteal cells, and mean plasma LH did not significantly differ. Post-ovulation mean plasma P4 (ng/mL) did not differ among Spont-Ov (3.0) pLH (3.1) or GnRH (3.0) cows but were lower in EB cows (2.0). In vitro P4 concentration was greater in luteal explants of pLH-treated cows than in all other groups (combined means, 16.0 vs. 12.3 µg/mL, p < 0.02). Relative abundance of mRNA for oxytocin receptor (OXTR) was 2-fold higher (p < 0.01) in CL of pLH vs. GnRH cows and highest in Spont-Ov CL. In summary, pLH-treated cows had a longer LH peak, and greatest luteal tissue concentrations and in vitro production of P4. We inferred that increased P4 concentrations at the ovarian-uterine level in pLH-treated cows could have promoted embryo development and increased pregnancy per AI.

Выбор оптимального времени и методы искусственного осеменения собак

We collected, analyzed, and summarized information on the optimal timing and methods of artificial insemination of dogs at present. Scientific articles published in the bibliographic databases such as e-library, Scopus, and ResearchGate were used for this review. It has been established that artificial insemination has significant advantages over natural insemination, including reliable long-term storage of sperm in cryobanks, the possibility of exporting and importing genetic material without transporting animals, and obtaining offspring from elite male producers from anywhere in the world, even after their death.&#x0D; The time of artificial insemination and natural mating is determined by the date of ovulation using direct (ultrasound visualization of the ovaries) or indirect methods (picture of vaginal smears, multiple measurements of blood progesterone concentration, etc.). In dogs, the egg cell ovulates immature at the stage of the oocyte of the first order. For this reason, it is recommended to inseminate them on the 2nd… 5th days after ovulation, when egg maturation ends in the fallopian tube - the formation of a second-order oocyte.&#x0D; For dog insemination, freshly obtained, diluted chilled, and cryopreserved sperm are used. When using freshly obtained and diluted cooled sperm, the method of choice is an intra-vaginal method of sperm administration, and frozen-thawed sperm requires transcervical intrauterine insemination under video endoscopic control.

Effect of uterine torsion intrapartum on concentrations of placental estrogens and progesterone in cattle.

The current study investigates how uterine torsion influences placental oestrogens and progesterone blood concentrations in intrapartum cows. Our research tests the hypothesis that intrapartum uterine torsion impairs the ability of the placenta to synthesize steroids and may also suppress the release of synthesized steroids into the maternal circulation. The study included a total number of 37 intrapartum dairy cows of various breeds and ages. These animals were transported to our clinic by their owners. Furthermore, general and obstetrical examinations of all these animals were performed in our clinic. The uterine torsion (UT) group consisted of 20 animals. The presence of UT was verified during clinical general examinations by vaginal and transrectal examination. The comparison (C) group included 17 animals whose birth was undisturbed or could be terminated with moderate obstetrical assistance. The clinical examination of group C animals showed no problems with their general health and genital organs. Blood samples were collected immediately after the initial obstetrical examination from 37 cows for radioimmunological measurement of estradiol-17β (E2), free total estrogen (FTE), conjugated total estrogen (CTE), and progesterone (P4). In terms of P4, there was no statistical difference between the two groups. For all estrogen parameters, however, concentrations were significantly lower in the UT group than in the C group. In the correlation analysis, there was a significant correlation between the P4 and the FTE in the C group. Furthermore, the positive correlation between all estrogen parameters in the UT group was significant. In group C, significant positive correlations were found apart from the correlation between E2 and CTE. The results are consistent with the hypothesis and suggest that in UT animals processes dependent on estrogens or other placental hormones may be impaired during the peri- or postpartum period.

Successful mule embryo transfer to a recipient mule during late diestrus

Mating between a donkey (Equus asinus) and a mare (Equus caballus) results in a mule foal, which is an infertile hybrid due to the different number of chromosomes in the parent species. However, mules have been successfully used as recipients of donkey embryos, horse embryos and, recently, mule embryos. In non-cyclic recipient mules, progesterone supplementation is needed to sustain pregnancy, but some mules can develop pre-ovulatory follicles which ovulate and form active CLs that produce enough progesterone to sustain pregnancy. In spite of this, it is possible that the induction of additional CL formation to increase progesterone concentrations prior to embryo transfer could increase the chances of successful pregnancy. In this study an 8-day old mule embryo produced by the insemination of a mare with fresh donkey semen was transferred to a cyclic mule that had been induced to form a secondary CL by the injection of 1.8mg of deslorelin acetate on day 8 post-ovulation, when a spontaneously developed follicle reached 38 mm of diameter. Progesterone concentrations at that time confirmed that the primary CL was active. Secondary ovulation occurred 2 days later and a secondary CLformed during the following days, resulting in a significant increase in blood progesterone concentrations. The 8-day old embryo was transferred nine days after the secondary ovulation (19 days after the primary ovulation), when both the primary and secondary CL were fully active as indicated by sustained progesterone concentrations and by their diameters of 37 and 35.5 mm, respectively. Pregnancy diagnosis was made 4 days after transfer of the embryo, that is, 23 days after the primary ovulation and 13 days after the secondary ovulation. At that time, the 12-day old embryo was within a 15mm embryonic vesicle. On days 55 and 58 of pregnancy two new supplementary CL formed spontaneously, reaching diameters of 36 and 29mm. This report of a successful mule-in-mule pregnancy using as a recipient a mule with both a primary and an artificially induced secondary CL suggests the possibility of improving the chances of successful pregnancy in recipient mules by increasing endogenous progesterone production through induction of secondary ovulations prior to embryo transfer. Acknowledgements. This study was supported by grant PAPIIT IN 223920, DGAPA-UNAM.

Effects of two protocols of ovulation synchronization on corpus luteum size and blood flow, progesterone concentration, and pregnancy rate in beef heifers

The objective of this study was to evaluate the effect of 7-day estradiol-progesterone-based [Treat(C)] and 5-day Co-Synch plus progesterone [Treat(Co-Sy)] protocols on ovulation time, pre-ovulatory follicle diameter, corpus luteum (CL) size and blood flow, progesterone (P4) concentration and pregnancy rate (PR) in beef heifers. In Experiment 1, a crossover design was applied (n = 9). For Treat(C), a progesterone intravaginal (PI) device was inserted, plus 2 mg of estradiol benzoate (day 0). On day 7, 500 µg of cloprostenol plus 0.5 mg of estradiol cypionate were administered, and PI was removed. For Treat(Co-Sy), on day 0, a PI was inserted plus 100 µg gonadotropin-releasing hormone (GnRH). On day 5, PI was removed, plus 500 µg of cloprostenol and 100 µg of GnRH were administered at 69–70 h later. From day one to ovulation day, dominant follicle was evaluated by ultrasonography. On days 4 and 8 post-ovulation, CL was evaluated by color Doppler, and P4 concentration was determined by chemiluminescence. In Experiment 2, a split-plot experimental design was used. Protocols followed were the same as in Experiment 1 [Treat(C); n = 310 and Treat(Co-Sy); n = 314]. Heifers were fixed-time artificially inseminated. Pregnancy was determined on day 41. In Experiment 1, the interval between PI removal and ovulation time was different between protocols (P < 0.01). In addition, P4 concentration was related to the CL size (P < 0.001), CL blood flow (P < 0.01) and protocols (P < 0.03). In Experiment 2, PR did not differ between protocols.

Comparative analysis of biochemical, hormonal, and mineral compositions of preovulatory and cystic ovarian follicles in buffalo during the non-breeding season.

This study is a comparative analysis of the biochemical, hormonal, and mineral compositions of follicular fluid in preovulatory and cystic follicles of water buffalo (Bubalus bubalis). In total, reproductive tracts from 215 buffalo along with intact ovaries were collected randomly from an abattoir. The incidence of cystic conditions found in this study was 3.72% (8/215), involving the right ovary in 62.5% of instances and the left ovary in 37.5% of instances during the non-breeding season. Follicular fluid was aspirated from preovulatory follicles (12-15 mm diameter, oestrogen-active, follicular phase or stage IV corpus luteum on one of the two ovaries, n = 10) and cystic follicles (at least 20 mm diameter, no corpus luteum on any one of the two ovaries, n = 8). The follicular fluid samples were assayed for biochemical components (uric acid, creatinine, blood urea nitrogen, cholesterol, total protein, glucose, ascorbic acid, and alkaline phosphatase), hormones (progesterone, estradiol, and insulin), and minerals (calcium, magnesium, phosphorus, copper, zinc, and cobalt). Cystic follicles had greater (P < 0.05) concentrations of creatinine, blood urea nitrogen, cholesterol, progesterone, copper, zinc, and cobalt, and lesser (P < 0.05) concentrations of uric acid, glucose, ascorbic acid, estradiol, insulin, calcium, magnesium, and phosphorus compared with preovulatory follicles. These results indicated the marked differences in follicular fluid composition between preovulatory and cystic follicles in buffalo. Some of the changes were indicative of oxidative stress and disturbed steroidogenesis, two important mechanisms shown to be associated with cystic ovarian disease in various species. Further studies are warranted to investigate whether these differences are directly or indirectly involved in the formation of cystic follicles or are mere manifestations of the condition.

Effect of prolidase on the development of varicose veins in pregnant women

Introduction and Aim: Varicose veins are more common during pregnancy and, if left untreated, can cause venous insufficiency and edema in the legs. Women have venous insufficiency both before and after pregnancy. According to research, the cytosolic metalloproteinase prolidase regulates the breakdown of collagen and other proteins in the extracellular matrix. Prolidase deficiency, which impairs the enzyme's normal function, has severe clinical manifestations. The objective of this study is to discover how the enzyme prolidase influences the development of varicose veins in pregnant women.&#x0D; &#x0D; Materials and Methods: This study included approximately 70 women aged 25-45 years who were pregnant in their third trimester. The participants were assigned to two groups based on diagnosis of having varicose veins (n=40) and those without (n=30). Quantitative measurements of serum progesterone and prolidase concentrations were made. Data collected was subjected to statistical analysis.&#x0D; &#x0D; Results: Varicose veins were prevalent in 57.14% of the pregnant women, the severity of which increased with age. The mean blood concentrations of progesterone and prolidase levels were higher in pregnant women with varicose veins in comparison to controls.&#x0D; &#x0D; Conclusion: Chronic venous insufficiency and mild varicose veins are more common in pregnant women aged 40 years and above. An increased level of progesterone and prolidase enzyme in serum was seen to be associated with chronic varicose insufficiency in pregnant women.

Estratégias de suplementação pré e pós-parto no desempenho e no estado metabólico de vacas de corte em pastejo

Abstract The objective of this work was to evaluate the effect of energy-protein supplementation in preand postpartum periods on the productive and metabolic responses of grazing beef cows on tropical pasture. A group of 48 multiparous Nellore cows, with an initial gestation period of 6.4 months, body weight (BW) of 514.9 kg, and body condition score (BCS) of 5.4, was distributed in a completely randomized design, in a 2×2 factorial arrangement. The evaluated treatments were: UNS-UNS, unsupplemented during prepartum and postpartum; UNS-SUP, unsupplemented during prepartum and supplemented during postpartum; SUP-UNS, supplemented during prepartum and unsupplemented during postpartum; and SUP-SUP, supplemented during preand postpartum. The energy-protein supplement was offered at an amount of 1.5 kg per animal per day. Prepartum supplementation increased average daily gain and BCS at calving. Prepartum supplementation reduced non-esterified fatty acids (NEFA) and increased serum concentrations of total proteins and globulins during postpartum. Postpartum supplementation increased the BCS of cows and BW of calves at the end of the experiment. Postpartum supplementation increased blood concentrations of progesterone, while NEFA decreased. Supplementation with 1.5 kg per day of the energy-protein supplement during the last 84 days of gestation improves productive performance and metabolic status during the preand postpartum periods of grazing cows.

Effects of tocolytic drugs (isoxsuprine hydrochloride) during the implantation period in pregnant sheep.

In this study, the effects of isoxsuprine hydrochloride applied 14 and 15 days after insemination in Anatolian Merino Sheep on lamb yield and some blood parameters were investigated. The research was conducted during the breeding season and 54 ewes inseminated on the same day were used. The ewes were assigned to three groups. Group I: For the placebo effect, physiological saline was injected on the 14th day into half of the control group and on the 15th day into the other half after insemination (n=18). Group II: Tocolytic drug was injected on the 14th day after insemination (n=18). Grop III: Tocolytic drug was injected on the 15th day after insemination (n=18). As the tocolytic drug, isoxsuprine hydrochloride (HCl) 3 ml (Utelax, Sanovel, Türki̇ye) was used intramuscularly. The number of pregnant and viviparous ewes, single and multiple birth ewes, lambs per viviparous ewes were determined as reproductive parameters. Blood progesterone, cortisol and calcium concentration were determined. As a result, it was determined that the single application of isoxsuprine hydrochloride (3 ml) in the implantation period did not have a positive or negative effect on reproductive parameters, and did not change the blood progesterone, calcium and cortisol concentration in ewes.

Association of bovine viral diarrhea virus, bovine herpesvirus 1, and Neospora caninum with late embryonic losses in highly supplemented grazing dairy cows

The objectives of this study were: 1- to evaluate the association of Bovine Viral Diarrhea Virus (BVDV), Bovine Herpes Virus 1 (BoHV-1), and Neospora caninum (N. caninum) with the risk for Late Embryonic Loss (LEL) in grazing dairy cows, 2- to evaluate blood progesterone concentration at the time of LEL occurrence, and 3- to describe a novel ultrasound-guided technique for conceptus sampling. We run a prospective cohort study involving 92 cows (46 LEL and 46 NLEL). An LEL cow was that having an embryo with no heartbeat, detached membranes, or floating structures, including embryo remnants detected at pregnancy check by ultrasonography (US) 28–42 days post-AI, whereas an NLEL cow was that with embryo heartbeats detectable by US at pregnancy check 28–42 d post-IA. We took two blood samples from every cow at pregnancy check by US (the day of LEL detection) and 28 d later to perform serological diagnosis of BVDV, BoHV-1, and N. caninum; and to measure blood progesterone concentration at pregnancy check (28–42 d post-AI). We also sampled the conceptus from all the LEL cows. We performed PCR to detect BVDV, BoHV-1, and N. caninum in sampled conceptuses from LEL cows. Finally, we evaluated the associations of risk factors (serological titers, seroconversion, and progesterone) with LEL odds with logistic models. The risk for LEL was associated with serological titers to BVDV (P = 0.03) and tended to be associated with seroconversion to BVDV, given that 19.6% (9/46) in LEL and 6.5% (3/46) in NLEL cows seroconverted to BVDV (P = 0.09). In addition, BVDV was detected in conceptuses from LEL cows that seroconverted to BVDV but not in LEL cows that did not seroconvert. Conversely, the risk for LEL was not associated with the titers or seroconversion to BoHV-1 and N. caninum. BoHV-1 and N. caninum were not identified in any of the conceptuses. Finally, blood progesterone concentration was similar in LEL and NLEL cows, and it was not associated with the risk for LEL (P = 0.54). In conclusion, BVDV infection is a risk factor for LEL in dairy cows.

PSVI-5 Treatment of Flunixin Meglumine and Prostaglandin E2 had no Effect on Corpora Lutea of Beef Cows

Abstract Flunixin meglumine (FM) is a COX enzyme inhibitor and prostaglandin E2 (PGE) builds the corpus luteum (CL). However, the use of FM in conjunction with PGE has not been studied. The objective of this study was to determine effects of intravenous administration of FM and intravaginal release of PGE on characteristics of the CL and concentrations of PGE and progesterone in blood. Beef cows (n = 24, divided between two replicants over time) were synchronized using the Select Synch + CIDR protocol (expected estrus = d 0). Cows were randomly assigned to one of four treatment groups in a factorial arrangement, with 6 cows in each: Control, FM, PGE, or FM+PGE. Treatments were administered from d 13 to 19 (FM 2.2 mg/kg iv every 12 hr; PGE released in osmotic pump at 0.1 mL/d). Every other day from d 0 to 26, transrectal ultrasonography with color Doppler was used to measure size and blood perfusion of CL; images were later analyzed with ImageJ. Blood samples were collected via jugular venipuncture every other day from d 13 to 26 and later analyzed for concentrations of progesterone (P4; RIA) and PGE (ELISA). Data were analyzed using the mixed procedure of SAS 9.4 with day as a repeated measure; significance was declared when P ≤ 0.05. There were no interactions between FM and PGE, thus main effects of treatments were evaluated. There were no differences (P ≥ 0.164) in size, vessel density, or blood perfusion of CL between treatment groups. There were no differences (P ≥ 0.141) in concentrations of PGE or P4 between treatment groups. However, concentrations of P4 and PGE and density of blood vessels decreased by day (P ≤ 0.05). In conclusion, treatment with FM or PGE did not influence CL characteristics nor concentrations of P4 or PGE in circulation.

81 Effects of Hurricane-Related Stress During Gestation on Replacement Heifer (Bos Taurus) Development in a Limited-Resource Beef cow-Calf System

Abstract In a limited resource cow-calf operation, obtaining puberty in heifers is one of the main concerns for long-term productivity. Although nutritional factors have a large role in heifer development, environmental factors are sometimes overlooked until a catastrophic event such as a hurricane occurs. For this project, two heifer groups, born in the same herd at different intervals, were compared: Group 1(experienced catastrophic hurricane event in 3rd trimester of their fetal development) and Group 2 (no adverse event during gestation). The groups were weighed four similar time points during development: at 12 months of age (Period 1, pre-pubertal), 13-14 months (Period 2, puberty), pre-breeding (Period 3), and at the end of breeding (Period 4). The blood cortisol, glucose, and progesterone concentrations were compared between the groups during their pre-pubertal period. Group comparisons were performed using mixed procedures of SAS. Data are presented as means ±SEM. Group mean differences were declared significant at P &amp;lt; 0.05. We observed a significant (P &amp;lt; 0.01) Group by Period effect on heifer body weight (655.2± 14.2 vs. 747.3 ±15.4, for Groups 1 and 2, respectively). Overall, Group 1 was lighter than Group 2 in periods 1 and 2, but there was no difference thereafter. There were significant group differences in glucose (60.5± 8.8 vs 95.3±11.5, mg/dL for groups 1 and 2 respectively, P&amp;lt; 0.01) and progesterone (62.2±12.6 vs 124.0± 13.8, pg./mL for groups 1 and 2, respectively, P&amp;lt; 0.01). However, there was no significant difference in cortisol concentrations (P&amp;lt; 0.48). Therefore, catastrophic weather events such as hurricanes that are common throughout the world might have a negative impact on heifer development, as observed in this project. This observation warrants further investigation. Funding agency: USDA- NIFA CBG #2021-38821-34599

PSXII-4 Estrus Synchronization and Artificial Insemination in Korean Black Goats Using Frozen-Thawed Semen

Abstract Korean black goat (Capra hircus coreanae) populations are dwindling and facing genetic erosion due to artificial insemination. Here, we introduced an estrus synchronization method for Korean black goats to enable crossbreeding with non-native breeds on small farms and investigated the application of estrus synchronization and artificial insemination in Korean black goats. Semen was obtained using electro-ejaculation and preserved using a conventional and simple freezing method. Pre- and post-freezing semen was analyzed using computer-assisted sperm analysis, as per the Food Standards Agency 2011 guidelines. The percentage of motile sperm in the electro-ejaculated samples declined significantly after freezing and thawing. However, this did not influence the artificial insemination results. In addition, the incubation period was positively correlated with sperm motility decline in the frozen-thawed sperm samples. Blood progesterone (P4) and estrogen (E2) concentrations were also analyzed to determine the optimal artificial insemination time in estrus-synchronized Korean black goats. The blood samples were collected from a jugular vein at approximately 0900 daily for 5 days. Subsequently, the serum was obtained using centrifugation and stored at -70°C until analysis. Although the P4 and E2 concentrations were generally unaffected by the estrous synchronization method, the controlled internal drug release + prostaglandin F2α + pregnant mare serum gonadotropin method yielded a 42.9% parturition rate after artificial insemination. In the present study, an offspring from an estrus-synchronized Korean black goat was successfully produced by artificial insemination using frozen-thawed semen. The successful cryopreservation of semen for artificial insemination was substantiated with sperm motility and pregnancy rates. In the future, additional studies of estrus synchronization for the artificial insemination of Korean black goats are needed. Our results are expected to significantly contribute to the Korean black goat breeding industry.

Bacterial Communities of the Uterus and Rumen During Heifer Development With Protein Supplementation

Bacterial communities play major roles in rumen and uterine function toward optimal animal performance and may be affected by changes occurring during heifer development such as nutritional supplementation for optimal growth and the attainment of puberty. The effect of different levels of protein supplementation on ruminal and uterine bacterial communities following weaning was examined through first breeding of heifers. Angus heifers (n = 39) were blocked by initial body weight (BW) and randomly assigned to one of three 163-day (d) crude protein (CP) supplementation diets including control (10% CP, n = 14), 20% CP (n = 11), or 40% CP (n = 14) treatment groups. Growth and development were monitored by body weight, with blood progesterone concentration determined every 14 d to determine pubertal status. Uterine flush and rumen fluid were collected on d 56, 112, and 163 relative to the start of supplementation. Bacterial DNA was extracted from fluid samples, the V1–V3 hypervariable region of the 16S rRNA gene was amplified, and amplicons were sequenced then processed in R 4.1. Statistical analyses were performed in SAS 9.4 with a GLIMMIX procedure utilizing fixed effects of protein, month, pubertal status, and interactions, with random effects including BW, interaction of BW and protein, and heifer within the interaction, and repeated measures of day. In the uterus, pubertal status and day of supplementation affected the observed amplicon sequence variants (ASVs) and led to clustering of samples in a principal coordinate analysis (PCoA; P &amp;lt; 0.05), but no effect of protein supplementation was observed. Ruminal samples clustered in PCoA (P = 0.001), and observed ASVs were impacted over time (P &amp;lt; 0.0001), but no effect of protein supplementation was detected. In contrast, protein supplementation, pubertal status, and day of supplementation affected the abundance of multiple phyla and genera in the uterus and rumen (P &amp;lt; 0.05). Temporal and pubertal status effects on the heifer’s uterine bacterial communities potentially indicate a maturing uterine microbiome. Protein supplementation did not impact microbial diversity measures but did affect the abundance of individual bacterial phyla and genera that may provide future opportunities to manipulate bacterial community composition and maximize productivity.

Effect of adding carrots as feed supplementation on reproductive performance in Awassi ewes

The present study was designed to estimate the effect of carrots supplementation on reproductive performance in ewes. Thirty Awassi ewes. Ewes were randomly divided into three equal groups, distributed as 10 ewes for each group. First group consider as control, second group feed 400 g carrot/animal daily, third group feed 800 g carrot/animal daily. Each group were synchronized with intra vaginal sponges and injected with 400 IU of eCG at the time of sponge withdrawal. Estrus ewes were conceived naturally with rams and pregnant ewes were followed until parturition. The results of current study demonstrated that G3 had high estrus response and fertility rate 90% compared with G2 and control 80 and 70% respectively. Fecundity rate increased significant in G3 200% compared to G2 and 125 and 100% respectively. Ewes in G3 showed the highest multiple lambing rate 66.67% compared with G2 25% and control 0%. Blood progesterone concentration was high increasing at the 18th day of estrus in the ewes for G3 and G2 compared with control, also, estrogen level at the day of estrus showed high increasing in G3 compared with G2 and control group. We concluded that carrots fed as a supplementation have essential effect on enhancement of reproductive performance in ewes.