Blood Progesterone Concentrations Research Articles

Determining pregnancy status in harbour seals using progesterone concentrations in blood and blubber

Pregnancy status in harbour seals can be estimated from concentrations of progesterone in blubber as well as in blood samples, which are significantly higher in pregnant than non-pregnant animals. This study investigated the accuracy of estimating pregnancy rates using samples from live-captured and released harbour seals from three regions around Scotland, coupled with observed pregnancy outcomes. Concentrations of progesterone in blood (plasma) and blubber were obtained during the capture of animals early in the year (February to May). Individual animals were identified from the unique markings on their pelage, with a proportion (n = 51) of females re-sighted during the subsequent breeding season and the reproductive outcomes determined (pregnant or possibly non-pregnant) during observations from long-term photo-identification studies. Generalised linear models with a binomial link function were fitted to training (60% of the data) and test datasets (40% of the data) to estimate pregnancy status from progesterone concentrations in blubber, plasma or both, and a received operating curves (ROC) approach was used to evaluate the performance of each classifier. The accuracy for the plasma concentrations was 85% with a high classification performance (as estimated from an area under the curve (AUC) of 0.82). The Youden method to determine the cut-point (threshold) and bootstrapping the training dataset resulted in a cut-point of 58 ng ml−1 (95th percentiles, 25–102 ng ml−1). For blubber, the accuracy was 77% (AUC = 0.86) with an optimal cut-point of 56 ng g−1 (95th percentiles, 26–223 ng g−1). In the combined analysis (both blubber and plasma), the accuracy was 87.5% (AUC 0.81) with the cut-points of 72 ng ml−1 (95th percentiles, 25–103 ng ml−1) in plasma and 56 ng g−1 (95th percentiles, 26–223 ng g−1) in blubber. These thresholds were then used to estimate the pregnancy proportions among adult females at the three study sites, including those that were not included in the photo-id studies. Proportions were high at all sites, (63%–100%) regardless of which matrices were used and were not statistically significantly different from each other but suggested that analysing concentrations in both sample matrices would minimise the uncertainty.

Effect of organic selenium on blood progesterone, metabolites, milk yield and service period of Jersey cows

The aim of this study was to determine the effect of yeast based organic selenium (Se) on post-partum progesterone concentration, blood metabolites, service period and milk yield. Dairy Jersey cows (n=15) having almost similar body weight, age, parity and body condition score were divided into three groups of equal number. One group served as a control that was given no Se supplementation. Second and third groups were supplemented with Se at the rate of 0.3 and 0.4 mg/kg of dry matter intake, respectively. The results revealed that after parturition, there was significantly (P<0.05) higher concentration of progesterone in Se treated group of Jersey cows (P<0.05). Week wise, concentration of progesterone in blood increased significantly (P<0.05). There was a decrease in length of service period in Se treated groups. Blood concentrations of glucose, cholesterol and triglyceride increased significantly (P<0.05) on weekly basis. However, these blood metabolites did not change significantly between the control and Se treated groups. Milk yield did not change significantly between the control and Se treated groups. The results of current study indicated that supplementation of yeast based organic Se at the rate of 0.4 mg/kg dry matter intake improved the progesterone concentration and decreased the service period but had no effect on blood metabolites and milk yield.

High binding site occupancy of corticosteroid-binding globulin by progesterone increases fetal free cortisol concentrations

ObjectiveCorticosteroid-binding globulin (CBG) binds and transports cortisol in the circulation in high cortisol-binding affinity (haCBG) and low affinity (laCBG) forms, the latter resulting from enzyme cleavage to target cortisol delivery at sites of inflammation. CBG also has substantial progesterone binding affinity, 3-fold less than cortisol. Progesterone and cortisol are important in the maintenance of pregnancy and in fetal development, respectively. The interactions of cortisol, progesterone and CBG affinity forms have not been studied together. We examined the interaction between progesterone and cortisol with CBG during fetal development. Study designA retrospective cohort analysis of 351 neonates born between January and December 2012 at the Women's and Children's Hospital, Adelaide, South Australia. Cord blood serum samples were collected immediately following delivery. Clinical data was provided by hospital records. Total cortisol, free cortisol, total progesterone, total CBG and haCBG were measured by immunoassay. ResultsCord blood total and free cortisol, and progesterone concentrations increased with gestational age. Cord blood progesterone concentrations were 100-fold luteal and 10-fold those in late pregnancy maternal circulation. The proportion of haCBG to total CBG was similar to that in healthy non-pregnant adults. However, free cortisol comprised approximately 15% of total cortisol, 3-fold higher than that in adults. ConclusionIn a manner unique to fetal life, very high progesterone concentrations are capable of elevating free cortisol concentrations through competition with cortisol at CBG’s hormone binding site, without altered binding affinity through CBG cleavage or altered CBG hormone-binding affinity. High circulating fetal progesterone concentrations compete for CBG binding with cortisol, leading to a 3-fold increase in the free cortisol fraction in cord blood. Higher free-to-bound cortisol may alter fetal cortisol distribution facilitating cortisol’s roles such as neurodevelopment in concert with dehydroepiandrosterone (sulfate) and lung maturation, or support cortisol action at times of low ambient cortisol. This mechanism may underlie the known association between cortisol, progesterone and CBG, and be relevant principally in the fetal circulation due to the high progesterone concentrations encountered.

Hormonal and Cytokine Blood Profile of Dairy Cows in the Early Gestation Period

Abstract—The results of the studies on the evaluation of changes in the hormonal and cytokine status of black-and-white Holstein cows (n = 25) during the period of embryogenesis at the physiological formation of pregnancy, intrauterine growth retardation, and embryonic demise are presented. The levels of progesterone, cortisol, interleukin IL-2, tumor necrosis factor TNFα, interferon-γ, and interferon-tau were determined in the dynamics of gestation in blood serum. It was found that, in case of embryogenetic disorder, the blood concentration of progesterone was lower than in animals with physiological course of pregnancy by 14.0–30.1%, cortisol by 17.8–35.2%, and interferon-tau by 22.0–37.7%, while IL-2 indexes were excessed by 46.5–31.0%, TNFα by 11.7–36.2%, and interferon-γ by 44.0–78.0%. The disturbance of the hormonal-cytokine balance in the organism of inseminated and fertilized animals is a universal pathogenesis of early embryopathies and is a key point at the clinical manifestation of these pathologies.

The use of progesterone during pregnancy in women with epilepsy as an alternative to the correction of doses of anticonvulsants

Pregnancy is the most dangerous period in terms of interruption of even persistent and long-term remission. At the same time increasing the dose of anticonvulsant increases the risk of teratogenic effects.
 Aim. to assess the possibility of using progesterone to prevent relapse of epileptic seizures during pregnancy.
 Materials and methods. 38 pregnant patients with epilepsy with clinical remission before pregnancy, with relapse of epileptic seizures in I trimester of pregnancy, age 31.81.4 years. Dydrogesterone in a dose of 10 to 60 mg/day was prescribed after the relapse of remission. Anticonvulsant dosage was not changed. The blood progesterone concentration and EEG control was carried out.
 Results. During pregnancy, the level of progesterone in the blood gradually increased from 77.8 nmol/l at 78 weeks of pregnancy to 521.1 nmol/l at 3637 weeks of pregnancy, without exceeding the limits. EEG results did not deteriorate. None of the patients had seizures during pregnancy.
 Conclusion. Progesterone therapy is an adequate and safe alternative to increasing the dose of anticonvulsants in case of recurrent seizures during pregnancy.

Clinical utility of plasma progesterone and blood and plasma glucose concentrations in predicting parturition in Holstein cows

An accurate, practical, and low-cost method for predicting parturition is urgently needed in the dairy industry. The objective of this study was to evaluate changes in plasma progesterone concentration ([prog]) and glucose concentration in whole blood ([gluc]b) and plasma ([gluc]p) as predictors of parturition within 6, 12, and 24 h in primiparous and multiparous Holstein cows. Blood samples were obtained daily at approximately 0900 h from 34 primiparous and 72 multiparous Holstein cows in late gestation and the time of calving recorded to the nearest hour. Plasma [prog] was measured using an ELISA, and [gluc]b and [gluc]p using a low-cost point-of-care glucose meter. The optimal cut-point for predicting parturition was determined using binomial logistic regression with general estimating equations, because the data set consisted of repeated measures for each cow. Diagnostic test performance was evaluated by comparing the area under the receiver operating characteristic curve (AUC) and calculating the sensitivity, specificity, and κ at the optimal cut-point for predicting parturition. Plasma [prog] was the most accurate predictor of parturition within 24 h (AUC = 0.96) and 12 h (AUC = 0.93), whereas [gluc]b was the most accurate predictor of parturition within 6 h (primiparous, AUC = 0.96; multiparous, AUC = 0.86). We conclude that a decrease in plasma [prog] is currently the most accurate test for predicting calving within 24 h. Measurement of [gluc]b is a promising new test for the cow-side prediction of parturition in dairy cows due to its accuracy, practicality, and low cost.

Physiologic responses to feeding rumen-protected glucose to lactating dairy cows

It was hypothesized that rumen-protected glucose (RPG) in diets of dairy cows increases concentrations of insulin resulting in greater blood progesterone concentrations because elevated insulin decreases activity of liver enzymes inactivating steroid hormones. Timing of ovulation was synchronized among 64 postpartum Holstein cows using GnRH and PGF2α (Day 0 = ovulation). Cows were milked thrice daily and assigned randomly a basal diet supplemented with 0, 1, 2, or 4 kg of an RPG product in place of corn grain, top-dressed in the diet beginning on Day -3. Blood was collected pre- and post-prandial on Days 0, 2, and 4 to determine plasma glucose and insulin concentrations and daily from Days 2 through 12. Intake of crude protein and energy-soluble carbohydrates increased linearly with dose, whereas starch intake decreased linearly with dose. Neither daily milk yield nor dry matter intake (DMI), energy-corrected milk (ECM), somatic cell count, or percentages of milk fat, protein and lactose on Day 8 differed among dietary treatments. Neither pre- nor post-prandial changes in plasma glucose differed among treatments. In contrast, post-prandial glucose decreased from Days 0 through 4. A change in plasma insulin (post-prandial minus pre-prandial) was detected. Milk urea nitrogen increased linearly with RPG dose. Concentrations of progesterone were unaffected by RPG dose. It is concluded that insulin response to RPG was decreased relative to the control and RPG supplementation linearly increased crude protein intake and milk urea nitrogen with increasing dose, but did not affect concentrations of progesterone, milk yield, or dry matter intake.

UTERINE FIBROIDS IMPACT ON FERTILITY AND PREGNANCY OUTCOME

The clinical confirmation of the relationship between uterine leiomyoma and female infertility is of interest to scholars. The aim of our research was to study obstetric history and the level of sex hormones in women of reproductive age with leiomyoma. Materials and methods. The main group consisted of 90 women of reproductive age with uterine leiomyoma, the control group - 45 healthy women. Gynaecological and obstetric history, hormone content in peripheral blood and pelvic vessels (estradiol, progesterone) were analysed. Statistical processing of clinical material was performed using Microsoft Excel, Statistica 7.0, and Statistica 8.0 for Windows. Results. The frequency of infertility in the surveyed women with LM was 18.9 %. One in three patients in the main group (33.3 %) did not give birth, which was statistically different from the healthy women group. In this case, 25.6 % of women in the main group did not use any methods of contraception. It was found that 51.11 % of patients with LM had threatened miscarriage in their history, 37.5 % – complicated delivery. Pathological changes in the concentrations of estradiol and progesterone in the preferential blood and blood vessels of women with fibroids have been identified. We have found that the content of sex hormones in the local bloodstream has a reliable relationship with the location of the myomatous node. Conclusion. The obtained results may indicate that leiomyoma contributes to the reduction of fertility. This is evidenced by the fact that women with LM are more likely to have the risk of miscarriage, complicated delivery and delivery by caesarean section, including complicated one. The findings have made a significant contribution to the further development of effective strategies for the prevention and treatment of infertility in women with fibrotic uterine lesions.

Parameters for Concentrations of Sows’ Gonadal Steroids in Predicting Inflammatory Processes in the Reproductive Tract

The objective of the survey is to reveal the effects of a dysfunctional relationship between the gonadal steroids (progesterone and 17β-estradiol) on occurrence of inflammatory diseases (endometriosis and metritis-mastitis-agalactia) in sows in the postpartum period. The surveys were carried out with 27 sows at 106–107 days of gestation, measuring the concentrations of progesterone and 17β-estradiol on the seventh, fifth, third, and first days before the expected farrowing date and during parturition. The subsequent retrospective analysis of the results of the collected measurements was performed depending on the course of the postpartum period in sows. It was ascertained that the progesterone blood concentrations the 3 days before the farrowing date and during parturition in sows affected with postpartum diseases were higher by 48.7 (p < 0.01) and 31.1% (p < 0.05), respectively, than that in the animals that remained healthy after farrowing, while the estradiol concentrations were lower by 10.1 and 21.0%, respectively. In addition, progesterone-to-estradiol ratio variables were 1.6-fold (p < 0.01) and 1.7-fold (p < 0.01) higher, respectively. This allows for the consideration that a dysfunctional relationship between the hormones in sows at the end of gestation and during parturition can be one of the factors causing the pathological processes of an inflammatory type in the postpartum period. In addition, it is eligible to apply the progesterone-to-estradiol ratio as a criterion for predicting the risk for disease incidence.

Effect of two postpartum intramuscular treatments with β-carotene (Carofertin®) on the blood concentration of β-carotene and on the reproductive performance parameters of dairy cows

The aim of the study was to determine whether two postpartum intramuscular treatments with 200 mg of beta-(β-)carotene (Carofertin; Alvetra u. Werfft, Vienna, Austria) in a 14-day interval increases β-carotene concentrations in blood, particularly around the time of the first artificial insemination (AI), and to test the effect of the treatment on fertility parameters, luteal size, and progesterone blood levels of dairy cows. A total of 297 Holstein dairy cows were enrolled in the study. Between 28 and 34 days postpartum (dpp) β-carotene concentrations were measured in blood samples using an on-site test (iCheck carotene; BioAnalyt, Teltow, Germany). Cows with a β-carotene concentration <3.5 mg/L, indicating a deficiency of β-carotene, were allocated either to the β-carotene treatment group BCT (n = 123) or to the control group CON (n = 121). Cows with concentrations ≥3.5 mg/L were assigned to an optimally supplied reference group (REF; n = 53). Cows in the BCT group received 200 mg of β-carotene intramuscularly at 28–34 dpp and at 42–48 dpp. Further blood samples were collected at 35–41 dpp, 42–48 dpp, 49–55 dpp, and in the week after the first AI and their β-carotene concentrations were analyzed. Between day 10 and 14 after the first AI, the blood progesterone concentration was measured and the size of the corpus luteum (CL) was determined by ultrasound. Blood β-carotene concentrations increased in the BCT cows in the week after the treatment with a peak at 49–55 dpp and were significantly higher than in the CON group at each time point after the first treatment. Logistic regression models, however, revealed that the treatment with β-carotene had no effect on first service conception rate, days to first service, time to pregnancy, or percentage of pregnant cows within 150 dpp. Furthermore, there was no effect on progesterone concentration or the size of the CL between the groups. In conclusion, two treatments with Carofertin postpartum increased β-carotene blood concentrations but had no effect on the fertility parameters in this study.

Secretion of equine chorionic gonadotropin and its association with supplementary corpus luteum formation and progesterone concentration in Hokkaido native pony recipient mares

The objectives of this study were to determine the plasma profile of equine chorionic gonadotropin (eCG) and its association with the formation of supplementary corpus luteum (CL) and plasma progesterone concentrations in embryo transfer Hokkaido native pony recipient mares. Blood samples and transrectal ultrasound examination of the reproductive tract were carried out weekly from the day of ovulation until week 32 of gestation (n = 4). Plasma concentrations of eCG and progesterone were measured by enzyme immunoassays. The eCG concentration was first detectable at week 5 for 2 mares and at week 6 for another 2 mares. Immediately after detection, the mean plasma eCG concentrations were observed to rise sharply and reach a peak at week 8. The concentrations then declined dramatically to a baseline (<0.5 IU/mL) by week 21. Plasma progesterone p=p concentrations increased in 2 phases. First, a sharp increase from 0.18 ± 0.05 ng/mL at ovulation to 15.9 ± 4.6 ng/mL at week 1 was observed, then a decrease to 9.69 ± 2.27 ng/mL by week 2, and maintained at this level until week 5 of gestation. The onset of the second rise occurred at week 6 and was observed to peak to 58.3 ± 21.8 ng/mL at week 10, then gradually declined to <10 ng/mL by week 26. The supplementary CLs were first detectable by pregnancy week 6 and 7 for 2 mares each. All supplementary and primary CLs regressed by week 26 for 3 mares and by week 30 for the remaining mare. The mean number of supplementary CL was 4.5 ± 0.8 and their formation in the right ovary (66.7%, 12/18) was higher (P < 0.05) than that in the left ovary (33.3%, 6/18). Among the mares, 1 mare that developed only 2 supplementary CL had 35% lower level of peak eCG and 65% lower concentration of peak progesterone compared with other 3 mares that had 5 or 6 supplementary CL. In conclusion, development of supplementary CL and blood concentrations of progesterone from around day 40 of gestation were associated with eCG concentration. The total number of supplementary CL formation in the present study in embryo transfer Hokkaido native pony recipient mares seemed higher than previously reported supplementary CL number in pregnant mares, with a greater rate in the right ovary than in left.

THE FEATURES OF THE HORMONAL HOMESOSTASIS OF PREGNANT GROUPS OF THE RISK OF DEVELOPMENT OF THE LATE MATURATION OF THE CERVIX BASED ON THE INTERGENETIC INTERVAL

The importance of the problem of prolonged pregnancy is due to a significant number of complications in childbirth, a high rate of surgical methods of delivery, which can further lead to a violation of the reproductive function of women, as well as high perinatal mortality.The purpose of the study. Determination of the peculiarities of hormonal homeostasis in women with late maturation of the cervix depending on the intergenetic interval.Materials and research methods. 156 women at risk of delayed cervical maturation after 41 weeks of pregnancy were examined. Women are divided into groups as follows: 1 group - first births (26 women); Group 2 - IGI was up to 3 years old (13 women); Group 3 - IGI from 3 to 5 years (57 women); Group 4 - IGI from 5 to 10 years (34 women); Group 5 - IGI for over 10 years (26 women).Results. The concentration of estradiol at 39–40 weeks of pregnancy in the bloodstream of 1 group reached the maximum value and stored (69.1 ± 1.1) nmol / L. Concentration of progesterone in blood at all times in women with physiological terminology of the canopy of the floor (769.9 ± 22.1) nmol / l, coefficient P / E2 - 10.7 ± 0.7. Women of the first and second groups had a timely maturation of the birth canal, which showed the prevalence of estrogenic effects on the vaginal epithelium and reduced inhibition of progesterone on target organs and tissues. There was an increase in the concentration of cortisol in the blood of pregnant women of group 5. At the same time, prolactin secretion was significantly decreased in pregnant women in groups 4 and 5 relative to those of women in group 1.Conclusions. In pregnant women with delayed maturation of the cervix, a decrease in the concentration of cortisol and a tendency to decrease prolactin. There is also a disruption of the function of the fetoplacental complex, represented by absolute and relative hypoestrogenia in the presence of serum progesterone concentration unchanged relative to the norm. In women with late maturation of the cervix, hyperandrogenism was not detected.

Luteal Blood Flow and progesterone concentration during first and second postpartum estrous cycle in lactating dairy cows

The aim of the present study was to determine the differences in corpus luteum (CL) functionality between the first postpartum estrous cycle and the following cycle in lactating dairy cows. Luteal blood flow (LBF), luteal size and blood progesterone (P4) concentration were monitored during the first and second postpartum estrous cycle. During the first and second postpartum estrous cycle, the mean LBF value increased (p<.05) from early to late dioestrus, while it decreased rapidly in proestrus, resulting statistically lower (p<.05) than those registered in all previous phases. Statistically significant differences were not observed between overall LBF during first and second postpartum estrous cycle (p>.05). During the first postpartum estrous cycle, P4 blood concentrations showed a significant reduction (p<.05) from dioestrus to proestrus. A different trend of P4 concentrations was observed during the second postpartum estrous cycle, where mean P4 value registered in proestrus resulted statistically lower than those registered in the previous cycle phases (p<.05). The mean P4 concentration registered over the first postpartum estrous cycle resulted statistically lower (p<.05) than that registered during the second one. A significant correlation between P4 concentrations and LBF was registered only during the second postpartum estrous cycle. Results indicate that during the first postpartum estrous cycle, P4 concentration was independent of luteal blood flow and luteal size.

Control and induction of ovulation in cattle

The control and induction of ovulation in cattle are discussed with particular reference to use of progesterone-impregnated coils in heifers and beef cows. Progesterone treatment for 14 days was required to obtain precise onset of oestrus. With 7, 9 or 12 days of progesterone treatment a luteolytic agent in the form of a prostaglandin (PG) or oestradiol benzoate had to be used. Fertility was normal after treatment durations of 7, 9 or 12 days, but fertility after 14-day treatment requires further testing. The progesterone coil was not effective in maintaining luteal-phase levels of progesterone throughout a 12-day treatment and increasing the concentration of progesterone in the coil from 4 to 20% was not effective in elevating the progesterone concentrations in blood. When progesterone concentrations dropped below approximately 1.5 ng/ml the basal level of LH began to rise before removal of the coil. A 2-fold rise in the basal level of LH was observed following the removal of the progesterone coil. This early rise in LH was absent in cows which did not ovulate after they were given a 12-day progesterone treatment and GnRH 24-36 h after removal of coils to induce the main LH peak. Absence of this early rise suggests that frequency and amplitude of episodic LH release were inadequate in the post-partum anovulatory period. Ovariectomy in the early post-partum period was not followed by an abrupt LH release.

Reproduction in female South American domestic camelids

Alpacas and llamas are induced ovulators. They show marked reproductive seasonality in the Andean region, but under Northern Hemisphere conditions of feeding and management, they are non-seasonal breeders. Puberty is attained when they reach 50% of adult body weight. When they are not exposed to a male, females show successive waves of follicular maturation and atresia. Growth, maintenance and regression of a follicle each require an average of 4 and 6 days in alpacas and llamas, respectively. After sterile mating, progesterone concentrations in blood were increased from day 5, reached maximum concentrations on day 7-8, and declined rapidly at 9-10 days after mating. A fertile mating results in formation of a corpus luteum that remains functional throughout gestation. The duration of gestation is 340-346 days. Almost all fetuses were found to occupy the left uterine horn, even though ovulation occurs from both ovaries with equal frequency. Several methods of pregnancy diagnosis have been described. Mating is recommended within 15-20 days after parturition to obtain good fertility rates and one offspring per year. The factors that contribute to high rates of embryonic mortality are unknown. Reproductive technologies, such as AI, superovulation, embryo transfer and IVF, have not been used very extensively in these species but can be successfully applied.

Evaluating reproductive performance of three estrus synchronization protocols in Ghezel ewes

Although estrus synchronization considered valuable management tools for improving reproductive performance of ewes, their high expenses and complicated usage prevent sheep farmers to apply these techniques. Therefore, the present study was designed to compare three protocols of estrus synchronization on reproductive performance of Ghezel ewes. For this reason, 27 Ghezel ewes were assigned to three estrus synchronization treatment groups based on a completely randomized design included: progestogen sponge for 12 days + 500 IU eCG at the time of sponge withdrawal (P4eCG group, expensive synchronization), two doses of 75 μg cloprostenol with 12 days interval (CLO group, economical synchronization), and CLO +500 IU eCG at day 12 (CLOeCG group, moderately priced synchronization). Four consecutive blood samples were also collected during the experiment to evaluate progesterone concentrations. The results of the present experiment showed that pregnancy and lambing rates of the first estrus as well as blood progesterone concentration were not affected by the treatments (P > 0.05), though total pregnancy and lambing rates were higher in both P4eCG and CLOeCG groups (P < 0.01). Accordingly, both P4eCG and CLOeCG protocols successfully improved reproductive traits of ewes, though CLOeCG protocol is an advisable technique for sheep farmers through its moderate price, simple application, and high reproductive performance.

Embryonic development, luteal size and blood flow area, and concentrations of PGF2α metabolite in dairy cows fed a diet enriched in polysaturated or polyunsaturated fatty acid

The objective of this study was to examine effects of sunflower (SO) and palm oil (PO) supplements in the diet on embryonic development, luteal size and blood flow area, PGF2α metabolite (PGFM), and progesterone (P4) concentrations. Prepartum cows (n = 42) were randomly assigned to one of three dietary treatments (control, 4% PO, and 4% SO supplements). Animals were fed diets individually from day 28 prepartum to day 111 postpartum. Luteal size and blood flow area were determined throughout the estrous cycle by Doppler ultrasonography. Oocytes were collected in three ovum pick-up sessions at 2 week intervals for the in vitro embryo production. Oocyte characteristics and embryonic development were not affected by dietary treatments. Cows fed 4% SO had a greater (P < 0.05) concentration of PGFM from day 15 to day 35 postpartum than those cows fed 4% PO and the control group. On day 11 of the estrous cycle (mid-luteal phase), serum P4 concentrations (6.0 ± 0.7, 5.7 ± 0.5, and 4.7 ± 0.6 ng/ml), luteal size (7.0 ± 0.2, 6.5 ± 0.2, and 5.3 ± 0.1 cm2) and luteal blood flow area (1.3 ± 0.2, 1.2 ± 0.1, and 0.9 ± 0.1 cm2) were greater (P < 0.05) in cows fed 4% SO and 4% PO than the control group, respectively. Thus, plant oil supplements in diets affected luteal size and serum P4 and PGFM concentrations, but not early embryonic development. Such changes in secretion of PGF2α and P4 indicate that plant oil supplements during pre- and postpartum may alter uterine and luteal functions.

Kisspeptin and bovine follicular cysts.

The aim of this study was to investigate kisspeptin (Kp) and sexual hormone blood concentrations in healthy dairy cows (H) and in cows diagnosed with ovarian follicular cysts (FC). Forty dairy cows were enrolled in this study and divided in 2 groups of 20 subjects each. All cows underwent blood collection on the day of diagnosis and on that of heat detection, respectively. Kisspeptin 10, estradiol, and progesterone blood concentrations were assessed. All the parameters were higher in Group FC than in Group H. These results suggest that the higher steroid levels found may have determined the increase in Kp secretion in the cystic cows. This, in turn, may have directly or indirectly stimulated the sustained Luteinizing Hormone (LH) release, known to occur in dairy cystic disease.

Blood periovulatory progesterone quantification using different techniques in the dog

Blood progesterone concentration is used in several procedures related to the reproduction in the bitch, such as ovulation monitoring, estimating time of parturition, or hypo-luteoidism management. Several techniques are available to evaluate blood progesterone concentration, such as the radioimmunoassay (RIA), the chemiluminescent immunoassay (CLIA), and the enzyme-linked immunosorbent assay (ELISA). The aim of this study was to compare the blood progesterone concentration using these three methods during the periovulatory period of 23 bitches. Vaginal cytology was used to classify cytologic estrus (CE) and cytologic diestrus (CD), and blood samples were collected once during proestrus and every other day between CE and CD. The samples were retrospectively classified in the different phases of the estrus based on CD. Pregnancy rate and gestational length were also recorded. A significant increase of the circulating progesterone during the progression of the estrus was recorded, and there were significant differences in the values when using the different methods, with lesser, intermediate, and greatest values with use of the RIA, CLIA, and ELISA, respectively. There was a high correlation (Pearson’s correlation coefficient = 0.978) and substantial strength-of-agreement (Lin’s concordance correlation coefficient = 0.966) between values obtained when using CLIA and RIA, while there was a high correlation (Pearson’s correlation coefficient = 0.955) but poor strength-of-agreement (Lin’s concordance correlation coefficient = 0.866) with use of the ELISA and RIA. The data reported in this study provide evidence that the method used for measuring the blood progesterone concentration during the periovulatory phase of the bitch significantly affected the progesterone values.

Effects of long-term, near-term, and real-time energy balance, and blood progesterone concentrations, on the pregnancy rate of contemporary dairy cows

This study aimed to contribute to understanding the interface between reproductive and nutritional energetic physiology in contemporary dairy cattle. Multiparous Holstein cows (n = 32) between 70 and 180 days in milk were used in a study starting 10 d prior to the artificial insemination (AI) date and were estrous synchronized using a hormonal regimen. Fourteen cows were determined pregnant on day 39 post-AI. Coccygeal blood samples of all cows were collected on d −10 and −3 prior to AI to determine estrous cyclicity, as well as at AI and at 6, 13 and 20 d post-AI. Milk progesterone was measured 20 d post-AI, and body condition was scored (BCS; 1–5 scale) on days −10, 0, 13 and 27 relative to AI. Blood non-esterified fatty acid concentrations, measured on the same days as BCS, and changes of BCS from d −10 to AI were not predictive of pregnancy outcome. The BCS of cows on the day of AI was greater (P = 0.02) for pregnant cows with an approximate minimum BCS for a high probability of conception being 2.50. Serum progesterone concentrations of pregnant cows were greater (P < 0.05) on days 6, 13 and 20 post-AI, as was milk progesterone at day 20 post-AI (P < 0.01). Pregnant cows had greater (P = 0.02) net energy output (NEL), which is inconsistent with a common belief that low pregnancy rates in contemporary dairy cows are due to excessive milk production, but is consistent with published studies in this study area. The present research indicates that current low pregnancy rates in commercial high-producing multiparous dairy cattle may be partly due to breeding cows that have insufficient BCS to support pregnancy.