Conception Rate Research Articles

A large population study to assess the magnitude of prenatal programming in dairy cattle

The performance of an adult dairy cow may be influenced by events that occur before her birth. The present study investigated potential effects of 2 prenatal groups of factors, Assisted Reproductive Techniques (ART) and maternal characteristics (e.g., dam parity), on offspring performance during their first lactation, in populations of 2 dairy cow breeds: French Holstein and Montbéliarde. The different ART studied included the type of semen (conventional or X-sorted) used for Artificial Insemination (AI) and the technology of conception used (AI, embryo transfer, or in vitro fertilization). Three maternal characteristics were considered: (1) the dam age at first calving, (2) dam parity number, and (3) indicators of dam udder health during gestation (somatic cell score and events of clinical mastitis). First, we investigated whether heifer survival from 3d to 18 mo old was associated with any of the prenatal factors considered. We then estimated the associations of these prenatal factors with 8 traits of commercial interest: (1) stature, (2-4) milk, fat, and protein yields, (5) somatic cell score, (6) clinical mastitis, and (7-8) heifer and cow conception rate, all measured on genotyped cows. Linear models were used for this study with the prenatal factors as covariates in the model, and for the 8 traits, phenotypes were adjusted for their corresponding genomic estimated breeding value. The results indicated that the survival rate of heifers born from embryo transfer was significantly higher than that of heifers born from AI (probably due to preferential management practices), while the other prenatal factors did not explain differences in heifer survival. Among the Montbéliarde cows born from AI, those born from X-sorted semen showed a lightly but significantly lower milk yield than those born without X-sorting of the semen (-52 kg of milk in the first lactation). Among the Holstein cows, those born from embryo transfer presented significantly lower milk performance than cows born from AI. Regarding the maternal characteristics, none or very weak associations were found between the dam age at first calving and the offspring performance in both breeds. Dam parity, on the other hand, was associated with offspring performance for milk, fat, and protein yield in both breeds, however not in the same direction. In the Holstein breed, an increase in dam parity was favorable for offspring performance for milk, fat, and protein yield, whereas in the Montbéliarde breed, an increase in dam parity was associated with lower milk and protein yield and no association was found for fat yield. The udder health of the dam during gestation was not or only weakly associated with the traits studied in the offspring. Although some significant associations were identified due to the large sample size, the effects were modest, typically less than 1% of the phenotypic mean, and were not consistently observed across the 2 breeds.

Evaluation and Comparison of Therapeutic Efficacy of Various Hormonal Protocols in Anoestrus Buffalo Heifers of Semi-Arid Region

To assess and compare different hormonal protocols' treatment efficacy in anoestrus buffalo heifers in a semi-arid region. Forty buffalo heifers with a history of anoestrus were chosen randomly from the semi-arid region of Banaskanth and divided into four equal groups.Group-I: Heatsynch protocol (n = 10), Group-II Ovsynch protocol (n = 10), Group-III Doublesynch protocol (n = 10) and Group-IV Control (n = 10) are followed by artificial insemination at a predetermined period in treated buffalo heifers and insemination during spontaneous estrus in group-IV buffalo heifers. In Groups I, II, and III, the corresponding percentages of estrus induction were 90, 80, and 80 percent. Major symptoms such as edoema, erythema, dampness of vulva and estrus mucus secretion were present during the expression of estrus. Fifty percent of the buffalo heifers in Group IV displayed estrus at varying intervals. After three consecution services, Group II had the highest overall fertility rate (50%) followed by Group III (40%), Group I (30%), and Group IV (30%). In true anoestrus buffalo heifers, the Heatsynch, Ovsynch, and Doublesynch procedure can be applied with success to induce estrus. Buffalo heifers that follow the Ovsynch protocol may have a higher conception rate.

Conception rates of cows inseminated with frozen semen of Rural Development Academy, Bogura, Bangladesh

Background: The first service conception rate (FSCR) is an important parameter for any artificial insemination (AI) programme. The present study was conducted to determine the FSCR and its influencing factors in cows inseminated with frozen semen produced by Rural Development Academy, Bogura. Methods: Data were collected from 372 cows at 39 villages under Sherpur Upazilla of Bogura district on breed, age, body condition score (BCS), parity, milk yield, suckling, AI season and the interval between oestrus to AI using a questionnaire. Results: The overall FSCR of cows was 66.4% and the service per conception was 1.53. The FSCR was higher (74.1%) in local cows compared to the Holstein-Friesian (HF) cross counterpart (64.2%). The FSCR was higher (70.4%) in 24-47 months old cows compared to 84-98 months old counterpart (61.5%). The highest FSCR (81.6%) was observed in cows with 3.0 to 3.5 BCS and the lowest (25.7%) was observed in cows with 2.5 BCS. The highest FSCR (68.3%) was observed in the 0 (zero) parity (heifers) group of cows and the lowest (62.5%) was observed in the 4-7 parity counterpart. The highest FSCR (72.4%) was observed in cows yielded daily >15-22 L milk and the lowest (62.1%) was observed in cows yielded ≤5 L milk. The highest FSCR (72.7%) was observed in suckling restricted cows and the lowest (60.9%) was observed in cows that had several times suckling daily. The highest FSCR (72.1%) was observed in cows received inseminations in Rainy (July-October) season and the lowest (58.4%) was observed in cows received inseminations in Winter (November-February). The highest FSCR (67.1%) was observed in cows received inseminations between 12-18 hrs of detection of oestrus and the lowest (59.1%) was observed in cows received insemination between 8-11 hrs of detection of oestrus. However, the difference in FSCR in cows with different BCS groups was significant (p<0.01). Conclusion: The current FSCR in cows can be considered to be satisfactory. The BCS of cows significantly influences the FSCR in cows.

Blood Plasma Biochemical Changes and Conception Rate in Anoestrus Buffaloes Treated with Various Hormone Protocols

To study certain blood biochemical parameters (total cholesterol, total protein, calcium and inorganic phosphorus) at various periods of treatment. Total 40 anestrous buffalo heifers with history of anoestrus were selected from the semi-arid area of Banaskanth and randomly divided into four equal groups. (1)Group-I:Heatsynch protocol (n=10), (2)Group-II:Ovsynch protocol(n=10), (3)Group-III: Doublesynch protocol (n=10) and (4)Group-IV: Control(n=10) followed by fixed time artificial insemination in treated buffalo heifers and insemination at spontaneous estrus in buffalo heifers of group-IV. The overall conception rate following 3 consecution services was maximum in Group II (50%) followed by Group III (40%), Group I (30%) and Group IV (30%). The blood plasma was collected at the time of initiation of treatment (P1), at the time of inj. PGF2α (P2), at the time of 1st FTAI (P3) and day 21st post insemination (P4) for the estimation of biochemical parameters. The blood biochemical profiles include total protein (range: 4.54± 0.19 to 6.11± 0.52 g/dl) which in all group did not show any significant difference during the different period but significant (P<0.05) difference between the groups was noticed. Similarly calcium and phosphorus found ranging between 5.73± 0.20 to 9.53± 0.95 mg/dl and 5.46± 0.22 to 6.95± 0.30 mg/dl, respectively in all four groups. The cholesterol estimated values (range: 34.12 ± 1.75 to 41.97± 2.43 mg/dl) were found not-significantly varying between the groups as well as among the different periods. Heatsynch, Ovsynch and Doublesynch protocol can be successfully used for the induction of estrus in true anoestrus buffalo heifers with Better conception rate would be achieved following Ovsynch protocol in buffalo heifers.

Effect of High Energy Diet Supplementation during Periparturient Period on Ovarian Steroids and Reproductive Performance in Vrindavani Cows

The objective of the study was to assess the effect of high energy diet supplementation during periparturient period on ovarian steroids and reproductive performance in vrindavani cows. Postpartum vrindavani cows (n= 20) of second to fourth parity with lactation yield of > 10 L/day were divided in to two groups (n=10 cow/group). Group I (CON) cows were fed with basal diet to serve as control. Group II (TRT) cows were provided with 20% extra concentrates in the form of energy. 20% additional concentrate diet was supplemented from second week to eight week after calving. Blood samples were collected at weekly interval from 4 week before calving to8weeks after calving. Blood samples were collected to determine estradiol (E2) and progesterone (P4) in the serum using RIA. Postpartum reproductive performance was assessed in terms occurrence of first postpartum estrus, calving to conception interval, conception rate and number of service per conception. Serum estradiol and progesterone concentration increased significantly(P<0.05) from 2 to 8 week postpartum in Group II as compared to Group I. Marked significant(P<0.05)improvement in the postpartum reproductive performance in terms of early occurrence of first postpartum estrus(67.0Vs 53.0), reduced calving to conception interval(85.87 Vs74.4), service per conception (1.62 Vs 1.2), days from calving to first AI(88.5 Vs 65.73), higher first AI conception rate(40 Vs 80%) and cumulative conception rate(88.52 Vs 65.73%) in group II as compared to group I. In conclusion, additional high energy diet supplemented group showed significant increased ovarian steroid hormonal concentrations and marked improvement in the reproductive performance in Vrindavani cows.

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.

Genomic prediction of male fertility in Brown Swiss cattle

Bull fertility has been recognized as an important factor affecting dairy herd fertility. The objective of this study was to assess the feasibility of predicting male fertility in Brown Swiss cattle using genomic data. The data set consisted of 1,102 Italian Brown Swiss bulls with sire conception rate (SCR) records and genotype data for roughly 480k SNP. The analyses included the use of linear kernel-based regression models fitting all SNPs or incorporating markers with large effect. Predictive performance was evaluated in 5-fold cross-validation using the correlation between observed and predicted SCR values and mean squared error of prediction. The entire SNP set exhibited predictive correlations around 0.19. Interestingly, the inclusion of 2 markers with large effect yielded predictive correlations around 0.32. Overall, using linear kernel-based models fitting markers with large effect is a promising approach. Our findings could help Brown Swiss breeders make enhanced genome-guided management and selection decisions on male fertility.

Effect of temperature-humidity index on the evolution of trade-offs between fertility and production in dairy cattle

BackgroundIn the current context of climate change, livestock production faces many challenges to improve the sustainability of systems. Dairy farming, in particular, must find ways to select animals that will be able to achieve sufficient overall production while maintaining their reproductive ability in environments with increasing temperatures. With future forecasted climate conditions in mind, this study used data from Holstein and Montbeliarde dairy cattle to: (1) estimate the genetic-by-temperature-humidity index (THI) interactions for female fertility, and (2) evaluate the production-fertility trade-off with increasing values of THI.ResultsTwo-trait random regression models were fitted for conception rate (fertility) and test-day protein yield (production). For fertility, genetic correlations between different THI values were generally above 0.75, suggesting weak genotype-by-THI interactions for conception rate in both breeds. However, the genetic correlations between the conception rate breeding values at the current average THI (THI = 50, corresponding to a 24-h average temperature of 8 °C at 50% relative humidity) and their slopes (i.e., potential reranking) for heat stress scenarios (THI > 70), were different for each breed. For Montbeliarde, this correlation tended to be positive (i.e., overall the best reproducers are less affected by heat stress), whereas for Holstein it was approximately zero. Finally, our results indicated a weak antagonism between production and fertility, although for Montbeliarde this antagonism intensified with increasing THI.ConclusionsWithin the range of weather conditions studied, increasing temperatures are not expected to exacerbate the fertility-production trade-off. However, our results indicated that the animals with the best breeding values for production today will be the most affected by temperature increases, both in terms of fertility and production. Nonetheless, these animals should remain among the most productive ones during heat waves. For Montbeliarde, the current selection program for fertility seems to be adequate for ensuring the adaptation of fertility traits to temperature increases, without adverse effects on production. Such a conclusion cannot be drawn for Holstein. In the future, the incorporation of a heat tolerance index into dairy cattle breeding programs would be valuable to promote the selection of animals adapted to future climate conditions.

Milk urea nitrogen is genetically associated with production and reproduction performance of dairy cows: A meta-analysis

This study aimed to conduct a meta-analysis using the random-effects model to integrate published estimates of genetic parameters for milk urea (MU) and milk urea nitrogen (MUN). The study used a total of 49 heritability and 147 genetic correlation estimates from 30 papers published between 2003 and 2023. The heritability estimates for MU and MUN were low and equal to 0.202 and 0.181, respectively. The genetic correlation estimates between MU and production traits were low and ranged from -0.039 (between MU and milk lactose percentage) to 0.102 (between MU and milk protein yield), but the genetic correlation estimates between MUN and production traits were low and varied from -0.070 (between MUN and somatic cell score) to 0.357 (between MUN and milk protein yield). The genetic correlation estimates between MUN and calving to first service, days open, and first service conception rate were low and equal to 0.093, 0.329, and 0.069, respectively. The results of present study showed that available additive genetic variation in MU and MUN could potentially be exploited in dairy cow genetic selection schemes. Although the correlations of MU and MUN with production and reproduction traits were low, there were some cases where they were unfavorable, and they should not be neglected when planning selection programs.

Fertility Responses to the COVID‐19 Pandemic: A Perspective of Reproductive Process

AbstractThe COVID‐19 pandemic has potential large‐scale impacts on population dynamics. Yet, recent theories and empirical analyses fall short of fully articulating the extent and nature of the pandemic's influence on birth rates at the aggregate level. This study advances the comprehension of fertility dynamics amid the pandemic by focusing on the reproductive process. The effects of the pandemic on conceptions and pregnancy terminations may exhibit considerable variability, which, in turn, could dictate the observed patterns in birth rates during the pandemic. Employing the data from the Performance Monitoring Action survey in Burkina Faso and Kenya, which includes information on conceptions, pregnancy terminations, and births, the research dissects the nuances of fertility behavior in response to the pandemic. Findings indicate an uptick in conception rates around six months following the onset of the pandemic in Kenya, while pregnancy terminations did not significantly shift in either country. Further, the data reveal a pronounced increase in conception rates among disadvantaged groups, whereas a downturn in pregnancy terminations was noted predominantly in urban areas during the early phase of the pandemic. These findings underscore the importance of considering the reproductive process when studying fertility responses to catastrophic events.

Estimation of genetic parameters for bull conception rate and its genetic correlations with semen production traits in Japanese Black bulls

The P of achieving pregnancy is an important trait of bull fertility in beef cattle and is defined as the bull conception rate (BCR). This study aimed to clarify and better understand the genetic architecture of the BCR calculated using artificial insemination and pregnancy diagnosis records from a progeny testing program in Japanese Black bulls. In this study, we estimated the genetic parameters of the BCR and their correlation with semen production traits. In addition, we assessed the correlated responses in BCR by considering the selection of semen production traits. Nine hundred and sixteen Japanese Black bulls were selected based on fertility, with 28 869 pregnancy diagnostic records from the progeny testing program. Our results showed that the heritability estimate was 0.04 in the BCR at the first service and 0.14 in BCR for the three services, and an increase in the inbreeding coefficient led to a significant decrease in BCR. The phenotypic trend of BCR remained almost constant over the years, whereas the genetic trend increased. In addition, the changes in the progeny testing year effect showed a similar tendency to the phenotypic trends, suggesting that the phenotypic trends could be mainly due to non-genetic effects, including progeny testing year effects. The estimated genetic correlation of BCR with sperm motility traits was favorably moderate to high (ranging from 0.49 to 0.97), and those with sperm quantity traits such as semen volume were favorably low to moderate (ranging from 0.23 to 0.51). In addition, the correlated responses in BCR at the first service by selection for sperm motility traits resulted in a higher genetic gain than direct selection. This study provides new insights into the genetic factors affecting BCR and the possibility of implementing genetic selection to improve BCR by selecting sperm motility traits in Japanese Black bulls.

Semen sexing and its impact on fertility and genetic gain in cattle.

Semen sexing is among one of the most remarkable inventions of the past few decades in the field of reproductive biotechnology. The urge to produce offspring of a desired sex has remained since traditional times. Researchers have tried many methods for accurate semen sexing, but only the flow cytometry method has proved to be effective for commercial utilization. However, there were always concerns about the effects of sexed semen, especially on fertility and the rate of genetic gain. Some concerns were genuine because of factors such as low semen dosage in sexed semen straws and damage to sperm during the sorting process. Various researchers have conducted numerous studies to find out the effect of sexed semen on fertility and, in this article, we reflect on their findings. Initially, there were comparatively much lower conception rates (∼70% of conventional semen) but, with refinement in technology, this gap is bridging and the use of sexed semen will increase over time. Concerning genetic gain with use of sexed semen, a positive effect on rate of genetic progress with the use of sexed semen has been observed based on various simulation studies, although there has been a mild increase in inbreeding.

Resumption of ovulation in anovulatory women with PCOS and obesity is associated with reduction of 11β-hydroxyandrostenedione concentrations.

Is resumption of ovulation after a 6-month lifestyle intervention in women with PCOS and obesity associated with differential changes in endocrine and metabolic parameters (weight, insulin resistance, anti-Müllerian hormone (AMH), and androgens) compared to women with PCOS who remained anovulatory? Resumption of ovulation after a 6-month lifestyle intervention in women with PCOS and obesity is associated with changes in serum 11β-hydroxyandrostenedione (11OHA4) concentrations. Lifestyle interventions have been shown to reduce clinical and biochemical hyperandrogenism in women with PCOS. Weight loss of 5-10% may reverse anovulatory status, thereby increasing natural conception rates. However, the mechanisms underlying why some women with PCOS remain anovulatory and others resume ovulation after weight loss are unclear. Reproductive characteristics at baseline and a greater degree of change in endocrine and metabolic features with lifestyle intervention may be crucial for ovulatory response. We used data and samples originating from an earlier randomized controlled trial (RCT), which examined the efficacy of a 6-month lifestyle intervention prior to infertility treatment compared to prompt infertility treatment on live birth rate in women with obesity. A total of 577 women with obesity (BMI > 29 kg/m2) were randomized between 2009 and 2012. Anovulatory women with PCOS who were allocated to the intervention arm of the original RCT (n = 95) were included in the current analysis. We defined women as having resumed ovulation (RO+) based on the following criteria: spontaneous pregnancy; or assignment to expectant management; or IUI in natural cycles as the treatment strategy after lifestyle intervention. Steroid hormones were measured using liquid chromatography tandem mass spectrometry. Generalized estimating equations with adjustment for baseline measures and interaction between group and time was used to examine differences in changes of endocrine and metabolic parameters between RO+ (n = 34) and persistently anovulatory women (RO-, n = 61) at 3 and 6 months after intervention. At baseline, the mean ± SD age was 27.5 ± 3.6 years in the RO+ group and 27.9 ± 4.1 years in the RO- group (P = 0.65), and the mean ± SD weights were 101.2 ± 9.5 kg and 105.0 ± 14.6 kg, respectively (P = 0.13). Baseline AMH concentrations showed significant differences between RO+ and RO- women (median and interquartile range [IQR] 4.7 [3.2; 8.3] versus 7.2 [5.3; 10.8] ng/ml, respectively). Baseline androgen concentrations did not differ between the two groups. During and after lifestyle intervention, both groups showed weight loss; changes in 11OHA4 were significantly different between the RO+ and RO groups (P-value for interaction = 0.03). There was a similar trend for SHBG (interaction P-value = 0.07), and DHEA-S (interaction P-value = 0.06), with the most pronounced differences observed in the first 3 months. Other parameters, such as AMH and FAI, decreased over time but with no difference between the groups. No high-resolution transvaginal ultrasonography was used to confirm ovulatory status at the end of the lifestyle program. The small sample size may limit the robustness of the results. Reduction of androgen concentrations during and after lifestyle intervention is associated with recovery of ovulatory cycles. If our results are confirmed in other studies, androgen concentrations could be monitored during lifestyle intervention to provide individualized recommendations on the timing of resumption of ovulation in anovulatory women with PCOS and obesity. The study was supported by a grant from ZonMw, the Dutch Organization for Health Research and Development (50-50110-96-518). The Department of Obstetrics and Gynecology of the UMCG received an unrestricted educational grant from Ferring Pharmaceuticals BV, The Netherlands. A.H. reports consultancy for the development and implementation of a lifestyle App MyFertiCoach developed by Ferring Pharmaceutical Company. All other authors have no conflicts to declare. The LIFEstyle RCT was registered at the Dutch trial registry (NTR 1530).

Intrauterine injection of bioengineered hydrogel loaded exosomes derived from HUCM stem cells and spermidine prominently augments the pregnancy rate in thin endometrium rats

The endometrium is essential to the development of embryos and pregnancy. Human umbilical cord mesenchymal stem cells (HUCMSCs) are promising stem cell sources. HUCMSCs self-renew quickly and are painless to collect. Spermidine is an inherent polyamine needed for cellular and molecular processes that regulate physiology and function. HUCMSCs and spermidine (SN) may heal intrauterine adhesions. HUCMSCs were investigated for endometrial repair in rats. Composite hydrogels are used for medical exosome implantation, including their materials, properties, and embedding procedures. This study examined whether bioengineered hydrogel-loaded exosomes from HUCMSCs and spermidine prenatally improved conception rates in mice with poor endometrial lining. The data show that HUCMSC and SN provide a good experimental base for HUCMSC safety and intrauterine treatment in rats. Western blots, exosome structural analysis, pregnancy outcomes, flow cytometry, H&E staining, immunohistochemistry, and immunofluorescence labelling found and recovered the aberrant area. HUCM-derived stem cells and spermidine-derived exosomes biophysically match. These traits strengthen and prolong endometrial function. Pregnant rats with HUCMSC and SN had thinner endometrium. Hydrogel-incorporated HEHUCMSC and SN exosomes may improve IUI in rats with thin endometrium.

Multimodal learning system integrating electronic medical records and hysteroscopic images for reproductive outcome prediction and risk stratification of endometrial injury: a multicenter diagnostic study.

To develop a multimodal learning application system that integrates electronic medical records (EMR) and hysteroscopic images for reproductive outcome prediction and risk stratification of patients with intrauterine adhesions (IUAs) resulting from endometrial injuries. EMR and 5014 revisited hysteroscopic images of 753 post hysteroscopic adhesiolysis patients from the multicenter IUA database we established were randomly allocated to training, validation, and test datasets. The respective datasets were used for model development, tuning, and testing of the multimodal learning application. MobilenetV3 was employed for image feature extraction, and XGBoost for EMR and image feature ensemble learning. The performance of the application was compared against the single-modal approaches (EMR or hysteroscopic images), DeepSurv and ElasticNet models, along with the clinical scoring systems. The primary outcome was the 1-year conception prediction accuracy, and the secondary outcome was the assisted reproductive technology (ART) benefit ratio after risk stratification. The multimodal learning system exhibited superior performance in predicting conception within 1-year, achieving areas under the curves of 0.967 (95% CI: 0.950-0.985), 0.936 (95% CI: 0.883-0.989), and 0.965 (95% CI: 0.935-0.994) in the training, validation, and test datasets, respectively, surpassing single-modal approaches, other models and clinical scoring systems (all P<0.05). The application of the model operated seamlessly on the hysteroscopic platform, with an average analysis time of 3.7±0.8s per patient. By employing the application's conception probability-based risk stratification, mid-high-risk patients demonstrated a significant ART benefit (odds ratio=6, 95% CI: 1.27-27.8, P=0.02), while low-risk patients exhibited good natural conception potential, with no significant increase in conception rates from ART treatment (P=1). The multimodal learning system using hysteroscopic images and EMR demonstrates promise in accurately predicting the natural conception of patients with IUAs and providing effective postoperative stratification, potentially contributing to ART triage after IUA procedures.

Conception rate according to the size and location of corpus luteum and coexistent follicle before embryo transfer in Hanwoo

Conception rate according to the size and location of corpus luteum and coexistent follicle before embryo transfer in Hanwoo

82 Effects of a red-clover containing mineral on heifer behavior and fertility

Abstract Heat stress reduces reproductive efficiency in beef cattle. Recent evidence suggests that supplementation of red clover can alleviate the physiological impacts of fescue toxicosis which could decrease heat stress. Our objective was to determine the effect of supplementing heifers grazing endophyte-infected tall fescue (E+ TF) with a conventional mineral containing red-clover leaf. We hypothesized that heifers supplemented with the red-clover leaf mineral would have greater conception rates to AI (CRAI) in times of possible heat stress compared with heifers supplemented with conventional mineral. A grazing study was conducted from May – August in 2021, 2022, and 2023. Yearling beef heifers (n = 32, 36, 40 heifers yr-1, respectively) were blocked by body weight, hair coat score and color into 4 grazing blocks that were assigned to 1 of 2 treatments (2 blocks treatment-1): 1. conventional non-medicated loose mineral control (0%-RC), or 2. conventional loose mineral + 20% wt/wt red clover leaf (20%-RC). Mineral treatments were provided in ground, 3-compartment mineral feeders ad libitum. Each grazing block was assigned to four, 0.8- ha. pastures consisting of predominantly E+ TF and were rotationally managed over the course of the study. Each year estrus was synchronized suitable for fixed time AI in May and all heifers resynchronized in June. In addition, each heifer was fitted with an ear-tag sensor (CowManager SensOor, Agis Automatisering BV, Harmelen, the Netherlands) for continuous behavioral monitoring (including high activity and activity). The CRAI were analyzed with the GLIMMIX procedure of SAS using the binomial distribution link logit function (v.9.4., SAS Inst. Inc., Cary, NC). Total daily activity and high activity reported by CowManger during May and June were analyzed by the MIXED procedure with repeated measures of SAS. The CRAI were similar for 20%-RC (67.30 ± 9.80%) and 0%-RC (60.70 ± 9.80%) heifers following the first service of AI (P = 0.51) during a thermoneutral period in May. In contrast, CRAI was greater (P = 0.02) for 20%-RC heifers (48.67 ± 13.47%) than CM (15.10 ± 13.47%) in June when temperatures increased to potential heat stress levels. Overall, conception rate after two rounds of AI for 20%-RC (78.30 ± 9.30%) heifers tended to be greater (P = 0.08) than CM (62.20 ± 9.30 %). While high activity (associated with estrous behavior) reported by CowManager did not differ between treatments (20%-RC: 203.94; 0%-RC: 213.90; SEM: 8.65 min d-1; P = 0.25), normal daily activity of 20%-RC heifers (150.69 ± 10.40 min d-1) tended to be greater (P = 0.06) than CM (126.33 ± 8.65 min d-1). Results of this study suggest supplementing red-clover containing mineral may mitigate negative effects of consuming E+ TF including decreased conception rates during times of heat stress.

115 Solubility and degradation of human fertility-promoting molecules in a rumen environment

Abstract Endometrial epithelial of cows conceiving was associated to gene set enrichment of pathways associated to synthesis, metabolism, and degradation of myo-inositol pathways (Physiol. Genomics 54: 71-85, 2022). Progesterone-modulated transcription also indicated an increase in oxidative phosphorylation pathways in the endometrial epithelial of cows. Thus, modulation of myo-inositol and oxidative phosphorylation pathways can favor conception rates in cattle. Oral supplementation with pyrroloquinoline Quinone (PQQ), an antioxidant, and inositol isomers (myo- and D-chiro-inositol) has been proven to be beneficial for fertility of women undergoing assisted reproductive biotechnologies. However, oral supplementation of these compounds to ruminant species has not been evaluated. It is unknown if PQQ and inositol isomers are soluble in the rumen environment, if they are degraded by the microbial populations which exist in this environment, or the timeframe for the ruminal degradation of these molecules resulting from oral supplementation. The objectives of this study were to 1) evaluate disappearance (solubility) of different of inositol isomers and PQQ; and 2) to quantify the in-vitro ruminal degradability of inositol isomers and PQQ over time. Inositol isomers and PQQ (0.25 g) were placed in Ankom bags and heat sealed. The bags were placed in glass beakers with an artificial saliva solution and rumen fluid, then incubated at 39 C in a warm shaker bath to simulate ruminal digestion for 0, 1, 2, 4, 8, 12, 24, and 48 h. These were then evaluated for disappearance of each form of inositol from the Ankom bag and repeated for a total of five replicates. For the second trial, only myo-inositol was evaluated. In addition to bag removal at the same time points, duplicate ruminal fluid samples were collected for myo-inositol concentration determination. This trial had seven replicates. For all forms of inositol 0.00% was removed at 0 h, and by 1 h 99.0 % inositol had disappeared (P &amp;gt; 0.05). There were two exceptions, PQQ, at 1 h was less (P &amp;lt; 0.0001; 96.33 %) and at 4 h (98.46 %). For the second trial, myo-inositol disappearance increased (P = 0.0001) from 0.00 % at 1 h to 99.53 % at 4 h and remained constant (P &amp;gt; 0.05) for subsequent sampling times. Ruminal fluid concentration of myo-inositol increased (P &amp;lt; 0.0001) from 0.197 to 5.39 g/L, and remained constant (P &amp;gt; 0.05) until h 24 when it had decreased (P &amp;lt; 0.0001) to 2.766 g/L, and decreased P &amp;lt; 0.0001) further by 48 h to 0.377 g/L. Ruminal concentration of myo-inositol was not different (P &amp;gt; 0.05) between 0 h and 48 h. These data indicates that inositol isomers and PQQ are soluble in the rumen environment, though not immediately, with myo-inositol concentrations peaking between 12 and 24 h and disappearing mostly by h 48.

Endoscopic Laser Ablation of Endometrial Cysts in Straight Egyptian Arabian Mares: Outcome on Embryo Recovery and Conception Rate

Endoscopic Laser Ablation of Endometrial Cysts in Straight Egyptian Arabian Mares: Outcome on Embryo Recovery and Conception Rate

The impact of metabolic surgery on natural conception rates in women with infertility, obesity and polycystic ovary syndrome: a retrospective study.

Women with obesity and polycystic ovary syndrome (OPOS) are at high risk for infertility. However, the reproductive effects of metabolic surgery on women with infertility and OPOS have not been fully elucidated. We investigated the natural conception rates after metabolic surgery, and the variables associated with infertility in women with OPOS. Shanghai Sixth People's Hospital, Shanghai, China. This study included 72 women with infertility and OPOS who underwent metabolic surgery and were followed up for 4 years after surgery. Finally, 54 patients completed the study. Reproductive outcomes were assessed, along with changes in anthropometric parameters and metabolic indices before and 1year after surgery (prepregnancy). Logistic regression analysis was used to identify variables influencing natural conception and delivery outcomes. After metabolic surgery, 35 patients (64.8%) became pregnant naturally, while 16 were still unable to conceive naturally. Preoperative body mass index (BMI) tended to be lower in the natural conception group than in the no natural conception group (38.9 ± 6.9 versus 43.6 ± 11.0 kg/m2, P = .070) and there were no significant differences in weight loss between the 2 groups after surgery. Logistic regression analysis showed that the BMI 1year after surgery (prepregnancy) was an independent predictor of natural conception, and receiver operating characteristic analysis showed that a BMI of 27.0 kg/m2 was the optimal cutoff for predicting successful natural conception after surgery. Metabolic surgery can improve fertility in women with OPOS. Patients with a BMI < 27.0 kg/m2 1year after surgery (prepregnancy) are more likely to become pregnant naturally and give birth.