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Simple Summary: Early pregnancy diagnosis is of major importance to the economics of dairy herds. The detection of placental proteins, termed pregnancy-associated glycoproteins (PAGs), represents a diagnostic tool to identify both pregnant and non-pregnant cows. However, as milk production correlates negatively with plasma levels of PAGs during early pregnancy, detection of PAGs may be hindered by high milk production. This study evaluates a newly developed commercial PAGs-based pregnancy test using whole blood or plasma samples during early pregnancy (28–55 days of gestation) in high-producing dairy cows. This study evaluated a commercial pregnancy-associated glycoproteins (PAGs)-based pregnancy test using whole blood or plasma samples during early pregnancy (28–55 days of gestation) in high-producing dairy cows. Transrectal ultrasonography was used as the gold standard method. The study population constituted of 284 cows. False positive diagnoses were recorded from Day 60 to 89 and from Day 60 to 99 postpartum in blood and plasma samples, respectively. In early pregnancy screening, correct positive diagnoses were recorded in 75% and 100% of blood and plasma samples, respectively. High milk production was associated with negative results in blood samples and with the lowest test line intensity in plasma samples. False positive or negative diagnoses were recorded in 0% of both types of samples in cows previously diagnosed as pregnant and showing signs of estrus. In conclusion, the use of plasma was more effective than the use of blood in early pregnancy diagnosis. In cows previously diagnosed as pregnant and showing signs of estrus, both types of samples showed the same results. Because of large individual variations, normal single pregnancies could not be differentiated from twin pregnancies, from pregnancies with a recently dead conceptus, or from pregnancies that experienced subsequent pregnancy loss. [ABSTRACT FROM AUTHOR]

Heifer conception rate to the first service (HCR1) is defined as the number of heifers that become pregnant to the first breeding service compared to the heifers bred. This study aimed to identify loci associated and gene sets enriched for HCR1 for heifers that were bred by artificial insemination (AI, n = 2829) or were embryo transfer (ET, n = 2086) recipients, by completing a genome-wide association analysis and gene set enrichment analysis using SNP data (GSEA-SNP). Three unique loci, containing four positional candidate genes, were associated (p < 1 × 10−5) with HCR1 for ET recipients, while the GSEA-SNP identified four gene sets (NES ≥ 3) and sixty-two leading edge genes (LEGs) enriched for HCR1. While no loci were associated with HCR1 bred by AI, one gene set and twelve LEGs were enriched (NES ≥ 3) for HCR1 with the GSEA-SNP. This included one gene (PKD2) shared between HCR1 AI and ET services. Identifying loci associated or enriched for HCR1 provides an opportunity to use them as genomic selection tools to facilitate the selection of cattle with higher reproductive efficiency, and to better understand embryonic loss. [ABSTRACT FROM AUTHOR]

IntroductionReproductive efficiency in dairy cattle bred by artificial insemination (AI) or via embryo transfer (ET) is important as a means of facilitating the rate of genetic improvement by utilizing superior genetics from sires and donor dams. Fertility is especially challenging in primiparous cows as they have recently calved, are still growing, and are lactating. Fertility, measured by the conception rate from the first service (CCR1), is the number of cows that become pregnant as a result of the first AI or ET compared to all cows serviced, whereas times bred (TBRD) is the number of inseminations cows bred by AI needed to achieve a successful pregnancy.MethodsThis study aimed to identify the loci associated with and gene sets enriched for the CCR1 in primiparous cows that were bred by AI (n = 882) or were ET recipients (n = 353), and to identify the loci associated with the TBRD (n= 1,851) in primiparous cows. A genome-wide association analysis and gene set enrichment analysis were performed using single-nucleotide polymorphism (SNP) data for the CCR1 and TBRD in primiparous cows. In cows bred by AI, two loci containing five positional candidate genes were associated with the CCR1 (p < 1 × 10−5) and one gene set with 18 leading-edge genes was enriched (NES ≥3) for the CCR1.Results and discussionIn cows that were ET recipients, five loci were associated with the CCR1, but no gene sets were enriched for the CCR1. For the second phenotype, five loci with nine positional candidate genes were associated with the TBRD and two gene sets with eight leading-edge genes were enriched for the TBRD. Identifying the loci associated with or gene sets enriched for the CCR1 and TBRD provides an opportunity to better understand embryonic loss in AI-bred and ET-recipient cows and to use this information to select for higher reproductive efficiency.

Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) and is primarily transmitted by Aedes species mosquitoes; however, ZIKV can also be sexually transmitted. During the initial epidemic and in places where ZIKV is now considered endemic, it is difficult to disentangle the risks and contributions of sexual versus vector-borne transmission to adverse pregnancy outcomes. To examine the potential impact of sexual transmission of ZIKV on pregnancy outcome, we challenged three rhesus macaques (Macaca mulatta) three times intravaginally with 1 x 107 PFU of a low passage, African lineage ZIKV isolate (ZIKV-DAK) in the first trimester (~30 days gestational age). Samples were collected from all animals initially on days 3 through 10 post challenge, followed by twice, and then once weekly sample collection; ultrasound examinations were performed every 3-4 days then weekly as pregnancies progressed. All three dams had ZIKV RNA detectable in plasma on day 3 post-ZIKV challenge. At approximately 45 days gestation (17-18 days post-challenge), two of the three dams were found with nonviable embryos by ultrasound. Viral RNA was detected in recovered tissues and at the maternal-fetal interface (MFI) in both cases. The remaining viable pregnancy proceeded to near term (~155 days gestational age) and ZIKV RNA was detected at the MFI but not in fetal tissues. These results suggest that sexual transmission of ZIKV may represent an underappreciated risk of pregnancy loss during early gestation.

This study evaluated a commercial pregnancy-associated glycoproteins (PAGs)-based pregnancy test using whole blood or plasma samples during early pregnancy (28–55 days of gestation) in high-producing dairy cows. Transrectal ultrasonography was used as the gold standard method. The study population constituted of 284 cows. False positive diagnoses were recorded from Day 60 to 89 and from Day 60 to 99 postpartum in blood and plasma samples, respectively. In early pregnancy screening, correct positive diagnoses were recorded in 75% and 100% of blood and plasma samples, respectively. High milk production was associated with negative results in blood samples and with the lowest test line intensity in plasma samples. False positive or negative diagnoses were recorded in 0% of both types of samples in cows previously diagnosed as pregnant and showing signs of estrus. In conclusion, the use of plasma was more effective than the use of blood in early pregnancy diagnosis. In cows previously diagnosed as pregnant and showing signs of estrus, both types of samples showed the same results. Because of large individual variations, normal single pregnancies could not be differentiated from twin pregnancies, from pregnancies with a recently dead conceptus, or from pregnancies that experienced subsequent pregnancy loss.

ABSTRACT: Recessive alleles represent genetic risk in populations that have undergone bottleneck events. We present a comprehensive framework for identification and validation of these genetic defects, including haplotype-based detection, variant selection from sequence data, and validation using knockout embryos. Holstein haplotype 2 (HH2), which causes embryonic death, was used to demonstrate the approach. Holstein haplotype 2 was identified using a deficiency-of-homozygotes approach and confirmed to negatively affect conception rate and stillbirths. Five carriers were present in a group of 183 sequenced Holstein bulls selected to maximize the coverage of unique haplotypes. Three variants concordant with haplotype calls were found in HH2: a high-priority frameshift mutation resulting, and 2 low-priority variants (1 synonymous variant, 1 premature stop codon). The frameshift in intraflagellar 80 (IFT80) was confirmed in a separate group of Holsteins from the 1000 Bull Genomes Project that shared no animals with the discovery set. IFT80-null embryos were generated by truncating the IFT80 transcript at exon 2 or 11 using a CRISPR-Cas9 system. Abattoir-derived oocytes were fertilized in vitro, and zygotes were injected at the one-cell stage either with a guide RNA and CAS9 mRNA complex (n = 100) or Cas9 mRNA (control, n = 100) before return to culture, and replicated 3 times. IFT80 is activated at the 8-cell stage, and IFT80-null embryos arrested at this stage of development, which is consistent with data from mouse hypomorphs and HH2 carrier-to-carrier matings. This frameshift in IFT80 on chromosome 1 at 107,172,615 bp (p.Leu381fs) disrupts WNT and hedgehog signaling, and is responsible for the death of homozygous embryos.

ABSTRACT: A 60% pregnancy success for inseminations is targeted to optimize production efficiency for dairy cows within a seasonal, pasture-grazed system. Routine measures of pregnancy success are widely available but are limited, in practice, to a gestation stage beyond the first 28 d. Although some historical data exist on embryonic mortality before this stage, productivity of dairy systems and genetics of the cows have advanced significantly in recent decades. Accordingly, the aim was to construct an updated estimate of pregnancy success at key developmental stages during the first 70 d after insemination. Blood samples were collected for progesterone concentrations on d 0 and 7. A temporal series of 4 groups spanning fertilization through d 70 were conducted on 4 seasonal, pasture-grazed dairy farms (n = 1,467 cows) during the first 21 d of the seasonal breeding period. Morphological examination was undertaken on embryos collected on d 7 (group E7) and 15 (group E15), and pregnancy was diagnosed via ultrasonography on approximately d 28 and 35 (group E35) as well as d 70 (group E70). Fertilization, embryo, and fetal evaluation for viability established a pregnancy success pattern. Additionally, cow and on-farm risk factor variables associated with pregnancy success were evaluated. We estimated pregnancy success rates of 70.9%, 59.1%, 63.8%, 62.3%, and 56.7% at d 7, 15, 28, 35, and 70, respectively. Fertilization failure (15.8%) and embryonic arrest before the morula stage (10.3%) were the major developmental events contributing to first-week pregnancy failures. Embryo elongation failure of 7% contributed to pregnancy failure during the second week. The risk factors for pregnancy success that were related to the cows included interval between calving and insemination, and d-7 plasma progesterone concentrations, whereas insemination sire was associated with pregnancy outcome. Most pregnancy failure occurs during the first week among seasonal-calving pasture-grazed dairy cows.

A 60% pregnancy success for inseminations is targeted to optimize production efficiency for dairy cows within a seasonal, pasture-grazed system. Routine measures of pregnancy success are widely available but are limited, in practice, to a gestation stage beyond the first 28 d. Although some historical data exist on embryonic mortality before this stage, productivity of dairy systems and genetics of the cows have advanced significantly in recent decades. Accordingly, the aim was to construct an updated estimate of pregnancy success at key developmental stages during the first 70 d after insemination. Blood samples were collected for progesterone concentrations on d 0 and 7. A temporal series of 4 groups spanning fertilization through d 70 were conducted on 4 seasonal, pasture-grazed dairy farms (n = 1,467 cows) during the first 21 d of the seasonal breeding period. Morphological examination was undertaken on embryos collected on d 7 (group E7) and 15 (group E15), and pregnancy was diagnosed via ultrasonography on approximately d 28 and 35 (group E35) as well as d 70 (group E70). Fertilization, embryo, and fetal evaluation for viability established a pregnancy success pattern. Additionally, cow and on-farm risk factor variables associated with pregnancy success were evaluated. We estimated pregnancy success rates of 70.9%, 59.1%, 63.8%, 62.3%, and 56.7% at d 7, 15, 28, 35, and 70, respectively. Fertilization failure (15.8%) and embryonic arrest before the morula stage (10.3%) were the major developmental events contributing to first-week pregnancy failures. Embryo elongation failure of 7% contributed to pregnancy failure during the second week. The risk factors for pregnancy success that were related to the cows included interval between calving and insemination, and d-7 plasma progesterone concentrations, whereas insemination sire was associated with pregnancy outcome. Most pregnancy failure occurs during the first week among seasonal-calving pasture-grazed dairy cows. [Display omitted] [ABSTRACT FROM AUTHOR]

Recessive alleles represent genetic risk in populations that have undergone bottleneck events. We present a comprehensive framework for identification and validation of these genetic defects, including haplotype-based detection, variant selection from sequence data, and validation using knockout embryos. Holstein haplotype 2 (HH2), which causes embryonic death, was used to demonstrate the approach. Holstein haplotype 2 was identified using a deficiency-of-homozygotes approach and confirmed to negatively affect conception rate and stillbirths. Five carriers were present in a group of 183 sequenced Holstein bulls selected to maximize the coverage of unique haplotypes. Three variants concordant with haplotype calls were found in HH2: a high-priority frameshift mutation resulting, and 2 low-priority variants (1 synonymous variant, 1 premature stop codon). The frameshift in intraflagellar 80 (IFT80) was confirmed in a separate group of Holsteins from the 1000 Bull Genomes Project that shared no animals with the discovery set. IFT80-null embryos were generated by truncating the IFT80 transcript at exon 2 or 11 using a CRISPR-Cas9 system. Abattoir-derived oocytes were fertilized in vitro, and zygotes were injected at the one-cell stage either with a guide RNA and CAS9 mRNA complex (n = 100) or Cas9 mRNA (control, n = 100) before return to culture, and replicated 3 times. IFT80 is activated at the 8-cell stage, and IFT80-null embryos arrested at this stage of development, which is consistent with data from mouse hypomorphs and HH2 carrier-to-carrier matings. This frameshift in IFT80 on chromosome 1 at 107,172,615 bp (p.Leu381fs) disrupts WNT and hedgehog signaling, and is responsible for the death of homozygous embryos. [ABSTRACT FROM AUTHOR]

Widespread genotyping has enabled the identification of putative recessive mutations that affect fertility through early embryonic fetal loss, or that compromise neonate or calf viability. The use of artificial insemination in the global dairy population can rapidly spread these harmful mutations, and testing for multiple mutations can become relatively expensive if not all tests are available on the same SNP panel. However, it is possible to provide heifer and cow predicted carrier status to farmers at no additional cost if the animals are genotyped with a standard SNP panel. Additionally, for defects where the causal mutation is unknown but a haplotype of markers has been associated with the defect, the carrier status can be predicted based on that haplotype. The aims of this study were 3-fold: (1) to determine the accuracy of imputation of putative causal mutations for recessive deleterious conditions in Australian dairy cattle, (2) to impute carrier status for known recessive deleterious conditions in all genotyped Australian Holstein, Jersey, and Red breed cows, and (3) to determine the changes in carrier frequencies across time for these recessive deleterious mutations. We used the F1 statistic, combining precision and recall, to assess the accuracy of carrier status prediction. We showed that known deleterious mutations can be accurately imputed in Australian Holstein and Jersey cattle that are not directly genotyped for the causal mutation, with F1 ranging between 0.88 and 0.99. For recessive deleterious conditions not included on the standard Australian SNP panel, carrier status could be predicted using a marker haplotype, with F1 ranging from 0.91 to 0.92. Most putative causals and haplotypes were either stable with a low carrier percentage or had a declining carrier percentage. However, several recessive mutations showed a relatively high or increasing percentage, highlighting the importance of detecting carriers to reduce the number of at-risk matings. Furthermore, the high carrier percentage of the recently identified bovine lymphocyte intestinal retention defect mutation emphasizes the importance of detection of novel mutations., (The Authors. Published by Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

ABSTRACT: Determining if reproductive failures in ewes at the semiarid region in the state of Bahia are related to the consumption of the species Cenostigma pyramidale (Tul.) Gagnon & G.P. Lewis, and this study was developed using pregnant ewes divided into six groups: G1, G2, G3, G4 with six animals each, G5 and G6 with ten animals. Each group received fence leaves in the proportion of 1%, 2%, 0.5%, and 0.25% of live weight (LW) respectively; G5 and G6, with ten animals each, receiving 0.25% and 0.5% of the LW, respectively, and the Control Group, comprising 16 ewes, were grass feeding (Cynodon dactylon). Ewes from G1 to G4 were the same, except for two, and started ingestion of the plant four days after ending of natural mating on the 80th day of gestation, while those regarding from G5 to G6 groups started ingestion on the 26th day of gestation ending on the 98 day. The ultrasonographic test was performed weekly. In G1 ewes (1%), there was an embryonic loss on the 32nd and 39th days of gestation and abortion on the 46th day. In G2 (2%), the embryo loss was earlier (on the 26th day of gestation), and abortion on the 46th day of gestation. In G3 group (0.5%), there was an embryonic loss around the 40th day of gestation. In G4 group (0.25%), it was observed the occurrence of one death lamb with bone malformations. In G6 (0.5%), abortion occurred later (108 days), followed by retained placenta. This was also verified in G5 group (0.25%). The presence of fetal malformation was found in death lambs born in G4 group, born alive from G5 and G6 groups, and one aborted from G6. In G5 and G6 groups, there were also genetic alterations on surviving lambs. In addition to these results, recurrent estrus was observed without gestation in G1, G2, G3, and G4 ewes. From the Control Group, 13 normal lambs were born without genetic alterations; furthermore, concerning a quadruple birth, three lambs were born dead. The results infer that species of C. pyramidale in low doses causes reproductive losses in pregnant ewes, therefore it is not recommended for sheep diet over the first 60 days of gestation.

Background: Hormonal and physiological changes during pregnancy period have significant effects on animals’ metabolisms. The purpose ofthe present study is to evaluate the variations of aspartate aminotransferase (AST) and gamma-glutamyl transferase (GGT) levels according to different gestation trimesters of the pregnant mares to assess changes of embryonic losses and abortions. Materials, Methods & Results: Blood samples from 49 throughbred mares were analysed during this study. Age ratio of the mares is 5-18 years and their body condition score (BCS; score 1 to 9) varies between 5 and 6. A total of 28 mares had given birth to healthy foals at the end of a healthy gestation period (Group C), whereas 11 mares had embryonic losses (Group E) and 10 mares had late period abortions (Group A). Following the confirmation of pregnancy, one blood sample per gestation trimester were taken (14-16 days of pregnancy for 1st trimester; 180 days for 2nd trimester, 270 days for 3rd trimester). Early embryonic losses (loss of a 16-25 days embryo) were observed in 6 of 11 mares in Group E and the 5 of 11 mares had late period embriyonic losses (loss of a 35-40 days embryo). In Group A, 6 mares had the abortion within 7th month and the remaining 4 mares had the abortion within the 8th month of pregnancy. Repeated Measures ANOVA, Kruskal-Wallis test and Mann-Whitney test were performed for statistical analysis, the mean AST level in Group C (n = 28) was higher during the 1st trimester in comparison to 2 following trimesters (respectively: P = 0.011 ; P = 0.01). Besides, no statistical difference was observed between 2nd and 3rd trimester regarding AST activation (P > 0.05). The mean GGT level in Group C was significantly decreased lower in the 3rd trimester compared to 1st and 2nd trimester (respectively: P = 0.007 ; P = 0.009). No statistical difference was observed between 2nd and 3rd trimester regarding GGT activation (P > 0.05). Among all groups (C, E, A) no significant difference was observed on AST levels (P > 0.05), nonetheless GGT levels had a significant rise (P = 0.039) in Group A in comparison to the 1st trimester levels of Group C. In Group A, there was a statistical decrease of AST during the 2nd trimester in comparison to the 1st trimester (P = 0.001), accompanied by a decrease of GGT activation during the 2nd trimester compared to the 1st trimester (P = 0.009). Discussion: The aminotransferases are catalisors that play an important role on the metabolism of amino acids and carbonhydrates. Although serum AST levels were within the reference ranges during 3 trimesters in this study, serum AST levels were determined to be decreased in the 2nd and 3rd trimesters in healthy pregnant mares compared to the 1st trimester. It is thought that these results can be obtained due to the increase in metabolic needs during pregnancy. In this study, serum GGT levels remained within physiological limits with a tendency to decrease as the pregnancy advances, in accordance with previous study results. Serum GGT levels that are used as an indicator to liver damage may vary during the pregnancy as a result of increased metabolic load. It is thought that the increase of serum GGT levels in Group A might be related to the fetal (chromosome-related) issues that may result to pregnancy losses. As a result, it is considered that serum AST and GGT levels in mares might be valuable parameters that predict embryonic loss or abortus cases. [ABSTRACT FROM AUTHOR]

Objective: to evaluate the clinical efficacy and safety of Femibion Natalcare vitamin complex containing metafolin in women of late reproductive age with MTHFR C677T genetic polymorphism who had anamnestic embryonic losses. Materials and methods. Study included 100 women of late reproductive age with MTHFR C677T genetic polymorphism and anamnestic embryonic losses. Patients of main group were divided in subgroups: first – 45 women who received folic acid (400 mcg per day) and second – 55 patients who received vitamin complex Femibion Natalcare 1 tablet daily. Prescription of medications began before preconception (6–8 weeks), intake ended at 28 weeks of gestation. Control group included 40 healthy women with physiological pregnancy. The studied parameters reflected information about the features of the pregnancy and birth. Results. After a course of prophylactic supplementation with Femibion Natalcare compared with monotherapy of folic acid, it was possible to reliably reduce cases of early pregnancy loss (p =0.03), anemia in I trimester (p =0.009), preeclampsia (p =0.014), anemia in II and III trimesters (p =0.001), placental dysfunction (p =0.0005), decrease in the level of placental hormones (p =0.014), pathology of placental development and localization (p =0.0499), fetal growth retardation (p =0, 0499), premature maturation of placenta (p =0.02), induction of labor (p =0.015), disorders of neonatal adaptation (p =0.03), neonatal jaundice (p =0.018), postpartum anemia (p =0.015). There were no cases of side effects of drugs on the mother and child. Conclusions. The use of a vitamin complex containing active folate metapholine for women of late reproductive age with MTHFR C677T genetic polymorphism and anamnestic embryonic losses had a positive effect on clinical symptoms, helps to reduce cases of perinatal pathology and impaired early neonatal adaptation.

Epidermal growth factor (EGF) concentrations in the uterus show two peaks on days 2–4 and 13–14 during the estrous cycle in fertile cows. Loss of the two peaks has been linked to reduced fertility in repeat breeder cows. This study aimed to examine the effect of seminal plasma (SP) on normalizing endometrial EGF concentrations and restoring fertility in repeat breeder cows with low EGF concentrations on day 3. In study 1, we examined the effect of the deposition sites (the vagina and uterus) of SP on the endometrial EGF concentrations in repeat breeder cows. SP infusion into the vagina, but not uterus, on the first day of the estrus cycle (day 0) normalized the endometrial EGF concentrations (≥ 4.7 ng/g tissue weight) on day 3. In study 2, the effect of SP volume (0.5 and 10 ml of SP and 0.5 ml of SP diluted to 10 ml) on EGF concentrations was examined. All groups with SP infusion had increased EGF concentrations on day 3, and cows with 10 ml of SP and 0.5 ml of SP diluted to 10 ml showed the highest levels of EGF concentrations. In study 3, we examined the effect of SP infusion on fertility. SP infusion normalized two peaks of endometrial EGF concentrations in about 60% of repeat breeder cows and produced more pregnancies than the controls (44.4 vs. 19.4%). Therefore, we concluded that SP may contain an activity to normalize the EGF profile and restore fertility in repeat breeder cows with altered EGF profiles.

Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) and is primarily transmitted by Aedes species mosquitoes; however, ZIKV can also be sexually transmitted. During the initial epidemic and in places where ZIKV is now considered endemic, it is difficult to disentangle the risks and contributions of sexual versus vector-borne transmission to adverse pregnancy outcomes. To examine the potential impact of sexual transmission of ZIKV on pregnancy outcome, we challenged three rhesus macaques (Macaca mulatta) three times intravaginally with 1 x 107 PFU of a low passage, African lineage ZIKV isolate (ZIKV-DAK) in the first trimester (~30 days gestational age). Samples were collected from all animals initially on days 3 through 10 post challenge, followed by twice, and then once weekly sample collection; ultrasound examinations were performed every 3-4 days then weekly as pregnancies progressed. All three dams had ZIKV RNA detectable in plasma on day 3 post-ZIKV challenge. At approximately 45 days gestation (17-18 days post-challenge), two of the three dams were found with nonviable embryos by ultrasound. Viral RNA was detected in recovered tissues and at the maternal-fetal interface (MFI) in both cases. The remaining viable pregnancy proceeded to near term (~155 days gestational age) and ZIKV RNA was detected at the MFI but not in fetal tissues. These results suggest that sexual transmission of ZIKV may represent an underappreciated risk of pregnancy loss during early gestation.

Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) and is primarily transmitted by Aedes species mosquitoes; however, ZIKV can also be sexually transmitted. During the initial epidemic and in places where ZIKV is now considered endemic, it is difficult to disentangle the risks and contributions of sexual versus vector-borne transmission to adverse pregnancy outcomes. To examine the potential impact of sexual transmission of ZIKV on pregnancy outcome, we challenged three rhesus macaques (Macaca mulatta) three times intravaginally with 1 x 107 PFU of a low passage, African lineage ZIKV isolate (ZIKV-DAK) in the first trimester (~30 days gestational age). Samples were collected from all animals initially on days 3 through 10 post challenge, followed by twice, and then once weekly sample collection; ultrasound examinations were performed every 3-4 days then weekly as pregnancies progressed. All three dams had ZIKV RNA detectable in plasma on day 3 post-ZIKV challenge. At approximately 45 days gestation (17-18 days post-challenge), two of the three dams were found with nonviable embryos by ultrasound. Viral RNA was detected in recovered tissues and at the maternal-fetal interface (MFI) in both cases. The remaining viable pregnancy proceeded to near term (~155 days gestational age) and ZIKV RNA was detected at the MFI but not in fetal tissues. These results suggest that sexual transmission of ZIKV may represent an underappreciated risk of pregnancy loss during early gestation. [ABSTRACT FROM AUTHOR]

The aim of the study, the relationship between coagulation parameters and embryonic loss in embryo transferred (ET) cows and heifers wereevaluated. The animal material of this study consisted of 19 cows and 19 heifers on farms located in East Mediterranean Agriculture Research Institute in Adana. Blood samples were collected before the ET application from the recipient cows and heifers. Coagulation parameters measured included prothrombin time (PT), activated thromboplastin time (APTT), fibrinogen, thrombin time (TT), anti-thrombin-III (AT3) and D-dimer using by Sysmex® CA-7000 and activated protein C resistance, protein C and protein S using by Sysmex CS-5100. The pregnancy rate was found 5/19 (26.3%) and 5/19 (26.3%) in cows and in heifers, respectively (P>0.05). The embryonic mortality ratio in cows was 60% (3/5) and in heifers it was 40% (2/5). The differences of D-dimer levels between pregnant and non-pregnant animals were significant (P<0.05). The APTT levels between the groups with pregnancy and embryonic loss were significantly different (P<0.05). As a result, it was determined that there is a relationship between plasma D-Dimer levels and embryonic loss in cows that were transferred embryo. To the best of authors' knowledge, this is the first study reporting the relationship between coagulation parameters and embryonic loss in ET cows and heifers. [ABSTRACT FROM AUTHOR]

The experimental objective was to examine the role of melatonin and its pathways in the maintenance of pregnancy in lactating dairy cows. Blood samples were collected at days 0, 16 and 32 after timed AI from cows (n = 200) in order to consider plasma melatonin concentrations and to conduct AOPP (advanced oxidation products of proteins) and TBARS (thiobarbituric acid reactive substances) tests. Luminal endometrial cells were collected at day 16 using a Cytobrush in all cows to determine mRNA expressions of melatonin receptor 1 (MT1), mouse double minute 2 (MDM2), MDM2 binding protein (MTBP), BCL2-associated X, apoptosis Regulator (BAX), p53 upregulated modulator of apoptosis (PUMA, gene symbol BBC3), mucin 1 (MUC1) and leukemia inhibitory factor (LIF). Plasma concentrations of melatonin were significantly greater in pregnant cows diagnosed pregnant at day 16 who sustained pregnancy to day 32 compared to nonpregnant cows at day 16, or pregnant at day 16 and who lost embryos by days 32. Concentrations of AOPP and TBARS were greater in nonpregnant cows at day 16 or pregnant at day 16 and who lost embryos by days 32 compared to those diagnosed pregnant at day 16 and who sustained pregnancy to day 32. In pregnant cows, endometrial mRNA expressions of MDM2, MTBP, MTR1 and LIF were higher compared to pregnant–embryo-loss cows (p < 0.05). In contrast, mRNA expressions of BBC3 and MUC1 were greater at day 16 in pregnant–embryo-loss cows compared to pregnant cows (p < 0.05). In conclusion, melatonin status is a modulator of embryo well-being and maintenance of pregnancy in lactating dairy cows.

Abstract Background Pregnancy loss is a major source of infertility in dairy cows. Despite a fertilization rate after insemination (AI) of approximately 90%, calving rates are 30%–50%, indicating the occurrence of extensive embryonic and foetal losses. The aim of this study was to establish the extent and pattern of embryonic and foetal loss in Swedish Red (SR) and Swedish Holstein (SH) dairy cows, as well as, the relationship to oestrus intensity (OI) and progesterone (P4) concentration. In total, 2130 AIs and 16,176 milk P4 samples from 359 SR and 212 SH dairy cows were included in the study. Pregnancy losses were estimated using data from P4 values combined with AI information and calving data. Results Total pregnancy loss from AI to the day of calving was 65%. Early embryonic loss, late embryonic loss and foetal loss were estimated to be 29, 14 and 13%, respectively. There is strong evidence in the literature that P4 concentrations at different time points are associated with pregnancy loss. In the present study, cows with pregnancy losses had significantly higher P4 levels at the day of AI and significantly lower P4 concentration at days 10, 21 and 30 after AI compared to pregnant cows. Swedish Red cows had significantly lower total pregnancy losses compared to SH cows (62% and 68% respectively, P = 0.017). Early embryonic loss was 6.7% points lower for cows inseminated at a stronger OI (OI = 3) compared to at a weaker OI (OI = 2, P = 0.006). Cows inseminated at ovulation number ≥ 5 had significantly lower early pregnancy losses compared to cows inseminated at first or second ovulation (11.5 and 8% points, respectively, P

Several tools exist to diagnose pregnancy in dairy cattle. However, substantial pregnancy loss occurs within the first 60 d of gestation in cattle, and these losses have a profound adverse economic impact on the dairy and beef cattle industries. Detecting these impending pregnancy losses could offer producers an opportunity to reduce costs associated with this source of reproductive inefficiency. Several of the pregnancy diagnostic tools currently available and new technologies are being examined for their ability to predict pregnancies at risk for failing in early pregnancy. This review provides a synopsis of work undertaken recently to predict pregnancy losses in cattle. Currently, opportunities to predict pregnancy loss include (1) using transrectal ultrasonography to detect loss of the fetal heartbeat, floating debris within the placental fluids, and reductions in fetal size; (2) observing reductions in circulating progesterone concentrations; (3) detecting reductions in concentrations of circulating placental products; namely, pregnancy-associated glycoproteins and microRNAs; and (4) detecting reductions in the early pregnancy-dependent increase in interferon-stimulatory gene expression in peripheral blood leukocytes. An achievable goal may be to identify markers of embryo mortality so that researchers and clinicians can focus their efforts on developing intervention strategies for cows identified to be at risk for pregnancy failure. [ABSTRACT FROM AUTHOR]

Association between circulating progesterone and oestradiol-17β concentrations and embryonic loss in Frisian cows (n=105) under Egyptian condition was investigated. Total embryonic losses in present study were 26.4%. On d25, progesterone (P4) concentrations and sonography revealed 79.3% cows were continuing gestation and 20.7% lost their pregnancies (early embryonic loss, EEL). Furthermore, 7.4% cows with late embryonic loss (LEL) were detected between d25-42. An increase in P4 levels started from day 4 to 7 in cows diagnosed pregnant compared to low P4 in cows that lost pregnancy (p<0.05). Cows with LEL had decrease in P4 from d28. Estradiol (E2) concentrations increased (p<0.05) in cows with EEL starting from d4 to 21 after AI compared to cows diagnosed pregnant. Starting from d4 to 40 after AI, P4/E2 ratio was higher (p<0.05) in cows diagnosed pregnant compared to cows exhibiting EEL loss, while cows with LEL had highest P4/E2 ratio till d25 post-AI and declined from d28 to 40. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the association between circulating (Progesterone, oestradiol-17β and P4/E2 ratio) concentrations and embryonic loss in Friesian cows under Egyptian condition. On day 25 by both progesterone (P4) level and sonography, 65.71% (69/105) cows continued their gestation normally and 17.14% (18/105) cows didn't conceive. While, 17.14% (18/105) of inseminated cows showed high progesterone level firstly and decline before day 25 suspecting early pregnancy loss, EPL. Also, 5 cows (7.25%) of the pregnant cows lost their feti from day 25 to day 45 (late pregnancy loss, LPL) were detected. Blood progesterone concentrations (P4 ) increased significantly in cows diagnosed pregnant (P<0.05) compared to low P4 in cows lost pregnancy (8.03 & 8.98 ng/ml vs. 4.4 & 4.9 ng/ml respectively), starting from day 4 to day 7after AI. Cows with LPL showed increasing P4 concentration in the first 25 days and got down on days 28 and 40 accompanied with embryonic loss. concentrations of estradiol were increased significantly(P<0.05) in cows with EPL starting from days 4 to 21 after AI compared to cows diagnosed pregnant. P4/E2 ratio was significantly (P<0.05) higher in cows diagnosed pregnant starting from days 4 to 40 after AI compared to cows loss their embryos early from days 4 to 25 after mating, while LPL cows has highest P4/E2 ratio during 25 days post AI and declined on days 28 to 40 in Friesian cows. It can concluded that the percentage of EPL was 17.14% and the percentage LPL was 7.25% during the first 45 days post mating in Friesian dairy cows raised in Sakha Experimental Station. [ABSTRACT FROM AUTHOR]

An autosomal recessive genetic defect termed JH1 has been associated with early embryonic loss in the Jersey cattle breed. The genetic basis has been identified as a cytosine to thymine mutation in the CWC15 gene that changes an amino acid from arginine to a stop code. To screen for JH1 carriers in an imported Jersey population in China, a method based on a polymerase chain reaction amplification followed by a restriction fragment length polymorphism assay (PCR-RFLP) was developed for the accurate diagnosis of the JH1 allele. A total of 449 randomly chosen cows were examined with the PCR-RFLP assay, and 31 were identified as JH1 carriers, corresponding to a carrier frequency of 6.9%. The PCR-RFLP method was validated by DNA sequencing of 8 positive and 13 negative samples, with all 21 samples giving the expected DNA sequence. In addition, 3 negative and 3 positive samples were confirmed by a commercial microarray-based single nucleotide polymorphism assay. Finally, samples from 9 bulls in the United States of known status were correctly identified as carriers (5 bulls) or noncarriers (4 bulls). As the JH1 defect has most likely spread worldwide, implementing routine screening is necessary to avoid the risk of carrier-to-carrier matings and to gradually eradicate the deleterious gene. [ABSTRACT FROM AUTHOR]

The experimental objective was to examine the role of melatonin and its pathways in the maintenance of pregnancy in lactating dairy cows. Blood samples were collected at days 0, 16 and 32 after timed AI from cows (n = 200) in order to consider plasma melatonin concentrations and to conduct AOPP (advanced oxidation products of proteins) and TBARS (thiobarbituric acid reactive substances) tests. Luminal endometrial cells were collected at day 16 using a Cytobrush in all cows to determine mRNA expressions of melatonin receptor 1 (MT1), mouse double minute 2 (MDM2), MDM2 binding protein (MTBP), BCL2-associated X, apoptosis Regulator (BAX), p53 upregulated modulator of apoptosis (PUMA, gene symbol BBC3), mucin 1 (MUC1) and leukemia inhibitory factor (LIF). Plasma concentrations of melatonin were significantly greater in pregnant cows diagnosed pregnant at day 16 who sustained pregnancy to day 32 compared to nonpregnant cows at day 16, or pregnant at day 16 and who lost embryos by days 32. Concentrations of AOPP and TBARS were greater in nonpregnant cows at day 16 or pregnant at day 16 and who lost embryos by days 32 compared to those diagnosed pregnant at day 16 and who sustained pregnancy to day 32. In pregnant cows, endometrial mRNA expressions of MDM2, MTBP, MTR1 and LIF were higher compared to pregnant–embryo-loss cows (p < 0.05). In contrast, mRNA expressions of BBC3 and MUC1 were greater at day 16 in pregnant–embryo-loss cows compared to pregnant cows (p < 0.05). In conclusion, melatonin status is a modulator of embryo well-being and maintenance of pregnancy in lactating dairy cows. [ABSTRACT FROM AUTHOR]

Objective: To determine whether embryo quality is associated with early spontaneous loss rates in twin and singleton pregnancies after IVF/intracytoplasmic sperm injection (ICSI). Design: Retrospective, single center analysis. Setting: The Center of Reproductive Medicine, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy. Patient(s): Women undergoing IVF/ICSI and two- or three-embryo transfer of intermediate- and top-quality embryos. Intervention(s): First-trimester sonography at 6 to 7 weeks to determine number of embryos with positive heartbeat. Number of embryos lost was calculated from a second-trimester sonogram. Main Outcome Measure(s): Rates of total pregnancy loss, as related to embryo quality, initial number of embryos, maternal age <35 or ≥35 years, and IVF procedure. Results: A total of 94 losses (23.1% of 407 pregnancies) were counted, with similar proportions in pregnancies after transfer of intermediate- or top-quality embryos. Neither the mode of IVF procedure nor the number of transferred embryos affected the loss rate. In contrast, the loss rate was significantly higher in older mothers after transfer of intermediate-quality embryos (odds ratio [OR 2.4], 95% confidence interval [CI] 1.1–5.5). Losses among singletons were significantly higher compared with losses among twins (OR 2.5, 95% CI 1.1–6.0), but this was observed in top-quality embryos only. Conclusion(s): Top-quality but not intermediate-quality ETs are associated with lower early spontaneous loss rates among twin pregnancies after IVF/ICSI. [Copyright &y& Elsevier]

Objective: To determine whether pregnancies after IVF, with and without intracytoplasmic sperm injection (ICSI), have different early spontaneous loss rates. Design: Retrospective analysis of IVF/ICSI dataset. Setting: The Center of Reproductive Medicine, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy. Patient(s): Women undergoing IVF with or without ICSI. Intervention(s): First-trimester sonography at 6-7 weeks to count the number of embryos with positive heartbeat. The number of embryos lost was calculated from a second-trimester sonogram. Main Outcome Measure(s): Embryonic loss rates related to the initial number of embryos, maternal age <35 or > or =35 years, and IVF procedure. Result(s): In vitro fertilization and ICSI had similar embryonic loss rates (odds ratio [OR] 1.2, 95% confidence interval [CI] 0.9-1.7, and OR 1.3, 95% CI 0.9-1.8 for women aged <35 years and > or =35 years, respectively). Younger women had fewer losses after IVF (OR 0.7, 95% CI 0.5-0.9). Multiples had lower loss rates compared with singleton pregnancies. Conclusion(s): In vitro fertilization and ICSI have similar spontaneous embryonic loss rates. Factors other than the initial number of embryos, maternal age, and IVF technique, such as embryo quality or uterine environment, might be involved in the outcome of multiple pregnancies in assisted reproductive technology procedures. [ABSTRACT FROM AUTHOR]

Previously, we documented lowered calving success in captive muskoxen raised for 6 years on a low nutritional plane. In an effort to identify causes of lowered calf production, we looked at serum progesterone during the breeding season in muskoxen raised on either a high (HP) or low (LP) nutritional plane. Complete cessation of estrous cycli-city in 2 parous cows was the only irregularity identified. Abortion and/or embryonic loss occurred in both HP and LP cows. We also compared progesterone during pregnancy between the 2 nutritional planes and lactating and non-lacta-ting cows. The timing of the rise and fall of the mid-pregnant progesterone peak was consistent with stage of gestation and apparently independent of time of breeding, diet or lactational status.