Profile of uterine flush lipid mediators in cows with subclinical endometritis: pilot study.

Subclinical endometritis affects reproductive outcomes and causes economic losses in dairy cows, thus, it is important to understand disease progression mechanisms and develop diagnostic procedures for better disease management. We measured the levels of 146 lipid mediators in uterine flush samples using lipid chromatography-mass spectrometry. We detected 25 lipid mediators in the uterine flush of both the control and subclinical endometritis cows; 15 of the 25 lipid mediators were AA-derived metabolites. Among the AA-derived metabolites, cyclooxygenase (COX)-generated mediators were the most abundant. Specifically, levels of 11ß-13,14-dihydro-15-keto prostaglandin (PG) F2α, PGE2, PGA2, 13-hydroxyoctadecadienoic acid, and PGD1 were elevated in all the cows with subclinical endometritis. This study may provide new insights for the management of subclinical bovine endometritis.

Valproic acid elevates HIF-1α-mediated CGB expression and suppresses glucose uptake in BeWo cells.

Placental dysfunction can disrupt pregnancy. However, few studies have assessed the effects of chemical-induced toxicity on placental function. Here, we examined the effects of valproic acid (VPA) as a model chemical on production of hormones and on glucose uptake in human choriocarcinoma cell line BeWo. Cells were treated with forskolin to differentiate into syncytiotrophoblasts, which were then treated with VPA for 72 hr. Real-time RT-PCR analysis showed that VPA significantly increased the mRNA expression of chorionic gonadotropin ß (CGB), a hormone that is produced by the placenta in the first trimester of pregnancy, relative to that in the forskolin-only group. It also suppressed the increase in intracellular glucose uptake and GLUT1 level observed in the forskolin-only group. RNA-seq analysis and pathway database analysis revealed that VPA consistently decreased the level of HIF-1α protein and expression of its downstream target genes HK2 and ADM in the hypoxia pathway. Cobalt chloride, a HIF-1α inducer, inhibited CGB upregulation in VPA-treated cells and rescued VPA-induced suppression of glucose uptake and GLUT1 level. Thus, HIF-1α-mediated elevation of CGB expression and suppression of glucose uptake by VPA is a novel mechanism of placental dysfunction.

5-Aminolevulinic acid/sodium ferrous citrate improves the quality of heat-stressed bovine oocytes by reducing oxidative stress.

A high temperature-humidity index during summer has deleterious effects on mitochondrial function, reducing oocyte developmental competence. 5-Aminolevulinic acid (5-ALA) and sodium ferrous citrate (SFC) are both known to support mitochondrial function and have strong anti-oxidant and anti-apoptotic activities. This study aimed to determine the mechanism of action of 5-ALA/SFC on oocyte quality. Bovine oocytes were collected from medium-sized follicles during summer (July-September, temperature-humidity index:76.6), cultured with 0, 1, 2, 4, and 8 µM 5-ALA with SFC at a molar ratio of 1:0.125, fertilized, and cultured for 10 days. The addition of 8/1 µM 5-ALA/SFC had a deleterious effect on oocyte cleavage rate in comparison with control oocytes, but did not affect the blastocyst rate, while 1/0.125 µM 5-ALA/SFC had a significantly higher increase in blastocyst rate than 8/1 µM 5-ALA/SFC. The addition of 1/0.125 and 2/0.25 µM 5-ALA/SFC improved oocyte quality by increasing the mitochondrial distribution pattern and metaphase-II oocytes, reducing reactive oxygen species and upregulating nuclear factor erythroid-2-related factor 2, heme oxygenase-1, and superoxide dismutase-1 in oocytes, and nuclear factor erythroid-2-related factor 2 and mitochondrial transcription factor A in cumulus cells. These results indicate that 1/0.125 and 2/0.25 µM 5-ALA/SFC may support oocyte quality and developmental competence and provide anti-oxidant actions in cumulus-oocyte complexes.

Use of platelet lysate for in-vitro embryo production and treatment of repeat breeding in cows.

Platelet-rich plasma (PRP) is a biological hemocomponent derived from blood after the complete removal of red blood cells and the partial or complete removal of white blood cells to concentrate platelets in an appropriate volume of plasma. Platelets have important growth factors, cytokines, and active metabolites that improve the endometrial environment and positively affect implantation. This study evaluated the effect of the addition of activated PRP (platelets lysate; PL) on in vitro bovine oocyte maturation and embryonic development and the effect of intrauterine (IU) infusion of autologous PL in repeat breeder (RB) cows. Experiment 1 examined the effects of allogeneic PL, fetal calf serum (FCS), mixed PL + FCS, or platelet-poor plasma (PPP) supplementations to in vitro maturation and development media on in vitro oocyte maturation and embryo development in good- and poor-quality oocytes of Japanese Black cows. Experiment 2 examined the IU infusion of autologous PL, 24 h post-insemination, in 21 RB Holstein-Friesian dairy cows. The cleavage rate of good-quality oocytes was higher in the PL group (85.93 ± 2.50%) than in the PPP group (67.16 ± 3.41%) (P < 0.05), while the cleavage rate of the poor-quality oocytes was higher in the PL alone (76.13 ± 4.04%) and mixed PL + FCS treated (73.59 ± 4.22%) groups than in the PPP group (54.64 ± 2.93%) (P < 0.05). The blastocyst rate of the good-quality oocytes was higher in the PL group (40.97 ± 3.03%) than in the FCS (27.97 ± 3.31%) and PPP (25.33 ± 2.15%) groups (P < 0.05). The blastocyst rate of poor-quality oocytes and the hatching rates of both good and poor-quality oocytes showed no significant differences among all groups. The conception rate in the autologous PL-treated group was 41.67% (5/12), while it was 11.11% (1/9) in the control group. The platelets' count in the pregnant PL-treated cows (n = 5; mean ± SEM, 1.07 ± 0.10 × 109/mL) was higher than in the non-pregnant ones (n = 7; 0.67 ± 0.10 × 109/mL) (P < 0.05). In conclusion, allogeneic PL was effective in stimulating the in vitro oocyte maturation and embryonic development in both good and poor-quality bovine oocytes, and post-insemination IU infusion of autologous PL derived from high platelets' count-PRP would be recommended for the treatment of RB cows.

Inflammatory Changes and Composition of Collagen during Cervical Ripening in Cows.

Dystocia and stillbirths in cows pose a high risk of loss of both dams and fetuses, thereby resulting in high economic losses. One of the causes of these problems is birth canal abnormalities. Thus, to prevent these occurrences, it is necessary to understand the mechanisms underlying cervical ripening. Although physiological inflammatory responses and changes in collagen composition have been reported in humans and mice, related information is scarce for cows. We observed inflammatory changes and changes in the collagen composition in the cervix from late pregnancy to parturition to clarify some of the physiological changes associated with cervical ripening during normal calving in cows. Cervical mucus and tissue samples were collected from 41 Japanese Black cows at 200, 230, and 260 days of gestation and at 7-day intervals thereafter until parturition. The percentage of polymorphonuclear neutrophils (PMN%) in the mucus was calculated, and interleukin (IL)-8 concentration was determined by enzyme-linked immunosorbent assay. Blood samples were collected from the jugular vein, and leukocyte counts were determined. Picrosirius red-stained cervical tissue specimens were observed under a polarizing microscope, and the percentage of type I and type III collagen areas in the cervical tissue were calculated. The PMN% in cervical mucus was lowest at 200 days gestation (12−13 weeks before delivery), significantly increased 5 weeks before (21.7 ± 0.04), and was highest 1 week before calving (50.9 ± 0.04). IL-8 levels were increased at 295 days compared with those at 200 days of pregnancy (p < 0.05). No significant changes were observed in the white blood cell counts. The percentage of type I collagen in the cervical tissue reached a maximum (91.4 ± 0.02%) on day 200, significantly decreased after 274 days (3 weeks before calving), and continued to decrease thereafter until the week of parturition. There was no significant change in type III collagen levels. The results suggest that cervical ripening progresses when PMNs begin to infiltrate the cervix at around 260 days of gestation (5−4 weeks before parturition), IL-8, which increases at the end of pregnancy, mobilizes PMNs, and enhances inflammation, and that type I collagen changes are useful as an indicator of cervical ripening.

Usefulness of computed tomography for cryptorchidism in bulls.

Cryptorchidism is defined as the failure of the testis to descend into the scrotal position. Bulls with cryptorchidism have problems in both meat quality and husbandry management; thus, it is greatly important to accurately identify the retained testis and remove it during the early stage. Abdominal computed tomography (CT) was performed under general anesthesia in 34 bulls aged 3-9 months with cryptorchidism. All bulls underwent laparoscopic or incision approach for cryptorchidectomy, and 40 testes were dissected. The detection rates of retained testes were 64.5% in the abdominal cavity and 100% in the subcutaneous inguinal region, and the total detection rate was 72.5%. Furthermore, all cases in this study were suspected to have intra-abdominal cryptorchidism in primary care, but CT revealed that 22.5% of cases had cryptorchidism in the subcutaneous inguinal region. The CT value (mean ± standard deviation) of the retained testes was 20.96 ± 7.54 Hounsfield Unit, and the CT value and size of the retained testes showed a positive weak correlation with bovine age. Therefore, there is the demerit that general anesthesia and a huge device are necessary; nevertheless, CT is suggested to be useful in identifying the location of retained testes and selecting an appropriate surgical approach in bulls with cryptorchidism. Moreover, CT findings suggested that the maturation of the retained testes might depend not on the descending process but on age.

Association of Herd Size with Stillbirth and Dystocia Rates in Japanese Black Cattle.

The objective of this study was to investigate the effect of herd size on stillbirth and dystocia rates; the relationships between herd size, calving season, parity, and gestation length in Japanese Black cattle were also explored. Data were collected for 41,184 calvings from 15,512 animals on 905 farms between 2006 and 2010. In this study, herds were classified into three groups based on size: small (1−10 cows), medium (11−50 cows), and large (≥51 cows). Herd size had an effect on the dystocia rate (p < 0.05) but not the stillbirth rate. Additionally, interactions between herd size and gestation length were associated with the dystocia rate (p < 0.05), and the dystocia rate was the highest in small herds, followed by medium and large herds for cows with a gestation length of 281−300 days, which is considered a pregnancy of normal duration. In summary, in Japanese Black cattle, there were different effects of herd size on the stillbirth rate and dystocia rates, as herd size was associated with the dystocia rate but not with the stillbirth rate.

Impact of dystocia and cow/calf characteristics on mortality from 0 to 120 days of age in Japanese Black calves in commercial cow-calf operations.

Calf mortality severely affects productivity in the beef industry. The present study was conducted to assess the calf mortality risk (CMR) in Japanese Black calves and investigate potential associations between calf/cow information and the CMR. Records for calves born between April 2006 and March 2010 were extracted from an existing database, which included production data on commercial cow-calf operations in Miyazaki, Japan. The study group comprised 40,462 calves born to 15,600 cows on 908 farms. Because calves on the studied farms were weaned at approximately 4 months of age, the calf records were collected from birth to 120 days. The CMR was calculated as the number of dead calves divided by the number of surviving calves. Mixed-effect multivariable logistic regression modeling was used to determine potential associations between the CMR and the factors hypothesized to influence that risk. CMR analyses were performed separately for the following production stages: days 0-30, days 31-60, days 61-90 and days 91-120 after birth. Of the 40,462 calves, 1465 died during days 0-120 after birth, and the CMR was 3.6 %. Of the 1465 dead calves, 35.9 % died within 10 days after birth. During the 0-30-day period, the CMR was associated with dam parity, calving status, gestation length, sex, birth season and twin births (P < 0.05), but not with the number of inseminations to conception. Low parity, dystocia, gestation lengths < 280 days and > 301 days, male calves, calves born in autumn and winter and twin births yielded higher CMRs. Low dam parity also yielded higher CMRs during the 31-60-day, 61-90-day and 91-120-day periods (P < 0.05), but no other factors were associated with the CMR during these periods. Thus, various cow and calf factors were shown to be associated with CMRs in Japanese Black calves, and calves with these factors should be considered high-risk calves.

Longitudinal effect of repeat breeding in Japanese Black beef cattle at a low parity on subsequent fertility in commercial cow-calf operations.

Repeat breeding (RB) has been defined as failure to conceive from three or more regularly spaced services in the absence of detectable abnormalities, and cause economic loss on the farm owing to a declining conception rate. This study aimed to evaluate the reproductive characteristics of RB in Japanese Black cattle by assessing the longitudinal effect of RB at a low parity on subsequent fertility raised in commercial cow-calf operations. Data used in this study were collected from 764 farms in Miyazaki. Data from 2005 until 2014 comprised 158,945 AI records with 80,453 parity records for 22,565 cows. The effect of RB at heifers and parities 1 and 2 cows on subsequent fertility and survival on four consecutive parities was investigated. The results showed that cows with the number of inseminations to conception (INS) of ≥4 at a low parity had a higher probability of being RB again at subsequent parities compared with cattle with INS 1 or 2. Additionally, the degree of the negative effect of an INS ≥4 on fertility and survival increased as they became older. On the other hand, cows with an INS of 2 had similar fertility and survival with those with an INS of 1. In summary, this study suggests that repeat breeders at a low parity have a higher probability of RB again at subsequent parities compared with cattle with INS 1 or 2, and the negative effect of an INS ≥4 increases as parity increases.

5-Aminolevulinic acid combined with sodium ferrous citrate mitigates effects of heat stress on bovine oocyte developmental competence.

High summer temperatures have deleterious effects on oocyte developmental competence. The antioxidant and autophagy-related properties of 5-aminolevulinic acid (5-ALA) gives the compound a broad range of biological activities. This study aimed to evaluate the effects of: 1) a high temperature-humidity index (THI) on the developmental competence of bovine oocytes, and 2) 5-ALA administration in combination with sodium ferrous citrate (SFC) during in vitro maturation (IVM) on bovine oocyte developmental competence evaluated at high THI. Bovine ovaries were collected from a local slaughterhouse at moderate environmental temperature (MT; THI of 56.2) and high environmental temperature (HT; THI of 76.7) periods; cumulus-oocyte complexes (COCs) were aspirated from medium-sized follicles, matured in vitro for 22 h, fertilized, and cultured for 10 days. For COCs collected during the HT period, 0 (control), 0.01, 0.1, 0.5, or 1 µM 5-ALA was added to the maturation medium in combination with SFC at a molar ratio of 1:0.125. The results showed that HT adversely affected blastocyst and hatching rates compared with MT. Adding 5-ALA/SFC (1 µM/0.125 µM) to the maturation medium of oocytes collected during the HT period improved cumulus cell expansion and blastocyst rates compared with the no-addition control. In conclusion, this study showed that high THI can disrupt bovine oocyte developmental competence. Adding 5-ALA to SFC ameliorates this negative effect of heat stress and improves subsequent embryo development.

Intra-abdominal mass containing controlled internal drug release (CIDR) devices detected by CT in a Japanese Black cow.

This report describes an intra-abdominal mass caused by progesterone-containing controlled internal drug release (CIDR) devices in the abdominal cavity of a 28-month-old Japanese Black heifer presenting with infertility. Rectal examination revealed a mass containing a cartilage-like object in the pelvic cavity. Computed tomography revealed a mass containing two T-shaped foreign bodies. Laparotomy was performed to remove the mass containing the foreign bodies. The heifer was healthy at discharge seven days post-surgery. This case adds CIDR device as a new etiology for intra-abdominal masses. Furthermore, it highlights the usefulness of CT in diagnosing deep abdominal lesions.

Association of intrauterine presence of Lactobacillus spp. with inflammation and pathogenic bacteria in the uterus in postpartum dairy cows.

The aim of this study was to clarify the influence of Lactobacillus spp. on the degree of endometrial inflammation in the postpartum period and the relationship between Lactobacillus spp. and pathogenic bacteria in the endometrium of postpartum dairy cows. Endometrial samples were collected from 41 Holstein-Friesian cows at 4 and 8 weeks postpartum using cytobrushes for polymorphonuclear neutrophil (PMN) count and bacterial culture to isolate Lactobacillus spp., Escherichia coli, and Trueperella pyogenes. The 4-week samples were divided into four groups (E+L+), (E+L-), (E-L+), (E-L-) according to whether endometritis was diagnosed (E+) and Lactobacillus spp. was isolated (L+). The diagnostic criterion for cytological endometritis was > 18% PMN. The average PMN% in the E+L+ group was lower than that in the E+L-group (P < 0.05) at 8 weeks postpartum. There were no significant correlations between the number of colonies of Lactobacillus spp. and E. coli or between that of Lactobacillus spp. and T. pyogenes. Lactobacillus spp. could reduce PMN% in dairy cows with endometritis during the puerperal period. In conclusion, the intrauterine presence of Lactobacillus spp. may have a positive effect on uterine involution in postpartum dairy cows.

Immunohistochemical and Morphological Features of Bovine Granulosa Cell Tumours in Relation to Growth Pattern and Folliculogenesis.

Granulosa cell tumours (GCTs) are the most common type of bovine ovarian neoplasm. We describe the morphological and immunohistochemical features of GCTs (n = 26) and a thecoma (n = 1) using antibodies to cytokeratin AE1/AE3, vimentin, desmin, nectin-4, anti-Müllerian hormone (AMH), inhibin α, c-erbB-2 oncoprotein and proliferating cell nuclear antigen. The results indicate that, based on the expression similarity of AE1/AE3 and inhibin α, the macrofollicular growth pattern of GCTs derives from highly differentiated granulosa cells (GCs), the Graafian follicle or early atretic follicle. The trabecular growth pattern of GCTs is inferred to be derived from GCs of the atretic follicle in mature animals. AMH is a useful marker for diagnosing bovine sex cord-stromal tumours because it was expressed in all GCT cases and in the single case of thecoma.

Impact of summer heat stress on the thermal environment of bovine female genital tract.

Summer heat stress (HS) is associated with a reduction in conception rate, increase in services per conception, and early embryonic death. However, the impact of summer HS on the thermal environment of different regions of the bovine female genital tract remains unknown. This study aimed to elucidate the effect of summer HS on the thermal environment of different regions of the genital tract in the cow. Three non-pregnant Japanese Black cows were investigated using a specially designed digital thermometer to record the temperatures of the rectum (RT), vagina (VT), cervix (CT), uterine body (UBT), and uterine horns (UHT) on days 0, 1, 2, 3, and 8 of the estrous cycle (day 0 = heat) in February (winter), May (spring), and August (summer). During the experiment, the temperature humidity index (THI) was recorded. THI during summer was higher (P Ë‚ 0.001) than in winter and spring (78.45 ± 0.32 vs. 60.26 ± 1.20 and 68.51 ± 0.80, respectively) and was higher than the alert THI indicating HS (i.e., THI > 73). Consequently, the VT, CT, UBT, and UHT were elevated during summer HS (P < 0.05) in comparison to winter and spring. THI was positively correlated (P < 0.01) with RT, VT, CT, UBT, and UHT. Linear regression revealed that VT, CT, UBT, and UHT increased by 0.05 °C per unit of THI. VT was more highly correlated than RT with THI and with the temperature of other regions of genital tract. HS induced increases in the temperatures of different regions of the female genital tract. The relationship between THI and VT could be incorporated into a mathematical model to predict the thermal load of HS on different regions of the female genital tract.

Intrauterine infusion of povidone-iodine: Its effect on the endometrium and subsequent fertility in postpartum dairy cows.

This study aimed to describe the duration of inflammation after intrauterine infusion of polyvinylpyrrolidone-iodine (povidone-iodine, PVP-I), determine the effect of PVP-I infusion on the subsequent fertility, and evaluate the histopathology of the endometrium in dairy cows. In Experiment 1, 120 lactating clinically healthy Holstein-Friesian cows at 5 weeks postpartum (W5) were equally divided into three groups: intrauterine infusion of 2% PVP-I (PVP), saline (SAL), and no treatment (NTX). Endometrial cytology was performed daily from D0 (W5) to D7 to determine the percentage of polymorphonuclear cells (PMN%) in 44 of the 120 cows. All cows received timed artificial insemination at D17. In Experiment 2, 25 cows were randomly classified into sacrifice at 24 hr or 48 hr after 2% PVP-I infusion (PVP24 and PVP48), and 24, 48, 72, or 96 hr after SAL infusion (SAL24; SAL48; SAL72; SAL96), or no treatment (NTX). Histopathology was performed on the uterus of each cow. In Experiment 1, PMN% was greater in PVP (P<0.05) than in SAL and NTX, on D1, but decreased to a level similar to that of the other groups by D2. Conception rate was higher (P<0.05) in PVP cows compared to SAL and NTX cows. In Experiment 2, stratified columnar epithelium in the uterus disappeared in PVP24 and SAL24. The epithelium was regenerated in PVP48, SAL72, and SAL96, but not in SAL48. In conclusion, the results of the study suggest that PVP-I induces transient uterine inflammation, promotes regeneration of endometrial epithelial cells and improves fertility.

Severe Degenerative Changes in Cryptorchid Testes in Japanese Black Cattle.

This is a histopathologic and endocrinologic study of 6 calves diagnosed with cryptorchidism. Cases 1-3 were diagnosed as resembling testicular regression syndrome. In cases 1 and 2, the extracted tissue was a small, firm, gray-white mass, and there was lack of obvious testicular tissue in case 3. Histopathologically, the excised tissue in cases 1-3 was a fibrotic testicular remnant with inflammation, mineralization, hemosiderin-laden macrophages or lipofuscin-laden macrophages, and lack of germ cells and interstitial endocrine cells. These findings were compared with cases 4-6, which were diagnosed as testicular hypoplasia due to cryptorchidism. These cases had small but otherwise grossly unremarkable intra-abdominal testicular tissue and histologically had a few germ cells and sustentacular cells with arrested spermatogenesis and an increase in interstitial endocrine cells. Cases 1-3 had more severe degenerative changes compared with cases 4-6. In case 2, the average diameter of the seminiferous tubules was much smaller than in cases 4-6, and there were few tubule cross sections. Anti-Müllerian hormone (214 pg/ml) was detected in the plasma of case 2. Based on the macroscopic and histopathologic findings as well as endocrinologic profiles, the testicular degeneration in cases 1-3 was considered similar to that of testicular regression syndrome. In this condition, it is thought that a normally developing intra-abdominal testis undergoes degeneration due to heat or a vascular disorder such as torsion.

Bovine milk transcriptome analysis reveals microRNAs and RNU2 involved in mastitis.

Mastitis is a common inflammatory infectious disease in dairy cows. To understand the microRNA (miRNA) expression profile changes during bovine mastitis, we undertook a genome-wide miRNA study of normal milk and milk that tested positive on the California mastitis test for bovine mastitis (CMT+). Twenty-five miRNAs were differentially expressed (23 miRNAs upregulated and two downregulated) during bovine mastitis relative to their expression in normal milk. Upregulated mature miR-1246 probably derived from a U2 small nuclear RNA rather than an miR-1246 precursor. The significantly upregulated miRNA precursors and RNU2 were significantly enriched on bovine chromosome 19, which is homologous to human chromosome 17. A gene ontology analysis of the putative mRNA targets of the significantly upregulated miRNAs showed that these miRNAs were involved in binding target mRNA transcripts and regulating target gene expression, and a Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the upregulated miRNAs were predominantly related to cancer and immune system pathways. Three novel miRNAs were associated with bovine mastitis and were relatively highly expressed in milk. We confirmed that one of the novel mastitis-related miRNAs was significantly upregulated using a digital PCR system. The differentially expressed miRNAs were involved in human cancers, infections, and immune-related diseases. The genome-wide analysis of miRNA profiles in this study provides insight into bovine mastitis and inflammatory diseases. DATABASES: The miRNAseq generated for this study can be found in the Sequence Read Archive (SRA) under BioProject Number PRJNA421075 and SRA Study Number SRP126134 (https://www.ncbi.nlm.nih.gov/bioproject/PRJNA421075).

Release of urinary aquaporin-2-bearing extracellular vesicles is decreased in pregnant Japanese Black cattle.

Aquaporin-2 (AQP2), a vasopressin-regulated water channel, plays an important role in renal water homeostasis. It has been reported that the level of AQP2 in human urine is altered during pregnancy. However, little is known about the level of urinary AQP2 in pregnant cattle. In this study, we examined the level of AQP2-bearing extracellular vesicles (uEV-AQP2), which account for most urinary AQP2, in both heifers and cows during the gestational and postpartum periods. The level of uEV-AQP2 was significantly decreased during gestation in comparison with the other cattle examined. Similarly, the levels of EV marker proteins in uEVs, including tumor susceptibility gene 101 (TSG101) protein and apoptosis-linked gene 2-interacting protein X (ALIX), were significantly decreased during gestation. There were significant correlations between the levels of uEV-AQP2 and uEV-TSG101, or uEV-ALIX. Immunohistochemistry data from pregnant and non-pregnant cattle supported the notion that the level of uEV-AQP2 was decreased during gestation. These data indicate that the level of uEV-AQP2 is decreased in pregnant cattle, possibly through a decrease in both the number of EVs released into the urine and renal AQP2 expression.

Endocrinological characterization of an ovarian sex cord-stromal tumor with a Sertoli cell pattern in a Japanese Black cow.

A Japanese Black cow was evaluated for prolonged post-partum anestrus and enlargement of the right ovary. Transrectal ultrasonography revealed that the right ovary was markedly enlarged and had a solid appearance, while the left ovary was small and inactive. The presumptive diagnosis was directed towards granulosa-theca cell tumour (GTCT) which was supported by markedly elevated plasma anti-Müllerian hormone (AMH; 332.0 ng/ml), oestradiol (E2 ; 103.3 pg/ml) and immunoreactive inhibin (ir-INH; 2.1 ng/ml) in comparison with the diagnostic cut-off points for bovine GTCTs. Since the cow had been infertile and had swelling of the udder, slaughter was chosen. Histopathological examination revealed that the tumour was an ovarian sex cord-stromal tumour (SCST) with a Sertoli cell pattern. These findings suggest that plasma AMH, ir-INH and E2 could be possible biomarkers for bovine ovarian SCST with a Sertoli cell pattern, whereas this case could not be distinguished from GTCTs based on endocrinological profile.

Daily calving frequency and preterm calving is not associated with lunar cycle but preterm calving is associated with weather conditions in Japanese Black cows.

Several external factors including lunar cycle and weather conditions might be associated with calving conditions. Our objective here was to determine the effects of lunar cycle and weather conditions on calving frequency and the occurrence of preterm calving in Japanese Black cows. Calving records were obtained from 905 farms in Miyazaki Prefecture, Japan. Data were collected from 41,116 calvings. We conducted two studies: Study 1 investigated the effects of lunar cycle and weather conditions on daily calving frequency (DCF) with the observational unit of each day and Study 2 investigated those effects on the occurrence of preterm calving with the observational unit for each calving. Preterm calving was defined by whether or not a cow calving before 280 days of gestation, lower 10th percentile of gestation length of the collected data, and by whether or not a cow calving before 289 days of gestation, median of the gestation length. For Study 1, lunar cycle was not associated with DCF in all cows, in only primiparous cows and in only multiparous cows. As well as lunar cycle, weather conditions such as temperature, diurnal temperature variation, the temperature-humidity index, precipitation amount, barometric pressure, relative humidity and solar radiation, were also not associated with DCF. For Study 2, lunar cycle phases were not associated with the occurrence of preterm calving. However, preterm calving was associated with all of the weather conditions (P < 0.05) except for precipitation amounts and solar radiation. Temperature, the temperature-humidity index and relative humidity were positively associated with the occurrence of preterm calving. In contrast, diurnal temperature variations and barometric pressure were negatively associated with the occurrence of preterm calving. In conclusion, the lunar cycle was not associated with DCF and preterm calving, but the weather conditions were associated with preterm calving.