Progesterone-independent endometrial mRNA expression in dairy cows with clinical or subclinical endometritis.

Up to 50 % of dairy cows fail to resolve uterine involution and develop chronic clinical (CE) or subclinical endometritis (SE) 21 days after calving. Clinical endometritis is associated with purulent discharge, while SE is not associated with overt clinical signs. Along with numerous knowledge gaps related to its pathogenesis, SE does not allow for a straightforward and effective therapy. Therefore, it is crucial to unravel differences in the expression of genes among healthy, CE, and SE cows. This might contribute to the discovery of new drug candidates and, in consequence, a potentially effective treatment. In the present study, cows between 21 and 28 days postpartum (PP) were examined using vaginoscopy for the presence of vaginal discharge and endometrial cytology for the determination of the endometrial polymorphonuclear cell (PMN) percentage. Next, an endometrial biopsy sample was taken to investigate the expression of 13 selected candidate genes by qPCR. Uterine health status was assigned to healthy (absence of abnormal vaginal discharge and ≤5 % PMN, n = 13), SE (absence of abnormal vaginal discharge and >5 % PMN, n = 30), and CE (mucopurulent or purulent vaginal discharge and >5 % PMN, n = 9). At the same time, a blood sample was collected to assess serum progesterone concentration and to categorize cows as low (≤1 ng/mL) or high (>1 ng/mL) in progesterone. High expression of IL1B, IL6, IL17A, CXCL8, PTGES, PTGS1, PTGS2, and INHBA genes and low expression of FST was noted in the endometrium of CE compared to healthy cows. Increased endometrial INHBA expression was observed in both SE and CE compared to healthy cows. Interestingly, greater expression of PTGES and PRXL2B genes and lower expression of PTGS2 were characteristic of SE versus CE or healthy. Among cows with no overt clinical symptoms of uterine disease (healthy and SE), the endometrial expression of IL1 B, CXCL8, and PTGES was greater in cows with high versus low serum progesterone. Several genes were differentially expressed among healthy, SE, and CE cows indicating different pathways for the development of different uterine diseases. In conclusion, we found progesterone-independent SE markers, which suggests that low endometrial PTGS2 expression may be indicative of an inadequate immune response and thus contribute to the pathogenesis of SE.

Prevalence of subclinical endometritis in dairy cows that recovered after treatment of clinical endometritis with cephapirin and PGF2α.

The aims of our study were to evaluate (1) the prevalence of subclinical endometritis (SE) in clinically cured cows after treatment of clinical endometritis (CE) with uterine cephapirin infusion or with systemic application of PGF2α and after self-healing, (2) the prevalence of SE in clinically cured cows in relation to the type of vaginal discharge. The study was conducted on 222 Polish Holstein Friesian cows with CE diagnosed by vaginoscopy and ultrasound. The animals were randomly allocated to one of three groups: Group 1 (n = 72): intrauterine cephapirin infusion; Group 2 (n = 73): single intramuscular injection of dinoprost; and Group 3 (n = 77): left untreated as a control. All cows were reexamined two weeks later (Exam 1). If there was still CE at this examination, these cows were treated using the same method as previously and were examined 2 weeks later (Exam 2). Cows still having CE at the second examination were examined two weeks later (Exam 3). Cows without signs of CE at Exams 1, 2 and 3 were considered cured, and endometrial samples from the uteri were collected by cytobrush to diagnose SE using cytological evaluation of PMN percentage. The threshold for SE was set at ≥ 5% PMNs. Two cows each from Groups 1 and 3 and three cows from Group 2 were not clinically recovered at Exam 3 and were excluded from the analysis. In total, SE was diagnosed in an average of 40.9% of clinically cured cows. The prevalence of SE in Group 1, 2 and 3 was 35.0%, 47.1% and 40.0%, respectively (p > 0.05). There were significantly higher (p < 0.05) SE cases after treatment of CE associated with purulent vaginal discharge than with mucopurulent discharge. In relation to the method of treatment, the prevalence of SE was significantly higher (p < 0.05) in cows treated with cephapirin with purulent vaginal discharge than with mucopurulent vaginal discharge. In conclusion, the study showed a high prevalence of SE in cows clinically cured after treatment of clinical endometritis with cephapirin or PGF2α and after self-healing. The prevalence of SE was significantly higher in cows with purulent vaginal discharge than with mucopurulent vaginal discharge. Therefore, in cows clinically recovered from clinical endometritis, the prevalence of SE should always be considered a negative consequence, and the resulting management of this uterine disease should be implemented at the herd level.

Occurrence of Zearalenone and Its Metabolites in the Blood of High-Yielding Dairy Cows at Selected Collection Sites in Various Disease States.

Zearalenone (ZEN) and its metabolites, alpha-zearalenol (α-ZEL) and beta-zearalenol (ß-ZEL), are ubiquitous in plant materials used as feed components in dairy cattle diets. The aim of this study was to confirm the occurrence of ZEN and its selected metabolites in blood samples collected from different sites in the hepatic portal system (posthepatic-external jugular vein EJV; prehepatic-abdominal subcutaneous vein ASV and median caudal vein MCV) of dairy cows diagnosed with mastitis, ovarian cysts and pyometra. The presence of mycotoxins in the blood plasma was determined with the use of combined separation methods involving immunoaffinity columns, a liquid chromatography system and a mass spectrometry system. The parent compound was detected in all samples collected from diseased cows, whereas α-ZEL and ß-ZEL were not identified in any samples, or their concentrations were below the limit of detection (LOD). Zearalenone levels were highest in cows with pyometra, where the percentage share of average ZEN concentrations reached 44%. Blood sampling sites were arranged in the following ascending order based on ZEN concentrations: EJV (10.53 pg/mL, 44.07% of the samples collected from this site), ASV (14.20 pg/mL, 49.59% of the samples) and MCV (26.67 pg/mL, 67.35% of the samples). The results of the study indicate that blood samples for toxicological analyses should be collected from the MCV (prehepatic vessel) of clinically healthy cows and/or cows with subclinical ZEN mycotoxicosis. This sampling site increases the probability of correct diagnosis of subclinical ZEN mycotoxicosis.

Prediction of Calving to Conception Interval Length Using Algorithmic Analysis of Endometrial mRNA Expression in Bovine.

After parturition, the uterus undergoes significant reconstruction, allows the endometrium to create an environment for subsequent embryo development. Here, we used an unsupervised algorithmic approach to select characteristic endometrial mRNA expression patterns of proposed markers and investigate each marker's role as an individual indicator of reproductive success. Clinically healthy cows at a sixth week postpartum were examined, the percentage of neutrophils (PMNs%) in the cytological smear was calculated, and an endometrial biopsy was taken for qPCR. Based on pregnancy examination, cows were divided into three groups: Pregnant before 100 days postpartum (P100, n = 11), pregnant between 100-200-day (P200, n = 14), and culled (C, n = 10). Animals were also classified based on two PMNs% thresholds > 5% PMNs and > 10% PMNs. The expression of IL1B, IL6, CXCL8, and IL17A was higher in >10%PMNs. The expression of PTGS1 was higher in the P200 compared to P100. Upregulation of inhibin A subunit (INHA) and downregulation of inhibin ß A subunit (INHBA) were observed in the P100. INHBA/INHA ratio was the most accurate linear predictor of the calving-to-conception interval. The application of the k-means algorithm allowed the identification of five unique expression patterns. The sensitivity and specificity of predicting allocation to P100 were 81% and 79%. We also documented the low efficiency of genes associated with subclinical endometritis and PMNs% in determining reproductive capability. These results suggested the presence of distinctive expression patterns in 6 weeks postpartum, correlated with cows' reproductive capacity. Furthermore, we proposed the INHBA/INHA ratio as an indicator of calving-to-conception interval length.

Endometrial mRNA expression of prostaglandin synthase enzymes PTGS 2, PTGFS and mPTGES 1 in repeat-breeding cows with cytologically determined endometritis.

Little is known about the inflammatory response of the endometrium in repeat-breeding cows with subclinical endometritis (SE). The objective of this study was to evaluate the mRNA expression of prostaglandin-endoperoxide synthase 2 (PTGS 2), prostaglandin F2α synthase (PTGFS) and prostaglandin E2 microsomal synthase 1 (mPTGES 1) in the endometrium of repeat-breeding cows with and without SE. SE was diagnosed cytologically using the cytobrush method, with the threshold being set at 5% polymorphonuclear neutrophils. Biopsy samples were obtained from the endometrium of repeat-breeding cows with SE (n = 10) and without SE (n = 10). The mRNA expression of the synthases was evaluated using qRT-PCR. Significantly higher (P < 0.05) expression of the PTGS 2 gene was detected in the repeat breeders with SE, whereas there was no significant difference in the expression of PTGFS and mPTGES 1 mRNAs between repeatbreeding cows with SE and those without it (P > 0.05). Our study confirms that increased endometrial expression of the PTGS 2 gene is involved in the inflammatory response in repeat breeders.

OvSynch Protocol and its Modifications in the Reproduction Management of Dairy Cattle Herds - an Update.

Current knowledge about the function of the reproductive tract and appropriate use of hormonal drugs affords control of the oestrus cycle of cows. One of the hormonal protocols is OvSynch, which enables artificial insemination (AI) to be performed at the precise optimum time without control of the ovaries and uterus. Use of such protocols in reproductive management allows oestrus cycles to be synchronised and cows to be effectively inseminated without oestrous detection, which is time-consuming and difficult in farms with numerous cows. Therefore, OvSynch has become the first management tool for AI and is an alternative method to heat detection. Over the 20 years since its first implementation, OvSynch has been modified many times to improve its reproduction outcomes and widen its use. Besides its original use for heat synchronisation, it is also used in many ovarian disorders as a therapeutic method. This review article describes the possibilities which OvSynch provides, its current modifications, various applications, and the advantages and disadvantages of its use in practice.

Secretion of prostaglandins and leukotrienes by endometrial cells in cows with subclinical and clinical endometritis.

The aims of this study were (1) to measure the secretion of prostaglandin F2α (PGF2α), prostaglandin E2 (PGE2), leukotriene B4 (LTB4), and leukotriene C4 (LTC4) by endometrial cells collected by a cytobrush from healthy cows and cows with subclinical and clinical endometritis in the fourth week postpartum, and (2) to evaluate the relationship between the mediators' levels of secretion and the number of polymorphonuclear neutrophils (PMNs) in the uterine smears of cows with subclinical endometritis. The study included cows without any signs of clinical endometritis (n = 63) and cows with clinical endometritis as a positive control (ENDOM, n = 12). Two different threshold ratios (>5% and >18% of PMNs) were used to categorize the cows without clinical signs as with or without cytologic endometritis (CE). Considering the first or second threshold, the animals with CE were included in group CE POS I or CE POS II, whereas the healthy cows were assigned to group CE NEG I or CE NEG II, respectively. The prevalence of CE was 68.25% (42/63) and 57.14% (36/63) according to the first and second thresholds, respectively. The highest level of secretion of all of the measured mediators occurred in the ENDOM group and differed significantly (P < 0.05) from the CE POS and CE NEG groups, regardless of the threshold. PGF2α secretion in the CE POS II group (1629 pg/mL) was significantly lower (P < 0.05) when compared with the CE NEG II group (2797 pg/mL), whereas there was no significant difference between the CE POS I and CE NEG I groups. PGE2 secretion differed between both groups with CE; higher concentrations were measured in the CE POS II group (6.68 ng/mL) when compared with the CE POS I (2.4 ng/mL) and CE NEG II (2.37 ng/mL) groups (P < 0.05). No significant differences were observed in the LTB4 and LTC4 secretion between the CE POS and CE NEG groups, considering both thresholds. It seems that CE does not fully mimic the inflammatory cascade associated with clinical signs. The response in the subclinical cases was limited to enhanced production of PGE2, which was particularly well-pronounced in cows with high numbers of PMNs (>18%) in the endometrial scrapings.

Activity of steroid sulphatase and estrogen sulphotransferase in the boar epididymis during the postpubertal period.

The activities of steroid sulphatase (StS) and estrogen sulphotransferase (EST) were determined in the epididymis of 18 boars. The animals were divided into three groups (n=6) according to age (8, 12 and 16 months). The boars were anesthetized and castrated. The tissue samples of different epididymal parts (caput, corpus and cauda) were taken and homogenized. Activities of StS and EST were assessed using (3)H-estrone sulphate ((3)H-E1S) and free (3)H-oestrone ((3)H-E1) as substrates, respectively. The substrate conversion rates after 60 min of incubation were 51.25% for (3)H-E1S and 45.65% for (3)H-E1. The activities of both enzymes were significantly higher in the caput epididymis compared to the cauda epididymis (p<0.05). A significant age-dependent increase of StS and EST activities (p<0.05) was observed. These results suggest that the availability of estrogens in the boar epididymis may be locally controlled also by StS and EST. The age-dependent increase of StS and EST activities may be related to the process of "biochemical maturation" of the reproductive system during the postpubertal period.