Metrisor: A novel diagnostic method for metritis detection in cattle based on machine learning and sensors.

The Metrisor device has been developed using gas sensors for rapid, highly accurate and effective diagnosis of metritis. 513 cattle uteri were collected from abattoirs and swabs were taken for microbiological testing. The Metrisor device was used to measure intrauterine gases. The results showed a bacterial growth rate of 75.75 % in uteri with clinical metritis. In uteri positive for clinical metritis, the most commonly isolated and identified bacteria were Trueperella pyogenes, Fusobacterium necrophorum and Escherichia coli. Measurements taken with Metrisor to determine the presence of metritis in the uterus yielded the most successful results in evaluations of relevant machine learning algorithms. The ICO (Iterative Classifier Optimizer) algorithm achieved 71.22 % accuracy, 64.40 % precision and 71.20 % recall. Experiments were conducted to examine bacterial growth in the uterus and the random forest algorithm produced the most successful results with accuracy, precision and recall values of 78.16 %, 75.30 % and 78.20 % respectively. ICO also showed high performance in experiments to determine bacterial growth in metritis-positive uteri, with accuracy, precision and recall values of 78.97 %, 77.20 % and 79.00 %, respectively. In conclusion, the Metrisor device demonstrated high accuracy in detecting metritis and bacterial growth in uteri and could identify bacteria such as E. coli, S. aureus, coagulase-negative staphylococci, T. pyogenes, Bacillus spp., Clostridium spp. and F. necrophorum with rates up to 80 %. It provides a reliable, rapid and effective means of detecting metritis in animals in the field without the need for laboratory facilities.

Postpartum infections and antimicrobial resistance of responsible pathogens in Ukraine: results a multicenter study (2020-2022).

OBJECTIVE: Aim: To determine the current prevalence of postpartum infections and antimicrobial resistance and antimicrobial resistance of responsible pathogens in Ukraine. PATIENTS AND METHODS: Materials and Methods: Multicenter prospective cohort study was conducted from January 2020 to December 2022 in fifteen hospitals from twelve regions of Ukraine. Definitions of healthcare- associated postpartum infection were adapted from the Centers for Disease Control and Prevention's National Healthcare Safety Network. Antibiotic susceptibility was done by the disc diffusion test as recommended by EUCAST. RESULTS: Results: Among 21,968 women, 6,175 (28.1%) postpartum infections were observed. Of all postpartum infection cases, 83.1% were detected after hospital discharge. The postpartum infection rates were 17.3% after cesarean section and 10.8% after vaginal delivery. The most common postpartum infection types were endometritis (17.3%), followed by urinary tract Infection (3.5%), mastitis (3.4%), surgical site infection (excluding endometritis) (2.4%), and episiotomy site infection (1.5%). The predominant postpartum infection pathogens in Ukraine were: Escherichia coli (10.4%), Enterococcus spp. (9.6%), Staphylococcus aureus (6.7%), Pseudomonas aeruginosa (5.8%), Enterobacter spp. (5.8%). In our study pathogens of postpartum infection had differently levels of resistance to antibiotics. CONCLUSION: Conclusions: Our results indicate that postpartum infections requiring medical attention are common in Ukraine and that most postpartum infections occur after hospital discharge, so that use of routine inpatient surveillance methods alone will lead to underestimation of postpartum infection rates. Optimizing the antibiotic prophylaxis may reduce the burden of postpartum infection, but prevention is the key element.

Streptococcus equi subsp. zooepidemicus: High molecular diversity of Argentinian strains isolated from mares with endometritis.

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) is a mucosal commensal of the lower genital tract in horses and is the most isolated bacterium causing endometritis in mares. The aim of this study was to determine the molecular diversity of S. zooepidemicus obtained from endometritis in mares in Buenos Aires province, Argentina. Thirty isolates obtained from the uterus of mares in 2005 and 2017 were studied. The MLST scheme was applied to identify the Argentinian genotypes and the clonal relationships and patterns of evolutionary descent were identified using the eBURST algorithm - goeBURST. Twenty six different Sequence types (STs) were identified, being only 11 of them previously reported in horses and also, from several host species and tissues. The other 15 STs were reported in Argentinian reproductive strains of mares in our study for the first time. The genotypes obtained from uterus in Argentina were not evenly distributed when all the published S. zooepidemicus STs were analysed, thus, it was not possible to establish that the same lineage circulates in our equine population. The fact that the identified genotypes were also reported in other countries, diverse samples and host species suggest that there is not a host, and an anatomical niche adaptation. Finally, the isolation of the same genotype in the vagina/clitoris and the uterus of the same mare highlights the versatility of S. zooepidemicus and its role as an opportunistic pathogen.

Changes in bacterial community composition in the uterus of Holstein cow with endometritis before and after treatment with oxytetracycline.

It is important to study the bacteria that cause endometritis to identify effective therapeutic drugs for dairy cows. In this study, 20% oxytetracycline was used to treat Holstein cows (n = 6) with severe endometritis. Additional 10 Holstein cows (5 for healthy cows, 5 for cows with mild endometritis) were also selected. At the same time, changes in bacterial communities were monitored by high-throughput sequencing. The results show that Escherichia coli, Staphylococcus aureus and other common pathogenic bacteria could be detected by traditional methods in cows both with and without endometritis. However, 16S sequencing results show that changes in the abundance of these bacteria were not significant. Endometritis is often caused by mixed infections in the uterus. Oxytetracycline did not completely remove existing bacteria. However, oxytetracycline could effectively inhibit endometritis and had a significant inhibitory effect on the genera Bacteroides, Trueperella, Peptoniphilus, Parvimonas, Porphyromonas, and Fusobacterium but had no significant inhibitory effect on the bacterial genera Marinospirillum, Erysipelothrix, and Enteractinococcus. During oxytetracycline treatment, the cell motility, endocrine system, exogenous system, glycan biosynthesis and metabolism, lipid metabolism, metabolism of terpenoids, polyketides, cofactors and vitamins, signal transduction, and transport and catabolism pathways were affected.

Molecular Mechanisms Associated with the Development of the Metritis Complex in Dairy Cattle.

The metritis complex (MC), a group of post-partum uterine diseases, is associated with increased treatment costs and reduced milk yield and fertility. The goal of this study was to identify genetic variants, genes, or genomic regions that modulate MC disease. A genome-wide association study was performed using a single-locus mixed linear model of 1967 genotypes (624,460 SNPs) and metritis complex records. Then, in-silico functional analyses were performed to detect biological mechanisms and pathways associated with the development of MC. The ATP8A2, COX16, AMN, and TRAF3 genes, located on chromosomes 12, 10, and 21, were associated with MC at p ≤ 0.0001. These genes are involved in the regulation of cholesterol metabolism in the stromal tissue of the uterus, which can be directly associated with the mode of transmission for pathogens causing the metritis complex. The modulation of cholesterol abundance alters the efficiency of virulence factors and may affect the susceptibility of the host to infection. The SIPA1L1, DEPDC5, and RNF122 genes were also significantly associated with MC at p ≤ 0.0001 and are involved in the PI3k-Akt pathway, responsible for activating the autophagic processes. Thus, the dysregulation of these genes allows for unhindered bacterial invasion, replication, and survival within the endometrium.

In vitro effects of different ozone preparations on microorganisms responsible for endometritis in the mare.

Infectious endometritis is considered one of the major causes of infertility and it can affect up to 60% of barren mares. It is characterized by the presence of one or more microorganisms in the reproductive tract and it is treated with the administration of antibiotics, ecbolic agents and uterine lavages. Ozone, thanks to its antimicrobial properties that are based on its high oxidative potential, could represent an effective alternative treatment for endometritis. The aim of this study was to test in vitro the bactericidal and fungicidal properties of different ozone formulations, either as gas (experiment 1) or dissolved in two liquid matrices (experiment 2), specifically distilled water or oil (Neozone 4000, Cosmoproject, Parma, Italy), onto 6 different species of microorganisms isolated from mares with clinical endometritis, namely Escherichia coli, Staphylococcus aureus, Streptococcus equi subsp. Zooepidemicus, Pseudomonas aeruginosa, Klebsiella pneumoniae and Candida albicans. In the first experiment, 3 clinical antibiotic-resistant strains per each species were exposed to different conditions: to O2O3 gas mixtures (15 and 40 µg/ml for 1, 3 and 5 min), to 100 % O2 or left untreated. The results showed a reduction of the microbial count of over 99,9% for every pathogen, time and concentration of O2O3 gas mixtures tested. Furthermore, gaseous ozone showed both a time-dependant effect (5 vs 3 vs 1 min of exposure) and a concentration-dependant effect (40 vs 15 µg/ml) at 1 and 3 min, while after 5 min no differences were observed. In the second experiment, minimum inhibitory concentration (MIC), and minimum bactericidal/fungicidal concentration (MBC, MFC) of ozonated distilled water and ozonated oil were evaluated. Ozonated oil showed a bactericidal/fungicidal activity against all the strains tested (MIC range 12.5-25 % v/v, MBC/MFC range 12.5-50 % v/v) while ozonated distilled water didn't show an observable antimicrobial effect, discouraging its use as an antimicrobial agent for the treatment of endometritis. The results of this in vitro study indicate that both gaseous ozone and ozonated oil exerted remarkable antimicrobial activities and are promising alternative treatments for infectious endometritis, even when caused by antibiotic-resistant bacteria, and encourage further experiments in an effort to scale down or even prevent the use of antibiotics in equine reproduction.

Microbial responses and changes in metabolic products in bovine uteri infected with Staphylococcus aureus.

There is mounting evidence that the uterine microbiota has an important role in the pathogenesis of endometritis, with invasion of pathogenic bacteria being a main cause of uterine microbial imbalance. However, mechanisms of uterine microbiota resistance to pathogen invasion remain unclear. In this study, an intrauterine infusion of Staphylococcus aureus was used as a bovine endometritis model; it significantly increased abundance of pathogenic bacteria (Streptococcus, Helccoccus, Fusobacterium, and Escherichia-Shigella) and significantly decreased abundance of probiotics (Allstipes, Bacteroides, Phascolarctobacterium, Romboutsia, and Prevotella). In addition, the metabolite aloe-emodin was positively correlated with Prevotella and based on combined analyses of omics and probiotics, the presence of its metabolite aloe-emodin in the uterus at least partially resisted Staphylococcus aureus invasion. Therefore, Aloe-emodin has potential for regulating microbial structure and preventing endometritis.

Incidence of uterine infections, major bacteria and antimicrobial resistance in postpartum dairy cows in southern Ethiopia.

BACKGROUND: Uterine infections, primarily caused by bacterial pathogens, pose a significant problem for dairy farmers worldwide, leading to poor reproductive performance and economic losses. However, the bacteria responsible for uterine infections have not been adequately studied, nor has the antibiotic susceptibility of the causative bacteria been frequently tested in Ethiopia. This study aims to estimate the cumulative incidence of uterine infections in postpartum dairy cows, identify bacterial causes and determine antimicrobial susceptibility profile of the isolated bacteria. METHODS: A prospective cohort study was conducted in which 236 cows from 74 dairy farms were monitored biweekly from calving to 90 days postpartum for metritis, endometritis and other disorders. Aseptic uterine swab samples were collected from 40 cows with uterine infections. The samples were cultured, and the isolated bacteria were tested for antimicrobial susceptibility using the disk diffusion method. RESULTS: Out of 236 cows monitored during the postpartum phase, 45 (19.1%) were found to have contracted uterine infection. The cumulative incidence of metritis was 11.4% (n = 27), while the cumulative incidence of endometritis was 7.6% (n = 18). Of the 40 cultured swab samples, 29 (72.5%) had one or more bacteria isolated. The most commonly isolated bacteria were Escherichia coli (45%), coagulase-positive staphylococci (30%), and Klebsiella spp. (22.5%). Other bacterial spp, including Arcanobacterium pyogenes (12.5%), Fusobacterium spp. (12.5%), Enterobacter aerogenes (12.5%), coagulase-negative staphylococci (12.5%), Streptococcus spp. (7.5%), Salmonella spp, (5%) Proteus spp (5%) and Pasteurella spp (2.5%) were also isolated. All of the isolated bacteria demonstrated resistance to at least one of the antimicrobials tested. Multidrug resistance was observed in E. coli, Klebsiella spp., A. pyogenes, and Fusobacterium spp. Gentamicin was found to be the most effective antimicrobial against all bacteria tested, while tetracycline was the least effective of all. CONCLUSION: The study found that a significant proportion of cows in the population were affected by uterine infections and the isolated bacteria developed resistance to several antimicrobials. The study emphasizes the need for responsible use of antimicrobials to prevent the emergence of antimicrobial resistance. It also highlights the importance of raising awareness among dairy farmers to avoid the indiscriminate use of antibiotics and its consequences.

Treatment of postpartum endometritis induced by multidrug-resistant bacterial infection in dairy cattle by green synthesized zinc oxide nanoparticles and in vivo evaluation of its broad spectrum antimicrobial activity in cow uteri.

Postpartum endometritis significantly affects the health and productivity of cattle, causing significant economic loss that is speculated to exceed billions of dollars annually. Treatment of postpartum endometritis, which is linked to various bacterial infections in the uterus after delivery and has an alarmingly high risk of antibiotic treatment failure for unidentified reasons, represents a great challenge. Several studies have demonstrated that various disease complications, such as multidrug-resistant (MDR) bacterial strains, prolonged infection treatment, and increased mortality risk, have emerged as a result of the extensive use of antibiotics to treat uterine infections and other microbial-related diseases. Recent research has led to the development of zinc oxide nanoparticles (ZnO NPs) that exhibit broad-spectrum antibacterial efficacy against bacterial pathogens, including MDR bacteria, without producing mutants that are resistant to zinc oxide (ZnO). In the present work, we biologically synthesized ZnO NPs from a green natural source of Helianthus annuus seeds for the treatment of endometritis caused by MDR bacterial strains in dairy cattle. We examined ZnO's potential as a substitute antimicrobial agent to treat cow endometritis by testing its ability to sustain potent antimicrobial activity against pathogenic bacteria, including Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), in cow uteri. Among uterine bacteria, ZnO significantly decreased E. coli and S. aureus, which are known pathogenic bacteria within the uterus and achieved a high cure rate that was associated with the induction of estrous and pregnancy. Taken together, our observations of ZnO's broad range of antibacterial activity in-vivo with an animal model and subsequent evaluations of its therapeutic efficacy in cows with endometritis shed light on its potential to be used as a substitute antimicrobial agent for the treatment of uterine illness.

Genesis of clinical and subclinical endometritis in dairy cows.

In brief: Clinical and subclinical endometritis are different manifestations of reproductive tract inflammatory disease in dairy cows. This review addresses the genesis of clinical and subclinical endometritis considering metabolic stress, innate immune dysfunction, and shifts in the composition of the uterine microbiota in the postpartum period. Abstract: Up to half of dairy cows may develop one or more types of reproductive tract inflammatory disease within 5 weeks after calving. Clinical endometritis (CE) results from uterine bacterial dysbiosis with increased relative abundance of pathogenic bacteria associated with luminal epithelial damage. These bacteria cause endometrial stromal cell lysis, followed by massive polymorphonuclear neutrophil (PMN) migration, and pyogenesis. CE is defined as endometrial inflammation accompanied by purulent discharge. Purulent discharge is not always accompanied by uterine inflammation (being (rarely) vaginitis or (commonly) cervicitis), hence referred to as purulent vaginal discharge (PVD). Subclinical endometritis (SCE) is an asymptomatic uterine disease defined by a threshold of PMN on cytology that is associated with worse reproductive performance; it has not been linked with bacterial dysbiosis. Current evidence suggests that SCE is a result of metabolic and inflammatory dysfunction that impairs innate immune function and the ability of endometrial PMN to undergo apoptosis, necrosis, and ultimately achieve resolution of inflammation. CE and SCE are diagnosed between 3 and 5 weeks postpartum and commonly overlap, but they are considered distinct manifestations of reproductive tract inflammatory disease. This review addresses the genesis of CE and SCE in postpartum dairy cows considering metabolic stress, innate immune dysfunction, and shifts in the composition of the uterine microbiota.

Analysis of the microbiota composition in the genital tract of infertile patients with chronic endometritis or endometrial polyps.

Background: The previous researches show that infertile patients have a higher incidence of endometritis and endometrial polyps, and the occurrence of these two diseases is related to changes in the microbiota of the genital tract. We aim to determine the composition and changing characteristics of the microbiota in the genital tract (especially the endometrium) of infertile patients with chronic endometritis or endometrial polyps, and find the correlation between it and the occurrence of diseases. Methods: This is a prospective study. We collected genital tract biopsy samples from 134 asymptomatic infertile patients receiving assisted reproductive therapy before embryo transfer. Through pathological examination and 16S ribosomal RNA(16S rRNA) sequencing, we determined the distribution of chronic endometritis and endometrial polyps in these patients, as well as their distribution of reproductive tract microorganisms. Results: Compared with the normal control group, the microbial group of reproductive tract in patients with chronic endometritis and endometrial polyps is changed, and there are significant species differences and relative abundance differences in the vagina, cervix and uterine cavity. Lactobacillus, the dominant flora of female genital tract, showed a change in abundance in patients with endometrial diseases. Endometrial microbiota composed of Staphylococcus, Gardnerella, Atopobium, Streptococcus, Peptostreptococcus, Chlamydia, Fusobacterium, Acinetobacter, etc. are related to chronic endometritis and endometrial polyps. Conclusion: The results showed that, compared with the normal control group, the endometrial microbiota of infertile patients with chronic endometritis or endometrial polyps did have significant changes in the relative abundance distribution of species, suggesting that changes in local microecology may be an important factor in the occurrence of disease, or even adverse pregnancy outcomes. The further study of endometrial microecology may provide a new opportunity to further improve the diagnosis and treatment strategy of chronic endometritis.

General and comparative aspects of endometritis in domestic species: A review.

Endometritis is a leading cause of sub- and infertility in domestic animal species. The healthy uterus is colonized by commensal bacteria, viruses and yeast/fungi that represent the nonpathogenic microbiota. A shift in the number or type of organisms accompanied by immune dysfunction, however, may trigger uterine infection and inflammation. Metritis is associated with inflammation of all uterine layers (endometrium, myometrium and perimetrium), whereas endometritis is a more superficial inflammation involving solely the endometrium. Endometritis generally occurs at two time points in domestic animal species, postpartum and postmating. Postpartum endometritis may chronically persist, either as a low-grade disease that often manifests as a vaginal discharge but not a systemic illness (in some species termed clinical endometritis) or sometimes subclinical where features are only detected by endometrial sampling. Contamination of the uterus at the time of mating occurs by direct deposition of semen (ejaculated or artificially inseminated) into the uterus. Improper drainage of the ejaculatory fluid or an inadequate immune response may result in persistent mating-induced endometritis. Both postpartum and postmating endometritis interferes with fertility by creating a suboptimal environment for embryo development and placentation, and chronic endometritis may have an impact on sperm survival and fertilization ability. In the postpartum animal, there may also be changes in milk production and maternal behaviour, which can affect offspring health and survival. Preventive strategies for endometritis largely depend on monitoring their known risk factors, which are sometimes specific with regard to the species. Effective, nonantibiotic therapy for endometritis is not available to date. Overall, extensive research has been performed in cattle and horses to unravel key aspects of endometritis, but in sows and bitches, the available literature is scant. Thus, the need and opportunity to investigate the condition vary considerably among domestic species and necessitate their comparative assessment. This article reviews general and comparative aspects of the diagnosis and classification, pathogenesis, preventive strategies and therapeutics of endometritis in domestic species with a specific focus on cows, mares, sows and bitches.

The emerging role of neutrophil extracellular traps in endometritis.

Endometritis is a kind of common obstetric disease in women, usually caused by various pathogenic bacteria. Neutrophil infiltration is one of the most important pathological features of endometritis. Neutrophils can reach the uterine cavity through the endometrium, and make early response to the infection caused by the pathogen. Neutrophil extracellular traps (NETs), a meshwork of chromatin fibers extruded by neutrophils, have a role in entrapping microbial pathogens. It has been confirmed that NETs have a strong antibacterial effect and play crucial roles in the occurrence and development of various diseases. However, while killing pathogenic bacteria, excessive NETs formation may cause immune damage to the body. NETs are present in endometrium of female domestic animals in different physiological periods, especially post-mating, postpartum and in the presence of lesions, especially in endometritis. Meanwhile, NETs and its products might contribute to a reduction in physical clearance and persistent endometritis. In brief, NETs is a double-edged sword and it may play a different role in the development of endometritis, which may be beneficial or harmful, and its specific mechanism needs further study. Here we provide an overview of the role of NETs in the development of endometritis and the regulatory role of selenium on NETs formation and endometritis.

The alteration of intrauterine microbiota in chronic endometritis patients based on 16S rRNA sequencing analysis.

BACKGROUND: Chronic endometritis (CE) is a disease of continuous and subtle inflammation occurring in the endometrial stromal area, which is often asymptomatic or present with non-specific clinical symptoms. METHODS: This study investigated the composition and distribution of the intrauterine microbiota of 71 patients who underwent hysteroscopy during the routine clinical inspection of infertility. Among them, patients who were diagnosed with chronic endometritis (CE) were allocated into CE group (n = 29) and others into non-CE group (n = 42). There was no significant difference in average age between the two groups (P = 0.19). Uterine flushing fluid was collected by the self-developed cervical trocar uterine cavity sampler and 16S rRNA sequencing was performed. RESULTS: The alpha diversity in the CE group was significantly higher than that in the non-CE group (P < 0.05). Firmicutes (newly named Bacillota) were the dominant phylum in the non-CE group (72.23%), while their abundance was much lower in the CE group (49.92%), but there was no statistically significant difference between the two groups. The abundances of Actinobacteriota and Cyanobacteria in the CE group were significantly higher than those in the non-CE group (P < 0.05). At the genus level, the abundance of Lactobacillus dominated in all samples, which presented a significantly lower abundance in the CE group (40.88%) than that in the non-CE group (64.22%) (P < 0.05). Correspondingly, the abundance of non-Lactobacillus was higher in the CE group, among which Pseudomonas and Cutibacterium increased significantly (P < 0.01). Moreover, compared with the non-CE group, the pathways involved in arginine and proline metabolism and retinol metabolism were significantly enriched in the CE group (P < 0.05), while the metabolism of lipid and prenyltransferases were significantly decreased in the CE group (P < 0.05). CONCLUSIONS: A certain microbial community was colonized in the uterine cavity, which was dominated by Lactobacillus. The structure and distribution of intrauterine microbiota in the CE group were different from those in the non-CE group by showing a lower abundance of Lactobacillus, and a significantly higher abundance of Pseudomonas and Cutibacterium. Additionally, the microbial metabolism was altered in the CE group. This study elaborated the alteration of intrauterine microbiota in CE patients, which may contribute to the diagnosis of CE and provide a reference for antibiotic treatment of CE.

Chronic endometritis - is it time to clarify diagnostic criteria?

Chronic endometritis is a persistent, low-intensity inflammation of endometrial mucosa, characterized by the infiltration of plasma cells into the endometrial stroma This immunological alteration is thought to be a consequence of a bacterial infection. For a long time, chronic endometritis was poorly investigated and rarely considered in clinical practice because it is either asymptomatic or presents with no specific symptoms. Its association with adverse effects on fertility and retrospectively reported effectiveness of antibiotic treatment were the main reasons for a growing interest in this endometrial pathology. Chronic endometritis is now a hot topic in recurrent pregnancy loss and recurrent implantation failure research. Nevertheless, there are still no recommendations to include chronic endometritis investigation in a clinical evaluation of infertile patients. The uncertain role of this condition is an effect of significant differences in study results presented by different research groups. One important reason for these inconsistent findings is a lack of standardised chronic endometritis diagnostic methods. We present a review of the literature, focusing on the currently available chronic endometritis diagnostic techniques. The review is subdivided into three parts concerning the diagnostic accuracy of three main diagnostic modalities. Histopathological examination of endometrial tissue, hysteroscopic evaluation of uterine cavity and identification of the bacterial factor. In conclusion, it is of great importance to establish a consensus on the diagnostic criteria for chronic endometritis. This is the only way to enhance international cooperation and create well-design multicenter studies to evidence the role of this endometrial pathology in infertility.

Paeniclostridium sordellii-associated peripartum metritis in goats.

Paeniclostridium sordellii is involved in enteric and histotoxic infections in several animal species. In humans, P. sordellii has been linked to gynecological disease, an association not previously investigated in animals. To unveil a potential association of P. sordellii with veterinary reproductive disease, a retrospective search of the database of the California Animal Health and Food Safety Laboratory System (1990-2020) was conducted and identified 9 cases of goats with P. sordellii-associated metritis or endometritis that were confirmed by immunofluorescence antibody test and/or bacterial isolation, and often co-colonized by Escherichia coli. Six of 9 does were also copper deficient. Polymerase chain reaction (PCR) on formalin-fixed, paraffin-embedded uterine tissue identified the sordellilysin gene in all 9 cases, and the lethal toxin gene in 4. Our findings suggest goats could be predisposed to P. sordellii-associated endometritis/metritis and toxemia when co-infected with E. coli. The role of mineral deficiencies influencing vulnerability to puerperal bacterial infections in goats is possible but remains undetermined. To our knowledge, this is the first report documenting the association of P. sordellii with veterinary gynecological disease.

Bayesian accuracy estimates and fit for purpose thresholds of cytology and culture of endometrial swab samples for detecting endometritis in mares.

The overall aim of this work was to identify the potential impact of misclassification errors associated with routine screening and diagnostic testing for endometritis in mares. Using Bayesian latent class models (BLCM), specific objectives were to: 1) estimate the diagnostic accuracy of cytology and culture of endometrial swab samples to detect endometritis in mares; 2) assess the impact of different cytology thresholds on test accuracy and misclassification costs; and 3) assess the sensitivity (Se) and specificity (Sp) of a diagnostic strategy including both tests interpreted in series and parallel. Diagnostic and pre-breeding endometrial swab samples collected from 3448 mares based at breeding premises located in the South East of England between 2014 and 2020 were retrospectively analysed. Culture results were classified as positive according to three different case definitions: (A) > 90% of the growth colonies were a monoculture; (B) pathogenic or pathogenic and non-pathogenic bacteria were identified; and (C) any growth was observed. Endometrial smears were graded based on the percent of polymorphonuclear cells (PMN) per high power field (HPF). A hierarchical BLCM was fitted using the cross-tabulated results of the three culture case definitions with a cytology threshold fixed at > 0.5% PMN. Fit for purpose cytology thresholds were proposed using a misclassification cost analysis in the context of good antimicrobial stewardship and for varying endometritis prevalence estimates. Median [95% Bayesian credible intervals (BCI)] cytology Se estimates were 6.5% (2.2-11.6), 6.4% (2.2-10.8) and 6.3% (2.2-10.8) for scenario A, B and C, respectively. Median (95% BCI) cytology Sp estimates were 88.8% (83.1-94.8), 88.9% (83.9-93.8) and 88.8% (84.0-93.8) for scenarios A, B and C, respectively. Median (95% BCI) culture Se estimates were 37.5% (29.9-46.0), 42.3% (33.8-51.1) and 46.4% (35.7-55.9) for scenarios A, B and C, respectively. Median (95% BCI) culture Sp estimates were 92.8% (84.3-99.0), 91.5% (82.5-98.0) and 90.8% (80.1-97.4) for scenarios A, B and C, respectively. Regardless of the culture case definition, Se and Sp of cytology (> 0.5% PMN) was lower than previously reported for swab samples in studies using histology as the reference standard test. The misclassification cost term decreased as the cytology threshold increased for all scenarios and all prevalence contexts, suggesting that, regardless of the endometritis prevalence in the population, increasing the cytology threshold would reduce the misclassification costs associated with false positive mares contributing to good antimicrobial stewardship.

Effect of calving season on metritis incidence and bacterial content of the vagina in dairy cows.

Heat stress and uterine diseases, including metritis and endometritis, both reduce milk yields and reduce reproductive performance. Bacterial growth is promoted by elevated temperature while heat stress reduces host immune cell function, but it is not known whether increased environmental temperature promotes uterine disease by altering host immunity or bacterial growth. We hypothesize that seasonal variations in environmental temperature influence metritis incidence in the dairy cow independent of bacterial prevalence in the reproductive tract. To investigate how environmental temperature may impact metritis incidence, records of 3507 calvings in Florida over a 5-year period were evaluated. The incidence of metritis increased from 21.1% in the cool season (October through March) to 24.2% during the warm season (April through September, P < 0.05). To elucidate a link between environmental temperature and uterine disease, 102 cows were enrolled during the warm season (September 2017; n = 51) and cool season (February-March 2018; n = 51). Cows were maintained on pasture during the dry period and moved to free stall barns with fans and water soakers immediately prior to calving and remained in that environment after calving. Vaginal mucus was collected and scored on days 7 (to evaluate metritis) and 21 (to evaluate endometritis) postpartum to evaluate the incidence of uterine disease and quantify bacterial content and species using qPCR. Daily milk yield for the first 60 DIM was reduced during the warm season compared with the cool season (32.6 ± 1.62 vs 37.23 ± 1.60 kg, P < 0.05) consistent with effects of prepartum heat stress. Interestingly, more cows had persistent uterine disease on both d 7 and d 21 in the warm season compared with the cool season (58.0 vs 29.4%, P < 0.05). Regardless of calving season the total bacterial content in the vagina was greater on d 7 compared to d 21. While metritis incidence was increased in the warm season, the vaginal content of total bacteria, Escherichia coli, Trueperella pyogenes, Fusobacterium necrophorum and Prevotella melaninogenica were similar during the cool season and the warm season. Our data suggests that prepartum heat stress related to season of calving increased the incidence of metritis and persistence of uterine disease in the dairy cow independent of vaginal bacteria content. The possibility that prepartum heat stress perturbs host immune function and increases the risk of metritis when cows are exposed to an equivalent number of pathogenic bacteria requires further investigation.

Physiological characterisation of Corynebacterium uterequi associated with pregnancy complications in mares.

Increasing cases of equine infertility and early embryonic loss in the Western Cape, South Africa, were documented in recent years. These appeared to be associated with Corynebacterium uterequi isolated from the uteri of infected mares. The purpose of this study was, therefore, to investigate the physiology and potential pathogenicity of this bacterium. Histopathological analyses were conducted on five mares suffering from reproductive complications, and from which Corynebacterium strains were detected on culture of uterine swabs. The histopathology revealed that the mares suffered from various forms of endometritis, suggesting a potential role of Corynebacterium strains in the disease. An isolate from one of the biopsies, and 11 other tentatively identified C. uterequi isolates from the urogenital tracts of other mares, which all had a history of pregnancy complications, were subsequently identified using molecular techniques and characterised based on environmental stress tolerance, enzyme profiles, antibiotic susceptibility and ability to form biofilms. It was found that representatives of C. uterequi possessed several virulence-associated characteristics, including trypsin and urease activity, as well as the ability to form weakly adherent monoculture biofilms. Several isolates displayed resistance to trimethoprim-sulfamethoxazole. In conclusion, this study provided some insight into the general physiology and pathogenic potential of C. uterequi, and points to the possible role of C. uterequi in the onset of equine pregnancy complications. Moreover, the ability to form biofilms suggests the potential for chronic infection, which was observed in 60% of the mares. Further research, however, is needed to implicate C. uterequi as an equine pathogen.

An in vitro comparison of antimicrobial efficacy and cytotoxicity between povidone-iodine and chlorhexidine for treating clinical endometritis in dairy cows.

This study aimed to assess the in vitro antimicrobial effects of chlorhexidine (CHX) and povidone-iodine (PI) on clinical isolates of Escherichia coli (E. coli) and Trueperella pyogenes (T. pyogenes) from the vaginal discharge of dairy cows, as well as to compare the cytotoxicity effects of CHX and PI on bovine endometrial epithelial cells (BEnEpC). In Experiment 1, 12 E. coli and 10 T. pyogenes were isolated from the vaginal discharge of cows with a uterine infection. The MIC and MBC against CHX and PI were analyzed in vitro. In Experiment 2, the cytotoxicity effects of CHX and PI on BEnEpC were analyzed using a Viability/Cytotoxicity Kit, wound scratch healing assay, and the expression of pro-inflammatory cytokine genes (IL-6, IL-8, and TNF-α). In Experiment 1, the MIC and MBC values of CHX against E. coli were 0.0002% and 0.0002 to 0.00025%, respectively. The MIC and MBC values of PI were 1.25 to 2.5% and 1.25 to 5%, respectively. For T. pyogenes, the MIC and MBC values of CHX were 0.00002%. The MIC and MBC values of PI were 1.25%. In Experiment 2, the cell viability significantly decreased, and wound closures were significantly inhibited after treatment with ≥ 0.002% CHX and ≥ 0.025% PI. The expression of IL-6, IL-8, and TNF-α significantly increased after treatment with PI. Only IL-6 showed a significant increase after cells were treated with 0.00002% and 0.0002% CHX. The results suggested that both CHX and PI had high antibacterial effects. However, veterinarians and farmers should be aware of their cytotoxicity, which decrease viability of endometrial epithelial cells and inhibit wound healing in vitro.