Apparent prevalence and risk factors for udder skin diseases and udder edema in Bavarian dairy herds.

The objective of this cross-sectional study was to assess the prevalence and risk factors for teat warts, udder edema, udder thigh dermatitis, and udder cleft dermatitis on Bavarian dairy farms. Udder health and hygiene scores of lactating cows were recorded on 152 farms in Bavaria, Germany. Management practices (e.g., housing, milking systems, and feeding regimens) were assessed with a comprehensive questionnaire. Adjusted prevalence estimates were determined using regression analysis with herd as the random effect. Mann-Whitney U or Fisher's exact on herd level and regression analyses on cow level were performed to determine risk factors. Of the 6,208 cows examined, 4.0% had teat warts, 1.1% udder edema, 0.2% udder thigh dermatitis, and 0.3% udder cleft dermatitis. The apparent median within-herd prevalence was less than 4% for all 4 diseases. Herd-level factors that were associated with the presence of teat warts on a farm were the proportion of cows with poor teat ends as well as conventional milking systems compared with milking robots. At a cow level, teat warts were associated with high somatic cell counts. Herds with poor depth (<5 cm) of bedding material and cows with days in milk less than 60 d had increased odds for udder edema. First-lactating cows had higher odds for udder thigh dermatitis. Freestall housing and comfort rubber mats were identified as risk factors for udder cleft dermatitis on a herd level. In conclusion, although most nonmastitis udder diseases were rarely observed in this study, some herd management practices and cow factors were associated with their presence on a farm or cow level. Future studies are needed to further investigate risk factors for each disease in more detail.

Identifying poor metabolic adaptation during early lactation in dairy cows using cluster analysis.

Currently, cows with poor metabolic adaptation during early lactation, or poor metabolic adaptation syndrome (PMAS), are often identified based on detection of hyperketonemia. Unfortunately, elevated blood ketones do not manifest consistently with indications of PMAS. Expected indicators of PMAS include elevated liver enzymes and bilirubin, decreased rumen fill, reduced rumen contractions, and a decrease in milk production. Cows with PMAS typically are higher producing, older cows that are earlier in lactation and have greater body condition score at the start of lactation. It was our aim to evaluate commonly used measures of metabolic health (input variables) that were available [i.e., blood ß-hydroxybutyrate acid, milk fat:protein ratio, blood nonesterified fatty acids (NEFA)] to characterize PMAS. Bavarian farms (n = 26) with robotic milking systems were enrolled for weekly visits for an average of 6.7 wk. Physical examinations of the cows (5-50 d in milk) were performed by veterinarians during each visit, and blood and milk samples were collected. Resulting data included 790 observations from 312 cows (309 Simmental, 1 Red Holstein, 2 Holstein). Principal component analysis was conducted on the 3 input variables, followed by K-means cluster analysis of the first 2 orthogonal components. The 5 resulting clusters were then ascribed to low, intermediate, or high PMAS classes based on their degree of agreement with expected PMAS indicators and characteristics in comparison with other clusters. Results revealed that PMAS classes were most significantly associated with blood NEFA levels. Next, we evaluated NEFA values that classify observations into appropriate PMAS classes in this data set, which we called separation values. Our resulting NEFA separation values [<0.39 mmol/L (95% confidence limits = 0.360-0.410) to identify low PMAS observations and ≥0.7 mmol/L (95% confidence limits = 0.650-0.775) to identify high PMAS observations] were similar to values determined for Holsteins in conventional milking settings diagnosed with hyperketonemia and clinical symptoms such as anorexia and a reduction in milk yield, as reported in the literature. Future studies evaluating additional clinical and laboratory data, breeds, and milking systems are needed to validate these finding. The aim of future studies would be to build a PMAS prediction model to alert producers of cows needing attention and help evaluate on-farm metabolic health management at the herd level.

Determinants of compliance with infection prevention measures by physicians: a scoping review.

Despite evidence that application of infection prevention measures can reduce healthcare-associated infections, compliance with these measures is low, especially among physicians. Intervention effects often do not sustain. An overview of determinants for physicians' infection prevention behaviour and successful behaviour change strategies is lacking. The aim of this review was to identify what determinants influence physicians' infection prevention behaviour, what strategies to improve compliance have been explored, and whether theories, models, and frameworks from implementation science have been used in these studies. A literature search was performed in PubMed, Embase, APA PsycInfo and Web of Science up to June 2nd, 2023, in collaboration with a medical information specialist. All study types focusing on infection prevention behaviour of physicians in high-income countries were included. Data on determinants and strategies was extracted; determinants were categorized into the Theoretical Domains Framework (TDF). Fifty-six articles were included. The TDF domains 'environmental context and resources', 'social influences', 'beliefs about consequences', 'memory, attention and decision-making', 'knowledge', and 'skills' were found most relevant. The prevailing determinant covers a theme outside the TDF: socio-demographic factors. Sustainable interventions are multimodal approaches that at least include feedback, education, and a champion. Theories, models, and frameworks have rarely been used to guide implementation strategy development. In conclusion, it was found that intervention studies rarely specify the determinants that they aim to address and they lack theoretical underpinning. Future initiatives should combine knowledge about determinants with implementation science to develop theory-based interventions tailored to determinants.

Prevalence of extended-spectrum ß-lactamase-producing Escherichia coli on Bavarian dairy and beef cattle farms.

Extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli strains are believed to be widely distributed among humans and animals; however, to date, there are only few studies that support this assumption on a regional or countrywide scale. Therefore, a study was designed to assess the prevalence of ESBL-producing E. coli in dairy cows and beef cattle in the southern part of Bavaria, Germany. The study population included 30 mixed dairy and beef cattle farms and 15 beef cattle farms. Fecal samples, boot swabs, and dust samples were analyzed for ESBL-producing E. coli using selective media. PCR was performed to screen for CTX-M and ampC resistance genes. A total of 598 samples yielded 196 (32.8%) that contained ESBL-producing E. coli, originating from 39 (86.7%) of 45 farms. Samples obtained from mixed farms were significantly more likely to be ESBL-producing E. coli positive than samples from beef cattle farms (fecal samples, P < 0.001; boot swabs, P = 0.014; and dust samples, P = 0.041). A total of 183 isolates (93.4%) of 196 ESBL-producing E. coli-positive strains harbored CTX-M genes, CTX-M group 1 being the most frequently found group. Forty-six additional isolates contained ampC genes, and 5 of the 46 isolates expressed a blaCMY-2 gene. The study shows that ESBL-producing E. coli strains are commonly found on Bavarian dairy and beef cattle farms. Moreover, to our knowledge, this is the first report of the occurrence of blaCMY-2 in cattle in Germany.

Strategies to improve the implementation of infection control link nurse programmes in acute-care hospitals.

BACKGROUND: Infection control practitioners face several challenges when implementing infection control link nurse (ICLN) programmes. Identification of strategies to address these can improve the impact of current ICLN programmes and guide their future implementation. AIM: We aimed to identify implementation strategies for ICLN programmes in acute-care hospitals with the Consolidated Framework for Implementation Research (CFIR)-Expert Recommendations for Implementing Change (ERIC) Implementation Strategy Matching tool. METHODS: An expert panel matched 19 implementation and sustainment barriers, identified in our previous studies, to the most fitting CFIR constructs. Subsequently, we applied the CFIR-ERIC Matching Tool and generated a list of implementation strategies to address these barriers. FINDINGS: Barriers were predominantly found within the CFIR domains 'inner setting' (characteristics of the implementing organization) and 'process' (stages of implementation). With the ERIC Matching Tool, we identified the 10 most important strategies to address barriers of implementation of ICLN programmes: identify and prepare champions, conduct local consensus discussions, assess for readiness and identify barriers and facilitators, inform local opinion leaders, use facilitation, create a learning collaborative, conduct local needs assessments, develop a formal implementation blueprint, build a coalition, and identify early adopters. CONCLUSION: The CFIR domains 'inner setting' and 'process' appeared to be the most important to impede implementation of ICLN programmes in acute-care hospitals. Application of the CFIR-ERIC tool highlighted the identification and preparation of champions as the leading strategy for the successful implementation of these programmes. With this tool, strategies can be specifically tailored towards local implementation and sustainment barriers.

Full model selection using regression trees for numeric predictions of biomarkers for metabolic challenges in dairy cows.

Dairy cows suffer poor metabolic adaptation syndrome (PMAS)1 during early post-calving periods caused by negative energy balance. Measurement of blood beta-hydroxy butyric acid (BHBA)2 and blood non-esterified fatty acids (NEFA)3 allow early and accurate detection of negative energy balance. Machine learning prediction of blood BHBA and blood NEFA using milk testing samples represents an opportunity to identify at-risk animals, using less labor than direct blood testing methods. Routine milk testing on modern dairies and computer record keeping provide an immense amount of data which can then be used in machine learning models. Previous research for predicting blood metabolites using Fourier-transform infrared spectroscopy (FTIR)4 milk data has focused mainly on individual models rather than a comparison among the models. Full model selection is the process of comparing different combinations of pre-processing methods, variable selection, and statistical learning algorithms to determine which model results in the lowest prediction error for a given dataset. For this project we used a full model selection approach with regression trees (rtFMS)5 . rtFMS uses the cross-validated performance of different model configurations to feed a regression tree for selecting a final model. A total of 384 possible model configurations (algorithms, predictors and data preprocessing options) for each outcome (blood BHBA and blood NEFA) were considered in the rtFMS technique. rtFMS allows direct comparison of multiple modeling approaches reducing bias due to empirical knowledge, modeling habits, or preferences, identifying the model with minimal root mean squared prediction error (RMSE)6 . An elastic net regression model was selected as the best performing model for both biomarkers. The input data for blood BHBA predictions were FTIR milk spectra, with a second derivative pre-processing, and a filter with 212 wave numbers, obtaining RMSE = 0.354 (0.328-0.392). The best performing model for blood NEFA had input data of FTIR milk spectra, with a second derivative pre-processing, and a filter with 212 wave numbers filter along with the time of milking, obtaining RMSE = 0.601 (0.564-0.654). The comparison of multiple modeling strategies, conducted by rtFMS, present an option for improved FTIR prediction models of blood BHBA and blood NEFA by reducing error due to human bias. The implementation of rtFMS to design future prediction models can guide model inputs and features. Our prediction models have the potential to increase early detection of metabolic disorders in dairy cows during the transition period.

Evaluation of the DiversiLab system for detection of hospital outbreaks of infections by different bacterial species.

Many bacterial typing methods are specific for one species only, time-consuming, or poorly reproducible. DiversiLab (DL; bioMérieux) potentially overcomes these limitations. In this study, we evaluated the DL system for the identification of hospital outbreaks of a number bacterial species. Appropriately typed clinical isolates were tested with DL. DL typing agreed with pulsed-field gel electrophoresis (PFGE) for Acinetobacter (n = 26) and Stenotrophomonas maltophilia (n = 13) isolates. With two exceptions, DL typing of Klebsiella isolates (n = 23) also correlated with PFGE, and in addition, PFGE-nontypeable (PFGE-NT) isolates could be typed. Enterobacter (n = 28) results also correlated with PFGE results; also, PFGE-NT isolates could be clustered. In a larger study (n = 270), a cluster of 30 isolates was observed that could be subdivided by PFGE. The results for Escherichia coli (n = 38) correlated less well with an experimental multilocus variable number of tandem repeats analysis (MLVA) scheme. Pseudomonas aeruginosa (n = 52) showed only a limited number of amplification products for most isolates. When multiple Pseudomonas isolates were assigned to a single type in DL, all except one showed multiple multilocus sequence types. Methicillin-resistant Staphylococcus aureus generally also showed a limited number of amplification products. Isolates that belonged to different outbreaks by other typing methods, including PFGE, spa typing, and MLVA, were grouped together in a number of cases. For Enterococcus faecium, the limited variability of the amplification products obtained made interpretation difficult and correlation with MLVA and esp gene typing was poor. All of the results are reflected in Simpson's index of diversity and adjusted Rand's and Wallace's coefficients. DL is a useful tool to help identify hospital outbreaks of Acinetobacter spp., S. maltophilia, the Enterobacter cloacae complex, Klebsiella spp., and, to a somewhat lesser extent, E. coli. In our study, DL was inadequate for P. aeruginosa, E. faecium, and MRSA. However, it should be noted that for the identification of outbreaks, epidemiological data should be combined with typing results.

Prediction model optimization using full model selection with regression trees demonstrated with FTIR data from bovine milk.

Predictive modeling is the development of a model that is best able to predict an outcome based on given input variables. Model algorithms are different processes that are used to define functions that transform the data within models. Common algorithms include logistic regression (LR), linear discriminant analysis (LDA), classification and regression trees (CART), naïve Bayes (NB), and k-nearest neighbor (KNN). Data preprocessing option, such as feature extraction and reduction, and model algorithms are commonly selected empirically in epidemiological studies even though these decisions can significantly affect model performance. Accordingly, full model selection (FMS) methods were developed to provide a systematic approach to select predictive modeling methods; however, current limitations of FMS, such as its dependency on user-selected hyperparameters, have prevented their routine incorporation into analyses for model performance optimization. Here we present the use of regression trees as an innovative method to apply FMS. Regression tree FMS (rtFMS) requires the development of a model for every combination of predictive modeling method options under consideration. The iterated, cross-validation performances of these models are then passed through a regression tree for selection of a final model. We demonstrate the benefits of rtFMS using a milk Fourier transform infrared spectroscopy dataset, wherein we build prediction models for two blood metabolic health parameters in dairy cows, nonesterified fatty acids (NEFA) and ß-hydroxybutyrate acid (BHBA). The goal for building NEFA and BHBA prediction models is to provide a milk-based screening tool for metabolic health in dairy cattle that can be incorporated automatically in milk analysis routines. These models could be used in conjunction with physical exams, cow side tests, and other indications to initiate medical intervention. In contrast to previously reported FMS methods, rtFMS is not a black box, is simple to implement and interpret, it does not have hyperparameters, and it illustrates the relative importance of modeling options. Additionally, rtFMS allows for indirect comparisons among models developed using different datasets. Finally, rtFMS eliminates user bias due to personal preference for certain methods and rtFMS removes the dependency on published comparisons of methods. Thus, rtFMS provides clear benefits over the empirical selection of data preprocessing options and model algorithms.

[The intradermal tuberculin test: literature, directive and implementation in practice]. / Der Tuberkulin-Hauttest: Literatur, Richtlinie und Umsetzung in der Praxis.

OBJECTIVE: Because of an increase in the number of cases of bovine tuberculosis in southern Germany (Allgäu region, mainly in the administrative district Swabia) during recent years, blanket tuberculosis testing was resumed in this region. The aim of this study was to review the veterinarians' current knowledge regarding the technique of the intradermal tuberculin test. As a consequence, a guide with precise instructions for the execution and interpretation of intradermal tuberculin testing in cattle based on the current legislation should be created. MATERIAL AND METHODS: Using a questionnaire, farm-animal practitioners' knowledge and experiences of intradermal tuberculin testing were surveyed, collected and evaluated. Legislative texts on tuberculosis (particularly testing of tuberculosis) were evaluated in their current and previous versions, and compared with the experiences reported by the veterinarians. RESULTS: A total of 137 veterinarians participated and 130 returned questionnaires could be evaluated. Forty-four of the 130 participants were involved in tuberculosis testing when the survey was performed. Of these 44 questionnaires, 42 were incorporated in the final evaluation. The majority of the veterinarians perform the intradermal tuberculosis test as laid down in the Commission Regulation (EC) no. 1226/2002 of 8 July 2002 amending Annex B to Council Directive 64/432/EEC. However, many practitioners do not comply with the requirements of the Commission Regulation (EC) no. 1226/2002 when evaluating the results of the intradermal tuberculosis test. Veterinarians showing the least accordance with required standards only test single animals or work in areas other than Swabia. CONCLUSIONS: In areas severely affected by tuberculosis, the technique of intradermal tuberculosis testing is performed almost as demanded by the Commission Regulation (EC) no. 1226/2002. However, a more uniform and careful approach should be sought when monitoring the results. The guide designed in the context of this study can help to improve the performance of the intradermal tuberculosis test. The information from the literature review also shows that there is currently no standardized method of intradermal tuberculosis testing.

[The use of an externally derived fetal electrocardiogram in obstetrical diagnosis in cattle for the evaluation of fetal vitality]. / Untersuchungen zur Anwendung eines extern abgeleiteten fetalen Elektrokardiogramms in der geburtshilflichen Diagnostik beim Rind zur Vitalitätseinschätzung des Fetus.

In 33 pregnant cows a fetal electrocardiogram (ECG) using an external lead was recorded during second stage of labor. A curve of the fetal heart rate pattern was drawn which served to determine the following parameters: basal heart rate, and amplitude as well as frequency of heart rate oscillation. These parameters were compared with APGAR scoring, colostrum intake, blood gas analysis as to their value for evaluation of vitality. There was a statistically positive correlation between basal heart rate during birth and base deficit after birth. Basal heart rate was negatively correlated with plasma pH measured after fetal expulsion. Amplitude of heart rate oscillation was negatively correlated with pH in plasma and concentration of standard bicarbonate, and was positively correlated with carbon dioxide pressure and base deficit. Calves with acidosis at birth or decreased colostrum intake had statistically significantly higher amplitudes of oscillation than healthy control calves. Basal heart rate of the fetus when used as the only parameter might not be suitable in order to exactly evaluate fetal vitality. In contrast, amplitude of heart rate oscillation more reliably indicated a disturbance of fetal condition. Under practical conditions, the described procedure of measuring fetal ECG is suitable in order to detect a viable fetus.

[Model of an information system for veterinary fertility monitoring as part of an integrated herd management system]. / Modell eines EDV-Systems zur tierärztlichen Fruchtbarkeitsüberwachung als Teil einer integrierten Herdenbetreuung.

The requirements of the veterinarian's work are changing by reason of an increasing intensity of dairy industry. The model of an information system for monitoring and managing dairy herd health and management system is described. General and special requirements are illustrated. The program requires urgent development for the use of veterinarians and herd owners, including the provision of a data communication link to a veterinary-agricultural information system. The system should integrate the veterinarians into the animal production in order to improve herd health and to secure the veterinarian's role in, and facilitate the development of novel scientific approaches to, dairy herd health and management.

[The effect of gonadotropin releasing hormone (GnRH) and analogs on the conception rate in cattle. A critical literature review]. / Zum Einfluss von Gonadotropin Releasing Hormon (GnRH) und Analogen auf die Konzeptionsrate beim Rind. Eine kritische Literaturübersicht.

The objective of this article was to review the current literature of the influence of gonadotropin releasing hormone (GnRH) and GnRH agonists on conception rate in dairy cattle. The application of GnRH or agonists at artificial insemination (first and subsequent) and between days 7 and 34 after parturition were considered. The variations between studies were discussed as well as different mechanisms concerning the influence of GnRH for establishing pregnancy. From a critical point of view the routine use of GnRH or agonists at the time of first or subsequent breeding or during the postpartum period cannot be supported.

Occurrence of zoonotic clostridia and Yersinia in healthy cattle.

Zoonotic pathogens are a frequent cause of disease worldwide. This study was designed to determine the occurrence of Clostridium difficile, Clostridium botulinum, and Yersinia enterocolitica in cattle in southern Bavaria, Germany. The study population included 49 farms; 34 were dairy farms (30 also fattening beef cattle) and 15 were solely beef cattle farms. Fecal and dust samples were collected from summer 2011 to summer 2012 and analyzed using a combination of enrichment procedures and real-time PCR. For the detection of C. difficile, samples were screened for the presence of the tpi gene and toxin genes tcdA, tcdB, and cdtA. Samples also were screened for genes for C. botulinum toxins A through F and for the ail gene of Y. enterocolitica. Of 506 samples, C. difficile genes were found in 29 samples (5.7%): 25 samples from dairy farms and 4 samples from beef cattle farms. Toxin genes were identified in 17 samples, with toxigenic profiles of A(+)B(+)CDT(-), A(+)B(-)CDT(+), and A(+)B(+)CDT(+). C. botulinum toxin genes were not detected in fecal samples from cattle, but the gene for toxin B was detected in 1 (0.8%) of 125 dust samples. Y. enterocolitica genes were found in 6 (1.6%) of 382 fecal samples from three dairy farms and one beef cattle farm. This study revealed that C. difficile and Y. enterocolitica are rare on cattle farms in Bavaria, Germany. In contrast to results of previous studies, C. botulinum was not detected in fecal samples but was found very rarely in dust samples from the cattle environment.

[Effects of dry period length on milk production, health, fertility, and quality of colostrum in dairy cows. Invited review]. / Auswirkungen der Länge der Trockenstehzeit bei Milchkühen auf Leistung, Gesundheit, Fruchtbarkeit und Kolostrumqualität.

In terms of milk production, the dry period (DP) is a non-productive time. In addition, the risk of mastitis increases when cows with daily milk yield >12.5kg are dried off, which is often the case when the DP is set to 55-60 days. References on the positive effects of a shortened DP on the metabolic health at the start of lactation and the subsequent reproductive performance were the motive of this review. Completely foregoing or shortening the DP produces a decrease in milk yield during the following lactation. This decrease is particularly pronounced for cows at the beginning of the second lactation. It is thought that this may be due in part to different involution and proliferation processes of the mammary glands in primiparous and multiparous animals. The majority of the scientific papers suggest that shortening the DP has a positive rather than a negative effect on udder health. The quality of the colostrum is also unaffected; but if there is no drying off, the colostrum will be diluted. When considered overall, the literature, with support from metabolic profile studies, appears to favour a reduced impact on energy metabolism in early lactation in circumstances when the DP is shortened or waived. Clear positive effects on parameters relevant to energy metabolism however only apply to multiparous animals, and other factors, such as milking frequency before and after calving, exert an influence. Positive effects of shortening the DP on the reproductive performance were shown in several studies. Time from calving to first ovulation as well as indicators for assessing the success of artificial insemination and reproductive performance showed better results in animals with no or shortened drying off periods. Again, this only applied to multiparous animals. Overall, there is no single clear answer to the question of an optimal length of the DP, but conversely it is abundantly clear that a dry period of 55-60 days is not necessary in all cases and does not make sense under certain circumstances. Based on the study findings from recent years, the determination of dry periods should be used as a farm-specific and needs-oriented applied management decision.

[Relationships between different parameters for the evaluation of the energy balance and the differential cell count in milk from cows with healthy udders]. / Zusammenhänge zwischen verschiedenen Parametern zur Beurteilung der Energiebilanz und Zellsubpopulationen in der Milch eutergesunder Kühe.

OBJECTIVE: The aim of the study was to investigate possible associations between the energy balance of dairy cows and the differential cell count in milk. Such associations could be used for the assessment of the mastitis risk due to metabolic stress. MATERIAL AND METHODS: In 15 red Holstein cows, samples were collected in the 2nd, 6th and 12th week post partum. To reflect the energy balance of the cows, the following parameters were evaluated: ß-hydroxybutyric acid (BHB) in serum, fat-protein-ratio (FEQ) in milk at times of examination and difference of the body condition score (DBCS) between times of examination. The overall somatic cell count (SCC) and the differential cell count were determined. Measuring the differential cell count, comprising fractions of lymphocytes (LYM), macrophages (MAK), polymorphonuclear leucocytes (PMN) and epithelial cells (EPI), was carried out using indirect immune fluorescent staining in combination with propidium iodide staining. The interrelationships between parameters of energy status and milk cells were statistically assessed using correlation analysis. Data which were not normally distributed were transformed using logarithms (log). A mixed model was used to test the associations between milk cell parameters and the parameters of energy balance, using the animal as a random effect. RESULTS: There was a significant correlation between FEQ and SCClog as well as between DBCS and SCClog (FEQ: r=0.459, p<0.01; DBCS: r=-0.301, p<0.05). Similarly directed correlations were found between both parameters of energy balance and LYMlog (FEQ: r=0.530, p<0.01; DBCS: r=-0.318, p<0.05) and MAKlog (FEQ: r=0.520, p<0.01; DBCS: r=-0.299, p<0.05). Univariate analysis provided the highest correlations between LYMlog and FEQ and between MAKlog and FEQ (LYMlog: F=17.36, p<0.01; MAKlog: F=14.46, p<0.01). CONCLUSION: The results of the study indicate associations between energy balance and the differential cell count in milk.

First outbreak of VIM-2 metallo-ß-lactamase-producing Pseudomonas aeruginosa in The Netherlands: microbiology, epidemiology and clinical outcomes.

This study was designed to investigate the prevalence and characteristics of metallo-ß-lactamase (MBL)-producing Pseudomonas aeruginosa in a tertiary care centre in The Netherlands, a country that is considered to have a low prevalence of antibiotic-resistant bacteria. Imipenem-resistant P. aeruginosa isolates cultured from clinical specimens during 2008-2009 were analysed phenotypically and molecularly by polymerase chain reaction (PCR) with sequencing. Genotyping was performed by multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA). Clinical information was obtained by electronic chart review for all patients infected or colonised with an imipenem-resistant P. aeruginosa isolate that was included in the study. In total, 106 imipenem-resistant P. aeruginosa isolates were included. The bla(VIM-2) gene was detected in 35/106 isolates (33%) and was associated with integrons. Compared with non-MBL-producing imipenem-resistant P. aeruginosa, VIM-2 MBL-producing isolates showed higher rates of multidrug resistance. Patients with VIM-2 MBL-producing isolates were more likely to be admitted to the Intensive Care Unit (ICU) and had a higher risk of invasive infection, including development of bacteraemia. MLVA identified two separate VIM-2 MBL-producing clones, responsible for outbreaks in the ICU but also affecting 10 other departments. This is the first reported outbreak of VIM-2 MBL-producing P. aeruginosa in The Netherlands. Once introduced, VIM-2 MBL-producing P. aeruginosa cause significant infections and are easily spread within the hospital setting.

Clinical impact of a highly prevalent Pseudomonas aeruginosa clone in Dutch cystic fibrosis patients.

Studies suggest that infection with highly prevalent Pseudomonas aeruginosa clones in cystic fibrosis (CF) is associated with an unfavourable clinical outcome. We studied the clinical characteristics of patients infected with a recently described, highly prevalent P. aeruginosa clone (ST406) in two CF centres in The Netherlands. Multilocus sequence typing data were available for 219 patients, of whom 40 (18.3%) were infected with ST406 and 179 with other sequence types. ST406 infection was independently associated with age, having a sibling with ST406 infection and use of inhaled antibiotics, but not with unfavourable clinical outcome, suggesting that high transmissibility is not necessarily associated with high virulence.

Endometritis in cattle experimentally induced by Chlamydia psittaci.

On the day of estrus, eight virgin heifers received intrauterine inoculations of yolk sac propagated Chlamydia psittaci strain BovEnd 11/88 isolated from the uterus of a slaughter cow. All heifers developed purulent vaginal discharge which persisted for 3 to 7 weeks. Chlamydiae or chlamydial antigen were detected in vaginal and uterine discharges of infected animals by culture or Capture ELISA, while other bacterial pathogens were not found. In sera of the chlamydia-infected heifers marked increases in antibody titres against the chlamydial genus-specific LPS-antigen were found by ELISA and complement fixation test. Six heifers were artificially inseminated in 5 successive cycles beginning at the first estrus following intrauterine inoculation. In two of the infected heifers spontaneous healing of endometritis occurred after 5 estrus cycles. Only these animals conceived after the 5th breeding, whereas in the remaining four animals a chlamydia-associated chronic endometritis was recognized as the cause of infertility in the 19th and 26th week p.i. at slaughter. Two control heifers which remained clinically normal after intrauterine exposure to sterile yolk sac-suspensions conceived at the 1st and 2nd service, respectively.

Computer based instruction is effective to teach dairy reproductive management.

This paper describes a classroom experiment in a German College of Veterinary Medicine (Tieraerztliche Hochschule Hannover) using an instructional software package designed to increase dairy reproductive problem-solving skills. A pre-test/post-test experimental design demonstrated that learning occurred in an enjoyable environment when 21 4th year veterinary students used the program. Students' perception in respect to content, design, and usability criteria of the program were excellent to good.