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Objective: The relationship between the in vitro detected virulence factors biofilm and capsule formation of Streptococcus (S.) uberis isolates of clinical mastitis in dairy cows and the bacteriological cure rate after antibiotic therapy was investigated in order to better understand the importance of these virulence factors for the bacteriological cure rate., Material and Methods: A total of 111 clinical mastitis (CM) cases were collected, in which S. uberis was bacteriologically detected. All mastitis cases were treated in accordance with the approval conditions of the antibiotic udder tubes used. Individual cow information including age, number of lactations, current lactation mastitis and antimicrobial treatment received was recorded. The microtiter plate test was used to detect biofilm formation and Anthony capsule staining was used to detect capsular capacity. Statistical analyses were performed to characterize the correlation between in vitro virulence factors and bacteriological cure (BC) rate., Results: 30.5% (n=29) of the S. uberis isolates of bacteriologically cured cases and 34.5% (n=10) of the isolates of bacteriologically non-cured mastitis cases were found to have the ability to produce capsules in vitro . 70.7% (n=58) of the S. uberis isolates from bacteriologically cured mastitis cases had the ability to produce biofilm in vitro , whereas 58.6% (n=17) of the isolates of non-cured mastitis cases showed ability in producing biofilm. No correlation was found between the in vitro ability of S. uberis to form capsules and biofilms and the BC rate after antibiotic treatment of bovine mastitis., Conclusion(s): The present work has shown that the investigated in vitro virulence factors are not associated with the BC after antibiotic therapy. Further studies on the role of S. uberis virulence factors are needed to complete the missing knowledge on the difficulties in curing S. uberis mastitis., Clinical Relevance: This study is of great clinical relevance since it enhances the understanding of the occurrence of BC in S. uberis mastitis cases. The investigated virulence factors are often addressed as possible reasons for therapy failure, although respective scientific studies are missing., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Objective: To evaluate the relative efficacy of a novel, commercially available disinfecting agent containing ≥ 15 to < 20 % glutaraldehyde in a hydro-colloid matrix ("EIMÜ Klauen Sprint ® "; Eimermacher, Nordwalde, Germany, Biozid-Desinfektionsmittel, BAuA Nr. N-57213) as a walkthrough footbath in order to treat digital dermatitis of dairy cattle., Material and Methods: The study was conducted in a dairy farm located in northern Germany from June 1st, 2015 to September 5th, 2015. Eighty-eight cows were enrolled in this study. In both trials of the study, a walkthrough footbath was applied on five consecutive milking times per week. Trial 1 was a blinded, randomised and controlled intervention study. The therapy group (n = 40) received the novel glutaraldehyde product in a 2 % solution while the control group (n = 40) was led through a footbath containing pure water. Trial 2 was a longitudinal study to investigate the development of claw health over a longer time period regarding the use of the new footbath solution. In trial 2 the disinfecting footbath was applied to all trial cows (therapy and control group) of trial 1. The development of claw health and lameness was systematically monitored in the two groups on days 0, 9, 17, 29, 35 (trial 1) and days 42, 68, 94 (trial 2), respectively. The adjusted odds of digital dermatitis lesions (DDL) throughout the study were analysed by mixed logistic regression models., Results: The odds of DDL were 0.15 for the glutaraldehyde foot-bath group compared to the control group. Hence, the disinfecting footbath significantly reduced the DDL prevalence and increased the cure rate of DDL. However, no preventive effect on new digital dermatitis (DD) cases could be identified., Conclusion: The efficacy of the novel glutaraldehyde footbath was evaluated and it was concluded that "EIMÜ Klauen Sprint ® " was well tolerated over a longer period of time and might therefore be an effective tool to control DD., Clinical Relevance: In future, "EIMÜ Klauen Sprint ® " could be used within a Mortellaro sanitation concept and thereby might help to solve a major problem of dairy cattle farms., Competing Interests: The authors confirm that they do not have any conflict of interest., (Georg Thieme Verlag KG Stuttgart · New York.)

The aim of this study was to review factors affecting the probability of cure of bovine mastitis and thereby establish criteria for deciding whether to treat or cull individual animals. A further objective was to avoid redundant treatment with antibiotics so as to reduce the risk of pathogen resistance and enhance economic benefit. In evaluating success of therapy, bacteriological cure is the standard type of cure and is defined as elimination of mastitis-causing pathogens from the mammary gland. Administration of antibiotics is considered reasonable only when there is a prospect of bacteriological cure. In addition to age of the affected cow, the history of mastitis, number of infected quarters and somatic cell count affect the probability of bacteriological cure. Identifying and characterising chronic mastitis, which causes enormous production losses, are especially important to prevent unnecessary treatment and to decide whether or not to cull. To our knowledge, this is the first work providing a complete list of factors that have been confirmed in scientific literature to influence the probability of cure. This review should support farmers and veterinarians in deciding between culling and administering appropriate therapy to an affected animal.

Mastitis is one of the most common and expensive diseases in dairy cattle. The decision to treat clinical mastitis is usually made without any knowledge of the etiology, and can therefore only be evidence-based to a limited extent. Evidence-based medicine relies essentially on a combination of one's own clinical competence and scientific findings. In mastitis therapy, those insights depend mostly on pathogen-specific factors. Therefore, in evidence-based therapeutic decision making the pathogen identification should serve as a basis for the consideration of scientifically validated therapeutic concepts. The present paper considers evidence-based treatment of clinical mastitis based on a literature review. The authors conclude that an anti-inflammatory treatment using an NSAID should be conducted regardless of the pathogen. However, the choice of an antibiotic therapy depends on the mastitis causative pathogen, clinical symptoms and the animal itself. In principle, a local antibiotic treatment should be chosen for mild and moderate mastitis. It should be noted, that the benefit of an antibiotic therapy for coliform infections is questionable. With knowledge concerning the pathogen, it appears entirely reasonable to refrain from an antibiotic therapy. For severe (i.   e. feverish) mastitis, a parenteral antibiotic therapy should be selected. An extension of the antibiotic therapy beyond the manufacturer's information is only reasonable for streptococcal infections. It is important to make the decision on a prolonged antibiotic therapy only with the knowledge of the mastitis-causative pathogen. In terms of the therapy of a staphylococcus or streptococcus infection, a narrow-spectrum antibiotic from the penicillin family should be adopted when selecting the active agents.

Clinical mastitis as a frequently recurrent event can cause substantive economic loss on dairy farms. The reason for recurrent mastitis can be either a persistent infection of the bovine mammary gland by a mastitis pathogen or a reinfection of a quarter or udder after bacteriological cure. The virulence properties of a mastitis pathogen and the cure odds of an individual cow determine the development of persistent infections. Clinical episodes may alternate with periods without symptoms in the course of persistent infections. Strategies to reduce cases of recurrent mastitis have to include improved treatment concepts and measures to decrease new infection rates. The present literature review summarises the knowledge of definitions, frequencies, causes and effects of recurrent mastitis.

The dry period poses an extraordinarily high risk of new infections for the bovine mammary gland. Environmental pathogens are of particular importance during this time. Normally, an infection during the dry period does not cause clinical symptoms, but is often responsible for clinical mastitis in the first weeks of lactation. Reducing new infections in dry cows can significantly decrease mastitis incidence in early lactation. During the course of the dry period, the new infection rate does not remain constant, but peaks immediately after drying off and shortly before calving. The chance of a new infection is influenced multifactorially by the animal, pathogen and environment. In this context, the closure of the teat canal using a keratin plug is very important. There are different approaches to antibiotic dry cow treatment. Either all udder quarters of all dry cows are treated (blanket dry-cow treatment) or just the udder of animals with a proven infection or an increased somatic cell count (selective dry-cow treatment). In the latter case, all udder quarters of an animal may be treated or just the one in which the infection or the increased somatic cell count was found. Instead of, or as a supplement to antibiotic treatment, teat sealers can be used. They support or take over the function of the keratin plug by closing the teat canal. In addition, there are some alternative methods to prevent new infections. Nevertheless, reducing the risk of infection is of primary importance. For this purpose, there are numerous options for improving hygiene in the environment of dry cows.

Mastitis in cattle is an infection of the mammary gland caused by infection, toxins and/or trauma. Currently, it is assumed that there is a correlation between higher amounts of residual milk and the incidence of clinical mastitis. The amount of residual milk can be examined using different methods. Higher amounts of residual milk may result from an insufficient teat condition and individual detachment settings of milking units. To date, scientific literature has already discussed the relationship between high amounts of residual milk, undermilking and the occurrence of clinical mastitis. The present paper reviews the current status of knowledge regarding residual milk and risk of mastitis.

Objective: For the early detection of udder health disorders in praxi, it is necessary to use a method with high sensitivity. The aim of the present study was to investigate the sensitivity of a commercial Califor- nia Mastitis Test and a new reagent which was optimised for the detection of udder health disorders with somatic cell counts > 100,000 cells/ml., Material and Methods: The viscosity of mixtures of test milks with standardised somatic cell counts (50,000-800,000 cells/ml) and test reagents were analysed in vitro. A total of 50 quarter fore- milk samples from cows without signs of clinical mastitis were investigated using both California Mastitis Test reagents. Sensitivity and specificity were calculated., Results: The viscosity of mixtures increased with a higher somatic cell count. At a somatic cell count of 50,000 cells/ml, the mean viscosities were 3.20 mPa*s (commer- cial product) and 2.69 mPa*s (optimised reagent). At a somatic cell count of 100,000 cells/ml the viscosities increased to 3.43 mPa*s and 4.58 mPa*s, respectively. At a somatic cell count threshold of 100,000 cells/ml, marking the transition of the physiological status into a secretion disorder, the sensitivity of the commercial test was 76.7% and that of the optimised test was 97.7%., Conclusion and Clinical Relevance: The optimised California Mastitis Test allows - compared to the commercial product - the early detection of quarters or animals with high somatic cell counts. The results of the study indicate that the test result has to be evaluated immediately after the California Mastitis Test reaction.

Monitoring udder health of a dairy herd has three functions: firstly describing the actual situation, secondly evaluating the efficiency of adopted improvement measures and treatments, thirdly to detect emerging problems as early as possible. Therefore, husbandry, feeding, and management of the cows have to be included in the surveillance. Risk-based monitoring of the udder health is characterized on the one hand by focussing on the currently relevant herd-specific risk factors. Consequently, it is a dynamic process. On the other hand, it is affected by a clearly structured approach to prevent a loss of control due to a lack of attention in any area. All essential decisions and actions are documented to be comprehensible and available for critical examination. This review explains the procedure to establish a risk-based monitoring program on dairy farms.

Objective: Especially in cases of clinical mastitis a rapid test for identification of responsible pathogens would be useful for choosing the appropriate treatment. The objective of the study was to determine whether two rapid tests are suitable to detect infections with coliforms and Staphylococcus aureus, respectively, in cows with acute mastitis under field conditions., Material and Methods: The evaluated tests were "Petrifilm™ Rapid Coliform" and "Petrifilm™ Staph Express Count System". A total of n=107 double, quarter foremilk samples from dairy cows with clinical signs of acute mastitis was obtained aseptically. All samples were examined microbiologically by means of both conventional methods and using both Petrifilm™ tests., Results: Overall sensitivity for the Petrifilm™ tests was 32%, overall specificity 90%, and the positive predictive value 24%. In contrast, conventional methods yielded positive results in only 18% of cases, meaning that with the petrifilm kits, 3.5 times more infections caused by coliforms could be detected. However, not all coliforms cultivated conventionally were also identified by the Petrifilm™ tests., Conclusion and Clinical Relevance: These unsatisfactory results may be due to flaws in the conventional culturing or contamination of samples. Therefore, the results of this field trial do not lead to a conclusive evaluation of this diagnostic device under field conditions, although the Petrifilm™ test for coliforms may already be recommended to identify infections caused by gram-negative microorganisms. Once caution is taken at sampling, this kit may lead to a basic decision regarding therapy.

Objective: The teat canal of lactating dairy cattle is the first barrier against mastitis pathogens invading the teat cistern and the udder lumen. However, in several studies it could be shown that the teat skin and the teat canal epithelium are colonized by mainly staphylococci as well as by other pathogenic or facultative pathogenic micro-organisms. The aim of the study was to evaluate the pathogen pressure on the bovine mammary gland and to establish data on the prevalence of relevant micro-organisms., Material and Methods: In 32 randomly selected German dairy farms the colonization of the teat skin and the teat canal by S.aureus (Baird Parker agar), Sc.uberis (modified Rambach agar according to Watts et al. [1993]), enterococci (kanamycin esculin azide agar) and coliforms (ChromoCult Coliform agar) was investigated by the wet/dry swab technique DIN10113-1:1997-07., Results: In total 84.5% of all 1358 investigated teat canals of clinically healthy cattle were colonized by at least one of the four pathogen groups. S.aureus was isolated from 72.2% of the teat canals. For S.aureus , Sc.uberis and E.coli maximum bacterial counts of >10(6) cfu/swab and for other coliform bacteria>10(7) cfu/swab were detected. Correlations could be found between the bacterial counts on the teat skin and in the teat canal within the pathogen groups S.aureus, Sc.uberis, E.coli and other coliforms (Spearman's rank correlation coefficient r≥0.30, p<0.001) as well as between the environmental udder pathogens Sc.uberis and coliforms (r≥0.25, p<0.01)., Conclusion and Clinical Relevance: The variation of the bacterial counts on teat epithelia could be an indicator that the microflora of the teat canal epithelium can be affected by management practices in dairy farms. The results of this study point out that under field conditions the efficiency of hygienic practices (husbandry, milking) can be assessed by sampling of the bovine teat canal by the wet/dry swab technique.