Interference Between Staphylococcus Epidermidis (Se) and Staphylococcus Aureus (Sa) in the Bovine Udder (original) (raw)
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Intramammary infections with different non-aureus staphylococci in dairy cows
Journal of Dairy Science, 2018
Subclinical mastitis causes an increase in milk somatic cell count (SCC) and can lead to reduced milk production and early culling. In many countries, nonaureus staphylococci (NAS) is the most common bacterial finding in subclinical mastitis of dairy cows. New methodology makes it possible to identify NAS species, but knowledge about the epidemiology is limited. The objective of this project was to improve advisory services for mastitis control by investigating associations between NAS and SCC, milk production, and persistence of intramammary infections (IMI). Farmers who had sent milk samples to the Swedish National Veterinary Institute (Uppsala, Sweden) were asked to participate if NAS was identified in the samples. Participating farmers were asked to resample all udder quarters of the cow once within 1 mo. Regression models were used to investigate associations between NAS and cow factors, udder quarter California mastitis test and SCC, and persistence of IMI. Associations with cow composite milk yield and SCC were also investigated. In total, 671 cows from 201 herds were enrolled in the study, and 19 NAS species were identified, of which the 4 most common were Staphylococcus epidermidis, Staphylococcus simulans, Staphylococcus chromogenes, and Staphylococcus haemolyticus. Persistent IMI was more common in udder quarters with Staphylococcus hyicus and S. simulans and less common in those with Staphylococcus saprophyticus IMI. β-Lactamase production by the different NAS species varied from 0 to 100%. There was a significant association between NAS species and California mastitis test and SCC of udder quarters, and this varied depending on parity. The cow composite milk SCC at the test milking before the initial sample was taken differed significantly with NAS species, but not at the subsequent test milking. Milk yield-at the test milking before or after the initial sample-did not differ significantly for NAS species. There were no significant associations between milk yield or SCC and persistent NAS IMI. In conclusion, the NAS species affects SCC and persistent IMI differently but not milk yield.
Dairy Cows’ Udder Pathogens and Occurrence of Virulence Factors in Staphylococci
Animals
This study investigated 960 Slovak and Czech spotted cattle from four different conventional (non-organic) dairy herds located in Eastern Slovakia and Czechia during early lactation (14–100 days after calving). Dairy cows were examined clinically; milk from fore-stripping of each udder quarter was subjected to sensory examination and assessed by the California mastitis test (CMT), and laboratory analyses of bacterial pathogens in milk, including virulence factors, were conducted. Positive CMT scores (1–3) for one or more quarters were detected in 271 (28.2%) of the examined animals. Out of 230 infected milk samples, representing 24.0% of all dairy cows, staphylococci (59.1% of positive findings) were the most commonly isolated organisms, followed by E. coli (11.3%), streptococci Str. uberis (9.1%) and Str. agalactiae (3.4%), and enterococci (6.1%). From 136 isolates of S. aureus (38 isolates) and non-aureus staphylococci (NAS; 98 isolates), virulence factors and their resistance to ...
Journal of Dairy Science
The aim of this study was to determine risk factors for bovine intramammary infection (IMI) associated with the most common bacterial species in Finland. Large databases of the Finnish milk-recording system and results of microbiological analyses of mastitic milk samples from Valio Ltd. (Helsinki, Finland) were analyzed. The study group comprised 29,969 cows with IMI from 4,173 dairy herds. A cow with a quarter milk sample in which DNA of target species was detected in the PathoProof Mastitis PCR Assay (Thermo Fisher Scientific, Waltham, MA) was determined to have IMI. Only cows with IMI caused by the 6 most common pathogens or groups of pathogens, coagulase-negative staphylococci (CNS), Staphylococcus aureus, Streptococcus uberis, Streptococcus dysgalactiae, Corynebacterium bovis, and Escherichia coli, were included. The control group comprised 160,176 IMI-free cows from the same herds as the study group. A multilevel logistic regression model was used to study herd-and cow-specific risk factors for incidence of IMI. Pathogen-specific results confirmed those of earlier studies, specifically that increasing parity increases prevalence of IMI regardless of causative pathogen. Holsteins were more susceptible to IMI than Nordic Reds except when the causative pathogen was CNS. Occurrence of IMI caused by C. bovis was not related to milk yield, in contrast to IMI caused by all other pathogens investigated. Organic milk production was associated with IMI only when the causative pathogen of IMI was Staph. aureus; Staph. aureus IMI was more likely to occur in conventional than in organic production. Cows in older freestall barns with parlor milking had an increased probability of contracting an IMI compared with cows in tiestall barns or in new freestall barns with automatic milking. This was the case for all IMI, except those caused by CNS, the prevalence of which was not associated with the milking system, and IMI caused by Staph. aureus, which was most common in cows housed in tiestall barns. A better breeding index for milk somatic cell count was associated with decreased occurrence of IMI, indicating that breeding for improved udder health has been successful in reducing the incidence of IMI caused by the most common pathogens in Finland. In the Finnish dairy sector, the importance of other measures to control IMI will increase as the Holstein breed progressively takes the place of the Nordic Red breed. Attention should be paid to hygiene and cleanliness, especially in old freestall barns. Based on our results, the increasing prevalence of automatic milking is not a reason for special concern.
Udder pathogens and their resistance to antimicrobial agents in dairy cows in Estonia
Acta Veterinaria Scandinavica, 2011
Background: The goal of this study was to estimate the distribution of udder pathogens and their antibiotic resistance in Estonia during the years 2007-2009. Methods: The bacteriological findings reported in this study originate from quarter milk samples collected from cows on Estonian dairy farms that had clinical or subclinical mastitis. The samples were submitted by local veterinarians to the Estonian Veterinary and Food Laboratory during 2007-2009. Milk samples were examined by conventional bacteriology. In vitro antimicrobial susceptibility testing was performed with the disc diffusion test. Logistic regression with a random herd effect to control for clustering was used for statistical analysis. Results: During the study period, 3058 clinical mastitis samples from 190 farms and 5146 subclinical mastitis samples from 274 farms were investigated. Positive results were found in 57% of the samples (4680 out of 8204), and the proportion did not differ according to year (p > 0.05). The proportion of bacteriologically negative samples was 22.3% and that of mixed growth was 20.6%. Streptococcus uberis (Str. uberis) was the bacterium isolated most frequently (18.4%) from cases of clinical mastitis, followed by Escherichia coli (E. coli) (15.9%) and Streptococcus agalactiae (Str. agalactiae) (11.9%). The bacteria that caused subclinical mastitis were mainly Staphylococcus aureus (S. aureus) (20%) and coagulase-negative staphylococci (CNS) (15.4%). The probability of isolating S. aureus from milk samples was significantly higher on farms that had fewer than 30 cows, when compared with farms that had more than 100 cows (p < 0.005). A significantly higher risk of Str. agalactiae infection was found on farms with more than 600 cows (p = 0.034) compared with smaller farms. The proportion of S. aureus and CNS isolates that were resistant to penicillin was 61.4% and 38.5%, respectively. Among the E. coli isolates, ampicillin, streptomycin and tetracycline resistance were observed in 24.3%, 15.6% and 13.5%, respectively. Conclusions: This study showed that the main pathogens associated with clinical mastitis were Str. uberis and E. coli. Subclinical mastitis was caused mainly by S. aureus and CNS. The number of S. aureus and Str. agalactiae isolates depended on herd size. Antimicrobial resistance was highly prevalent, especially penicillin resistance in S. aureus and CNS.
Virulence Factors and Prevalence of Udder´s Pathogens in Dairy Cows during the Peripartal Period
Asian Journal of Agriculture and Food Sciences
Data presented in this study described the prevalence of udder pathogens and presence of virulence factors in staphylococci isolated from mastitis in dairy cows. The practical part of study was realized in five different dairy herds of Slovak spotted cattle breed located in Eastern Slovakia with conventional (non-organic) farming. At the beginning of lactation (during first two months after calving) were comprehensively investigated 960 cows from monitored herds. The comprehensive examination included clinical examination, sensory analysis of milk from fore stripping of each udder quarter, followed by assessment of the California mastitis test (CMT) and laboratory analyses of bacteria pathogens. Screening the health status of the mammary gland revealed that 314 cows (32.7%) had positive CMT score (1-3) for one or more quarters. Out of 230 infected milk samples, representing 24.0% of all dairy cows examined, were the most commonly isolated staphylococci (59.1% of positive findings), ...
Bovine Mastitis-Diagnosis, Bacteriological Status of Milk and Antimicrobial Resistance of Pathogens
Quarter milk samples (n=200) from 50 dairy cows (Holstein breed) in Hohenheim region, Stuttgart, Germany, were examined to study the occurrence and causes of mastitis, distribution of mastitis pathogens and in vitro antimicrobial susceptibility of different mastitis pathogens. The study revealed that 75 (37.5 %) quarters had positive California mastitis test (CMT). 45 (60.0 %) of them had CMT score 3, while 25 (33.3 %) showed CMT score 2 and 5 (6.7 %) gave score 1. All positive quarters 75 (37.5 %) had significantly higher mean value of somatic cell counts (437.3 x10 3 cells/mL). So, all these quarters were considered positive for mastitis (>200.000 cells/mL). Bacteriological examination of these positive quarters (75) revealed that 63 (84.0 %) quarters yielded bacteria and 12 (16.0 %) not grow. Staphylococcus aureus, Staph. epidermidis, Streptococcus uberis, Strept. agalactiae, Corynebacterium bovis and E. coli were the main organisms. These strains were isolated at varying percentages 14.2, 19.2, 26.6, 10.0, 17.5 and 12.5 %, respectively. The average somatic cell counts calculated from quarter milk samples in relation to isolated bacterial strains were, 391.4, 416.9, 476.4, 740, 357.3 and 542 x10 3 cells/mL, respectively. According to in vitro antimicrobial susceptibility testing, the Staphylococcus aureus demonstrated the highest level of resistance (100.0 %) to Penicillin, lincomycin, Colistin,Triple sulfa, Bacitracin, Chloramphenicol and Clindomycin. While, Staph. epidermidis (coagulase negative Staphylococci) gave the same resistance level against Triple sulfa, Bacitracin and Clindomycin. However, in case of Colistin and Polymyxin B it was decreased to 95.7 %. All isolated strains of Streptococcus uberis (32) gave resistance to Triple sulfa, Bacitracin, Chloramphenicol and Clindomycin by a percentage of 100.0 %. This percent was varying with other antibiotics where it became 96.9 % with Colistin and Sulfamethoxazol and 87.5 % against Neomycin and Trimethoprim. Streptococcus agalactiae isolated strains (12) were very susceptible to Erythromycin, Penicillin, Lincomycin, Amoxicillin, Ampicillin, Tetracycline, Oxacillin, Cefoperazon, Sulfamethoxazol and Cefalexin treatment. Corynebacterium bovis showed complete resistance (100.0 %) with antibiotic discs of Trimethoprim, Triple sulfa, Bacitracin, Sulfamethoxazol, Chloramphenicol and Clindomycin. E. coli revealed 100.0 % resistance to Gentamycin and Triple sulfa and 80.0 % to Amoxicillin, Polymyxin B, Colistin, Neomycin, Trimethoprim, Sulfamethoxazol and Cefalexin. The economic importance and public health significance of existing microorganisms as well as the suggested measures for improving the keeping quality as well as the sanitary condition of raw milk and its products were discussed.
Acta Veterinaria Scandinavica, 2011
Background: A nationwide survey on the microbial etiology of cases of subclinical mastitis in dairy cows was carried out on dairy farms in Sweden. The aim was to investigate the microbial panorama and the occurrence of antimicrobial resistance. Moreover, differences between newly infected cows and chronically infected cows were investigated. Methods: In total, 583 quarter milk samples were collected from 583 dairy cows at 226 dairy farms from February 2008 to February 2009. The quarter milk samples were bacteriological investigated and scored using the California Mastitis Test. Staphylococci were tested for betalactamase production and presence of resistance was evaluated in all specific udder pathogens. Differences between newly infected cows and chronically infected cows were statistically investigated using logistic regression analysis. Results: The most common isolates of 590 bacteriological diagnoses were Staphylococcus (S) aureus (19%) and coagulase-negative staphylococci (CNS; 16%) followed by Streptococcus (Str) dysgalactiae (9%), Str. uberis (8%), Escherichia (E.) coli (2.9%), and Streptococcus spp. (1.9%). Samples with no growth or contamination constituted 22% and 18% of the diagnoses, respectively. The distribution of the most commonly isolated bacteria considering only bacteriological positive samples were: S. aureus-31%, CNS-27%, Str. dysgalactiae-15%, Str. uberis-14%, E. coli-4.8%, and Streptococcus spp.-3.1%. There was an increased risk of finding S. aureus, Str. uberis or Str. dysgalactiae in milk samples from chronically infected cows compared to findings in milk samples from newly infected cows. Four percent of the S. aureus isolates and 35% of the CNS isolates were resistant to penicillin G. Overall, resistance to other antimicrobials than penicillin G was uncommon. Conclusions: Staphylococcus aureus and CNS were the most frequently isolated pathogens and resistance to antimicrobials was rare.
Udder Health and Communication, 2011
The objective of this study was to unravel the innate immunological response after administration of a novel vaccine (Startvac®, HIPRA, S.A., Amer, Spain), containing the inactivated Escherichia coli J5 strain and the Staphylococcus aureus SP 140 strain expressing Slime Associated Antigenic Complex (SAAC). In a challenge trial, the effect of vaccination on milk neutrophil viability and concentration as well as on the antigen-specific antibodies anti-SAAC and anti-J5 was determined and several clinical parameters were observed. Eight animals were included of which four were immunized at 45 days before the expected calving date followed by a second vaccination 35 days later. The other four cows serve as non-vaccinated controls. Fifteen days after calving, two contralateral quarters of each cow were inoculated with an inactive S. aureus isolate. Phosphate buffered saline was administered to the two control quarters. Blood samples are collected at 45 and 10 days before calving as well as at 15 days after calving just before the infection is induced. Quarter of each cow were inoculated with an inactive S. aureus isolate. Phosphate buffered saline was administered to the two control quarters. Blood samples are collected at 45 and 10 days before calving as well as at 15 days after calving just before the infection is induced. Quarter milk samples are collected at 2 hours before, and at 4, 12, 24 and 48 hours after challenge. During the entire trial bacteriological culture and somatic cell count of the milk of all four quarters was frequently evaluated, this to exclude interference with naturally occurring intramammary infections. In conclusion, vaccinated cows seem to develop a less severe inflammatory reaction after inoculation compared to non-vaccinated animals. Vaccination also increased the level of the antigenspecific antibodies anti-SAAC and anti-J5 in blood which might eventually result in a shorter duration of the infection. However, further research is definitely needed before final conclusions on the impact of prepartum vaccination on the cows' innate immune response and their udder health status shortly after calving can be drawn.
Veterinary microbiology, 2009
Dairy heifers represent the future of a dairy herd, and are expected to freshen with a healthy and well-developed udder, capable of producing an optimal amount of high quality milk. A high proportion of heifers have infected mammary quarters at calving, with coagulase-negative staphylococci (CNS) being the most common cause. Staphylococcus aureus and environmental pathogens are also found. The aim of this paper is to summarize how intramammary infections during (late) gestation and early lactation impair the development of the mammary gland and negatively affect future udder health and milk production. Heifers calving with either subclinical or clinical mastitis are also at a higher risk to be culled in first lactation. The magnitude of the effect is most likely related to the virulence of the causative pathogen, the persistence of the infection when milk production has started, and the time of onset of infection. Histological changes in udder tissue from quarters infected with S. a...
Milk Leucocyte Population Patterns in Bovine Udder Infection of Different Aetiology
Journal of Veterinary Medicine Series B, 2000
This study compared the different leucocyte populations in milk from udders infected with different mastitic pathogens and in different stages of infection. Milk samples were collected from quarters free of intramammary infection, acutely infected with Escherichia coli or Staphylococcus aureus and chronically infected with S. aureus, coagulase-negative staphylococci (CNS) or Streptococcus dysgalactiae. Udder bacteriological status was confirmed after three consecutive bacteriological examinations from weekly quarter milk samples. At the time of the trial, milk samples were tested for somatic cell count (SCC) and differential cell count by both light microscopy (LM) and flow cytometry. Monoclonal antibody (mAb) CD11a/CD18 was used in order to differentiate between leucocytes and epithelial cells when tested by flow cytometry. Udder quarters free of intramammary infection had a mean SCC lower than 107 × 10 3 cells/ml in which the epithelial cells were the main cell type followed by polymorphonuclear cells (PMNs), while macrophages and lymphocytes had a lower concentration. Only 56 % of the cells were labelled with the mAb anti-CD11a/CD18. In either acute E. coli-or S. aureus-infected quarters, SCC were significantly higher (P ³ 0.0001) than in samples from the time of inoculation, with over 90 % of the cells labelled with the mAb anti-CD11a/CD18. The main cell type was neutrophils. In chronically infected cows, differences in SCC and in leucocyte patterns were found between infecting pathogens as well as between quarters harbouring the same pathogen. In all the chronically infected quarters, SCC was significantly higher (P ³ 0.05) than in uninfected ones. The distribution of the leucocyte patterns in the quarters infected with S. dysgalactiae did not differ from that in quarters with acute infection with both E. coli and S. aureus. In the cows chronically infected with S. aureus or CNS, the proportion of PMN was higher but not significantly different from quarters free of intramammary infection, while epithelial cells were significantly lower (P ³ 0.05). The T lymphocytes bearing CD4 + or CD8 + were significantly higher in quarters chronically infected with S. aureus than in quarters free of intramammary infection and in quarters acutely infected with either E. coli or S. aureus. In all samples B cells were negligible.