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The aim of the present study was to assess the haemolytic and proteolytic activity of coagulase- negative staphylococci (CNS) isolated from cows with mastitis. The study was conducted on 100 CNS strains: S. xylosus (n=28), S.chromogenes (n=26), S.haemolyticus (n=25), S. sciuri (n=14), S. warneri (n=4), S.hominis (n=2), S.saprophyticus (n=1); 22 CNS were isolated from cows with clinical mastitis and 78 from those with subclinical mastitis. The CNS studied showed the ability to produce only α-haemolysin and belonged to one strain – S. haemolyticus (21.0% of isolated CNS strains). Haemolysin-positive CNS were responsible for both clinical and subclinical mastitis (22.7% and 20.5%, respectively). The ability to produce protease was found in 31.0% of CNS belonging to two strains: S. chromogenes and S. sciuri. Protease-positive CNS were the etiological factor of both clinical and subclinical mastitis (31.8% and 30.8%, respectively). All S. xylosus, S. warneri, S. hominis, and S. saprophyticus strains were found protease-negative and haemolysin-negative, irrespective of whether they caused clinical or subclinical mastitis in cows.
The aim of the present study was to evaluate the antibiotic susceptibility of methicillin-susceptible (MS) and methicillin-resistant (MR) coagulase-negative Staphylococcus (CNS) strains isolated from milk of cows with mastitis. The study was conducted on 100 CNS strains (20 MRCNS and 80 MSCNS) isolated from milk samples of 86 cows from the Lublin (Poland) region farms. Antibiotic susceptibility of microorganisms was evaluated using the disc-diffusion method on the Mueller-Hinton agar according to the guidelines of the National Committee for Clinical Laboratory Standards (NCCLS). The highest efficacy against MSCNS was demonstrated for cephalosporin antibiotics, i.e. cefacetril (91.3%), ceftiofur (67.5%), cefoperazone (66.3%) and cephalexin (60.0% of susceptible MSCNS strains). Moreover, a high percentage of vancomycin-susceptible strains was demonstrated (83. 8%). The activity of combination of amoxicillin with clavulanic acid and gentamicin was found weaker (63.8% and 61.3% of susceptible strains, respectively). About 50.0% of MSCNS were susceptible to erythromycin, enrofloxacine and amoxicillin. A large proportion of CNS was resistant to neomycin, penicillin, tetracycline, streptomycin, lincomycin and ampicillin (28.8%, 30.0%, 31.3%, 31.3%, 33.8% and 33.8% of susceptible strains, respectively). The highest percentage of MRCNS was susceptible to vancomycin (75.0%), erythromycin (65.0%) and streptomycin (50.0%). Their susceptibility to enrofloxacine (35.0%) as well as gentamicin and tetracycline (30.0%) was markedly lower. The lowest activity was found for lincomycin and neomycin (20.0% of susceptible MRCNS strains, each).
The aim of the present study was to determine the concentration of C-reactive protein (CRP) and serum amyloid A (SAA) in bitches suffering from spontaneously occurring mammary gland tumors. The experiment involved 30 bitches with malignant gland tumors removed surgically (carcinoma complex - 40%, carcinoma simple - 26.7%, sarcoma - 23.3%, carcinosarcoma - 10%) and 10 clinically healthy bitches. Measurements of the CRP and SAA serum concentration were performed using a commercial ELISA test. The concentration of CRP as well as SAA were significantly higher in bitches with sarcomas or carcinosarcomas compared with the animals with carcinomas (complex or simple) and the control group. Histopathological examination showed extensive areas of necrosis and inflammatory reactions in most sarcomas and carcinosarcomas. Most likely these were the main causes of the CRP and SAA increase in the serum of bitches with these type of tumors.
The aim of study was to assess the incidence of mycotic mastitis in the middle-eastern part of Poland, and to determine genera and species of yeasts, which cause this kind of inflammation. The study involved 2,122 milk samples from cows with clinical and subclinical mastitis from the Lublin and Warsaw regions. The aseptic samples of milk or infected secretions were cultured on the agar and Sabouraud medium with addition of chloramphenicol. Fungi constituted 7.07% of all aetiological agents of mastitis. Four species of fungi were isolated: Candida, Trichosporon, Rhodotorida, and Cryptococcus. Candida sp. was most commonly isolated. The most abundant species included C. krusei, C. kefyr, and C. lusitaniae. Yeast-like fungi were most frequently isolated at the end of winter and in spring.
The aim of the study was to evaluate enzymatic activities of yeasts isolated from inflammatory mammary secretion. The yeasts isolated from cows with clinical and sub-clinical mastitis (134 strains) included: Candida krusei (62 strains), Candida kefyr (48 strains), Candida lusitaniae (17 strains) and Candida famata (7 strains). The API ZYM system was used containing substrates to assess 19 hydrolytic enzymes. Substantial differences in the number and activity of hydrolyses were demonstrated in individual species. In Candida krusei, acid phosphatase showed the highest activity (4.36 points), in Candida kefyr and Candida lusitaniae – leucine arylamidase (4.93 and 4.25 points, respectively), in Candida famata – α-glucosidase (4.75 points). No activity of trypsin, chymotrypsin, α-galactosidase, β-glucuronidase, α-mannosidase or α-fucosidase was observed in any of the yeasts examined.
The aim of this study was to determine the mechanisms of staphylococcal resistance to methicillin. CNS (n=100 isolates) were prepared from the mammary inflammatory secretions of 86 cows from farms located in the Lublin region. Methicillin-resistant isolates constituted 20.0% of all CNS. Staphylococcus sciuri (n=8) and Staphylococcus xylosus (n=6) were most abundant, followed by Staphylococcus chromogenes (n=3), Staphylococcus haemolyticus (n=2) and Staphylococcus warneri (n=1). The mecA gene was found in 50.0% of MRCNS (10.0% of all CNS isolates) belonging to two species: S. sciuri and S. xylosus. All mecA-positive isolates contained the protein of low affinity to penicillin (penicillin-binding protein 2a – PBP2a). The enzyme hydrolysing the β-lactam ring in antibiotics was detected in 40.0% of MRCNS; 10.0% of MRCNS isolates were characterised by the presence of the mecA gene and ability to produce β-lactamase. The remaining 20.0% of MRCNS isolates showing phenotypic resistance to methicillin were mecA gene-negative and were not able to produce β-lactamase.
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