Acute-phase inter-alpha-trypsin inhibitor heavy chain 4 levels in serum and milk of cows with subclinical mastitis caused by Streptococcus species and coagulase-negative Staphylococcus species

The aim of the study was to investigate the concentrations of acute-phase inter-a-trypsin inhibitor heavy chain 4 (ITIH4) in serum and milk of cows with subclinical mastitis caused by Streptococcus sp. (STR) and coagulase-negative Staphylococcus sp. (CNS) and healthy cows. The blood and milk samples were obtained from 60 mid-lactation, multiparous Holstein-Friesian cows from 7 herds in the Lublin region of Poland. In the milk samples from 40 cows with subclinical mastitis, Streptococcus sp. and CNS were isolated. The ITIH4 was significantly higher in serum of cows with subclinical mastitis caused both by STR and CNS compared with healthy cows. One hundred percent of animals infected with Streptococcus sp. and 89% of animals infected with Staphylococcus sp. showed ITIH4 concentration in sera higher than 0.5 mg/mL. The concentration of ITIH4 in milk also was significantly higher in cows with subclinical mastitis caused by Streptococcus sp. and Staphylococcus sp. compared with the control group. Seventy percent of cows infected by STR and CNS showed ITIH4 concentration in milk higher than 2.5 µg/mL. Milk ITIH4 concentration higher than 5 µg/mL was found in 55% of animals infected with Streptococcus sp. and in 40% of animals infected with Staphylococcus sp. No statistically significant differences were observed in ITIH4 concentrations both in serum and in milk between the studied unhealthy animal groups. These results suggest that ITIH4 may be used in the future as a novel diagnostic marker in serum and in milk of subclinical mastitis in cows

Bringing Agriculture into the GATT: Assessing the Benefits of Trade Liberalization

International Relations/Trade,

Antibiotic susceptibility of methicillin - resistant and methicillin - suspectible coagulase-negative staphylococci isolated from bovine mastitis

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)

Haemolytic and proteolytic activity of coagulase-negative staphylococci isolated from mastitis cows

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

Production of slime by coagulase-negative staphylococci (CNS) isolated from clinical and subclinical mastitis in cows

The aim of the study was to evaluate the slime-producing ability of coagulase-negative staphylococci (CNS) isolated from clinical and subclinical mastitis in cows. The study was carried out on 100 isolates of CNS obtained from milk of 86 cows from farms located in the Lublin region (Poland). Slime-producing ability was observed in over half of coagulase-negative staphylococci (54.0% of isolated CNS), including 19 isolates of methicillin-resistant staphylococci (95.5% of all MRCNS). Of 22 isolates of CNS responsible for the clinical form of mastitis, 20 isolates (90.9%) produced slime: S. xylosus (7 isolates), S. haemolyticus (6 isolates), S. chromogenes (4 isolates), and S. sciuri (3 isolates), including 9 isolates of MRCNS (45.0%). The remaining 34 isolates of CNS (43.6%) with the ability to produce this exopolysaccharide were isolated from the milk of cows with subclinical form of mastitis: S. xylosus (12 isolates), S. sciuri (9 isolates), S. chromogenes (6 isolates), S. haemolyticus (3 isolates), S. warneri (3 isolates) and S. saprophyticus (1 isolate), including 10 isolates of MRCNS (12.8%)

Enzymatic activity of yeasts isolated from the inflamed mammary secretion in dairy cows

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

Resistance to methicillin of coagulase-negative staphylococci (CNS) isolated from bovine mastitis

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

Coagulase-negative staphylococci (CNS) as an aetiological factor of mastitis in cows

The aim of the present study was to determine the proportions of individual coagulase-negative Staphylococcus species in clinical and subclinical mastitis. The material consisted of 100 CNS isolates obtained from 223 milk samples collected from cows with clinical and subclinical mastitis. Coagulase-negative staphylococci constituted 44.8% of all isolated microorganisms. CNS were isolated from the mammary gland secretions of 86 cows from farms in the Lublin region (Poland). Clinical mastitis was found in 20 whereas subclinical mastitis in 66 study cows (23.3% and 76.7%, respectively). The symptoms of clinical mastitis were mild. The clinical forms of mastitis concerned mainly the first or second lactation. Subclinical mastitis was most commonly observed during the second lactation. Four CNS species (S. xylosus, S. chromogenes, S. haemolyticus and S. sciuri ) were isolated from clinical and subclinical mastitis. S. xylosus was the commonest CNS species isolated from cows with clinical mastitis whereas S. chromogenes was the most prevalent one in subclinical mastitis cases. The three CNS species (S. warneri, S. hominis and S. saprophyticus) caused only subclinical mastitis