Oral and Poster Abstracts

and 5.86 % on quarter basis respectively. The hind quarters were more
frequently affected than the fore quarters
Bacteriological examination of milk samples revealed that staphylococci
were the chief etiological agents both in clinical and sub clinical mastitis
(41.67%) in camels, followed by Streptococcus spp. (21.67%),
Enterobacter spp. (15.00%), C. pyogenes (10.00%), Micrococcus spp.
(5.00%) , Pasteurells spp. (5.00%) and Pseudomonas aeruginosa (1.66%).
Most of the Staphylococcus spp., Streptococcus spp. and C. pyogenes
strains were sensitive to carbenicillin, gentamycin , kanamycin, and
erythromycin, but resistant to colistin and sulphamethoxazole. The other
mastitis pathogens like Enterobacter, Micrococcus, Pasteurella spp. and
Ps. aeuroginosa isolates were showed variable pattern of sensitivity to the
antimicrobial agents.
558 Comparison of Pathogens and Antimicrobial Susceptibility of
Isolates from Conventional and Robotic Milking Herds in
Korea
D. Kim, S.Y. Jeoung, S.J. Ahn
Kangwon National University, School of Veterinary Medicine,
Chuncheon, Kangwon, South Korea,
In Korea, robotic milking system is introduced about 2 years before.
However, mastitis control program on the robot milking dairy herds are
not fully understood. An observational study was conducted to compare
the pattern of pathogens and the antimicrobial susceptibility of
Staphylococcus spp. from 8 conventional (pipeline of parlor milking) and
8 robotic milking dairy herds. All herds composed with Holstein cows and
the robotic milking herds are using robotic milking system for at least 1
year before the start of this study. For each robotic milking farm, a
neighboring conventional dairy farm served as a control. After bulk tank
milk samples were collected, samples cultured on blood-esculin agar and
Baird-Parker agar. The cultured staphylococci colonies were identified as
Staphylococcus aureus and coagulase negative Staphylococcus (CNS)
by tube coagulase test. Regardless of the milking system, Staphylococcus
aureus was mainly cultured from the dairy farms in which teat dipping is
not completely conducted and Streptococcus uberis was cultured from the
farms in which udder washing was not completely conducted. The total of
119 Staphylococcus spp isolates was tested for minimum inhibition
concentration (MIC) against 14 antimicrobial agents by microdilution
method. The concentration that inhibits 90% (MIC90) of the analysed
strains in micrograms per mililiter, for S. aureus were 0.5, 256, 16, 4, 1,
0.25, 1, 32, 8, 0.5, 64, 512, 1 and 0.25 to ampicillin, bacitracin,
cephalothin, chloramphenicol, norfloxacin, erythromycin, gentamicin,
kanamycin, oxacillin, penicillin, streptomycin, sulphamethoxazole,
tetracycline, and vancomycin, respectively. And the MIC 90 values for
CNS were 1, 64, 0.5, 4, 1, 0.25, 0.5, 2, 0.5, 0.5, 4, 1024, 16 and 0.5 to
ampicillin, bacitracin, cephalothin, chloramphenicol, norfloxacin,
erythromycin, gentamicin, kanamycin, oxacillin, penicillin, streptomycin,
sulphamethoxazole, tetracycline, and vancomycin, respectively. Resistant
S. aureus isolates were found only to to ampicillin, bacitracin, oxacillin,
streptomycin, sulphamethoxazole, and penicillin on the basis of NCCLS
interpretive standards. Significant differences in antimicrobial
susceptibility between robotic and conventional milking dairies were
founded only to tetracycline.
Key words: robotic milking, Staphylococcus spp, antimicrobial
susceptibility, microdilution method, Korea
559 Use of Quarter Milk or Composite Samples for Diagnosis of
Subclinical Bovine Mastitis in Dairy Farms
C. Ribeiro 1 , D. Castro 1,3 , J. Galí 2 , P. Teixeira 1 J. Simoes 3
1 Centro Veterinário de Aveiro, Aveiro, Portugal
2 Grup Tecnic Veterinari S. L., Gerona, Spain
3 University of Trás-os-Montes e Alto Douro, Veterinary Science
Department, Vila Real, Portugal
Characterisation of pathogenic flora from composite milk (CM) samples
of subclinical intramammary infected cows is frequently performed,
instead of quarter milk (QM), in part due to economic reasons. One QM
or CM samples are also used in cows with only one QM to positive
California Mastitis Test (CMT). The aim of present work was to compare
pathogenic flora between QM and CM samples from cows with one
positive CMT quarter. Twenty Holstein-Friesian cows positive CMT in
one quarter were randomized from 3 dairy farms. Both QM (positive
CMT) and CM samples were collected in each cow. Somatic cell count
(fossmatic) and microbiologic analysis (Plate Count Agar) were
performed. Staphylococcus aureus were isolated in 35% (7/20), Streptococcus
uberis in 20% (4/20) and Streptococcus agalactiae in 10% (2/20)
of cows. Remained cows were affected by others contagious or environmental
microorganisms, including fungi. Pathogenic flora was observed
in QM but not in CM in 30% (6/20), in CM but not in QM in 5% (1/20) of
cows, similar in 15% (3/20) and different in 50% (10/20; P