title: Comparative antibiogram of coagulase-negative Staphylococci (CNS) associated with subclinical and clinical mastitis in dairy cows.
abstract: OBJECTIVE
  The present study was planned to determine the in vitro antibiotic susceptibility of coagulase-negative Staphylococci (CNS) strains isolated from clinical and subclinical cases of mastitis in dairy cows. Antibiotic sensitivity profile will be helpful to recommend early therapy at the field level prior to availability of CST results.
  
  
  METHODS
  The milk samples from cases of clinical mastitis received in Mastitis Laboratory, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana and those of subclinical mastitis collected during routine screening of state dairy farms, were subjected to microbial culture. Identification of CNS organisms was done by standard biochemical tests. Antibiotic sensitivity testing, based on 30 antibiotics belonging to 12 groups, was done on 58 randomly selected CNS isolates (clinical isolates: 41, subclinical isolates: 17).
  
  
  RESULTS
  Isolates were highly susceptible to chloramphenicol (98.3%), gentamicin (93.1%), streptomycin (91.4%), linezolid (91.4%), ceftixozime (87.9%), cloxacillin (86.2%), clotrimazole (86.2%), bacitracin (86.2%), enrofloxacin (84.5%) and ceftrioxone + tazobactum (70.7%), while resistance was observed against amoxicillin (77.6%), penicillin (75.9%), ampicillin (74.1%) and cefoperazone (51.7%). Overall, isolates from clinical cases of mastitis had a higher resistance than subclinical isolates.
  
  
  CONCLUSIONS
  CNS isolates were susceptible to chloramphenicol, gentamicin and streptomycin, while higher resistance was recorded against routinely used penicillin group.
authors.affiliation: Department of Veterinary Medicine, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana - 1410 04, Punjab, India.
authors.forename: B K
authors.initials: BK
authors.lastname: Bansal
authors.affiliation: Department of Veterinary Medicine, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana - 1410 04, Punjab, India.
authors.forename: D K
authors.initials: DK
authors.lastname: Gupta
authors.affiliation: Department of Veterinary Medicine, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana - 1410 04, Punjab, India.
authors.forename: T A
authors.initials: TA
authors.lastname: Shafi
authors.affiliation: Department of Veterinary Medicine, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana - 1410 04, Punjab, India.
authors.forename: S
authors.initials: S
authors.lastname: Sharma
keywords: antibiotic; coagulase-negative staphylococci; cows; culture and mastitis