ANTIMICROBIAL SENSITIVITY Vs ANTIMICROBIAL RESIDUE IN MILK IN CASE OF BOVINE MASTITIS -A STUDY.

The study was conducted on 26 nos. of milk samples of bovine depending on the history of ailing from clinical mastitis and scrutiny of same herd for subclinical mastitis. This study was cross sectional case control study. The 26 samples was chosen on the basis of positive reaction for White Side Test(WST), California Mastitis Test(CMT) and pH of milk. On the basis of field experience four(04) types of antibiotics has been taken into consideration such as Amoxicillin, Ceftriaxone, Tetracycline, Enrofloxacin. All the 26 samples are subjected to drug sensitivity test. The most effective antibiotic was Tetracycline(88.46%) followed by Enrofloxacin (65.38%), Amoxicillin (57.69%), Doxycycline (46.15%),Gentamicin (42.30%) and Ampicillin (34.61%). Microorganisms were mostly resistant to drug like Doxycycline, Gentamicin, Ampicillin, Ciprofloxacin, Ceftriaxone in increasing order of resistance. Here,drug sensitivity tests were done abiding the criteria of CLSI-2014.Hence it is suggested that the line of treatment should be based on antibiogram study of various isolates of bovine milk acquired from bovine mastitis. But, if the use of antibiotics is necessary as in prevention and treatment of animal disease like mastitis, a with holding period must be observed until the residues are negligible or no longer detected. Here, this study also target the residue of four(04) antibiotics like Tetracycline, Amoxicillin, Ceftriaxone and Enrofloxacin through HPLC, which yields a significant outcome , i.e., all milk samples show the significant level of residue of Ceftriaxone(100%) followed by Amoxicillin(46.15%), Enrofloxacin(34.61%) and Tetracycline(15.38%). This result may be due to indiscriminate and irrational use of such drugs, which may out of count in scientific point of view. Besides it is observed that the drugs which are resistant to the micro organisms are found as residue in milk, may be due to its unutilization on micro organism biochemically. Selection of antibiotics and its rational use may cure this mastitis like problem and resist evolving of resistant micro-organisms and reduce the existence of toxic level antibiotic residues in the milk and milk products. Though this is a pilot study which warrants long term prospective study to strengthen this view.