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Background: Staphylococcal mastitis is a major cause of concern to the dairy industry in India and several countries worldwide. Though Staphylococcus aureus is the major cause, coagulase negative staphylococcal species (CoNS) are being increasingly reported in recent years. Aims: To investigate the incidence of coagulase negative staphylococcal species in bovine mastitis. Methods: Isolation of staphylococci was carried out from 237 milk samples of cows and She buffaloes with clinical and subclinical mastitis from different regions of Andhra Pradesh and Karnataka. CoNS isolates were identified by tube coagulase test using fresh rabbit plasma and coagulase gene PCR. We employed the biochemical test scheme published elsewhere previously for identification of the CoNS isolates up to species and subspecies levels. Seven representative isolates were identified by 16S rDNA sequencing to check the accuracy of biochemical test based identification. Results: The CoNS constitute the majority of the staphylococcal isolates from mastitis (80/125, 64%) in this region. Using biochemical test scheme, the CoNS isolates from bovine mastitis were identified as S. cohnii sub sp. cohnii, S. simulans, S. capitis sub sp. capitis, S. cohnii sub sp. xylosus, and S. lugdunensis. The CoNS species S. schleiferi, S. haemolyticus, S. sciuri, S. xylosus, S. chromogenes, and Macrococcus epidermidis were identified by 16S rDNA sequencing. Conclusion: The 16S rDNA sequencing is the appropriate method for the identification of CoNS species. This study highlighted coagulase negative staphylococcal species as possible etiological agents of mastitis. [ABSTRACT FROM AUTHOR]

The present study was carried out to characterize beta-lactam resistance in Escherichia coli isolated from healthy and diarrhoeic dogs. A total of 93 E. coli were isolated from the rectal swabs of 136 dogs (60/92 of healthy dogs and 33/44 of diarrhoeic dogs). Predominant serotypes detected include rough (19 isolates), O141 (5), O9 (2), O126 (2), O128 (2), O15, O20, O35, O49, O63, O85, O101, O116, O117, O118, O119 (1 isolate each) and the rest of 52 isolates were untypable (UT). Disc diffusion method revealed resistance to cefotaxime (41.9%), ceftriaxone (34.4%), ceftazidime (30.1%) and aztreonam (18.2%). Overall frequency of extended spectrum beta-lactamase (ESBL) phenotype was found to be 29% (27/93). Beta-lactamase genes detected include blaAmpC (86.0%), blaSHV (30.1%), blaCTX-M group-1 (19.3%), blaTEM (17.2%), blaOXA (13.9%) and blaCTX-M group-2 (7.5%). The study revealed resistance to commonly prescribed beta-lactams, with ESBL phenotype in E. coli of canine origin in Andhra Pradesh, India. [ABSTRACT FROM AUTHOR]