**3. Antibiotic resistance among companion livestock**

MRSA was identified for very first time in 1972, from mastitis-affected cows and then MRSA from human origin was isolated from dairy cows [37]. MRSA has been found in almost all tame animals since its first observation. Major associative factor for MRSA found to be wound infections and post-operative skin infections, especially in dogs, cats, horses, and rabbits [38, 39]. In one of the study of milk-producing bovines in Mathura reported that MRSA in India was shown to be *S. aureus* was found in 33.75% of subclinical mastitis and clinical mastitis cases among cattle than buffaloes [40]. Tiwari *et al.* (2015) published *S. aureus* among different specimens from pigs, buffalo, dogs, goats, sheep, camels, and horses with different skin disorders of all companion livestock's [41]. *S. aureus* isolates from healthy cow milk samples were found to be resistant to erythromycin (75%), penicillin (100%), and amoxicillin (100%), but susceptible to cloxacillin (100%), neomycin (100%) oxacillin (100%), and ciprofloxacin (83.33%) [42]. MRSA study by Kumar *et al.* (2017) was shown to be penicillin and oxytetracycline resistant (88% each), cefoxitin resistant (75%), cotrimoxazole resistant (62%), and amoxyclav resistant (62%) in antimicrobial susceptibility screening conducted in study on 136 skin and nasal samples collected from cows and buffaloes. Vancomycin resistance was discovered in 3 (16.7%) MRSA isolates from buffalo isolates [43].

### **3.1 Transmission of antimicrobial resistance from livestock to humans**

Livestock's colonization with antimicrobial resistance organisms and human infections due to drug resistant organisms are appearing as a potential threat worldwide. MRSA is now regarded as an emerging zoonotic agent. Over the last

### *Antimicrobial Resistance in Staphylococci Special Emphasis on Methicillin Resistance… DOI: http://dx.doi.org/10.5772/intechopen.99830*

two decades, MRSA has been noticed in the population. Novel MRSA strain known as livestock-associated MRSA (LA-MRSA) has been discovered in farmers and fodder producing animals. [44, 45]. In previously literature, MRSA sequence form was known as non-typable MRSA (NT-MRSA) lacking property of typed using pulsed field gel electrophoresis(PFGE) with SmaI. ST398 isolated as a prevalent sequence type in the agricultural animals, especially pigs and veal calves, as well as persons who worked with these animals [46]. Carriers of MRSA are at risk of developing an MRSA (wound) infection following skin damage (scarification) or surgery. The mode of MRSA transmission from animal to human is frequently inferred from parallel genetic observations including isolates obtained from *in-vitro* experiments [47, 48]. Another study revealed that incorporation of mecA gene encoding penicillin-binding protein 2a into the *Staphylococcal* cassette chromosome *mec* (SCCmec), are considered as factors in the drug resistance of *S. aureus* strains. There is evidence that methicillin-sensitive *S. aureus* strains inherited the SCC mec factor from coagulase-negative staphylococcal strains and subsequently became methicillin-resistant [49].

Reports on the carriage rate of pigs and the farmers associated with those pigs in Netherland divulge a high isolation of MRSA ST398 whereas the same sequence lineage has been observed in the dirt samples from the pig propagation space and eatable samples in Austria. In China, LA MRSA ailment is considered as an professional pitfall for farm workers, LAMRSA in the animal handlers may ranges from region to region i.e., 19.2% in Taiwan, 5.5% from Malaysia and 15% in China [50, 51]. Globally, MRSA percentage increased by 20% in all WHO sectors while 80% increase in few countries [52].

Factors - The emergence and spread of LA-MRSA is attributed to antimicrobial resistance upsurge. However hygiene along with under-described or poorly investigated factors i.e., farm dimensions, cultivation system, use of bioinoculants, and in-feed microelements also contributing the emergence of AMR [53]. Other than *S. aureus* some species of Coagulase negative staphylococci (CoNS) may also be transferred from animals to humans in contact with them, evidence found from a study (Jangra et al. 2018) that revealed some pathogenic strains of Coagulase negative staphylococci (*Staphylococcus warneri* and *Staphylococcus scuiri*) that are announced as a particular pathogen linked with animal origin however their isolation from the human subjects associated with them were also be detected. These results further strengthening the probability for the transmission of such pathogenic species from the domesticated animals [54].
