Pets have been recognized to play significant roles of companionship in the lives of humans. In fact, pets are regarded as “members of the family” in some households (Rauktis et al., 2017; McConnell et al., 2019), and their importance have interestingly led to an increase in the frequency of pet animal ownership with a simultaneous and exponential boom of the pet food industrial sector (Finisterra et al., 2021). Safe pet food is central to the well-being of companion animals (Gizaw et al., 2020). Improving and complying with hygienic practices in pet food manufacturing industries is an important key factor in preventing, reducing, or maintaining the safety and quality of pet food in order to protect companion animals from foodborne pathogens (Rani et al., 2017). This will be very significant in safeguarding public health and improving the general well-being of pets, including their human guardians/owners. However, the present boom in pet food industry is challenged with contamination of pet food by bacterial pathogens likely from raw materials, manufacturing equipment, the production process, storage, packaging, or even damage during transportation (Anturaniemi et al., 2019).

Coagulase-negative staphylococci (CoNS) are part of the natural microbiota of mammals and have emerged as opportunistic etiological agents of infections in immunocompromised individuals, patients with prosthetic implants and devices, oncologic and dialysis patients, and neonates (Vanderhaeghen et al., 2015; Gaerste-Díaz et al., 2018; Michalik et al., 2020; Silva et al., 2022). Although ubiquitous in nature, CoNS, especially multidrug-resistant (MDR) strains, have been reported to be an important threat to food safety (Gizaw et al., 2020). This calls for pet food assessment as potential vehicles of direct and indirect bacterial pathogen transmission to pets and humans. In addition, increasing antimicrobial resistance rates have been detected in CoNS, thus limiting therapeutic options (Becker et al., 2014). Methicillin resistance in CoNS (MRCoNS) is usually due to the expression of mecA gene that encodes an alternative penicillin-binding protein, PBP2a, which has a low affinity for β-lactams. The mecA and other types of mec (mecC, mecD) genes are located on a mobile genetic element called the Staphylococcal Cassette Chromosome mec (SCCmec) (Loncarić et al., 2019).

Recently, CoNS contamination of poultry by-products (chicken and turkey viscera, meat, bones, etc.) that are usually raw materials for pet food production has been reported (Pimenta et al., 2021). If good manufacturing practices are not observed during pet food production to completely eradicate these pathogens, they could be transmitted to pets, and in turn indirectly to humans, especially pet owners (Bottari et al., 2020). This can lead to a variety of infections, such as invasive endocarditis and osteomyelitis (Michalik et al., 2020). Reports on pet food contaminated by MDR bacterial pathogens are on a continued increase with significant public health risks (Jones et al., 2019). The pockets of studies on commercial pet food contamination focused mostly on Gram-negative bacilli pathogens harbouring clinically relevant antimicrobial resistance genes (ARGs) such as mcr-1, blaCTX-M-like, and blaOXA-like (Seiffert et al., 2014; Baede et al., 2017; Nüesch-Inderbinen et al., 2019).

Despite the increasing frequency of pet ownership and the current boom of the pet food industry in the last decade, studies focusing on the microbiological evaluation of pet food, especially MRCoNS are still scarce; thus, contributing to the underestimation of this group of pathogens with emerging public health significance. This study was therefore designed to investigate the co-resistance to methicillin and clindamycin among CoNS recovered from pet food in Brazil, and their carriage of virulence-encoding genes.