Bacterial Skin Infections in Livestock and Plant-Based Alternatives to Their Antibiotic Treatment

SIMPLE SUMMARY: Bacterial skin infections in livestock are among the factors promoting antibiotic use. The use of antimicrobial agents has been shown to contribute to the increased prevalence of resistant bacterial strains. The rapid emergence and spread of resistant bacteria are a worldwide problem. With regard to the development of bacterial antibiotic resistance, phytochemicals are considered as possible substitutions of antimicrobial agents. In the field of plant-derived extracts, a number of studies deserve review because of the severity of the effects of resistant species of bacteria. This review presents current knowledge of plant-derived compounds, focusing on their modes of antibacterial action against pathogenic bacteria causing skin infections in livestock. Finally, great attention is given to specific plants that have antibacterial effects and are used in the healing and wound treatment of farm animals. ABSTRACT: Due to its large surface area, the skin is susceptible to various injuries, possibly accompanied by the entrance of infective agents into the body. Commensal organisms that constitute the skin microbiota play important roles in the orchestration of cutaneous homeostasis and immune competence. The opportunistic pathogen Staphylococcus aureus is present as part of the normal biota of the skin and mucous membranes in both humans and animals, but can cause disease when it invades the body either due to trauma or because of the impaired immune response of the host. Colonization of livestock skin by S. aureus is a precursor for majority of bacterial skin infections, which range from boils to sepsis, with the best-characterized being bovine mastitis. Antibiotic treatment of these infections can contribute to the promotion of resistant bacterial strains and even to multidrug resistance. The development of antibiotic resistance to currently available antibiotics is a worldwide problem. Considering the increasing ability of bacteria to effectively resist antibacterial agents, it is important to reduce the livestock consumption of antibiotics to preserve antibiotic effectiveness in the future. Plants are recognized as sources of various bioactive substances, including antibacterial activity towards clinically important microorganisms. This review provides an overview of the current knowledge on the major groups of phytochemicals with antibacterial activity and their modes of action. It also provides a list of currently known and used plant species aimed at treating or preventing bacterial skin infections in livestock.