Recent Trends in <i>S. aureus</i> and <i>E. coli</i>-Based Endometritis, and the Therapeutic Evaluation of Sodium Alginate-Based Antibiotics and Nanoparticles

Postpartum infection of the uterus by pathogenic bacteria is exacerbated due to a lack of sufficient epidemiological studies and evidence-based therapeutics. Therefore, this study was planned to find the prevalence, risk factors, and drug-resistance profile of <i>S. aureus</i> and <i>E. coli</i> isolated from bovine endometritis and to evaluate the antibacterial potential of sodium alginate-based antibiotics and nanoparticles. The study revealed 34.21% <i>S. aureus</i> and 31.57% <i>E. coli,</i> whereas most of the assumed risk factors presented significant association in this study. <i>S. aureus</i> showed the highest resistance against fusidic acid (60%) and cefoxitin (50%), while the highest resistance in <i>E. coli</i> was found against fusidic acid (60%), gentamicin (60%), chloramphenicol (50%), and cefoxitin (50%). Tylosin coupled with MgO nanoparticles stabilized in sodium alginate gel (Tylo + MgO + gel) presented significantly lower minimum inhibitory concentration (MIC) against <i>E. coli</i>, showing 13.88 ± 4.51 µg/mL after 24 h incubation. On the other hand, gel-based preparations showed MIC as 31.25 ± 0 µg/mL (Tylo + gel + MgO) and 26.04 ± 9.02 µg/mL (Tylo + Gel) against <i>S. aureus</i>. Generally, the MICs of non-gel-based preparations were significantly higher against bacteria except ampicillin against <i>S. aureus</i> in this study. The toxicity analysis of MgO nanoparticles presented 20–80% mortality of snails against a wider range of 0.01 mg/mL–10 mg/mL. The histopathological parameters concluded MgO nanoparticles safe to use on off targets. The current study thus concludes the rise in antimicrobial resistance while the gel-based products appearing as effective antimicrobials with sufficient safety margins for off-targets. The study thus invites further investigation for the development of suitable and affordable modified therapeutics for better health and production of animals.