Evaluation of the Bactericidal Effect of Nebulized Silver Nanoparticles on Common Respiratory Bacteria in Horses- In Vitro Studies.

The research study is aimed at assessing the potential efficacy of nebulized silver nanoparticles in combating common equine respiratory bacteria. The findings indicate that silver nanoparticles effectively inhibit bacterial growth, raising the prospect of their use as an alternative therapy for respiratory disorders in horses.

Background and Purpose of Research

• The study starts with the concern over increasing antimicrobial resistance in both human and veterinary medicine.
• Bacteria have been found to be a significant factor in the respiratory disorders in horses.
• The antibacterial properties of silver are well-documented, hence its use in various veterinary therapeutic applications, such as wound dressings.
• The aim of the study is to evaluate the bactericidal effects of nebulized silver nanoparticles (AgNP) on two prominent equine respiratory bacteria: Streptococcus equi subsp. zooepidemicus and Actinobacillus equuli subsp. equuli.

Methodology

• This study employed an antimicrobial susceptibility test over time, observing turbidity in a liquid broth.
• The bacterial growth inhibition was tested after instillation or nebulization of varying concentrations (low, high) of AgNPs on an agar plate.

Results

• Both types of bacteria showed sensitivity to the AgNPs.
• After 8 hours, growth was susceptible even at a dilution of 1:4 for A. equuli and 1:8 for S. zooepidemicus. Further susceptibility was observed after 24 hours at 1:256 dilution for both kinds of bacteria.
• Bacterial growth was partially inhibited at low concentrations and completely inhibited at high concentrations of instilled AgNP.
• After nebulization, bacterial growth was completely inhibited at low concentrations for A. equuli and high concentrations for S. zooepidemicus.

Conclusion

• The results suggest that nebulized AgNP could offer a novel therapeutic approach against bacterial respiratory disorders in horses.
• However, the researchers note that further studies are needed to verify the in vivo potential and toxicity of nebulized AgNP. They insist on the need for more extensive research before any practical application can be implemented.