Antimicrobial Resistance in Equine Reproduction

Area of Science:

• Veterinary Medicine
• Microbiology
• Reproductive Biology

Background:

• Antimicrobial resistance (AMR) is a growing concern, developing from both low-level and therapeutic antibiotic exposure.
• AMR has been documented in the equine reproductive tract globally over the past two decades.

Purpose of the Study:

• To review antimicrobial resistance (AMR) in the equine reproductive tract.
• To investigate the role of antibiotics in semen extenders as a potential source of AMR.
• To explore the impact of AMR on equine fertility and sperm quality.

Main Methods:

• Comprehensive literature review of studies on equine reproductive tract infections and AMR.
• Analysis of bacterial contamination in semen during collection and processing.
• Evaluation of the effects of antibiotics in semen extenders on bacterial growth and sperm viability.

Main Results:

• AMR in equine uterine and vaginal bacteria is reported worldwide.
• Contamination of semen with bacteria occurs during collection and processing.
• Antibiotics added to semen extenders, while inhibiting some bacterial growth, can negatively affect sperm quality and contribute to AMR.

Conclusions:

• Antibiotic use in equine semen extenders poses a risk for AMR and may compromise sperm quality.
• Current practices contradict recommendations for prudent antibiotic use.
• Alternative methods, such as physical separation of bacteria and sperm, warrant further investigation, including colloid centrifugation.