Effects of 2 preparation methods and long-term storage on structural integrity and bacterial loads of equine amnion.

The research examines the effects that different tissue preparation and storage methods have on the structural integrity and bacterial contamination risk of equine amnion. The findings suggest that the methods tested in the study ensure minimal bacterial contamination and structural alteration in amnion stored up to 12 months.

Research Background

• The study aims to investigate the effects of various tissue preparation and long-term storage techniques on structural integrity and bacterial contamination risk in equine amnion, also called the amniotic membranes. These membranes come from eight healthy mares and were used in 440 tested samples for the study.

Methods Used in the Research

• The tissue samples for baseline bacteriology and histology were taken after debris removal.
• The remaining tissue was then divided and processed with one of two solutions: 0.05% chlorhexidine or, a mixture of 2% iodine and 0.25% acetic acid.
• The processed amnion samples were then assigned to one of nine combinations of preservation media – saline, chlorhexidine, or acetic acid, and storage temperatures – 4 °C, -20 °C, or -80 °C.
• These samples were sent for quantitative bacteriology and histopathology at intervals of 1 week, 4 weeks, and 3, 6, 9, and 12 months.

Research Findings

• Results indicate that baseline bacterial levels ranged from less than 200 to more than 150,000 colony-forming units (cfu)/mL.
• No potentially harmful bacteria found in the baseline samples were cultured throughout the study, meaning the preparation and storage methods successfully prevented their growth.
• A small amount of nonpathogenic bacteria, most commonly Bacillus, were found across all storage conditions. These bacteria posed no threat to the health or lifespan of the cells.
• In addition, the tissue structures were minimally affected by the processing protocol, storage temperature, or storage duration.

Conclusions

• From these findings, the researchers concluded that the two processing methods tested in this study resulted in minimal bacterial contamination and negligible structural integrity loss in equine amnion up to 12 months of storage at temperatures of 4 °C, -20 °C, or -80 °C.
• The research suggests that amnion collected during the foaling season could be stored for up to 12 months without any significant bacterial contamination or structural alterations, ensuring a greater shelf life and usability of these cells for further research or clinical use.