Comparison of the Cytology Brush and Low Volume Lavage Techniques to Evaluate Endometrial Cytology for Diagnosing Endometritis in Chronically Infertile Mares

Endometritis is the most common cause of subfertility and infertility in mares that leads to great economical loss. Endometrial cytology (EC) is a reliable diagnostic tool, widely used to assess the health of the reproductive tract in both humans and domestic mammals. The aim of this study was to compare two techniques for the collection of EC samples in chronically infertile mares. Ten mares aged 4 to 20 were used. In each mare, samples for EC were collected first by cytology brush (CB) and then by low volume lavage (LVL) and stained using the Diff Quick stain. Each sample was assessed for the following parameters: background of the slides, quality and quantity of the cells obtained, number of inflammatory cells. Also, we assessed the number of operators, time and costs needed for each technique. More debris was noticed in the LVL samples, as well as a higher percentage of distorted cells. However, inflammatory cells were detected in all positive samples. Sampling by LVL required two to three operators and recovery of the lavage fluid was sometimes difficult. In conclusion, both techniques are accurate for the detection of uterine inflammation.