Changes in the Secretion of Anti-Inflammatory Cytokines and Acute-Phase Proteins in the Uterus after Artificial Insemination in the Mare.
Authors: Wojtysiak Katarzyna, Ryszka Wojciech, Stefaniak Tadeusz, Król Jarosław, Kozdrowski Roland
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Artificial insemination triggers a consistent inflammatory response in the equine uterus, characterised by increased polymorphonuclear cell (PMN) infiltration and elevated concentrations of the anti-inflammatory cytokine IL-1RA and the acute-phase protein serum amyloid A (SAA) within 7 hours post-insemination, regardless of whether fluid was present in the uterine lumen before breeding. Wojtysiak and colleagues examined uterine lavage fluid in 25 mares stratified by their pre-insemination ultrasound findings—those with no fluid before or after AI, those developing fluid post-AI, and those with persistent fluid—to characterise the endometrial immunological response. All three groups demonstrated similar magnitude PMN influx and cytokine/acute-phase protein elevation following insemination, indicating a uniform uterine reaction to the insult of breeding. Notably, the presence of intrauterine fluid during estrus did not correlate with heightened PMN counts, though it appeared to influence baseline IL-1RA production prior to insemination. These findings support the interpretation that the post-insemination inflammatory cascade represents a normal physiological response to semen deposition rather than pathology, though practitioners should recognise that mares presenting with pre-existing intrauterine fluid may demonstrate altered baseline immune markers that warrant monitoring through subsequent breeding cycles.
Read the full abstract on PubMed
Practical Takeaways
- •Routine detection of uterine fluid before artificial insemination may not be predictive of post-insemination inflammatory response in mares
- •All mares mount a similar anti-inflammatory cytokine response after artificial insemination, suggesting the uterus has a standardized physiological mechanism to manage the insemination procedure
- •Pre-existing uterine fluid during estrus warrants monitoring of IL-1RA levels but does not necessarily indicate abnormal post-insemination response patterns
Key Findings
- •All mares showed significant increase in polymorphonuclear cells (PMN) 7 hours after artificial insemination regardless of pre-insemination uterine fluid status
- •Serum amyloid A (SAA) and interleukin-1 receptor antagonist (IL-1RA) concentrations increased significantly 7 hours post-insemination across all groups
- •Presence of intrauterine fluid during estrus did not correlate with PMN influx but did impact IL-1RA production
- •The endometrial inflammatory response to artificial insemination is consistent across mares with different baseline uterine fluid statuses