Influence of dystocia on white blood cell and blood neutrophil counts in mares.

This research article investigates the effects of dystocia, a difficulty in giving birth, on the white blood cell (WBC) and neutrophil counts of mares, and compares these results with normal foaling mares.

Research Demographics

• The retrospective study involved a total of 41 mares, aged 2 to 19 years, with varying breeds including draft, light, and pony.
• These mares were referred to two different veterinary hospitals due to complications in delivery, or dystocia.
• For control comparisons, blood cell counts of 10 normal foaling mares from two Pennsylvania breeding farms (Thoroughbred and Trakehner) and of 14 normal pony mares were retrospectively analyzed.

Research Methodology

• The researchers measured the total WBC and neutrophil counts at various intervals, from the time the mares were admitted to the hospital, up to 10 days after the foals were delivered.

Research Findings

• WBC and neutrophil counts slightly elevated beyond the normal range during the day of delivery among the mares that had normal parturition.
• The blood cell count gradually declined on the second day after birth and returned to their baseline values by the third day.
• No toxic neutrophils were found in mares that had normal deliveries.
• Conversely, mares that experienced dystocia had higher WBC count on the day of delivery, driven by an increase in neutrophil count. This phenomenon, known as neutrophilia with a left shift, indicates an infection or inflammation.
• A noteworthy fast decline in WBC and neutrophil count was observed in mares with dystocia compared to those with normal deliveries. By the third day, these mares had remarkably low WBC and neutrophil counts, known as leukopenia and neutropenia respectively.
• Leukopenia and neutropenia in dystocia mares persisted until the fifth day postpartum.
• Toxic neutrophils were found in several mares with dystocia, implicating the presence of bacterial infection or extreme inflammation.

Conclusion

• In conclusion, this study points to the impacts of dystocia on WBC and neutrophil counts in mares, with values reflecting an initial burst of immune response, followed by a quick reduction and resultant low levels of these cells. This pattern may be indicative of higher inflammatory or infectious conditions accompanying dystocia.