Thromboelastography in healthy dairy cows

Area of Science:

• Veterinary Medicine
• Hemostasis and Thrombosis Research
• Dairy Cattle Health

Background:

• Coagulopathies are common in cows, necessitating reliable diagnostic tools.
• Thromboelastography (TEG) assesses whole blood coagulation, offering insights into hypocoagulability and hypercoagulability.
• Establishing species-specific reference intervals is crucial for accurate interpretation.

Purpose of the Study:

• To determine reference intervals for TEG in healthy dairy cows using kaolin activation.
• To investigate potential variations in TEG parameters based on lactation stage.
• To assess the stability of citrated whole blood samples for TEG analysis over time.

Main Methods:

• Sixty healthy Holstein-Friesian cows were grouped by lactation period (≤30, 31-99, ≥100 days postcalving).
• Thromboelastography was performed using a TEG 5000 analyzer with citrated whole blood and kaolin activation.
• Sample stability was tested for up to 100 hours at room temperature.

Main Results:

• Reference intervals were established: reaction time (2.2–6.2 min), coagulation time (0.8–2.0 min), angle α (58.2–81.8°), maximum amplitude (64.3–89.2 mm), and clot rigidity (9.2–41.2 dyn/cm²).
• No significant differences in TEG parameters were observed among the different lactation groups.
• No significant changes in TEG parameters were detected in samples stored for up to 48 hours.

Conclusions:

• The study provides essential reference intervals for TEG in dairy cows.
• Lactation stage does not appear to significantly influence TEG parameters in healthy cows.
• TEG samples are stable for at least 48 hours at room temperature, allowing for logistical flexibility.