Haematological profile in foals during the first year of life

Area of Science:

• Veterinary Medicine
• Equine Health
• Hematology

Background:

• Foal hematological values are dynamic during the first year of life.
• Accurate diagnosis and care for foals require updated, age-specific reference intervals (RIs).
• Existing RIs may not reflect the significant physiological changes in young horses.

Purpose of the Study:

• To establish updated 95% reference intervals for 13 hematological values in foals.
• To track changes in these hematological values from day 2 to day 365 of life.
• To provide clinicians with essential data for diagnosing and treating foals.

Main Methods:

• Blood samples were collected from clinically healthy foals at 2, 7, 14, 30, 90, 180, and 365 days of age.
• Thirteen key hematological parameters were analyzed.
• Reference intervals were determined using a bootstrapping method, and changes over time were assessed with the Friedman test.

Main Results:

• Updated RIs were calculated for all 13 hematological values across different age groups.
• Significant increases in white blood cell counts (day 2-90) and lymphocyte counts (day 2-180) were observed.
• Mean corpuscular hemoglobin and mean corpuscular volume showed significant decreases (day 2-90).

Conclusions:

• Normal hematological values in foals differ substantially from adult horses and change significantly during the first year.
• Clinicians must utilize age-based reference intervals for accurate assessment of foal health.
• This study provides critical, updated data to support evidence-based veterinary care for foals.