Selected laboratory parameters of thoroughbreds.

This research article investigates various blood parameters in healthy Thoroughbred horses to establish typical ranges of these markers. It also examines the differences in these blood variables between certain groups of horses, such as difference in performance, age, gender, and temperament; and finds variability in hormonal levels but uniformity within other parameters.

Details of Blood Parameters Examined

• The study investigated various hematological, blood chemical and serological values in 45 healthy Thoroughbreds that were in training.
• These values included measurements of red and white blood cell counts, haemoglobin concentration, haematocrit and differential cell counts.
• Serum concentrations of multiple ions and chemicals like sodium, potassium, chloride, urea, creatinine, total protein, albumin, inorganic phosphorus, bilirubin, iron, glucose, and magnesium were studied.
• The research also looked into various enzyme levels namely alkaline phosphatase, gamma-glutamyltransferase, lactate dehydrogenase, aspartate transaminase, alanine transaminase and creatine kinase.
• All the parameters were found to be within ranges reported previously for horses, indicating that the sampled Thoroughbreds were within normal, expected health ranges.

Comparison of Blood Variables Among Horse Groups

• There was no significant difference found in haematocrit levels when comparing horses of different performance levels or age groups.
• However, noticeable differences in haematocrit were observed between male and female horses, as well as between quiet horses and excitable ones — with females and excitable horses displaying higher haematocrit concentrations.
• On the other hand, red cell potassium concentration did not differ significantly between horses of different performance.

Hormonal and Other Blood Values

• Several hormones were also measured, including cortisol, insulin, parathormone, and aldosterone, and their concentrations varied among the subjects.
• Vitamin B12 concentrations exceeded 1400 pmol l-1 in the blood samples tested, and blood lead concentrations were consistently below 15 ug l-1, indicating the absence of lead toxicity in the horses.
• There was a note that a proportion (33.3%) of the horses were carriers of babesiosis, a type of horse malaria. However, the laboratory findings in these horses did not deviate from those in the other horses. This implies that the carrier state of babesiosis did not significantly affect the standard blood parameters being investigated in these Thoroughbred horses.