Equine haptoglobin: isolation, characterization, and the effects of ageing, delivery and inflammation on its serum concentration.

The primary aim of this study was to investigate haptoglobin (Hp), a type of protein present in horse’s blood, its function, characteristics, and how it is affected by ageing, delivery, and inflammation.

Isolation and Characterization of Equine Haptoglobin

• The research initially focused on isolating the haptoglobin from the serum of a horse. This process was accomplished using various techniques such as ammonium sulphate precipitation, anion-exchange chromatography and gel filtration.
• The isolated haptoglobin was then characterized. The research showed that it migrated to the alpha 2-globulin region when subjected to electrophoresis. It also showed that the isolated haptoglobin contained 2 fractions each having different molecular weights- 108,000 and 105,000, and each fraction is made up of 2 subunits.

Quantitative Measurement of Horse Serum Haptoglobin

• The researchers then moved on to quantitatively measure the amount of haptoglobin in the horse serum. To achieve this, they used the single radial immunodiffusion method, utilizing an anti-equine Hp serum.
• The findings showed that the concentration of this protein is highest in newborn foals and maintained a high level up to 12 months of age, after which it reduced gradually as the horse aged.
• The average Hp values were stated at 5.25 mg/ml in foals, 2.19 mg/ml in adult horses and 3.62 mg/ml across all ages of horses.

Effects of Delivery and Inflammation on Serum Haptoglobin Levels

• The study pointed out that serum Hp concentration in mares during the perinatal period was high four months pre-partum, spiked again at delivery, and then decreased to normal levels within a month after delivery.
• In the part of the study regarding inflammation, the researchers observed that serum Hp concentration in horses that had experimentally-induced inflammation started to rise immediately after the inflammatory treatment. The value peaked, reaching 1.5 to 9 times higher than the pre-treatment level, between 2 to 5 days post-treatment before decreasing back to normal within 4 weeks.
• These elevated Hp levels were also noted in horses with clinical signs of inflammation, proving the connection between inflammation and increased Hp concentration.