Effects of bovine colostrum, foal serum immunoglobulin concentration and intravenous plasma transfusion on chemiluminescence response of foal neutrophils.

The research investigates how bovine colostrum (the first milk cows produce after giving birth), the absorption of equine colostral immunoglobulins (proteins in a mare’s first milk), and a foal’s age affect the activity of their neutrophils (a type of white blood cell) and serum (the liquid part of blood). Specifically, it studies both the foal’s ability to engulf harmful cells and substances (phagocytic activity) and the ability of the serum to assist with this process (opsonic activity). The results show bovine colostrum stimulates these activities and that the functionality of foal neutrophils and serum opsonizing activity are related to their age and the concentration of Immunoglobulin G (IgG) in their bodies.

Research methodology / process :

• The study investigated nine healthy foals. Cells and serum were collected at various points in time during their first month after birth – specifically before suckling and at 7, 14 and 28 days of age.
• Of these nine foals, seven exhibited serum IgG concentrations above 600 mg/dl, while two had less than 350 mg/dl.
• The research also examined the phagocytic and serum opsonic activities of eight clinically ill foals with less than 400 mg/dl of IgG serum. These measurements were done before and after a plasma transfusion.
• Phagocytic and serum opsonizing activities were evaluated using a chemiluminescence (CL) assay after the addition of opsonized streptococci (bacteria treated to encourage phagocytosis).

Findings :

• Bovine colostrum had a positive effect on the CL of foal neutrophils, demonstrating that it stimulates their phagocytic activity.
• The ability of foal neutrophils to generate CL was found to vary with age. Neutrophils collected on day 14 generated more CL than adult neutrophils.
• Foal serum opsonizing activity was similar to that of adults if their serum IgG concentrations were above 600 mg/dl. If IgG concentration was below 350 mg/dl, their opsonizing activity was less significant.
• Both foal and adult neutrophils produced more chemiluminescence when post-transfusion foal serum was used as the source of opsonin than when pre-transfusion foal serum was used.
• The chemiluminescence of foal neutrophils collected before and after plasma transfusion did not differ when adult serum was the opsonin source. This suggests that the increase in CL following plasma transfusion was probably due to an increase in serum opsonizing activity.