Complement activity and selected hematologic variables in newborn foals fed bovine colostrum.

The research study investigates the blood characteristics and immune responses in newborn foals that consume bovine colostrum, compared to those that nurse from their mothers directly.

Study Design

• The study analyzed 5 newborn foals who received bovine colostrum (named as the principal group) and six foals who nursed from their mothers (the control group).
• The authors compared serum complement activity and selected hematologic variables between these two groups.
• Besides, the bovine colostrum was scrutinized for anti-equine antibodies, which are antibodies that can recognize and bind to molecules from horses.

Findings

• Both groups showed low serum hemolytic and conglutinating complement activities, which are part of the immune response, before the intake of colostrum.
• These complement activities increased similarly in both groups, achieving adult levels between 1 and 3 weeks post-birth.
• Interestingly, the bovine colostrum led to agglutination (clumping together) of red blood cells (RBCs) in the principal group of foals, but it did not lead to hemolysis (breaking down of RBCs).

Impact of Bovine Colostrum and Physiological Anemia

• All known equine blood group alloantigens (protein markers on the surface of RBCs) were present in the blood from foals of the principal group. Despite this, no hemolysis occurred after the administration of bovine colostrum.
• Both groups experienced physiological anemia (low red blood cell count or hemoglobin levels) during their first week of birth, which is a common occurrence in newborns as their bodies adjust to life outside the womb.
• The resistance of red blood cells to bursting when placed in a solution of reduced osmotic concentration (erythrocyte osmotic fragility) didn’t change in the principal group before and after colostrum ingestion. However, a significant reduction in erythrocyte osmotic fragility was observed at 36 hours post-birth in foals that consumed homologous (same species) colostrum.

Conclusion

The study determines that the consumption of bovine colostrum by foals impacts their erythrocyte activity and immune response, without provoking harmful effects. These findings may have implications for the feeding and management of newborn foals, particularly in scenarios where a mother’s milk is not available. However, future research is necessary to further understand these complex biological processes.