Failure of colostral immunoglobulin transfer as an explanation for most infections and deaths of neonatal foals.

This study examines the impact of insufficient transfer of immunoglobulin G (IgG) from mare to foal through colostrum, indicating it may be the primary cause behind infections and fatalities in newborn foals. The research findings suggest foals experiencing colostral IgG transfer failure are more likely to acquire infections.

Study Sample and Methods

• The study focused on 87 Thoroughbred foals who had been tracked for potential failure in colostral IgG transfer.
• Out of these, 9 were found to have a complete failure, 12 experienced a partial failure, and the remaining 66 were deemed to have a normal transfer.
• This failure in colostral IgG transfer was monitored by taking presuckle postpartum colostrum samples and examining the colostral IgG content.
• In addition, they studied 11 foals from various other sources who had died from infection before the age of two weeks to ascertain the levels of IgG in their system.

Findings

• Close to 78% of the foals experiencing complete colostral IgG transfer failure acquired infections that required therapy. The ratio was significantly lower in foals with partial failure, with only three requiring treatment for infections.
• Of the foals with normal transfer, only two developed detectable infections, thus underlining the link between IgG transfer and infection resistance.
• The researchers found that nursing problems accounted for only one case of IgG transfer failure.
• Low colostral IgG content explained 2 of the 4 colostral IgG transfer failures and 4 of the six partial failures.
• Out of the 11 foals who had died of infection before reaching two weeks of age, six had a failure in colostral IgG transfer, and four had partial failure.

Conclusions

• This research indicates that inadequate colostral IgG transfer from the mare to the newborn foals might be a significant reason behind neonatal foal infections and subsequent fatalities.
• Rather than nursing issues, low colostral IgG content seems to explain most IgG transfer failures. Foals that do not receive adequate IgG through colostrum are more susceptible to infections, requiring therapeutic interventions.