Transfer of tumour necrosis factor-α via colostrum to foals

This study aimed to determine whether TNF-alpha is transferred to equine neonates via colostrum and the relationship between TNF-alpha and IgG concentrations in the equine neonate. Colostrum, presuckle and postsuckle foal serum samples were collected from healthy mares and their foals. Equine TNF-alpha ELISA and IgG SRID kits were used to determine the concentrations of TNF-alpha and IgG, respectively. Statistical analysis was performed using the Spearman rank correlation. TNF-alpha concentrations in all presuckle foal serum were below the limit of detection in 15/16 foals and increased in postsuckle foal serum to a mean concentration of 7.7 x 104 pg/ml. TNF-alpha concentrations in postsuckle foal serum and colostrum showed significant correlation (rho=0.668; P=0.005). However, TNF-alpha and IgG concentrations in colostrum or postsuckle foal serum did not correlate (rho<-0.016; P>0.05). Ratios of TNF-alpha/IgG in colostrum or postsuckle foal serum showed significant correlation (rho=0.750; P=0.0008). These results indicate that TNF-alpha is transferred to the foal via colostrum absorption and may play a role in early immunity