A prospective study of septicaemia in colostrum-deprived foals.

Fourteen mares and their foals were attended at parturition. After mare-foal bonding, 8 colostrum-deprived (CD) foals were removed from their dams, deprived of colostrum, and provided with an alternative milk source for the first 24 h of life. The mares were milked out every 2-4 h during this period to remove colostrum, after which the CD foals were returned to their mares and allowed to nurse. Six colostrum-fed (CF) foals were allowed to suck colostrum in the normal manner. Foal serum IgG concentration was determined by single radial immunodiffusion (means, CD = 0 mg/dl; CF = 1,508 mg/dl). Accepted methods were used to minimise infections in the neonatal foals. Of the 8 CD foals, 7 demonstrated clinical signs of sepsis. Septicaemia was confirmed in 5 of the 7 septicaemic CD foals by ante-mortem blood culture or by culture of tissue at necropsy. Organisms isolated included: Actinobacillus equuli, Escherichia coli, undifferentiated coliforms, Pseudomonas spp., and Actinomyces pyogenes. Clinically ill foals were treated with antimicrobial drugs, intravenous fluid therapy, flunixin meglumine, and anti-endotoxin hyperimmune serum. Three septicaemic CD foals survived. Four of 7 septicaemic CD foals died or were destroyed. Post-mortem lesions included bacterial embolic pneumonia, glomerulonephritis/nephritis, lymphoid depletion/atrophy, splenic and lymphoid necrosis, hepatitis, septic arthritis, and systemic bacterial embolism. None of the CF foals became septicaemic. One CF foal had foal heat diarrhoea and 1 CF foal had a serum IgG concentration of 160 mg/dl (i.e. failure of passive transfer), but both foals were otherwise normal.(ABSTRACT TRUNCATED AT 250 WORDS)