Fibrinogen levels and factor VIII activity. Lactobacillus casei was orally administrated at a dose of 109 cells for 2 d before challenge with the pathogen; C group were infected without previous treatment. (A) Fibrinogen levels and (B) factor VIII activity were studied. Results are expressed as means ± SD (n = 5 or 6). *Significantly different from the C group (p < 0.05).