Inhibition of avian clostridia or pathogenic E. coli by enterococci an
d by organic acids was studied. The administration of Enterococcus fae
cium significantly decreased clostridial counts adhering to the crop w
all as well as in the caecum content. The effect of acidifiers - aceti
c, sorbic, formic and citric acids was investigated. The most effectiv
e acidifier was formic acid in 0.25% concentration, which inhibited gr
owth of avian clostridia. The applicability of probiotics in space bio
logy is discussed.