PURPOSE: To obtain an antimicrobial agent for animals, containing racemic modification or 3S-isomer of a pyrido[1,2,3-de] [1,4]benzoxazine derivative or salt or hydrate thereof as an active ingredient, having a wide range of antimicrobial activity and useful for bovine colibacillosis, etc.
CONSTITUTION: An antimicrobial agent containing racemic modification or 3S-isomer of a compound expressed by the formula [R is 1-6C alkyl (except that R is methyl in the case of the racemic modification)], a salt or hydrate thereof as an active ingredient. The compound expressed by the formula is directly orally administered or mixed in drinking water or a feed and orally administered. Furthermore, there is a method for administration by injection, etc. The dose thereof is normally 1-200mg, preferably 5-100mg based on 1kg body weight of an animal per day.
TAKEI MASAKAZU
KATO MASAHIRO
MIURA TADAYOSHI
YOSHIOKA TOSHIYUKI
