One ml 106 CFU (colony formation units) per ml suspension of Staphylococcus aureus was inoculated to one udder of the lactating goats to induce mastitis. Fifteen lactating goats were randomly divided into three groups according to different routes of administration. With cross-over design, comparative pharmacokinetic study was conducted in healthy and mastitis goats followed by single intravenous, intramuscular and intramammary administration of enrofloxacin at the dose of 2.5 mg·kg -1 body weight. Concent...