Impact of age on antibiotic distribution and efficacy in calves
Keywords:calves, antibiotics, pharmacokinetics, therapy
Calfhood diseases have a major economic impact on beef and dairy operations, due to the costs associated with mortality, treatment, and the long-term effects on growth and performance. With very limited approved drugs for use in "pre-ruminant” calves and heifers, questions remain about the effectiveness of these drugs in young animals. It is important to prevent unnecessary use of antibiotics in calves to limit the development of resistant bacteria and residues, as well as take into account the developmental changes that occur in neonatal calves that would affect the distribution, therefore efficacy of selected drug therapy. The purpose of this article will give an overview of the effects of age on absorption, metabolism, distribution, and elimination of commonly administered drugs and its impact on efficacy in different ages of calves.