O.A.Chiesa, J.D.von Bredow, P.Chamberlain, J.O.Peggins, R.Idowu, K.E.Moulton, CVM, FDA, Laurel, MD
Gentamicin, an aminoglycoside antibiotic, has often been used in human medicine to treat uterine infections following child-birth. The nursing newborn may be able to absorb gentamicin from the milk of the antibiotic treated mother. The sparse exposure data reported for the human newborn may be expanded significantly studying gentamicin transfer from mother to offspring using the dairy cow and her newborn calf as a large animal model for the mother and her new born infant. In these studies Gentamicin was administered daily to a Holstein cow by i.v. infusion for seven consecutive days following birth of her calf. Analysis of gentamicin in plasma and milk samples collected from the cow indicated diffusion of gentamicin into the milk. Plasma samples collected from the newborn calf also demonstrated significant oral absorption of the drug after each nursing with milk from the gentamicin treated cow.