A comparison of intramammary and intravenous routes of administration of pencillin and the effects of Dimethyl sulfoxide (DMSO) on the distribution of pencillin by both administration routes

The distribution of Penicillin G Potassium administered intramammarily (IMM) and intravenously (IV) and the effects Dimethyl sulfoxide (DMSO) has on this distribution was investigated. In this study, cows were divided into four treatment groups. Cows in treatment group one were given penicillin in the right front quarter while cows in treatment group two were given penicillin plus DMSO in the right front quarter. Cows in treatment group three were given penicillin IV and cows in treatment group four were given penicillin plus DMSO IV. Data were obtained from analysis of milk and serum samples collected at 0, 30, 60, 90, 120, 240, 360, and 480 minutes following treatment. Differences in concentration of penicillin in serum and in milk from each quarter were the primary measurement responses.

The use of DMSO with IMM treatments did not significantly affect the concentration of penicillin in the milk. However, when DMSO was added with the IV administration of penicillin, there was a faster rate of removal of penicillin from the serum with a slight increase in penicillin in the milk samples. This increase in milk levels of penicillin was not highly significant. Since in each treatment group involving the use of DMSO increases in concentration of penicillin in milk were slight, it would be difficult to advise the use of DMSO in clinical treatment of mastitis until additional data is available.