Combined treatment with a dithiosemicarbazone and oxytetracycline to eliminate Anaplasma marginale infections in splenectomized calves.

A total of iz treatmct schcdules consbiing oxytetracycline and an alpha­ dithiosetnicarbazonew'ere tested in' 36 splcnectomizcd calves carrying Anaplasma marginale infections. Anaplasma itifrtion was elimiatcdfollo'in[g the administration of 5 or ionig./kg. dithiosemicarbazone combined with j img./lkq. oxytetracycline, and gi,en 3 times at 24 or 48 hr. intervals. Treatments employing ho'er drg"lcels, feuwer injections, or at greater tie intervals failed to eliminate infection. Treatd splenctomizcd cales failin, to show evidence of an A. marginalc relapsing infection within 62 days w'refound to be free of infection on the basis of infectivity trials conducted an average of 87 days after treatI1ent, and by re-inoculation n'ith A. marignale an av'erage of 164 days after treatment.