Efficacy of various treatment regimens, using liposomal streptomycin in cows with brucellosis.
Thirty cows naturally infected with Brucella abortus were treated by various routes, using free or liposomal streptomycin or a combination of liposomal streptomycin and a long-acting oxytetracycline preparation. Of 21 cows treated with liposomal streptomycin alone, 3 (14%) were culture negative and 3 had 10 or fewer bacterial colonies isolated from tissues obtained at necropsy. Thirteen (62%) cows continued to shed organisms in udder secretions and were considered treatment failures. Of 9 cows that were given a combination of liposomal streptomycin and long-acting oxytetracycline, 5 (56%) were cured, 3 had 10 or fewer colonies on culture plates of tissue after necropsy and only 1 continued to shed B abortus in udder secretions after treatment. Eleven cows were given streptomycin liposomes by intramammary infusion with or without IM administration of long-acting oxytetracycline. The most effective regimen consisted of 2 intramammary infusions of streptomycin liposomes and 2 doses of oxytetracycline administered IM. Of 5 cows treated thusly, 2 were cured and all others had fewer than 10 B abortus colonies isolated from tissues obtained at necropsy.
Nicoletti
P
P
Department of Infectious Diseases, College of Veterinary Medicine, University of Florida, Gainesville 32610.
Lenk
R P
RP
Popescu
M C
MC
Swenson
C E
CE
D000818:Animals; D002003:Brucella abortus / Q000187:drug effects; D002007:Brucellosis, Bovine / Q000188:drug therapy* / Q000378:metabolism / Q000382:microbiology; D002417:Cattle; D004337:Drug Carriers; D004359:Drug Therapy, Combination / Q000008:administration & dosage / Q000627:therapeutic use; D005260:Female; D008081:Liposomes; D008321:Mammary Glands, Animal / Q000378:metabolism / Q000382:microbiology; D010118:Oxytetracycline / Q000008:administration & dosage / Q000627:therapeutic use; D013307:Streptomycin / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use
D004337:Drug Carriers; D008081:Liposomes; D010118:Oxytetracycline; D013307:Streptomycin