Control of the infection with Brucella melitensis in cattle

Abstract

Sera from1722 cattle of different age (3 months to 8 years) were examined by the Rose Bengal and tube agglutination test: 134 cow give positive result and the overal Brucella seroprevalence was (8%) milk samples zeropositive milking cattle were cultured on Brucella selecative media. Seropositive cattle (102) were treated for the first time with long acting oxytetracyclin at the dose of 20 mg/kg of body weight administered intramuscularly (i.m) every 2 days for 30 days and streptomycin at 25 mg/kg (i.m) every 2 days for 16 days. The regimen was found to be effective in eliminating the shedding of Brucella organisms by cattle in milk. Moreover all treated cattle became zeronegative within 16 months after treatment…zeronegative cattle (1588)were vaccinated for the first time with the Br.Melitensis as follows 1. 362 young cattle(aged three months to one year)were each inoculated subcutaneously with a full dose(1×106)viable organisms in 1 ml, Brucella antibody titers were detected 2-4 weeks post vaccination then decreased gradually until the animals became zeronegative 8 months after vaccination. 2. 1226cattle aged more than one year were each inoculated subcutaneously with reduced dose (1×103 viable organism in 1 ml)antibody titers measured 2-4 weeks post vaccination then decreased gradually until the animals became zeronegative 3 months post vaccination.No Brucella organisms were seen from repeated udeer secretion samples from all vaccinated milking cattle, and no abortions were recorded among pregnant vaccinated cattle.