Phylogenetic analysis of env gene of bovine leukemia virus strains spread in Miyazaki prefecture, Japan.

To understand how the latest dominant bovine leukemia virus (BLV) strains were introduced and spread in the Miyazaki prefecture, we collected blood samples from 3 geographic areas (north, central and south) and carried out sequence analysis of the BLV env gene. Two genotypes, genotype I, and III, were identified and the majority of the strains belonged to genotype I (71/74). To clarify a route of BLV introduction, we divided the strains into 20 subgenotypes based on their nucleotide sequences and performed phylogenetic analysis. Our study indicated that common BLV strains were comparatively evenly distributed even in the area, where the farmers have not introduced cattle from other areas and the cattle have limited exposure to BLV infection in grazing fields.

Comparative therapeutic effect of toltrazuril, sulphadimidine and amprolium on Eimeria bovis and Eimeria zuernii given at different times following infection in buffalo calves (Bubalus bubalis).

We compared the therapeutic effect of three anticoccidial drugs (toltrazuril, sulphadimidine and amprolium) in buffalo (Bubalus bubalis) calves experimentally infected with Eimeria bovis (E. bovis) and E. zuernii oocysts (3 x 104oocyst/calf). Buffalo calves (1.5-4 month old, 70-kg body weight) were randomly allocated into 3 groups (9 calves each). Group T was experimentally infected with oocysts and treated with toltrazuril (20 mg/kg BW twice orally at a 1-week interval). Group S was experimentally infected with oocysts and treated with sulphadimidine (125 mg/kg injected IM followed by half dose for 4 successive days). Group A was experimentally infected with oocysts and treated with amprolium (50 mg/kg orally for 7 successive days). Each group had three subgroups (three calves/subgroup) to represent timing of the drug administration: 1st day of coccidia infection (FD), onset of clinical signs of coccidiosis (CC), and onset of oocyst shedding into the faeces (OS). Clinical signs, body-weight gain (BWG) and number of oocysts per gram feces (OPG) were monitored daily for 35 days post-infection (DPI). The OPG were reduced (but the BWG was not different) in the T calves compared to S and A calves. Within the same group, treatment from the 1st day of infection reduced the OPG and increased the BWG compared to the later treatment timings.