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Objective: To evaluate clearance, antibody responses, potential shedding, and histologic lesions in reproductive tissues of adult bison bulls after vaccination with Brucella abortus strain RB51., Animals: 61 two- and 3-year-old bison bulls., Procedure: 12 bison bulls were vaccinated s.c. with B abortus strain RB51, 3 were inoculated s.c. with 0.15 M NaCl, and antibody responses were evaluated. Various specimens were obtained to evaluate bacterial shedding. Four vaccinates and 1 control were necropsied 10, 20, and 30 weeks after vaccination. In a separate experiment, bison bulls were vaccinated s.c. with 0.15 M NaCl, or by hand or ballistically with strain RB51. Antibody responses were monitored 6 weeks after vaccination and during necropsy 13 weeks after vaccination. Tissue specimens obtained during necropsy from both studies were evaluated bacteriologically and histologically., Results: Strain RB51 was recovered at various times from semen of 3 of 12 vaccinated bison bulls in experiment 1. During necropsy, strain RB51 was recovered 10 and 20, but not 30, weeks after vaccination. In experiment 2, strain RB51 was recovered from lymphoid tissues of hand- and ballistic-vaccinated bison bulls during necropsy. In both experiments, microscopic lesions in testes, epididymis, and seminal vesicles were minimal and did not differ between strain RB51-vaccinated and saline-inoculated bison bulls., Conclusions and Clinical Relevance: Strain RB51 does not induce relevant inflammatory lesions in reproductive tissues of adult bison bulls. Shedding of strain RB51 in semen may be transient in some bison bulls; however, the importance of this observation is unknown.

The putative binding of porcine parvovirus (PPV) to semen components in vitro was examined along with the shedding pattern of PPV in oronasally infected boars. Porcine parvovirus DNA was determined to be bound to spermatozoa that had been incubated in vitro with PPV and washed to remove loosely adherent virus. To determine whether PPV was shed in the semen, four 8-month-old boars, seronegative for PPV, were inoculated oronasally with a virulent strain of PPV. Prior to virus inoculation, a catheter was surgically implanted in the vas deferens for the purpose of collecting cauda epididymal semen free of extrinsic contamination. Epididymal semen specimens were collected prior to inoculation and daily thereafter for 21 days. A fifth boar was inoculated oronasally with PPV, but semen was collected by electroejaculation twice weekly for an equal period of time. Reproductive glands and semen specimens from all boars were examined by nucleic acid hybridization for the presence of viral DNA. All boars seroconverted to PPV, as evidenced by serum antibody titers ranging from 512 to 8,192 hemagglutinating inhibition units/50 microliters. Porcine parvovirus DNA was detected in epididymal semen of 3 of 4 catheterized boars on postinoculation days 5 through 9, but not in semen obtained by electroejaculation. Viral DNA was consistently detected in tissue samples collected on postinoculation days 8 and 21 from the scrotal lymph nodes (4 of 5 boars) and epididymides (3 of 5 boars).

Infection with Brucella ovis was established by conjunctival instillation in 8 male white-tailed deer (Odocoileus virginianus). Infection was transient in young bucks, but persisted in bucks that were mature when inoculated. The deer were euthanatized and necropsied at various intervals after inoculation. Brucella ovis was recovered from a mature buck at necropsy on postinoculation day 429. Four deer had gross lesions and histopathologic changes of the epididymides. A mature noninfected buck confined for 7 months with an infected buck acquired infection and developed epididymal lesions.