Resistance of colostrum-deprived domestic lambs to infection with deer adenovirus.

Seven colostrum-deprived, 3-4-wk-old Rambouillet-Hampshire lambs were inoculated via the mucous membranes with deer adenovirus (DAdV) and monitored for clinical signs for 21 d post-inoculation at which time animals were euthanized and postmortem examinations were performed. Pre-inoculation and post-inoculation serum samples were tested for antibodies to DAdV, ovine adenovirus 7, bovine adenovirus 7, and goat adenovirus 1. Evidence for DAdV infection was determined by virus isolation, PCR tests, and histopathology with immunohistochemistry tests for DAdV. No clinical signs or lesions consistent with adenoviral hemorrhagic disease (AHD) in deer were seen in the lambs, and the lambs did not seroconvert to DAdV. DAdV was not detected by PCR, virus isolation, or immunohistochemistry in any of the samples tested from the lambs. A positive control deer similarly inoculated with DAdV developed fatal AHD 1 wk post-inoculation. Our colostrum-deprived lambs did not become infected when inoculated with DAdV.

Evaluation of the pathogenic potential of cervid adenovirus in calves.

Four 3-month-old Jersey calves and three 3-month-old Holstein calves were inoculated with cervid adenovirus and monitored for clinical signs until necropsied between 10 and 42 days postinoculation. The neonatal Jersey calves had received colostrum, and the Holstein calves were colostrum deprived. Preinoculation and postinoculation serum samples were tested for antibodies to the cervid adenovirus, bovine adenovirus type 6, bovine adenovirus type 7, and goat adenovirus type 1. Virus isolation was performed on kidney, nasal secretion, and/or lung homogenates in fetal white-tailed deer lung cells. Negatively stained preparations of feces from Jersey calves were examined weekly using an electron microscope, and weekly blood samples were collected for complete blood counts. Full necropsies were performed on all calves. A complete selection of tissues was evaluated for microscopic changes, and immunohistochemistry was performed on all tissues using a polyclonal antibody to deer adenovirus. No clinical signs were observed in the calves during the study period. Following inoculation, colostrum-deprived calves developed low antibody titers to deer adenovirus, while the Jersey calves that received colostrum did not. Calves that received colostrum had high antibody titers to bovine adenovirus type 7 and goat adenovirus type 1. No consistent gross or microscopic lesions were seen. Adenovirus was not observed in negatively stained preparations of feces. Immunohistochemistry results did not demonstrate virus in all tissues examined microscopically, and virus was not isolated from lungs, nasal secretions, and kidneys.