Objective—To evaluate the endocrine and immune responses of steers challenged with infectious bovine rhinotracheitis virus (IBRV).
Animals—12 crossbred beef steers.
Procedures—Steers were randomly assigned to IBRV– (control) or IBRV+ treatment groups. Experimentally challenged steers (IBRV+) received a dose of IBRV intranasally (8.0 50% tissue culture infective doses), IBRV– steers received a saline (0.9% NaCl) solution placebo intranasally, and each group was placed in an isolated paddock. At 72 hours after challenge, all steers were fitted with indwelling jugular catheters and placed into individual stanchions. Blood samples were collected on days 4 through 8. Serum was analyzed for concentrations of cortisol, interleukin-6, interferon-γ, tumor necrosis factor-α, growth hormone, and insulin-like growth factor I.
Results—From 72 to 144 hours after challenge inoculation, the IBRV+ group had significantly greater mean rectal temperature, compared with the IBRV– group; the greatest temperatures in both groups were observed at 72 hours. Serum cortisol concentrations were increased in both groups from hours 72 to 136 and serum interferon-γ concentrations were greater in the IBRV+ from 94 to 112 hours after inoculation. Growth hormone concentration was greater in the IBRV+ group at various time points, but no difference in insulin-like growth factor- I concentration was observed.
Conclusions and Clinical Relevance—Results indicated that IBVR challenge altered growth hormone concentration at some time points but was not associated with large increases in circulating proinflammatory cytokines.
Objective—To determine whether testicular needle
biopsy is detrimental to testicular function in clinically
Animals—6 mixed-breed mature bulls.
Procedure—A randomly selected testicle from each
bull was biopsied with a 14-gauge needle biopsy
instrument. Bulls were then evaluated over a 90-day
period for changes in scrotal temperature and thermal
patterns, ultrasonographic appearance, and quality of
spermatozoa. At the end of the 90-day study, bulls
were castrated, and testicles were examined grossly
Results—Changes were detected in scrotal temperatures
and thermal patterns and in the breeding soundness
examination results during the first 2 weeks of
the study. However, there were no long-term
changes in semen quality over the course of the
experiment. Hyperechoic areas were detected on
ultrasonographic examination and corresponded to
the areas of penetration by the biopsy instrument.
Microscopic lesions that were indicative of testicular
dysfunction were not found.
Conclusions and Clinical Relevance—Results indicate
that testicular biopsy is a safe procedure in bulls.
Testicular biopsy could possibly be used to further
examine bulls that have less than satisfactory results
for breeding soundness examinations. (J Am Vet Med