Which statement best defines IBR?

Which statement best defines IBR?

• A. Causes destruction of the cotyledons of the uterus.
• B. Sterile female calf born twin to a male calf.
• C. Condition in which one or both testicles remain in the body cavity.
• D. Viral disease of the respiratory tract that can cause abortion.

Answer: (D)

IBR is Infectious Bovine Rhinotracheitis, a herpesvirus infection in cattle that most often presents as a viral respiratory disease and can cause abortion in pregnant cows. The best statement captures this by describing it as a viral disease of the respiratory tract with the potential to cause abortion, which is a hallmark impact of the infection. The other descriptions point to conditions not caused by IBR: destruction of cotyledons relates to placental pathology, freemartin refers to a sterile female twin to a male, and cryptorchidism is an undescended testicle.

IBR is Infectious Bovine Rhinotracheitis, a herpesvirus infection in cattle that most often presents as a viral respiratory disease and can cause abortion in pregnant cows. The best statement captures this by describing it as a viral disease of the respiratory tract with the potential to cause abortion, which is a hallmark impact of the infection. The other descriptions point to conditions not caused by IBR: destruction of cotyledons relates to placental pathology, freemartin refers to a sterile female twin to a male, and cryptorchidism is an undescended testicle.