Chapter Bovine
Click on the FLASH Card & Scroll down for QUIZ
Q: What is Bovine Viral Diarrhea (BVD)?
A: Bovine Viral Diarrhea is a contagious viral disease in cattle caused by the Bovine Viral Diarrhea Virus (BVDV), leading to respiratory, gastrointestinal, and reproductive issues.
Q: What are the two main genotypes of Bovine Viral Diarrhea Virus (BVDV)?
A: The two main genotypes are BVDV-1 and BVDV-2, each with different strains that can vary in virulence and clinical impact.
Q: How is BVD transmitted among cattle?
A: BVD is transmitted through direct contact with infected animals, contaminated equipment, bodily fluids, and from mother to fetus during pregnancy.
Q: What are common clinical signs of BVD in cattle?
A: Clinical signs include diarrhea, fever, respiratory distress, nasal discharge, oral lesions, reproductive failure, and immunosuppression.
Q: What is mucosal disease in the context of BVD?
A: Mucosal disease is a fatal form of BVD that occurs in persistently infected (PI) animals when they are superinfected with a cytopathic strain of BVDV.
Q: What is a persistently infected (PI) animal in BVD?
A: A PI animal is one that was infected in utero with non-cytopathic BVDV before its immune system developed, causing it to carry and shed the virus for life.
Q: How is BVD diagnosed in cattle?
A: BVD is diagnosed through PCR testing, virus isolation, serology, or antigen-capture ELISA from blood, milk, or tissue samples.
Q: What are the reproductive impacts of BVD infection?
A: BVD can cause abortion, stillbirths, congenital defects, and birth of persistently infected (PI) calves when pregnant cows are infected.
Q: How can BVD be prevented in cattle herds?
A: Prevention includes vaccination, biosecurity measures, testing and culling of PI animals, and isolating new or returning cattle before introduction.
Q: Why is vaccination important in controlling BVD?
A: Vaccination helps protect cattle from BVD infection, reducing the likelihood of PI animals and minimizing reproductive and economic losses.
Q: What is the role of biosecurity in controlling BVD?
A: Biosecurity practices, such as isolating new cattle and controlling farm access, help prevent the introduction and spread of BVDV in a herd.
Q: How does BVD lead to immunosuppression in cattle?
A: BVDV impairs the immune system, making infected cattle more susceptible to secondary infections and diseases.
Q: What is the significance of identifying PI animals in a BVD control program?
A: Identifying and removing PI animals is crucial as they continuously shed the virus, posing a major source of infection for the herd.
Q: What are the economic impacts of BVD on cattle farms?
A: BVD causes losses due to reduced milk production, decreased growth rates, reproductive issues, increased veterinary costs, and culling of infected animals.
Q: Why is early pregnancy a critical period for BVD infection?
A: Infection during early pregnancy can lead to fetal infection, abortion, or the birth of PI calves, contributing to the persistence of BVD in the herd.