Livestock animals may be affected by infectious diseases caused by parasites such as tsetse flies, ticks, mosquitoes, and Culicoides midges, or by microorganisms such as viruses, fungi and bacteria. Some of the examples of infectious diseases in animals include bovine virus diarrhea (BVD), tuberculosis, Johne's disease, and brucellosis. Infectious diseases in animals are caused due to factors such as the addition of new member to a herd and contaminated water. The assessment or diagnosis of livestock diseases is essential for detecting the cause and nature of the disease, which, in turn is essential for ensuring faster treatment planning. Livestock diseases are diagnosed using techniques such as analysis of blood, tissue, urine, or stool to detect the presence of proteins, antibodies, or general indicators of overall health. The first step in the treatment of the infected livestock animals usually involves isolating the affected animal from the rest of the herd. Additionally, the infected animals are also given anti-inflammatory drugs and antibiotics. This book unravels the recent studies on the diagnosis and treatment of diseases in livestock. It is appropriate for students seeking detailed information in this area of veterinary science as well as for experts.