Which disease is specific to sheep and goats, and not considered a disease of cervids?

Scrapie is a progressive and fatal neurodegenerative condition that primarily affects sheep and goats, distinguishing it as a specific disease for these animals. It is classified as a transmissible spongiform encephalopathy (TSE), which is characterized by the accumulation of prions in the brain, leading to neurological symptoms and ultimately death.

Unlike Brucellosis, which can affect a range of livestock including cattle and cervids, or Chronic Wasting Disease, which is specific to cervids such as deer and elk, Scrapie does not occur in these other animal groups. Similarly, while Foot-and-Mouth Disease affects various livestock, including cattle, pigs, and sheep, it again is not exclusive to sheep and goats. Therefore, Scrapie is the only disease in this list that is unique to ovine (sheep) and caprine (goat) species, making it the correct answer for the question.