What function is lost due to demyelination of nerves in canine distemper?

Demyelination of nerves in canine distemper leads to the loss of saltatory conduction, which is crucial for the efficient transmission of electrical impulses along the axons of neurons. In healthy neurons that are myelinated, the myelin sheath acts as an insulating layer that allows electrical impulses to jump from one node of Ranvier to another, significantly speeding up the conduction velocity of the nerve impulses. This rapid transmission is vital for coordinated body movements and reflexes.

When demyelination occurs, this saltatory conduction is impaired. Instead of jumping along the myelinated segments, the impulses must travel continuously along the entire axon, which is much slower and less efficient. This can result in a variety of neurological symptoms and functional deficits in affected animals, as the timely and rapid communication between nerves is compromised. Hence, the correct answer highlights the critical function that is lost due to this demyelination process.