What causes curled toe paralysis in chicks, and what are the mating terms for (A) sheep, (B) ducks, (C) cattle, and (D) pigs?

The first question is incomplete as the full question text is not visible, only the options A, B, C, D which are "tupping", "treading", "servicing", and "coupling". These terms generally refer to the act of mating in various animals. Without the specific animal or context, I cannot provide an answer.

For the second question:

Curled toe paralysis in chicks is caused by the deficiency of riboflavin (Vitamin B2).