13.—(1) This article applies to a breeding herd on the date that article 12 ceases to apply to the herd in accordance with article 12(2)(a).
(2) This article ceases to apply on the date falling 12 months after this article first applies.
(3) Where this article applies, the keeper must take—
(a)an ear tag sample of tissue taken in accordance with article 14, or
(b)a sample of blood,
from each calf born in the herd.