Continued functioning of the feeding apparatus during moulting of Boophilus microplus as an adaptation of one-host ticks.

Abstract

Nymphs of the 1-host cattle tick Boophilus microplus remain attached to the host during moulting, but this process is not uniform throughout the tick tissues. The muscles of the pharynx and salivarium remain attached to the cuticle and are functional while the cuticle of the legs has already separated from the underlying epidermis and muscle. The nymphs continue to feed for 2 days after the moulting process in the legs has begun, and they more than double their weight in this time. Mouth-part primordia of the adults develop while the nymphs are still feeding. These adaptations could be an advantage of a 1-host feeding strategy, as they decrease the non-feeding development time spent on the host. In the 3-host tick Haemaphysalis longicornis, which moults off the host, the pharynx, salivarium and legs all begin the moulting process at the same time.