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Developmental Cycle

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Egg

After mating and the completion of the blood meal, female ticks seek sheltered environments, similar to those used by the immatures for molting, to lay their eggs.

The period between engorgement and the commencement of oviposition ist the pre-oviposition period; it's length varies, depending upon the species, temperature, diapause and, possibly, other factors.

Maximum egg yields normally are produced only by females that have mated and engorged to repletion.

The number of eggs produced by mated, blood-fed ticks is dependent upon many factors, the most important of which are:

  • blood meal volume
  • egg size
  • species

Blood meal volume is the major determinant affecting the number of eggs deposited. In general, females consuming larger blood meals lay more eggs. In the Argasidae, small egg batches are deposited after each blood meal. These ticks are capable of feeding and ovipositing many times, i.e., they have multiple gonotrophic cycles. In Argas persicus, batches contained from 47 to 646 eggs. In the Ixodidae, the mated females lay thousands of eggs in a single gonotrophic cycle. Ixodid ticks exhibit phenomenal fecundity, perhaps the highest of any hematophagous arthropod. In Dermacentor variabilis, a typical example, oviposition begins within 3-6 days after females feeding. Egg production surges rapidly, reaching a peak on the 4th day, and continuing for an additional 16-17 days, for a total of 20-21 day egg laying period. The American Dog tick lays an average of 5.380 eggs/female (Sonenshine and Tignor, 1969). The largest egg mass ever recorded for a single tick was 22.891, from a single Amblyomma nuttalli female.

   

Further information

  • Sonenshine DE: Biology of Ticks. Part 1, 1991, Oxford University Press, New York
  • Sonenshine DE, Tignor JA: Oviposition and hatching in 2 species of ticks in relation to saturation deficit (Acarina: Ixodidae). Ann Entomol Soc Am. 1969, 62, 628-40

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