How much blood does a tick suck? - briefly
A tick typically ingests about 0.5–1 µL of blood per feeding, with the exact volume depending on species and developmental stage. Fully engorged adult females can reach roughly 1 µL in total.
How much blood does a tick suck? - in detail
Ticks ingest remarkably small quantities of blood, yet the volume varies significantly with species, life stage, and feeding duration.
Adult female Ixodes scapularis, a common black‑legged tick, can acquire up to 0.5 ml during a single engorgement lasting 5–7 days. In contrast, nymphs of the same species typically ingest 0.02–0.06 ml over 3–4 days, while larvae rarely exceed 0.001 ml in a 2‑day feed. Larger species such as Dermacentor variabilis (American dog tick) may reach 1 ml in adult females after 7–10 days of attachment.
The amount of blood taken is proportional to the tick’s body mass increase: an unfed adult female weighs about 2 mg and swells to 200 mg after feeding, indicating a 100‑fold mass gain derived from the host’s blood.
Factors influencing the volume include:
- Host skin thickness and immune response, which can limit attachment time.
- Ambient temperature; higher temperatures accelerate metabolic rate and shorten feeding periods, potentially reducing total intake.
- Tick’s reproductive status; gravid females prioritize blood intake for egg development, attaining maximum volumes.
Measurement techniques involve weighing ticks before and after feeding with a microbalance (accuracy ± 0.01 mg) and calculating the mass difference, assuming blood density ≈ 1 g/ml. Some studies employ hematocrit analysis of the tick’s gut contents to verify blood composition.
Understanding these quantities is essential for estimating pathogen transmission risk, as the probability of disease transfer correlates with the duration of attachment and the volume of blood ingested.