Blood Meal
Definition
Blood ingested by a haematophagous insect during feeding on a vertebrate host. The host's DNA persists in the insect's gut for hours to days and can be extracted and profiled to identify the species or individual that was bitten.
- Definition
- Blood ingested by a haematophagous insect while feeding
- Host DNA persistence
- Hours to days within the insect gut
- Forensic use
- Species or individual identification of the fed-upon host
- Relevant insect groups
- Mosquitoes, bed bugs, and other blood-feeding arthropods
Common questions
How is host DNA recovered from a blood meal for identification?+
The insect's abdomen or gut is dissected and the blood meal content is extracted using standard DNA extraction methods, then amplified with PCR targeting either species-diagnostic mitochondrial markers or human-specific STR loci, depending on whether the goal is species or individual identification.
Why does the age of the blood meal limit what can be recovered from it?+
Digestive enzymes progressively degrade the ingested blood, so DNA quality and quantity decline the longer the meal has been in the insect's gut. Analysts generally have a window of a few hours to a few days post-feeding before degradation makes reliable profiling difficult or impossible.
Related terms
- COI Barcoding
- DNA-based species identification using a standard 658 bp segment of the mitochondrial cytochrome oxidase subunit I gene. Sequences are matched against reference...
- Gut Content Extraction
- Physical dissection of a larva to remove the crop and midgut contents, which are then extracted separately from the larval carcass. The...
- Haematophagous Insect
- An insect that feeds on the blood of a vertebrate host. Examples include mosquitoes (Culicidae), sand flies (Phlebotomus, Lutzomyia), and certain midges...
- Mitochondrial DNA (mtDNA) Haplotype
- A characteristic sequence of the mitochondrial genome used to assign an individual to a maternal lineage. More copies per cell than nuclear...
- Mixed-Source Profile
- A DNA profile resulting from a mixture of two or more contributors. Gut content extractions routinely produce mixtures of insect DNA and...