gastric-lavage (Ambystomatidae)

Knowledge graph centered on gastric-lavage (Ambystomatidae) with 61 nodes and 198 connections. Top connected: Bombus, Ligusticum porteri, Asteraceae, Rushes, Erigeron.

Method synopsis

Modified gastric-lavage technique to obtain stomach contents for prey identification, enumeration, and biomass/caloric calculations using published conversion factors.

Synthesized from method descriptions across 6 papers using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — Foraging tactics in alternative heterochronic salamander morphs: trophic quality of ponds matters more than water permanency (2007), Freshwater Biology. Implementations in other papers (listed below) may differ.

1. Diet sampling
   Captured salamanders by dip-netting between 18 June and 18 July 2002 and identified by toe clip. Collected stomach contents using gut-flushing procedure by injecting current of water into salamander stomach through oesophagus. Prey items in suspension expelled through mouth and stored in separate vials containing ethanol.
   Quantities: Captured and analyzed stomach contents from salamanders across all 8 ponds during study periodDuration: One month sampling period: 18 June - 18 July 2002Conditions: Summer sampling during active foraging period
   Equipment: dip nets, gut-flushing equipment, ethanol storage vials
2. Prey identification and measurement
   Identified prey items and measured total length or head width depending on taxa under stereoscopic microscope. Each salamander was included in analysis only once. Grouped prey items into ten functional categories: Diptera larvae (DL), Diptera pupae (DP), Chaoborus larvae (CL), other Insecta larvae (IL), Hemipteroidea (HE), Hirudinae (HI), Microcrustaceans (MC), fairy shrimp (FS), other miscellaneous aquatic prey (MS) and terrestrial insects (TI).
   Quantities: 10 functional prey categories analyzedDuration: Not specifiedConditions: Laboratory analysis under stereoscopic microscope
   Equipment: stereoscopic microscope
3. Energy analysis
   Determined dry mass of stomach-flushed prey using relationships between biomass and length for each prey type previously obtained from invertebrates in Mexican Cut Nature Preserve. Calculated energy values of stomach contents using regression between dry mass and joules for each prey type. Used MANOVA to determine whether energy intake was similar across ponds and t-Tests to determine whether water permanence affected energy intake.

Typical Equipment

• gastric-lavage equipment
• dissecting microscope

Output Measurements

• prey taxonomic composition
• prey biomass
• caloric content

Papers Using This Protocol (6)

Species Studied With This Protocol