A Day in the Life of a Laboratory Beagle
Hour by hour through a 90-day subchronic toxicology study — from transport at six months old to terminal necropsy on Day 90. Every claim sourced from peer-reviewed literature, regulatory guidance, or published industry protocols.
The beagle is approximately six months old. It has spent its entire life in a breeding facility — likely Marshall BioResources or Envigo/Inotiv. It has been tattooed, microchipped, vaccinated, and possibly devocalized. Now it is loaded into a transport crate and driven — or flown — to a contract research organization where it will spend the next 90 days.
The physiological stress of transport is not speculative. Bergeron et al. (2002) measured a 67% rise in plasma cortisol in beagles during road transport. Herbel et al. (2020) found something worse: in transport-naive beagles — dogs experiencing vehicle transit for the first time — salivary cortisol increased eightfold. This was not a brief spike. Cortisol remained elevated for the duration of transit and did not return to baseline until well after arrival.
Critically, repeated transport does not produce habituation. Dogs transported multiple times showed no reduction in cortisol response. The stress is not something they “get used to.” Sedation does not help either — Bergeron found that acepromazine, the most commonly used transport sedative, “did not significantly affect any measured variable.” The dogs were chemically quieted but physiologically just as stressed.
Behavioral observations during transit show dogs spending more than 50% of travel time lying down and 75% inactive overall. This is not calm — it is behavioral shutdown. Lip licking, one of the most frequently observed behaviors, has been shown to have a nausea component beyond pure stress, suggesting motion sickness compounds the psychological distress.