Beagles and Toxicology

Why beagles?

There is no scientifically valid justification why the beagle is the pedigree used in animal testing, just as there is no scientific reason to use dogs or any other animals.

These are the main reasons why the beagle is the preferred dog breed in animal experiments:

• Docile temperament
  Commonly, when beagles feel fear, are in pain, or are under attack, they will freeze rather than fight back. This makes it easier for technicians to subject these dogs to experimental procedures and reduces the risk of being bitten.
• Size and physical traits
  Their medium size makes them easier to house and transport, and their short coats are easy to maintain and allow easy access for skin testing procedures.
• Historical precedent
  Beagles have been used in toxicology testing for decades. Project licences often justify the use of beagles in experiments by referring to the large amount of existing data on beagle biological responses. However, they fail to acknowledge that this data is largely irrelevant to human biology.
• Regulatory conformity
  The UK and other countries choose to conform to international guidance requiring drug safety to be tested on two mammalian species — one rodent and one non-rodent — before human trials. During the 1940s and 1950s, the use of beagles in toxicology and pharmaceutical testing became systematised, and this pedigree dog became the standard non-rodent species used by laboratories.

The beagles at MBR Acres

The beagles inside MBR Acres undergo training literally from the day they are born. Staff working at MBR submit the puppies to accept handling, and train them to comply with the intrusive procedures they will endure when they are sent to toxicology laboratories:

• The puppies are trained to submit their necks and front legs to have blood samples taken.
• They are hung from slings from a very early age.
• Gas mask are placed over their muzzles to train them for inhalation tests
• They are taught to open their mouths on demand for gavage procedures
• They are exposed to hair clippers to be used in skin irritation tests

In addition to the training, puppies are regularly graded against sale standards and put through a behaviour evaluation to mark their temperament as good or bad.

The puppies that ‘fail’ their training, grading assessment or behaviour evaluation will be KILLED on site by their veterinary.

How many beagles?

According to UK statistic, since Camp Beagle started circa of 2500 beagles have been used every year, except 2024 that saw a significant decrease of 33%, with 1,593 dogs used in experimentation.

Note these figures do not include the number of puppies bred but never used in any experiment because they failed to meet the sale standards.

The number of beagles used worldwide is not known but it is estimated to be circa 100,000 every single year.

Toxicology

The overwhelming majority of the beagles bred at MBR Acres are sold to contract toxicology laboratories to undergo regulatory procedures. Toxicology tests evaluate the harmful effects of chemical products and pharmaceutical drugs by administering the test compound on live animals at varying doses and observing its impact on the health, behaviour, organ function, or reproductive capacity.

However, evidence consistently shows that results obtained from animals testing do not translate to human biology reliably and provide data that is of no relevance to human health. As a consequence, over 90% of drugs that appear safe and effective in animal studies fail during human clinical trials, either because they prove to be toxic to humans or because they lack efficacy.

Below is a general description of the toxicology testing procedures that beagles are subjected to:

1. Group allocation

Dogs are randomly divided into groups, typically:

• Control group (receives a placebo dose)
• Low-dose group
• Mid-dose group
• High-dose group

Group size is often 32 to 40 dogs, depending on the study, plus about 4 dogs left on ‘reserve’.

Dogs are kept in cages inside the lab, most commonly one per cage, rarely two per cage.

2. Dose administration

The test substance is administered via a relevant route (e.g. oral, dermal, inhalation, ocular, injection, etc.). Doses increase stepwise across groups to identify:

• No-Observed-Adverse-Effect Level (NOAEL)
• Lowest-Observed-Adverse-Effect Level (LOAEL)
• Maximum tolerated dose (MTD)

3. Study duration

Typical ranges:

• Acute toxicity: Single dose, observation for 14 days
• Sub-acute: Repeated dosing for 14–28 days
• Sub-chronic: Repeated dosing for approximately 90 days
• Chronic toxicity: 6 months to 2 years
• Reproductive/developmental studies: Across mating, pregnancy, and offspring development

4. Observations and measurements

– Daily monitoring for:

• Behavioural changes
• Clinical signs of toxicity
• Morbidity or mortality

– Periodic measurements:

• Body weight, food and water intake
• Blood and urine analysis
• Functional tests may be included such as neurological, respiratory, or cardiovascular assessments

5. Study termination and analysis

At the end of the study, in most cases, the dogs are killed to perform necropsy analysis.

Organs are weighed and examined for histopathology and cellular damage.

Occasionally, at the end of some studies, the dogs are not killed. Those dogs are then re-used in other studies.

6. Data interpretation

Results are analysed to understand how dogs responded to the different doses and to determine toxicity levels in dogs.

However, this data is irrelevant to human health and it only serves as a regulatory tick box exercise.

Extract from Charles Rivers website.

https://www.youtube.com/watch?v=MjqpwPYSZsM

Undercover investigation in a Canadian laboratory, depicting the reality of toxicology procedures on beagles.