Distressed and bewildered following brain damage, Virgo has a fresh head wound that is wet and bleeding. As she cries out and tries to escape from the confines of the incubator, fresh blood is splattered across the plastic sides.

"Fitting, awake & bewildered"
"Head red, raw and bleeding"
Researcher describing condition of monkeys following brain damage

Suffering

After surgery, the monkeys were given a pain relief injection and then placed in a recovery cage or incubator. The immediate post-operative effects suffered by the monkeys could be severe and included pain, distress, bleeding from head wounds, fits, vomiting, tremors, swelling and bruising, loss in body temperature, failure to eat and drink, abnormal body movements such as twisting of the head and rotation of the whole body, loss of use of one arm or whole side of body, loss of balance or visual disturbances.

The researchers' own words provide a chilling insight into the distress and suffering experienced by the marmosets:

• "Head red, raw & bleeding"
• "Twitching limbs, shaking"
• "Fitting, awake & bewildered"
• "Awake, moving around & crying"
• "Moving in circles"

Some monkeys needed to be kept in the incubator for a number of days being hand fed. Others died or had to be killed because of the level of suffering:

• "Died... graft monkey - developed swelling on throat"
• "three days post surgery he suddenly collapsed in home cage, sitting with head down"
• "Found collapsed & soon died"
• "Found fitting in home cage, put down after failure to regain consciousness"

Long-term effects included physical disabilities, learning and memory impairment, weight loss and lack of self-care. However, no one can ever know the true cost to the monkeys' mental and emotional well being such as confusion, frustration, anxiety, fear and mood alterations.

For the BUAV investigator, one of the most heartbreaking things was to see the difference in the monkeys before and after brain damage, particularly those she had got to know well as individuals. Many seemed confused with blank expressions on their faces; their bodies uncoordinated. One monkey's pitifully confused state was described by a researcher as "watching the birdies".

Following surgery, many monkeys were often subjected to a battery of tests, assessments, injections and blood sampling. This undoubtedly caused additional suffering and distress:

• "Throat bled as struggled"
• "Bleeding into thigh"
• "Extensive seepage of blood in left leg"

Finally, however, all the experimental monkeys would be killed and their tiny bodies dissected. They were killed by injection and their brains were cut out and placed in jars for future examination. Their bodies were stored in a freezer before being disposed of like laboratory waste.

The only lasting indication that these once beautiful, intelligent and intriguing animals ever existed at all as individual characters was the name label stuck to the jar holding their brain.

See for yourself some of the actual secret footage as filmed by our investigator.

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