動物実験廃止・全国ネットワーク   JAPANEASE

about us

Let's stop
the violence
against and
exploitation of
life !


Too Many Monkeys Have Been Dying from Causes Other Than Animal Testing

A Report on “Causes of Deaths besides Experiments  Eat Primate Research Institute, Kyoto University

(June 2004)

Primate Research Institute at Kyoto University (Inuyama city, Aichi prefecture), which is well known for a chimpanzee named Ai, has been breeding a large number of primates and using them for experiments. Ava-net requested the laboratory to disclose its report on “experimental use, deaths due to experiments, and deaths from causes other than experiments Efor the year of 2003.

These three reports are submitted by marking ◁E but the “deaths from causes other than experiments Eis a written report on deaths resulted from accident and illness. According to the reports, there are various problems concerning the breeding and experimental use of primates.

We would like to show what is really happening behind the scenes of animal testing. Although some parts are omitted, details on death and autopsy findings are reprinted as is.

(*[ ] are writer’s notes. Ages of monkeys were calculated from birth and death dates. In addition, indicates portions of the report which had been marked out.)

Death by accident: unable to pull the arm out

Rhesus monkey (female, 5 months old)
She seems to have died from not being able to pull out her right arm, which was caught between spaces of the perch that were 13 ? 16ft high.

Death by accident: accidental hanging

Rhesus monkey (male, 4 months old)
Found hanged with rope around his neck on the morning of 11/7/03. As I entered the facility in an attempt to recover him, the mother took him and run away. With ’s help, we ran after and recovered him. [...] Although he appears to have died from hanging, pneumonia was also found. Accidental death.

Death by accident: Died from blood loss resulting from tranquilizing gunshot

Japanese macaque (male, 9 years and 4 months old)
Transferred from playground #3 to #4 on 11/13/03. External wound was found on lower left thigh on 11/14. On 11/17, he was captured with a tranquilizer gun and treated. He was found dead inside the cage on 11/18. 1) Hiatus and bleeding of the right abdominal wall and pyloric portion of the stomach. 2) Retention of pleural effusion, and pulmonary hemorrhage. 3) Softening of parenchymatous organ. Died from blood loss resulting from tranquilizing gunshot. [*1]

Death caused by external wound

Rhesus monkey (male, 10 years and 7 months old)
On 3/23, we captured him when he was moving inside the facility unsteadily. Numerous subcutaneous and muscular wounds were found all over the body. Many of those wounds were not fresh. Died during treatment. Traumatic shock seems to be the cause of death.

Examples where experimental failures can be learned

Rhesus monkey (male, 14 years and 2 months old)
Research purpose: To establish a model of “pancreatic islet autografting  Eas preliminary step to clinical application. Administered glucose tolerance tests on 5/29/02 and 6/24/03. On 6/26/03, caudal corpus pancreatis (as well as spleen) was removed, and pancreatic islet was separated from it. On the 5th day after the operation (7/1), we made him diabetic by administering medication. Succeeded in grafting separated pancreatic islet on 7/4. [...] He had a good appetite and no significant changes were seen; however, he was found dead on the morning of 9/14. Although he seemed to be improving gradually according to the glucose tolerance test, diabetic state continued and he also began to lose weight. Cause of death likely to be diabetic ketoacidosis. Gas from decomposition filled interperitoneal and the organs were necrotized.

Rhesus monkey (male, 13 years old)
Research purpose: Same as above [...] On the 5th day after the operation, we administered medication to make him diabetic. He was found dead inside the cage later in the evening. Appeared to be a bit listless after excision of caudal corpus pancreatic. Though IV was given to alleviate the drug toxicity, he died when for a brief period no one kept an eye on him. Rhemorrhagic ascites was detected. Believed to have died from peritonitis (due to pancreatic juice) and drug toxicity.

Death caused by delivery

Crab-eating macaque (female, age unknown, 14 years and 7 months after arrival)
Research purpose: Growth, development, and aging. Mated by Timed Mating method (without medication). Though she was in the last phase of pregnancy, edema and anorexia appeared few days ago. Dr. Goto treated her but she was found dead on the morning of 2/11. [...] Died from dystocia.

Stress from construction?

White Gibbon (female, 28 years and 11 months old)
She has been lying down on the floor and leaning against the wall since the morning of 6/3. Anesthetized in the evening, treated, and lost consciousness at night. Died before dawn despite the treatment. [...] Likely to have died of emaciation (lost appetite due to construction?).

So-called "Swollen-Belly" E

Rhesus monkey (male, 4 years and 3 months old)
Research purpose: To elucidate brain mechanism of high-order visual function. Made him feel comfortable in a monkey chair, and trained him to control the lever while looking at the visual stimulation shown on the computer display. Diagnosed as so-called “Swollen-belly Sickness. E found him dead on 8/19. No major signs of trouble until the day before. A number of subcutaneous bleeding over femur and lower extremity. [...] Considerable retention of digested solid sludge due to gastric intumescentia. Bubbles in portion of submucosa. Submucosal bleeding in an area of colon 6-18 cm from anus. Possible cause of death: an acute gastric flatulent.

Japanese macaque (female, 4 years and 5 months old)
Morning of 11/19 - A report was made concerning her slow movement and large abdomen. Captured in the afternoon and treated for gastric fratulent. Passed away before awakening from anesthesia. [...] Died of deglutition pneumonia. (At one point, peritonitis due to perforation of the colon was present.)

Rhesus monkey (male, 5 years and 10 months old)
Research purpose: To study cingulate gyrus cells which respond to clues that stimulate reward and aversion. [...] After training coursework, we recorded and analyzed activities of anterior cingulate gyrus and neurocyte. Found dead in the morning. No major signs of trouble until the day before. Provided solid food at 5 pm on the day before (). Foam from the mouth was found on the floor. No stool. Gastric intumescentia. Retention of digested solid matter in large quantity. [...] Possible cause of death: an acute gastric flatulent.

Crab-eating macaque (male, age unknown, 14 years and 8 months after arrival)
2/19 - weakened and died despite the treatment. (1) Bleeding of gastric mucosa, damaged gastric wall (2) gastric rupture (3) mucosal bleeding of small intestine (4) pulmonary hemorrhage. Died of acute gastrectasis and gastric rupture. [*2]

Other Illness

Crab-eating macaque (male, age unknown, 14 years and 9 months after arrival)
Research purpose: development and aging of primates. Unused (he was raised for mating but no longer used for that purpose). 3/17 (Wed) - loss of appetite, pale face; 3/18 (Thurs) - recumbent, loss of appetite -> hospitalized, X-ray (presence of shadow behind the liver); 3/19 (Fri) ? laparotomy (splenomegaly, anemia); 3/20 (Sat) Confirmed dead at 8:00. Died from: 1. splenomegaly 2. hematostasis, bacteremia (septicemia).

Japanese macaque (female, 28 years and 2 months old)
Research purpose: Study on cognitive function of elderly monkey. Learning and memory behavioral experiment using WGTA. Hospitalized from 5/30. Under treatment. Died on 6/3. Pulmonary hemorrhage, hematostasis, cyst on spleen. [*3]

Rhesus monkey (female, 21 years and 10 months old)
She has been hospitalized for two years without treatment. Died on 2/16. (1) Died from rupture of liver cyst. Bleeding of liver. Peritonitis. (2) Bleeding from small intestine to cecum.

Rhesus monkey (female, 11 years and 9 months old)
3/31 - Weakened, internment, and died despite of the treatment. Thoracic and pulmonary abscess.

Japanese macaque (female, 2 years and 3 months old)
Taken into an individual cage after a part-time worker found her lying down. Leaning against the wall, she was making a crowing sound as she breathed. She collapsed all of a sudden and vomited a large amount of water. Head appeared to be convulsing, but it gradually went away and pupils began to dilate. Her breathing as well as heart stopped. [...] Causes of death: (1) intestinal obstruction due to volvulus (2) pneumonia.

Rhesus monkey (female, age unknown)
Found her dead body at 10am. Died from mucosal bleeding of colon, trichuriasis, hemorrhage of gastric mucosa, eye ball retraction, and hemorrhagic enteritis.

Japanese macaque (female, 29 years and 4 months old)
Found dead in the morning (Mr./Ms. ). All dry food left, but she ate the apple which was provided by Mr./Ms. . Large amount of sludged vomit on the floor. Rabbits Estool. [...] Some sort of an infection suspected.

Japanese macaque (male, 3 years and 4 months old)
10/10 (Fri)- Transferred from playground #1 to #10 when he was found listless. Died in the morning of 10/12 (Sun). [...] Had five small hairballs inside the stomach. Cause of death: peritonitis due to perforation of endogastric hairballs.

Japanese macaque (female, 7 years old)
4/22 Though she ate an apple in a second, she did not touch other food at all. Found lying face down. Found dead on 4/23. Retention of large amount of brown-colored ascites. Presence of three hairballs inside the stomach, one in duodenum, and one perforation (2 Ex 0.6  E at 2 Efrom pylorus. Mucous membrane surrounding the perforation had fallen. A bit of fibrous adhesion on upper and left lobes. Right lung showed uneven colors of pink, red, and dark-red. Cause of death likely to be peritonitis which resulted from duodenal perforation.

Death of Young Individuals - emaciation, illness, external wound, bandonment, etc.

Japanese macaque (sex unknown, 15 days old)
In the morning of 8/17, 1131 (not biological mother of 1584) was holding the dead body. Recovered the body the next day. Details unavailable.

Cotton-top Tamarin (male, 2 months old)
Although this one of the twins looked to be in good shape with fine coat, he was almost hairless except for the head. Since he always looked hungry, banana with milk were often replenished. Mother carried him on her back until the night of 8th; however, in the morning of 9th, she let go of him as he weakened. Top 1cm of the tail was dark red-colored and necrotized. Slight subcutaneous bleeding at right upper elbow. A great volume of urine inside the bladder. No gastric contents. Digested banana and milk inside the intestine. No changes in lungs, heart, liver, spleen, pus, and kidneys. Cause of death: emaciation due to malnutrition.

Japanese macaque (female, 1 day old)
Research purpose: Comparative biochemistry of primates. Collected organs from the dead body. She seemed fine when we separated her from a group of young mother monkeys. At about two o’clock, she was kept warm with a towel. Became listless and died around four o’clock. Detected bleeding inside the brain and internal organ.

Common marmoset (female, 4 days old)
In the morning of 9/16, she was on the net alone. Later she was found by her mother. She also stayed beside her mother in the morning of 9/17; however, by 11 am she was found on the net abandoned by her mother. Had difficulty breathing. Taken into incubator, but died at 2 pm. Abdominal distention. No external wound. Vomit adhered around mouth. A large amount of milk inside the stomach. [...] Cause of death: likely to be pneumonia.

Common marmoset (male, 1 day old)
She was found calm on the net. Kept her warm while waiting for the mother to show up and hold the baby. She died the next day. No external wounds or abnormal tongue. No gastric contents. No particular problems in lungs, liver, or spleen. Causes of death: emaciation and abandonment.

Common marmoset (male, 0 day after birth)
A part-timer found him lying down inside the cage. Pneumatic lungs. No changes in internal organs. Intracranial hemorrhage, depression in part of skull, and subcutaneous bleeding of the skull. Died from external wound.

Hamadryad (male, 0 day after birth)
The mother was holding the baby with both hands when we went to the cage. His limbs were feeble and he was hanging down from the mother. Two lacerations (1 cm in diameter) which extended into muscular layer were present in thoracic region. Subcutaneous and intramuscular bleeding at the chest and back. Broken 3rd and 4th ribs. Intrathoracic bleeding. Clotted milk inside the stomach. Crushed cranium and cerebral fusion. Cause of death was thoracic external wound. Cervical fracture occurred posthumously.

Rhesus monkey (female, 5 days old)
Mother (Mm1465) was holding the baby upside-down. Limbs were feeble and she seemed to be dead already. We chased them, made the mother drop her, and recovered the body. No changes in thoracic and abdominal cavities. No gastric contents. No birth defects. Extensive subcutaneous bleeding was found at head and cervical regions. Presence of slight foul odor. Retention of a small quantity of intracranial blood. One bleeding focus in lobes. Depressions in frontal lobe. Died from cranium fracture and cerebral contusion. [*4]

Miscarriage, stillbirth, or eaten away

Common marmoset (sex unknown, miscarriage or stillbirth)
Did not conduct autopsy (could not find the corpse which had been preserved, it dried afterwards).

Rhesus monkey (sex unknown)
Did the birth happen few days ago? Appeared a little melted at the time of discovery. Autopsy was not allowed. Miscarriage or stillbirth.

Common marmoset (sex unknown, stillbirth)
Had been eaten away except for the head.

Cotton-top Tamarin (sex unknown)
Recovered when he was found down on the floor. Defective lower jaw, right arm, and lower limbs. Also appeared to have been bitten and torn. [Omitted hereinafter]

Hamadryad (male)
Around 11 o’clock, we found the mother (Ph.79) holding the corpse inside the cage. Recovered the body and conducted an autopsy. Pulmonary atelectasis. Miscarriage. [*5]

Common marmoset (one male and two unknowns, stillbirth)
c.j. [Note: Common marmoset] ? 39♀ had considerable bleeding three days before having a stillbirth baby. One had a head left, and the other had been eaten away completely. [Omitted hereinafter] [*6]


The above is the original text of the report. Though some details might have been painful to read, these are the things that actually occur in the laboratories which conduct animal testing. We strongly believe that it is a part of reality that we must be aware of.

As we presumed, the report had a lot of sections which had been left blank (despite the fact that it says, Eeach item must be filled out E) We think it is a good idea that these reports are compulsory, but is it too much trouble for the researchers to record every details? It is painful to learn the truth; however, we feel as if those researchers who mention details are somewhat more concerned about the animals than others who do not.

Although we can only estimate the number of deaths due to miscarriage and stillbirth, we believe that the actual number could be very high. We also feel that the number of death among young individuals is quite high.

Moreover, we are awfully saddened by the calculations of ages. There are those who died young, and others who had spent confined life for close to 30 years. Although it is not known whether they all lived together, we are especially saddened by the news of three Crab-eating macaques who passed away about one month ago one after another. They arrived on 6/20, 21/1989, and lived as experimental subject for 14 years.

This report refers only to the year of 2003, but we know from the past reports as many monkeys die from experiments as accidents or illness. We must not forget about the fact that monkeys are used for experiments, but we would also like to inform you about those monkeys who spend their entire lives at the laboratories.


[*1: Playground #4 supposed to be a new one for preparing National Bioresource Project. Though causes for external wound were not mentioned, wouldn’t it be a problem that this type of accident occurred right after transferring the monkey?]

[*2: Researchers are annoyed by the fact that the monkeys in captivity for experimental purpose often die from gastric flatulence. It is believed to be due to stress but the real cause is unknown.]

[*3: Wisconsin General Test Apparatus, an experimental apparatus which was invented by infamous Harry Harlow.]

[*4: Why did they separate the baby from her mother?]

[*5: There were two cases where mother Japanese macaque was holding the baby and two cases for Rhesus monkey.]

[*6: There were six miscarriage/stillbirth incidents for Japanese macaque and one for Cotton-top Tamarin.

Homepage of Kyoto University’s Primate Research Institute

Experimental Animals

Copyright (C) 2000-2008 AVA-net All Rights Reserved.