Facebook icon Instagram icon Twitter icon Contact us via E-mailContact us
AfP logo

Action for Primates

Long-tailed macaques, photo by Sarah Kite


1 March 2021: Macaques injected with toxic solvent to deliberately cause liver damage

Long-tailed macaques; photo credit Cruelty Free International
Long-tailed macaques
photo credit Cruelty Free International

Thirty male long-tailed macaques were used in this research carried out to evaluate the different stages of liver fibrosis (scarring of liver tissue) in long-tailed macaques (1). Eight of these individuals died before the study was completed. The work was done at The Third Affiliated Hospital of Guangxi Medical University in China, approved by the medical ethics committee and experimental animal ethics committee, and funded by various sources within China.

The macaques were injected subcutaneously with carbon tetrachloride twice a week. Carbon tetrachloride is used as a solvent for oils and fats, as a refrigerant and as a dry-cleaning agent. It is highly toxic and carcinogenic. Presumably to add to the liver damage suffered by these monkeys, they were also fed a high-fat diet supplemented with about 35% cholesterol and the only source of fluids given to them was an ethanol (alcohol) solution (10% in water). Every four weeks after the injection with carbon tetrachloride, the macaques were anaesthetised with ketamine in order to get liver tissue via needle aspiration. The animals were also subjected to magnetic resonance imaging (MRI). After 20 weeks, the macaques were anaesthetised with ketamine and killed by injecting air into an ear vein. Liver tissue was collected for examination.

Eight of the macaques died during the study. The remaining 22, who were killed, were all found to have fibrosis of the liver, most with severe damage. The authors of the paper provide no details of the clinical condition of the monkeys, especially those individuals who died during this appalling 'experiment'.

The aim of the work was to develop a model of liver fibrosis in the long-tailed macaque. The artificial nature of the research, the lack of application to people who suffer liver damage caused by a variety of factors (and not by injecting themselves with a solvent!) and the infliction of such severe suffering on sentient beings is morally and scientifically unacceptable. It leaves us wondering what working definition of ethics was used by the institution's medical ethics committee and experimental animal ethics committee.


  1. Ding, Ke; Liu, Manrong; Wei, Xue; Huang, Ruisui; Chen, Jiong; Lu, Shanjin; Wang, Dacheng and Lu, Wei. 2021-01-06. "Comparison of MR-PWI quantitative and semi-quantitative parameters for the evaluation of liver fibrosis" BMC Medical Imaging 21(1):8.
  2. This article is licensed under a Creative Commons Attribution 4.0 International License.

2 February 2021: Photos of rescued macaques

Here are some photos of Mona, Boim and Boris settling in at the Jakarta Animal Aid (JAAN) wildlife rescue centre, enjoying their first days of freedom from the torment and cruelty inflicted upon them by the YouTuber in Jakarta. The monkeys were confiscated by the Indonesia authorities (see our Take Action alert for more information), following complaints submitted to Dr Anies Baswedan, the Governor of Jakarta, including a report from Dr Nedim Buyukmihci, veterinary adviser from Action for Primates.

Mona, rescued long-tailed macaque; photo Jakarta Animal Aid Network
Mona, long-tailed macaque
photo Jakarta Animal Aid Network
Boim, rescued southern pig-tailed macaque; photo Jakarta Animal Aid Network
Boim, southern pig-tailed macaque
photo Jakarta Animal Aid Network
Boris, rescued long-tailed macaque; photo Jakarta Animal Aid Network
Boris, long-tailed macaque
photo Jakarta Animal Aid Network

There has been widespread news media coverage in Indonesia and condemnation of the abuse suffered by these monkeys filmed for 'entertainment' and broadcast on YouTube. The cruelty included rubbing obnoxious substances such as glue or chilli onto the monkeys' food and lighting firecrackers and sparklers to scare them.



The rescue of these monkeys demonstrates the importance of writing letters and sending E-mail to those who have the ability to make change. Although we can never know whether we will be successful every time, we can be sure that a lack of action will fail. This confiscation will, we hope, send an important message and help to deter people from mistreating non-human primates and others.

It has also shone a spotlight on YouTube and its shameful promotion of animal cruelty by allowing such abusive content to be broadcast. Despite the action taken by the Indonesian authorities, the YouTube channel continues to be available, broadcasting the sadistic and cruel treatment of non-human primates.

Please continue to send polite E-mail to Ms Susan Wojcicki, Chief Executive Officer, and ask her to enforce YouTube rules and take down all animal abuse videos: susan@google.com (clicking on Wojcicki's E-mail address will automatically Cc press@google.com)

9 January 2021: Macaques subjected to two months of unpredictable stress to simulate 'depression'

Long-tailed macaques in laboratory; photo credit SOKO Tierschutz and Cruelty Free International
Long-tailed macaques in laboratory
photo credit SOKO Tierschutz & Cruelty Free International

A group of 16 female long-tailed macaques were subjected to cruel and inhumane treatment in an attempt to simulate depression with chronic unpredictable stress (CUS), and then to study the effects of drugs (1). The chronic stressors included food and water deprivation, space restriction and restraint, loud noise, strobe light, and intimidation with fake snakes. The work was approved by and done at the Beijing Institute of Pharmacology and Toxicology, Beijing in China.

Ten of the macaques were of low social status...tended to be alone, always bullied by other monkeys and afraid to fight for food with other monkeys... These were the stress group; the other six normal macaques served as the control group. All were singly housed in barren, steel cages. For eight weeks, each individual in the stressed group was subjected to chronic unpredictable stress, two on each day lasting 12 hours each:

Stress chart; Yin, et al (1)
Stress chart; Yin, et al (1)

The macaques were observed for behavioural changes – huddling and self-clasping classed as negative depression-like behaviour and locomotion and environmental exploration as positive. After eight weeks, the individuals in the stressed group were given a test drug and their behaviours observed. The drugs apparently reduced depression-like behaviors. The fate of the macaques was not stated.

There is no doubt the monkeys suffered substantially in this research. To treat non-human primates so cruelly under the guise of science is immoral. Further, the artificial stressors inflicted on these monkeys cannot compare to the complex emotional, genetic and environmental stressors that cause mental illness and depression in humans.


  1. Yin, Yong-Yu; Tian, Chao-Yang; Fang, Xin-Xin; Shang, Chao; Zhang, Li-Ming; Xu, Qiang and Li, Yun-Feng. 2020-11-26. "The Faster-Onset Antidepressant Effects of Hypidone Hydrochloride (YL-0919) in Monkeys Subjected to Chronic Unpredictable Stress" Frontiers in Pharmacology 11:586879.
  2. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).

23 December 2020: Monkeys used to study teenage alcohol use disorder

Mother rhesus macaque and baby, Swayambhunath Temple, Nepal; photo credit Jo-Anne McArthur / We Animals
Mother rhesus macaque and baby, Nepal
credit Jo-Anne McArthur / We Animals

The work, purportedly to identify ...predictors of [human] teenage alcohol use disorder..., was done at the National Institute of Child Health and Human Development in Maryland, USA, and supported primarily by public funds. The research involved 145 laboratory-born rhesus macaques (64 females, 81 males), ...housed at the Laboratory of Comparative Ethology, National Institute of Child Health and Human Development colony as part of an ongoing, longitudinal study investigating genetic and environmental influences on neurobiology and behavior as they relate to alcohol consumption. (1)

Some of the infants (63) were allowed to remain with their mothers until 6-7 months of age, while others (82) were separated from their mothers at just 1-3 days following birth and reared in a neonatal nursery where they were given a fleece-covered object as a surrogate mother and a cloth blanket. Their behaviours were observed and recorded.

When the monkeys were about 3-4 years old, they were ...tested for their propensity to voluntarily consume alcohol. They were initially trained to drink an artificially sweetened solution from nipple-like spouts. Ethanol (alcohol) was subsequently added to the solution until an 8.4% v/v alcohol solution was produced. The ethanol solution was then made available to the monkeys for one hour each day, four days a week (Monday through Thursday), for between five and seven consecutive weeks. The monkeys were able to self-administer alcohol while housed alone or socially with other monkeys.

The assessment of alcohol intake occurred over a period of seven years and under different conditions. There were differences in alcohol consumption based on neonatal temperament. The nursery reared monkeys were more likely to consume alcohol at rates that produced intoxication when compared with mother reared monkeys. There was also a binge-like rapid intake, with about two-thirds of the available alcohol consumed in the first 15 minutes.

Aside from the immorality of using non-human primates in such despicable research – removing infant monkeys from their mothers and turning them into 'binge drinkers' – the complex combination of factors involved in human behaviour – including genetics, emotional and personal experiences, socioeconomic factors – can never be simulated in others. This research, paid for by the US taxpayer, has continued for decades and will likely continue far into the future. In the meantime, people with the disease of alcoholism will continue to suffer waiting for a 'cure' from scientists, rather than society addressing the fundamental issues that can never be resolved through non-human primate research.


  1. Wood, Elizabeth K.; Champoux, Maribeth; Lindell, Stephen G.; Barr, Christina S.; Suomi, Stephen J. and Higley, J. Dee. 2020-11-01. "Neonatal temperament and neuromotor differences are predictive of adolescent alcohol intake in rhesus monkeys (Macaca mulatta)" American Journal of Primatology 82(11):e23043.

21 December 2020: Mauritius monkeys used in sperm preservation research in USA

Young long-tailed macaques in a Mauritius monkey farm; photo credit Cruelty Free International
Long-tailed macaques, Mauritius monkey farm
photo credit Cruelty Free International

Monkeys from Mauritius have been used in research in the USA in which male long-tailed macaques were subjected to penile electrical stimulation while under sedation to collect sperm (1). Female long-tailed macaques were injected multiple times (twice-daily, by intramuscular injection, for 11 to 12 days) with recombinant human follicle stimulating hormone and once with human chorionic gonadotropin in order to cause ovarian hyperstimulation. Ovarian hyperstimulation syndrome is an exaggerated response to excess hormones and can cause the ovaries to swell and become painful. Eggs (oocytes) were retrieved by laparoscopic aspiration [incision into the abdomen and use of steel needle to withdraw eggs] between 38 to 40 h after the [human chorionic gonadotropin] injection. Fertilisation was subsequently achieved in 12 out of 15 oocytes.

Some of the macaques were supplied by Bioculture Mauritius, the others from Covance Research Products. The work was done at the Wisconsin National Primate Research Center (WNPRC) and was paid for entirely with public funds (NIH).

A recent investigation carried out by PeTA at WNPRC revealed that almost 2,000 monkeys are kept in barren metal cages. PeTA's findings make disturbing reading, including stressed monkeys displaying disturbed behaviour and causing injuries to themselves. The revelations also included male macaques being strapped into a restraint device before staff used electroshock on their penises until the animals ejaculated. Because the authors of the paper we report here stated that sperm from the monkeys were collected through penile electrical stimulation, we have to assume the method discovered by PeTA was used on the monkeys from Mauritius.

The stated goal of the research on the Mauritian macaques was to develop a protocol for freezing the sperm to provide an effective way to preserve it, to facilitate in vitro fertilisation (IVF) experiments and to allow the application of genome editing strategies in these Mauritius monkey embryos. None of this, of course, is intended to help Mauritian macaques, not could it ever be the case. Instead, the information will ...be used to create a [Mauritian cynomolgus macaques] sperm cryobank and as a model for genetic engineering. Once again, monkeys are being treated as living 'test tubes', with no concern for their well-being or providing them with the dignity and moral constraints that are routinely afforded people.


  1. Strelchenko, Nick S.; Schmidt, Jenna Kropp; Mean, Katherine D.; Schotzko, Michele L.; Golos, Thaddeus G. and Slukvin, Igor I. 2020-09-02. "Cryopreservation of Mauritian Cynomolgus Macaque (Macaca fascicularis) Sperm in Chemically Defined Medium" Journal of the American Association for Laboratory Animal Science ePub.