Reader Comments
Post a new comment on this article
Post Your Discussion Comment
Please follow our guidelines for comments and review our competing interests policy. Comments that do not conform to our guidelines will be promptly removed and the user account disabled. The following must be avoided:
- Remarks that could be interpreted as allegations of misconduct
- Unsupported assertions or statements
- Inflammatory or insulting language
Thank You!
Thank you for taking the time to flag this posting; we review flagged postings on a regular basis.
closeSocial isolation of monkeys
Posted by markgbaxter on 08 Jul 2013 at 23:16 GMT
The research described in this article makes use of monkeys housed in Chinese breeding facilities, who are weaned early in life (six months of age), peer-reared, and then singly housed beginning at 3 years of age. Nearly 20% of these monkeys displayed clusters of behaviors reminiscent of depression or anxiety, and far more exhibited abnormal behaviors including stereotypies. As the authors note, these are known consequences of single housing in macaque monkeys.
Although the housing conditions of the monkeys were dictated by the breeding colony in China and not by the authors' research agenda, it is worth noting that this style of nonhuman primate housing for experimental purposes would almost certainly be impermissible in either the United States (see Guide for the Care and Use of Laboratory Animals, http://www.nap.edu/catalo...) or the United Kingdom (see NC3Rs guidelines for primate accomodation, care, and use, http://www.nc3rs.org.uk/d...).
This article is useful in that it underscores the consequences on behavior of breeding and housing conditions. Researchers that make use of macaque monkeys from Chinese breeding colonies (either directly or indirectly) should make themselves aware of the housing conditions used by the facility in question and should consider the consequences of potential behavioral abnormalities, reported by these authors, on their study outcomes. The frequency of abnormal behaviors exhibited by the monkeys described in this article would make them unsuitable for many research protocols in which behavioral or cognitive measures are primary outcomes.
Mark Baxter PhD
Professor of Neuroscience
Icahn School of Medicine at Mount Sinai, New York, USA
RE: Social isolation of monkeys
ebezard replied to markgbaxter on 20 Jul 2013 at 10:44 GMT
We now have the confirmation that the depressive-like profiles described here cannot only be due to single-housing, although such condition increases the occurrences of atypical behaviours. Indeed we recently published the follow-up study performed among group-housed subjects that were never single-housed and reported similar results (Camus SM, et al. (2013) Birth Origin Differentially Affects Depressive-Like Behaviours: Are Captive-Born Cynomolgus Monkeys More Vulnerable to Depression than Their Wild-Born Counterparts? PLoS ONE 8(7): e67711).
Although these breeding procedures for non-human primate farms might not be permissible in the USA or the UK (the shipment of animals do not imply single housing in these countries?), they are common and legal in China, which has become the world N°1 producer of bred non-human primates. They provide macaques to the whole Japanese, American and European toxicology industry and research laboratories. Instead of ignoring or reprehending these farms, we should on the contrary seek into the exact breeding conditions and investigate the inter-individual behavioural responses displayed in such conditions. Such studies could serve several purposes, such as (i) identifying a new model of depressive disorder and investigating the underlying etiological and physiopathological mechanisms of this disease, (ii) discriminating between pathological / healthy subjects and improving the validity of control groups in every protocols performed with macaques (measuring behavioural, cognitive, but also physiological outcomes), and (iii) establishing the parameters to modify in breeding facilities in order to enhance animal wellbeing.