Self-aggression in macaques: Five case studies

Abstract

ABSTRACT. Spontaneous self-aggressive behaviors Were observed in five adult male rhesus monkeys (Macaca mulatta) housed at a university facility..all were individually caged, were free of intercurrent disease, and were being utilized in ongoing research studies. The self-aggressive behaviors observed included self-biting, self-clasping, self-slapping, self-rubbing and threatening of body parts. In several cases, wounds were inflicted and medical treatment was required due to the severity of the lesions. A review of the animals' clinical histories revealed an increased level of self-aggressive behavior in four of five monkeys during such stressful or stimulating conditions as movement of the animal tO a new cage, movement of animals out of the room or escape of other monkeys from their cages. The frequency with which these behaviors occurred was quantitated experimentally. The results revealed an increased level of self-aggressive behavior in two of these animals during the videotaped sessions in response to aggressive contacts with the investigator. In contrast, one monkey exhibited self-aggressive behavior both clinically and experimentally in the absence of environmental stimuli or human contact. Clinical management of self-aggressive monkeys included housing monkeys only with physically smaller primates, decreasing the level of environmental stimuli, and drug therapy. Haloperidol was used with success in one animal that exhibited severe self-aggressive behavior.

Enrichment and aggression in primates

“…Reinhardt and Rossell, 2001) it nevertheless appears to be more common in singly-housed individuals and those that experienced socially restricted development Chamove, 1980, 1985;Brent et al, 1989b;Chamove et al, 1984;Gluck and Sackett, 1974;Pond and Rush, 1983;Reinhardt and Rossell, 2001;Woolverton et al, 1989). Furthermore this behaviour can be accentuated by a number of conditions including frustration (Gluck and Sackett, 1974), self-reward (Anderson and Chamove, 1980), excessive management disturbance , withdrawal of enrichment (Bryant et al, 1988;Chamove et al, 1984), tension or anxiety related to human presence (Pond and Rush, 1983;Skyner et al, 2004) and social contexts (Anderson and Chamove, 1980;Erwin et al, 1973). It has been suggested that it arises as the result of the absence of 'appropriate social aggression targets' during development when young animals would otherwise be involved in play-fighting (Anderson and Chamove, 1980), of self-stimulation when in an otherwise unstimulating environment , or of the development of a coping strategy to reduce arousal in distressing situations (Novak, 2003).…”

“…Anderson and Chamove (1980) describe self-aggression as behaviour that is 'abnormally frequent and/or intense threats or physical attacks directed towards one's own body which may or may not result in tissue damage' and while the causes of this behaviour remain unclear (see e.g. Reinhardt and Rossell, 2001) it nevertheless appears to be more common in singly-housed individuals and those that experienced socially restricted development Chamove, 1980, 1985;Brent et al, 1989b;Chamove et al, 1984;Gluck and Sackett, 1974;Pond and Rush, 1983;Reinhardt and Rossell, 2001;Woolverton et al, 1989). Furthermore this behaviour can be accentuated by a number of conditions including frustration (Gluck and Sackett, 1974), self-reward (Anderson and Chamove, 1980), excessive management disturbance , withdrawal of enrichment (Bryant et al, 1988;Chamove et al, 1984), tension or anxiety related to human presence (Pond and Rush, 1983;Skyner et al, 2004) and social contexts (Anderson and Chamove, 1980;Erwin et al, 1973).…”

“…It is known that the presence of people particularly in large numbers at zoos (Chamove et al, 1988;Hosey, 2005;Skyner et al, 2004) or related to negative stimuli (e.g. Pond and Rush, 1983) can have a negative effect on primates. The possibility and evidence that positive interactions and training in particular can have an enriching effect on primates will not be discussed here.…”

Self-biting with multiple finger amputations following spinal cord injury

“…Spontaneous self-aggression including extensive biting of the upper limbs has also developed in housed Macaques experiencing stress (Pond, 1983). Both of our patients related fingernail biting, which progressed to severe mutilation, to anxiety and depression.…”

Social and environmental influences on self-aggression in monkeys

“…The following conditions are reported to increase SA: frustration (GLUCK & SACI,:ETT, 1974), sexual arousal (MAPLE, ERWIN & MITCHELL, 1974), ovarian hormonal state (BIELERT & HOWARD-TRIPP, 1983), pain (LEVINE et al, 1970) and threatening stimuli (ALLYN, DEYME & BEGUE, 1976;CHAMOVE & HARLOW, 1970;CROSS & HARLOW, 1965;POND & RUSH, 1983), but whether or not SA, social aggression or some other reaction will occur depends upon interactions among experiential, situational and other variables that are not well understood.…”