Biomedical Engineering Reference
In-Depth Information
TABLE 7.2
Behavioral Assessment Scale for Abnormal Behaviors in Monkeys
Scale
Behavior
Possible Action
Mild
Whole body stereotypies (e.g. pacing) from which the animal
can be diverted
Routine monitoring
Mild
Self-directed stereotypies (e.g. digit sucking) that do not
interfere with other functions such as breeding, parental care,
eating, or drinking
Routine monitoring
Substantial
Whole body stereotypies from which the animal cannot be
diverted
Rule out alternatives
Increased enrichment
Pharmacotherapy
Substantial
Self-directed stereotypies that interfere with other biological
functions
Rule out alternatives
Increased enrichment
Training
Pharmacotherapy
Severe
Self-injurious behavior
Depending on severity, may require immediate
pharmacotherapy
there is no conclusive proof that the activity is detrimental to
the animal and for which there may actually be some benefit
to the animal (e.g. the physiological benefits of exercise) are
rated as the least problematical (i.e. “mild”). In contrast,
abnormal behaviors that may compromise the health of the
animal are termed pathological and are considered the most
problematical (“substantial” or “severe”). A behavioral
assessment scale may prove useful to scientists, veterinar-
ians, facility managers, and animal care personnel as
a standardized means of assessing the behavioral profile of
their nonhuman primates. For example, animals that have
been classified with a rating of severe should receive prompt
medical attention and therapeutic intervention. Animals that
are rated at lower levels should receive attention at a corre-
spondingly appropriate level.
achieved by rearing infants in social groups containing
mothers and other young. The mother-peer condition is
considered an ideal regimen for raising infant rhesus
monkeys in the laboratory. For the biomedical researcher or
the veterinarian, however, several other options are also
available.
For research requiring continued direct access to infants
or for veterinary reasons (i.e. mother has rejected an infant
at birth) or for facility operations (mother-peer groups are
not possible), two other rearing conditions may be relevant.
These are peer-only rearing and surrogate-peer rearing.
Although species-normative patterns of behavior develop
in both rearing conditions, each rearing procedure has its
own risks and benefits as summarized earlier. Surrogate-
peer rearing may be particularly desirable for those studies
in which infants must be accessed individually on a regular
basis. Because surrogate-peer reared infants form their
primary attachment to an inanimate surrogate and not to the
peers they are exposed to for several hours per day, the
infants can be studied without distress during a nonsocial
period. Infants can readily be removed from the cage while
still clinging to their surrogates and even subjected to
simple veterinary or experimental manipulations like blood
drawing or injections under these conditions. Although
peer-only-reared infants can be accessed individually,
separation from peers produces more powerful reactions
than removal of mother-reared infants from their mother
(
Higley et al., 1991
).
The single most important guideline to follow in rearing
infant primates is to provide them with some sort of
physical contact with conspecifics during early develop-
ment, whether it be with a mother and peers, with peers
only, or with a mother only. Failure to do so will result in
socially deficient, behaviorally bizarre monkeys that may
Prevention of Behavioral Pathology
All the research on abnormal behavior in primates shows
that once a pathological form of abnormal behavior has
developed, it is likely to be very resistant to treatment.
Moreover, animals with the same kind of pathological
behavior may respond quite differently to the same treat-
ment (
Tiefenbacher et al., 2005
). Thus, the best way to
manage pathological behavior is to prevent its occurrence.
Husbandry Decisions for Infant Primates
The development of normal behavior in nonhuman
primates is critically dependent upon early rearing experi-
ences. The optimal rearing environment is probably one in
which infants are raised in species-typical social groups.
For rhesus monkeys, such groups would consist of mothers,
other adults, adolescents, juveniles, and infants of both
sexes. However, normal behavioral outcomes can also be
