Biomedical Engineering Reference
In-Depth Information
(e.g.
Abbott et al., 1988
). Although stress appeared to be
contributory in New World species under these conditions
and in Old World species as described earlier, other envi-
ronmental effects such as airline travel and various forms of
restraint and immobilization do not appear to result in an
altered pregnancy outcome in captive macaques. It has
been noted that for pigtailed, long-tailed, and rhesus
macaques in addition to baboons, jet transport during
various periods of gestation does not alter the rate of viable
offspring (
Sackett, 1981
) or increase the rate of sponta-
neous abortion (A. G. Hendrickx, unpublished observa-
tions). Of the 154 pregnant rhesus females (GD 30
e
150)
shipped via air flight to other institutions for experimental
purposes from 1982 to 1990, only 0.7% (1/154) produced
a nonviable fetus upon arrival; no abortions either during or
within 2 weeks of shipment were observed. Other studies
have shown that daily capture of gravid pig-tailed
macaques during GD 30
e
130 does not alter gestational
length or survival of the offspring (
Newell-Morris et al.,
1989
). Experience at the CPRC indicates that frequent chair
restraint and/or hand-catching by experienced animal
handlers during all stages of pregnancy in both rhesus and
long-tailed macaques do not affect pregnancy maintenance
or outcome (
Tarantal and Hendrickx, 1988b, 1989
).
Various types of placental insufficiency have also been
associated with high rates of fetal mortality, including
infections of the placenta (placentitis) (
Kaplan, 1979
),
impaired placental circulation (infarctions and abruptio
placentae), and abnormal placental location (placenta pre-
via). The role of ultrasound in the detection of placental
abruptions, either subchorionic or retroplacental, is signif-
icant (
Tarantal and Hendrickx, 1988b
). Use of this tech-
nique, particularly for concealed hemorrhage in
conjunction with emergency hysterotomy, can result in
major improvements in maternal mortality in addition to
retrieval of viable fetal tissues for experimental purposes.
In a histological study of stillborn fetuses from a variety
of nonhuman primates species, a necropsy examination
confirmed placentitis in seven of eight cases as the primary
cause of fetal demise. The most commonly isolated
organisms responsible for ascending genital infections
leading to placentitis and subsequent fetal anoxia were
Group D streptococci and
b
-hemolytic, coagulase-positive
Staphylococcus aureus. Infection of the placenta was
accompanied by infiltration of inflammatory cells, edema,
necrosis, and hemorrhage which interfered with fetal
oxygenation (
Andrews, 1974
). Gram-positive cocci, espe-
cially
a
-hemolytic Streptococcus viridans, were implicated
in 11 of 17 cases of abortions and stillbirths in rhesus
monkeys (
Swindle et al., 1982
). Acute placentitis and fetal
bronchopneumonia were the most consistent histopatho-
logical findings in these cases.
Although it is difficult to document dystocia in
nonhuman primates because of the high incidence of night
births, contributing causes may include cephalopelvic
disproportion, positional abnormalities, uterine malforma-
tion and inertia, uncontrolled hemorrhage, and toxemia
(
Hendrickx and Giles-Nelson, 1971
). Adverse pregnancy
outcomes (i.e. stillbirths) have been associated with breech
rather than cephalic presentation in term pregnancies of
long-tailed (
Cho et al., 1985
) and pig-tailed (
Goodlin and
Sackett, 1983
) macaques. Parturition in marmosets can lead
to complications, primarily in primiparous births (
Hill,
1969
). No evidence has linked litter size with parturition
difficulties (
Poole and Evans, 1982
).
NONHUMAN PRIMATES FROM
FOREIGN BREEDING PROGRAMS
Introduction
Recent trends in utilization of nonhuman primates for
research within the USA indicate that foreign breeding
operations will continue to be a valued source of animals
in order to meet demands within the biomedical commu-
nity. This is especially true for Macaca fascicularis,the
cynomolgus macaque. In addressing issues related to
foreign sourcing of research nonhuman primates, the
ultimate goal is to provide the appropriate research model
to the investigator, which requires production of a well-
defined research nonhuman primate relative to genetic
origin and SPF status. Furthermore, reliable animal
availability requires a secure means of transportation into
the USA, with successful completion of Centers for
Disease Control (CDC) import quarantine. Investigators
and colony managers should understand some of the
unique issues surrounding acquisition of research
nonhuman primates from foreign sources. Suppliers,
importers, and end users of these animals should contin-
ually work to improve processes to meet quality and
supply expectations.
Historical Perspective
The invaluable role of nonhuman primates in biomedical
research has always required attention to securing
adequate numbers of research quality nonhuman
primates. Research model specifications minimally
address a defined species, health status, gender, and
maturity. Since the early 1960s in the USA, the National
Institutes of Health began planning and implementing
programs to generate nonhuman primate research models
for use in federally funded research. (
Whitehair, 1999
).
For decades after inception, the National Primate
Research Centers (NPRCs) relied on feral or bred
nonhuman primates from foreign suppliers to replace and
expand breeding stock. Similarly, commercial and
academic institutions conducting research with nonhuman
