Fetal ultrasonography: biometric data from four African primate species

BACKGROUND: Nonhuman primates are raised in large numbers in research centers and zoos. Reproductive monitoring is required to improve breeding performances. Ultrasonography is a safe method to determine gestational age and to estimate the date of parturition. However only few data are available in nonhuman primates. METHODS: Fetal biometric data were obtained throughout pregnancy on four African primate species, namely chimpanzee, gorilla, mandrill and patas monkey. Measurements included biparietal diameter, transverse abdominal diameter, femur and humerus length, external interorbital diameter, and fetal heart rate. Curves established from these data were compared with previously published data in chimpanzees and gorillas and with those for humans and other closely related primate species. RESULTS: The curves for the different hominids were very similar, while those for mandrills more closely resembled baboons and data for patas monkeys were comparable to those for macaques. CONCLUSIONS: These data, by providing a tool to evaluate precise gestational age, will be useful for centers raising these four primate species.     

Reproductive and neonatal outcomes in captive bred baboons (Papio hamadryas)

Abstract: Baboons are widely used in biomedical research. Although it is widely held that Papio hamadryas breed well in captivity, each established colony has a different reproductive success often hypothesised to be due to husbandry practices. The National Baboon Colony in Australia is a unique colony that houses Papio hamadryas to mimic that structure seen in the wild. In this article; we have analysed their reproductive parameters and neonatal outcomes. The success of the colony husbandry practices was demonstrated by lack of maternal mortality, low foetal morbidity, and known maternal and paternal linage.     

The baboon model (Papio hamadryas) of fetal loss: maternal weight,age, reproductive history and pregnancy outcome

Background Several risk factors are associated with the incidence of human stillbirths. The prevention of stillbirths in women is a pressing clinical problem. Methods We reviewed 402 pathology records of fetal loss occurring in a large baboon (Papio spp.) colony during a 15‐year period. Clinical histories of 565 female baboons with one or more fetal losses during a 20‐year period were analyzed for weight, age, and reproductive history. Results Fetal loss was most common at term (35.57%) and preterm (28.61%) and less common in the first half of gestation (11.20%) and post‐term (5.22%). Greater maternal weight, older age, history of stillbirth and higher parity were independent predictors for stillbirth. An exponential increase in the incidence of fetal loss was observed beginning at age 14 years in baboons. Conclusions Fetal loss and maternal risk factors associated with stillbirths in baboons were similar to those documented in women.     

Abdominal pregnancy in a baboon: a first case report

The abdominal pregnancy is a rare, but life threatening complication of ectopic embryo implantation. Only three cases of abdominal pregnancy have been previously described in primates: in a squirrel monkey, owl monkey and in a rhesus macaque. A 14-year-old wild-caught olive baboon (Papio cynocephalus anubis) was diagnosed at the ultrasound examination with advanced gestational age extrauterine pregnancy. At the initial laparotomy and necropsy the diagnosis of abdominal pregnancy was made on Studdiford's criteria. This case indicates the possibility of developing a model for further study of different types of ectopic pregnancy and indicates a cesarean section as a risk factor for abdominal pregnancy.     

Osteopenia and osteoporosis in adult baboons (Papio hamadryas)

BACKGROUND: Little is known about the degree to which baboons, an important animal model in skeletal research, spontaneously experience age-related osteopenia and osteoporosis. METHODS: We measured bone mineral density (BMD) in 667 baboons, assigned T-scores to older animals based on sex-specific young adult reference groups, and compared reproductive history in older females with low BMD to those with normal BMD. RESULTS: Approximately 25% of older baboon females were osteopenic. No females or males were osteoporotic. Neither parity nor interbirth interval spine clearly distinguished low vs. normal BMD groups. Intersite correspondence in low BMD was highest between sites in the same region rather than sites of the same bone type. CONCLUSION: As with humans, osteopenia is common among older females. The absence of osteoporotic animals may be due to colony maintenance resulting in truncation of the aged population and selection for healthier animals in the oldest ranges.     

Assessment of early placental development in the cynomolgus monkey (Macaca fascicularis) using colour and pulsed wave Doppler sonography

Abstract: Colour flow mapping and pulsed wave Doppler were used to assess the process of placental growth and development in the cynomolgus monkey from 32 to 71 days gestational age. Fetal and maternal vessels were reliably visualised and insonated. Accurate longitudinal non-invasive assessment of placentation is possible using this technique.     

Trisomy 17 in a baboon (Papio hamadryas) with polydactyly, patent foramen ovale and pyelectasis

Trisomy 13 in humans is the third most common autosomal abnormality at birth, after trisomy 21 and trisomy 18. It has a reported incidence of between 1:5,000 and 1:30,000 live births. It is associated with multiple abnormalities, many of which shorten lifespan. We describe here the first reported case of a baboon (Papio hamadryas) with trisomy of chromosome 17, which is homologous to human chromosome 13. The trisomic infant was born to a consanguineous pair of baboons and had morphological characteristics similar to those observed in human trisomy 13, including bilateral polydactyly in the upper limbs, a patent foramen ovale, and pyelectasis. Molecular DNA analysis using human chromosome 13 markers was consistent with the affected infant inheriting two copies of chromosome 17 derived from the same parental chromosome. This trisomy was, therefore, due to either an error in meiosis II or the result of postzygotic nondisjunction. The parental origin, however, could not be determined.     

Sonographic biometrical normograms and estimation of fetal weight in the baboon (Papio anubis)

Background  In order to consider the non-human primate as an adequate model for studying prenatal diagnosis and therapy, comparative data on fetal growth should be available.
Methods  Sixty ultrasound scans were performed in 22 baboons between 14 and 167 days of gestation. Measurements included greatest length, head circumference, biparietal diameter (BPD), transcerebellar diameter, abdominal circumference (AC), femur length (FL), and amniotic fluid index. For all parameters growth curves were established and compared with human curves. In 18 animals, birth weight and placental weight were determined. Different equations described in the literature for estimating the human fetal weight were tested in the baboon.
Results  The fetal and placental growth pattern in the baboon was comparable with humans. The best predictor of fetal weight was the formula presented by Combs: 0.23966 × AC² × FL + 1.623 × BPD³.
Conclusions  A high similarity between baboon and human growth charts is shown. The best equation for estimating the baboon fetal weight is proposed.     

Radioimmunoassay of luteinizing hormone in the baboon (Papio hamadryas)

A heterologous radioimmunoassay (RIA) for luteinizing hormone (LH) consisting of a cynomolgus LH tracer and an antiserum raised against human chorionic gonadotropin (cynLH:anti-hCG) fulfilled the recognized criteria of reliability when applied to baboon (Papio hamadryas) plasma and pituitary extracts obtained in different endocrine conditions. This RIA is 5.5 times more sensitive than the ovine (oLH:anti-oLH) system, yields estimates of baboon LH (bLH) fairly close to those obtained by in vitro bioassay, and recognizes all bioactive molecular species of bLH present in male and female pituitary extracts. However, the system yields slightly but significantly lower estimates of bLH than the in vitro bioassay.     

Hematology and blood biochemistry in infant baboons (Papio hamadryas)

Although published normative reference standards for hematologic and clinical chemistry measures are available for adult baboons, their applicability to infants has not been addressed. We analyzed these measures in 110 infant baboons (55 females and 55 males) from a large breeding colony at the Southwest Regional Primate Research Center in San Antonio, Texas. The sample consists of olive baboons and olive/yellow baboon hybrids, 1 week to 12 months of age. We produced cross-sectional reference values and examined the effects of age, sex, and subspecies on these variables. Hematology reference ranges for infant baboons are similar to, but wider than, those for adults. Reference ranges for blood biochemistry measures are generally more dissimilar to adults, indicating that for many variables, reference ranges for adult baboons are not adequate for infants. Although sex and subspecies differences are rare, age accounts for more than 10% of the variance in many of the variables.     

Sparganosis in wild-caught baboons (Papio cynocephalus anubis)

BACKGROUND: Sparganosis is the infection of a paratenic host with the plerocercoid metacestode of Spirometra spp. A 12-year-old captive, pregnant, wild-caught baboon from Tanzania had multiple subcutaneous nodules. METHODS: Examination of the biopsied nodules revealed the presence of viable metacestodes. The histological morphology of the metacestodes was consistent with the genus Spirometra and other pseudophyllidean cestodes. Since species of Spirometra produce growth hormones that are active in mammals, we measured fetal and placental growth and hormone levels. Blood samples were taken from the mother and the cesarean-derived fetus for hematological, biochemical, and hormonal analyses and to test for the presence of antispargana antibodies. RESULTS: Baboon placental weight and fetal hematological, biochemical, and morphometric parameters were within normal ranges. Antibody titers to spargana did not differ significantly between mother (1.08 OD(405)) and fetus (0.91 OD(405)). Baboon maternal insulin-like growth factor and growth hormone values were also within the normal range. Estradiol and progesterone analysis in four of these animals (antibody titers ranged from 0.71 to 1.7 OD(405)) showed no statistically significant difference with age- or phase-matched cycle parameters compared with antibody-negative females. CONCLUSIONS: Based on the results that have been obtained, sparganosis did not appear to affect the endocrinological profile of pregnant and cycling female baboons.     

A baboon (Papio hamadryas) model of insulin-dependent diabetes

Over a period of four years, streptozocin has been used to induce diabetes in 10 baboons, all of whom are insulin dependent. We describe our experience with their husbandry, induction of diabetes, insulin therapy, metabolic control and growth rate. Streptozocin dosage of 60 mg/kg readily induces hyperglycemia with minimal hepatic or renal toxicity. Using a once daily injection of mixed short and intermediate acting insulins at a dosage of 2–4 U/kg, it is possible to maintain a degree of metabolic control similar to that attained in patients.     

Spontaneous neoplasia in the baboon (Papio spp.)

BACKGROUND: There are several comprehensive reviews of spontaneous neoplasia in non-human primates that compile individual cases or small numbers of cases, but do not provide statistical analysis of tumor incidence, demographics, or epidemiology. METHODS: This paper reports all spontaneous neoplasms (n = 363) diagnosed over a 15-year period in a baboon colony with an average annual colony population of 4000. RESULTS: A total of 363 spontaneous neoplasms were diagnosed in 313 baboons: 77 cases were males (25%) and 236 were females (75%); ages ranged from 1 month to 33 years (mean 16.5, median 17). CONCLUSIONS: The organ systems affected in descending order of number of neoplasms were hematopoietic organs (n = 101, 28%), urogenital tract (n = 78, 21%), integument (n = 43, 12%), alimentary tract (n = 43, 12%), endocrine organs (n = 40, 11%), nervous system (n = 33, 9%), musculoskeletal system (n = 5, 1%), and respiratory system (n = 4, 1%). Malignant cases numbered 171 (47%); 192 (53%) cases were benign.     

The brachial plexus in the chacma baboon (Papio ursinus)

Abstract: The brachial plexus in each of ten embalmed, mature chacma baboons was dissected to document the structure and branching pattern of this nerve plexus in this increasingly used research animal. In general, the brachial plexus in the chacma baboon was similar to the plexuses in the vervet and other Old World monkeys. However, several aspects were comparable to those observed in domestic animals. Thus the bipedal and quadrupedal abilities of the chacma baboon were reflected in the structure of its brachial plexus.     

Crossing the Red Sea: phylogeography of the hamadryas baboon, Papio hamadryas hamadryas

The hamadryas baboon (Papio hamadryas hamadryas) is found both in East Africa and western Arabia and is the only free-ranging nonhuman primate in Arabia. It has been hypothesized that hamadryas baboons colonized Arabia in the recent past and were possibly even transported there by humans. We investigated the phylogeography of hamadryas baboons by sequencing a portion of the control region of mtDNA in 107 baboons from four Saudi Arabian populations and combing these data with published data from Eritrean (African) P. h. hamadryas. Analysis grouped sequences into three distinct clades, with clade 1 found only in Arabia, clade 3 found only in Africa, but clade 2 found in both Arabian and African P. h. hamadryas and also in the olive baboon, P. h. anubis. Patterns of variation within Arabia are neither compatible with the recent colonization of Arabia, implying that baboons were not transported there by humans, nor with a northerly route of colonization of Arabia. We propose that hamadryas baboons reached Arabia via land bridges that have formed periodically during glacial maxima at the straits of Bab el Mandab in the southern Red Sea. We suggest that the genetic differentiation of Arabian from African populations suggests that Arabian populations have a higher conservation status than recognized previously.     

Teratoma with trisomy 16 in a baboon (Papio hamadryas)

A teratoma was found during a planned cesarean section in a 10-year-old primigravida baboon. This teratoma had a female sex chromosome complement and trisomy for chromosome 16. This is the first report of a teratoma in a baboon and the first report of a chromosomal abnormality in a nonhuman primate teratoma. It is also the first case in a nonhuman primate to address the mechanism of origin. Through the use of genetic markers from human chromosomes 5, 8 and 17, the origin of the teratoma was shown to be most consistent with failure of meiosis II or endoreduplication in a mature ovum, while the trisomy for chromosome 16 originated after the formation of the tumor. Am. J. Primatol. 46:323–332, 1998. © 1998 Wiley-Liss, Inc.     

Trisomy of chromosome 18 in the baboon (Papio hamadryas anubis)

Trisomy 18 is usually a lethal chromosomal abnormality and is the second most common autosomal trisomy in humans, with an incidence of 1:8000 live births. It is commonly associated with abnormalities of the lower and upper extremities, having the frequency of 95% and 65%, respectively. A newborn female olive baboon (Papio hamadryas anubis) was diagnosed with intrauterine growth retardation and severe arthrogryposis-like congenital joint deformities. Cytogenetic analysis including G-banding and fluorescence in situ hybridization (FISH) revealed that the congenital abnormalities were associated with chromosomal mosaicism for trisomy 18. Genetic analysis with microsatellites from chromosome 18 confirmed the maternal origin of the extra chromosome 18. This is the first report of trisomy 18 in the baboon, which may be a promising animal model of human disease.