Fumiaki Cho

Differentiation of mitochondrial DNA types inMacaca fascicularis

Restriction fragment length polymorphism in the mitochondrial DNA ofMacaca fascicularis from four geographical regions, Indonesia, the Philippines, Malaysia, and Indochina, was analyzed. In total, 21 types of mitochondrial DNA were detected using five restriction enzymes. These types were divided into two main groups based on phylogenetic analyses, one of which corresponded to the types of continental (Malaysia/Indochina) populations and the other to the types of a insular (Philippine) population. The types in the Indonesian population belonged to both groups. In the phylogenetic tree for the four populations, two clusters were constructed, one for the continental populations and the other for the insular ones.

Mother-infant interactions of wild-born, individually-caged cynomolgus monkeys (Macaca fascicularis) during the first 14 weeks of infant life

This study documents age-related changes in the interactions of wild-born cynomolgus macaque mothers and their infants living in individual cages during the first 14 weeks of infant life. Body contact between mother and infant, maternal holding, and infant sucking were found to decrease, and the mothers showed an increased frequency of aggression toward their infants with age. These results were broadly similar to those reported for mother-infant interactions in other macaques living in social groups. Nevertheless, a clear difference between the present cynomolgus macaques and other macaques in social groups was apparent. The cynomolgus macaque mothers tended to permit their infants to move about freely without displaying maternal protectiveness such as restraint or retrieval, unlike other macaque mothers in social groups. Such maternal behaviors might derive from the experience of living in individual cages for many years and the relative safety of living in individual cages. The lack of maternal restraint and retrieval could be responsible for the observed sex differences in behavior: male infants moved more actively, and broke, and made contact with their mothers more frequently than did female infants. Moreover, mothers of female infants held and groomed them more frequently and were less aggressive toward them.

In vitro fertilization and preimplantation embryo development of African green monkeys (Cercopithecus aethiops).

Ovaries of five adult female African green monkeys were stimulated by repeated administrations of equine chorionic gonadotrophin (eCG), followed by a single administration of human chorionic gonadotrophin (hCG). Oocytes were collected from enlarged follicles 28 h after hCG administration and incubated in vitro for 288 h. Oocytes that had extruded the first polar body were inseminated with spermatozoa that had been incubated for 4 to 6 h in medium with caffeine and dibutyryl cyclic AMP. Of these oocytes, 66% were fertilized and the incidence of polyspermy was 37%. Eighty‐two percent of the fertilized eggs cleaved, with some developing into expanded blastocysts. Am. J. Primatol. 43:43–50, 1997.

A two‐step extraction method to measure fecal steroid hormones in female cynomolgus monkeys (Macaca fascicularis)

We developed a two‐step extraction method for measuring fecal steroid concentrations. In the first step, distilled water was used to extract steroids from fecal samples. In the second step, a mixture of organic solvents (hexane and ether) was used to re‐extract water extracts that had been transferred to a glass tube. A portion of the upper layer of the organic solvents was transferred to separate assay‐tubes for measurement of estradiol (E2) or progesterone (P), and the organic solvents were evaporated in vacuo.

Localization of testosterone and 3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase in cynomolgus monkey (Macaca fascicularis) testes

The enzyme 3β‐hydroxysteroid dehydrogenase /Δ5‐Δ4‐isomerase (3β‐HSD) is essential for the biosynthesis of all classes of steroid hormones, including androgens. We localized testosterone and 3β‐HSD by light microscopic immunocytochemistry in the testes of adult cynomolgus monkeys. Immunoreactive testosterone was located as intense deposits in the labeled cytoplasm of Leydig cells, and located weakly in the interstitial tissues, basement membranes, and the regions near tubular walls within tubules. Immunoreactive 3β‐HSD was located in the cytoplasm of all Sertoli cells and was especially intense in the parts near tubular walls and located weakly to intensely in the cytoplasm of some Leydig cells. This is the first immunocytochemical evidence that Sertoli cells of cynomolgus monkeys, as well as Leydig cells, are involved in biosynthesis of androgens.

Localization of immunoreactive testosterone and 3β-hydroxysteroid dehydrogenase/Δ5-Δ4 isomerase in cynomolgus monkey (Macaca fascicularis) testes during postnatal development

Abstract: The age‐related expression of testosterone and 3β‐HSD in the testes of cynomolgus monkeys was detected using light‐microscopic immunocytochemistry. Intense deposits of immunoreactive testosterone were labeled in parts of Leydig cells in neonatal, late infantile, pubertal, and adult testes, and only a few Leydig cells in early infantile testes. The immunoreactive 3β‐HSD was labeled in parts of Leydig cells and in all Sertoli cells in neonatal, late infantile, pubertal, and adult testes, whereas only a few Leydig cells, but no Sertoli cells, were labeled in early infantile testes. The fluctuations of testosterone and 3β‐HSD expression in testes correlated well with those already observed plasma testosterone levels during postnatal development in cynomolgus monkeys.

Polymorphism in the mitochondrial DNA of cynomolgus monkeys

Variations in the mitochondrial DNA of a total of 150 cynomolgus monkeys (Macaca fascicularis) from Indonesia, the Philippines, and Malaysia were studied using a restriction endonuclease, EcoRI. Three distinct patterns were detected and they were denoted as morph 1, 2, and 3. The Malaysian population proved to be significantly different from the remaining two populations in the distributions of the three EcoRI morphs.

Comparison Between Wild-born Mother-female Infant Interactions and Laboratory-born Mother-female Infant Interactions During the First 14 Weeks After Birth in Individually Caged Cynomolgus Macaques

In this study we compared mother-female infant interactions between primiparous and multiparous laboratory-born (F1) cynomolgus macaques (Macaca fascicularis) in individual cages at Tsukuba Primate Center (TPC), Japan, during the first 14 weeks of infant life. We also compared interactions between multiparousF1 mothers and their female infants with those between wild-born mothers and their female infants when mothers and their infants were housed in the same individual cages. PrimiparousF1 mothers showed significantly higher values for contact with and holding of their infants than multiparousF1 mothers. The primiparousF1 mothers also tended to behave aggressively toward their infants when the latter did not show any obviously irritating behaviors. Thus, the primiparousF1 mothers seemed to be inconsistent in terms of maternal behavior. Compared with multiparous wild-born mothers, multiparousF1 mothers moved more frequently, held their infants less frequently and acted aggressively toward their infants less frequently. However, infants ofF1 mothers, as well as infants of wild-born mothers, interacted with their mothers through approaching and playful contact with them. These findings indicate that the attitude of multiparousF1 mothers toward their infants was relatively passive. Possible reasons for the passive maternal style of multiparousF1 mothers are discussed.

Hour of delivery in cynomolgus monkeys under indoor individually-caged conditions

The hour of delivery was surveyed in 152 cynomolgus monkeys (Macaca fascicularis) which were kept in individual cages placed in completely air-conditioned and artificially lit rooms. The deliveries took place during light hours (05:00–19:00) in 15 animals (10%) and during dark hours (19:00–05:00) in 137 (90%). No significant differences in delivery hour were observed between animals of feral origin and colony-bred F1 animals. In addition, there was no difference according to gravidity.

Human-type ABO blood groups as genetic markers for the management of a squirrel monkey (Saimiri sciureus) breeding colony

The human-type ABO blood groups were determined for 94 families of the squirrel monkey which included 151 animals. Four phenotypes of ABO blood groups (A, B, AB, and O) were detected. Family analysis revealed that the human-type ABO blood groups in this species were governed by three alleles, codominantA andB and silentO. There were intraspecific differences in the distribution of phenotypes and gene frequency among three populations imported by different routes at different times. The usefulness of ABO blood groups for defining the genetic variability of a squirrel monkey breeding colony through successive generations is discussed on the basis of the difference in distribution of ABO blood groups between wild-originated parental and its first colony-born populations.