Adult Japanese Monkeys Research Articles

Experimental central serous chorioretinopathy in monkey eyes: fluorescein angiographic findings.

In an adult Japanese monkey (Macaca fuscatus), intravenous injections of adrenalin were repeated daily: 0.125 mg/kg for 7 days and 0.375 mg/kg from the 11th day on. In a cynomolgus monkey (Macaca irus), daily injections were carried out with intravenous adrenalin (0.11 mg/kg for 12 days and a double dose from the 13th day on) and also with intramuscular prednisolone. After the 39th injection in the former and after the 32nd injection in the latter monkey, disciform serous retinal detachment was seen to occur in the posterior pole region, and fluorescein angiography revealed multiple dye leakage spots at the level of the retinal pigment epithelium. Sometimes these changes subsided, but on continuing injections, these changes recurred on new locations. Two types of fluorescein leakage spots were recognized, i.e. ink blot type with progressive simple enlargement with time and the mushroom or jet type showing these patterns during enlargement. No abnormality was found in the optic disc, retinal vessels or in the choroidal circulation. The fluorescein angiographic findings were in close resemblance with those seen in the human central serous chorioretinopathy. It was discussed that these fundus changes of the monkey eye produced by repeated adrenalin injections would serve as a good animal model of the human disease.

On the correlation between sexual behavior and ovarian hormone level during the menstrual cycle in captive Japanese monkeys

The amount of estradiol and progesterone in the systemic blood plasma of six adult female Japanese monkeys was measured by radioimmunoassay. Data on heterosexual pairing tests was also collected and examined for correlation with these hormones. The relationship between ovarian hormones and frequency of ejaculation varied with each female. In nine normal menstrual cycles, the frequencies of invitation and approach by the female reached peaks on the day of the estradiol surge, after which they rapidly decreased. Frequencies of male behaviors including approach, leaving, invitation, and yawning significantly decreased during the luteal phase, as compared with those at the midcycle. Grooming by both sexes of the partner reached low points during the late follicular phase. The number of ejaculations per test increased significantly at the midcycle and reached a maximum a few days after the estradiol surge. The present results suggest that female proceptivity is highly correlated with the amount of estradiol, but her attractiveness is little correlated with estradiol and is lowered by progesterone.

Scanning electron microscope observation of the seminal vesicle in the Japanese monkey with special reference to intraluminal spermiophagy by macrophages.

The seminal vesicle of the adult Japanese monkey was observed by scanning electron microscopy. A number of spermatozoa are found scattered on the luminal surface. Some of them are normal in appearance, while others disintegrated. The epithelial cells bulging slightly into the lumen are devoid of cilia, but provided with diffusely distributed microvilli. The fracture surface reveals that the epithelium of the seminal vesicle consists of columnar epithelial cells with secretory activity and occasional basal cells, in accordance with the finding obtained by transmission electron microscope in other mammals. The most striking observation of this study is the occurrence of a number of macrophages lying on the epithelium of the seminal vesicle. They also are seen to engulf the disintegrated spermatozoa in bulk. The intraluminal macrophages observed may serve to dispose of spermatozoa which have migrated into the seminal vesicle for some unknown reason.

Scanning electron microscopic observation of sperimophage cell within the lumen of the epididymal duct of the vasectomized Japanese monkey (Macacus fuscatus)

The spermiophagic process by intraluminal macrophages in the epididymal ducts of the vasectomized Japanese monkey was well visualized with scanning electron microscope. The fragments of disintegrated spermatozoa were seen in the phase enveloped in bulk by flap-like cytoplasmic extensions or in the phase ingested within the cytoplasm.

Aggressive Behavior in Isolation-reared Adult Japanese Monkeys (Macaca fuscata)

This report was primarily concerned with the comparison of aggressivity in isolation-reared adult Japanese monkeys of various rearing conditions in the pairing experiment with strangers. Results for the males indicate that they were extremely aggressive to strange partners, and that their aggressivity was negatively correlated to the severity of their isolation (Table 1, Fig.1). According to the high frequencies of discreteness between the isolates and their partners (Fig. 2) and the remarkable tendency of the aggressees' withdrawal (Table 2), their aggression may be regarded as repulsive behavior directed to the strangers.Because of the poverty of social experience, the strange partners were more novel for the isolates than for the controls, and so fear produced by the strangers' novelty may be thought as the cause of their aggression. However, the fact that the isolates rarely showed non-defensive aggression when they were subordinate to the partner (Fig. 1) indicates that excessive fear does not result in aggression. In other words, “moderate” level of fear causes aggression. On the other hand, occurrence of aggression also requires “primary” sociability which enables individuals to approach and contact with others, and this appears to be the main reason why the less severely isolated monkeys aggressed more. To summarize above, their aggressivity may be influenced by a level of fear and of “primary” sociability.The isolates lack the more mature form of sociability, that is, “friendly” sociability which can act as an inhibitor of their aggression, and for that reason they showed their aggressivity in a less inhibited fashion.In contrast to the males, the females rarely showed aggressive behavior except F-3 (Fig. 1). The severely isolated females were hyperfearful (Table 2), and the least severely isolated female was even friendly. This can be attributed to sex difference in which females tend to be more friendly, more fearful, and less aggressive than males.

On the Muscular Composition of Lower Extremities of Apes Based on the Relative Weight

Characteristics of the muscular composition of the lower extremities of apes were made clear by comparison of relative weights of the lower extremities among several species of primates including man, and the significance of the characteristics was discussed.As materials, 10 specis, totalling 77 animals, were used: chimpazee, orang-utan, white handed gibbon, great siamang, hanuman langur, dusky lutong, wooly monkey, black spider monkey, Formosan monkey and Japanese monkey.To elucidate intra-species variation, many Japanese monkeys containing fetuses were examined. Adult Japanese monkeys do not show any remarkable individual, bilateral nor sexual differences. The relative weights of hip and thigh regions of fetus and infant are smaller than those of adult. While the relative weights of leg and foot are larger than those of adult. However, the differences in age are smaller than the differences between two species which have different locomotion pattern.In quadrupedal monkey including Japanese monkeys, the relative weight of biceps femoris, which is two joint muscle, is remarkably large, while in man, the bipedalist, biceps femoris is small and gluteus maximus, vastus intermedius, vastus medialis and soleus, which are one joint muscles, are large.As to apes, chimpanzees, gibbons and gorillas have small biceps femoris like man, and their gluteus maximus, vastus medialis and vastus intermedius, which are one joint muscles, are relatively larger than those of quadrupeds. The orang-utan has larger leg and foot muscles than do other species, but the relative weights of their muscles show the medium value between other apes and quadruped monkeys.The above characteristics of muscular compsition of apes are further discussed in comparison with the muscle actions clarified by EMG studies. This revealed that the muscular composition of apes are more similar to that of man which takes erect bipedalism than to that of quadrupeds.

Histological, histochemical and electron microscopic studies on the salivary glands in man and many kinds of animals.

Due to its similarity to the human race, monkey is one of the most important animal for many kinds of experiments. But we have still many problems of inquiry on that animal. For example, there are a few histological and histochemical investigations on the salivary glands of the monkey. Especially, there has been no such investigations on the Japanese monkey. That is why the author has made the following study.Parotid, submandibular and sublingual glands of 4 adult Japanese monkeys were fixed in buffered formalin. The fixed pieces were embedded in paraffin and cut in 6μ thin sections.For the histological studies, the sections were stained with hematoxylin (Mayer)-eosin and azan staining. For the demonstration of neutral polysaccharide, PAS reaction, PAS-dimedon method, saliva test for glycogen, acetylation-PAS reaction, acetylation-saponification-PAS reaction, sulfation-toluidine blue (pH2.5), alcian blue (pH2.2)-PAS reaction were used and the demonstration methods for acid mucopolysaccharides were as follows: aldehyde fuchsin-alcian blue method, alcian blue-safranin method, neutral red method (Sugiyama), Ohno method for differentiation for hyaluronic acid and chondroitin sulfuric acid, alcian blue (pH2.5, pH1.0, pH0.5 pH3.0MgCl20.0-1.0mol), alcian blue (pH3.0 MgCl2 0.0-1.0mol)-PAS reaction, methylation-alcian blue (pH2.2), methylation-saponification-alcian blue (pH2.2).For the demonstration of proteins, the acrolein-Schiff method (P. VAN DUIJN) was tried. The results were as follows:1) The author could hardly find the fat cells in the parotid gland, the submandibular gland and the sublingual gland.2) The so-called serous cells in the sublingual gland are remarkably fewer than the mucous cells, and frequently formed the demilune.3) The acinar cells of the parotid gland are morphologically considered to be the serous cell, but, judging from the histocheinical staining reactions, they contain a very small quantity of neutral mucopolysaccharide, sialomucin and sulfomucin. Therefore, the author considered those cells to be the seromucous cell.4) According to the above-mentioned reasons, the so-called serous cells in the submandibular gland and the sublingual gland were also regarded as the seromucous cells.The reaction of sulfomucin in the serous cells of the sublingual gland were most distinguishable among those cells of the three glands.5) Neutral mucopolysaccaride, sialomucin and sulfomucin were also demonstrated in the mucous cells of the sublingual gland. The reaction of sulfomucin in those cells were pretty remarkable, while, the author could not get clear demonstration of this substance in the mucous cells of the submandibular gland. But the existence of neutral mucopolysaccharide and sialomucin in those cells were proved.6) All kinds of the acinar cells in the three kinds of salivary glands were proved to have no glycogen but protein.

An electron microscopic study on the subcommissural organ of the monkey, Macacus fuscatus.

The subcommissural organ of the adult Japanese red-faced monkey (Macacus fuscatus) was studied by electron microscope.In the ependymal cells of the subcommissural organ two types of secretory substances are demonstrated: one, containing a fine flocculent substance, is light secretory sacs which are derived from the rough-surfaced endoplasmic reticulum located near the perikaryon. The other, filled with homogenously distributed material, is represented by dense secretory granules which are probably produced in the Golgi apparatus through condensation of the content of the rough-surfaced endoplasmic reticulum. Both may be released into the ventricular lumen to form the so-called Reissner fibre (apical secretion).The end-feet of the ependymal cells abutting on the capillaries are characterized by an accumulation of dense bodies of various sizes, some of which can be discerned by acid phosphatase activity. The nature and significance of these dense bodies were discussed in relation to the basal secretion possible in this organ.In the acid phosphatase preparation, the enzyme activity is also present in the Golgi apparatus, lipofuscin granules as well as typical lysosomal particles scattered in the cytoplasm, while the light secretory sacs and the dense secretory granules show little or no reactivity. In the hypendyma located underneath the ependymal cells there are perivascular spaces of varying widths and occasionally secretory hypenymal cells which are similar to the ependymal cells in structure. The capillary endothelial cells frequently contain dense granules resembling dense bodies or dense secretory granules found in the cells of the subcommissural organ.

Morphological studies ofMacaca fuscata: VI. Somatometry

Measurements of various parts of the head and body and weighing the body were carried out on about 170 adult Japanese monkeys (Macaca fuscata) and the results are noted with separate statistics for respective local groups. Intraspecific comparisons in the Japanese monkey and interspecific comparisons in macaques are discussed from the somatometrical point of view. Among macaques, the Japanese monkey has a comparatively large body, a very short tail, relatively wide biacromial and biiliac breadths, and markedly la ge intermembral and intercrural indices. The Japanese monkey itself shows various local variations. The most conspicuous difference is to be found between the so-called Yaku monkey living on Yaku islet (Yakushima), south of Kyushu, and the monkeys living in other parts of Japan, and, therefore, it is understandable that the Yaku monkey has been distinguished as a subspecies (M. f. yakui) of the Japanese monkey. The Yaku monkey has a somewhat small body, a relatively large head, wide hips, and slender hands and feet.

Canine teeth and rank in Japanese monkeys (Macaca fuscata)

Canine teeth were extracted from seven adult male Japanese monkeys. Observations over the next four years led to the conclusion that canines are not essential for either the attainment or maintenance of high rank, but that they may play an important part in the self-defense of low-ranking males.

Histological, histochemical and electron microscopic studies on the salivary glands in man and many kinds of animals

Due to its similarity to the human race, monkey is one of the most important animal for many kinds of experiments. But we have still many problems of inquiry on that animal. For example, there are a few histological and histochemical investigations on the salivary glands of the monkey. Especially, there has been no such investigations on the Japanese monkey. That is why the author has made the following study.Parotid, submandibular and sublingual glands of 4 adult Japanese monkeys were fixed in buffered formalin. The fixed pieces were embedded in paraffin and cut in 6μ thin sections.For the histological studies, the sections were stained with hematoxylin (Mayer)-eosin and azan staining. For the demonstration of neutral polysaccharide, PAS reaction, PAS-dimedon method, saliva test for glycogen, acetylation-PAS reaction, acetylation-saponification-PAS reaction, sulfation-toluidine blue (pH2.5), alcian blue (pH2.2)-PAS reaction were used and the demonstration methods for acid mucopolysaccharides were as follows: aldehyde fuchsin-alcian blue method, alcian blue-safranin method, neutral red method (Sugiyama), Ohno method for differentiation for hyaluronic acid and chondroitin sulfuric acid, alcian blue (pH2.5, pH1.0, pH0.5 pH3.0MgCl20.0-1.0mol), alcian blue (pH3.0 MgCl2 0.0-1.0mol)-PAS reaction, methylation-alcian blue (pH2.2), methylation-saponification-alcian blue (pH2.2).For the demonstration of proteins, the acrolein-Schiff method (P. VAN DUIJN) was tried. The results were as follows:1) The author could hardly find the fat cells in the parotid gland, the submandibular gland and the sublingual gland.2) The so-called serous cells in the sublingual gland are remarkably fewer than the mucous cells, and frequently formed the demilune.3) The acinar cells of the parotid gland are morphologically considered to be the serous cell, but, judging from the histocheinical staining reactions, they contain a very small quantity of neutral mucopolysaccharide, sialomucin and sulfomucin. Therefore, the author considered those cells to be the seromucous cell.4) According to the above-mentioned reasons, the so-called serous cells in the submandibular gland and the sublingual gland were also regarded as the seromucous cells.The reaction of sulfomucin in the serous cells of the sublingual gland were most distinguishable among those cells of the three glands.5) Neutral mucopolysaccaride, sialomucin and sulfomucin were also demonstrated in the mucous cells of the sublingual gland. The reaction of sulfomucin in those cells were pretty remarkable, while, the author could not get clear demonstration of this substance in the mucous cells of the submandibular gland. But the existence of neutral mucopolysaccharide and sialomucin in those cells were proved.6) All kinds of the acinar cells in the three kinds of salivary glands were proved to have no glycogen but protein.

Parental Behavior of Adult Male Japanese Monkeys

Adult male parental behavior, very similar to that originally described by ITANI was observed in a troop of Japanese monkeys living in a large outdoor compound in Oregon. In the Oregon troop: i. Males' social interactions with the young go through two overlapping phases, one before and one after the birth of the year's new babies. Only the dominant males participate in the second phase which involves proximity with mothers and neonates. 2. Adult male Japanese macaque social behavior is strongly seasonal, and variations in male parental behavior are partly a ramification of a more general change in behavior. The view that the males' behavior is a response to distress produced in the young when the mother abandons them upon the birth of a newborn is not upheld by the Oregon data. 3. Male-young affiliative and play interactions are not likely to be an important contribution to the socialization of the young, since at all seasons the overwhelming majority of a young monkey's play and affiliative interactions are with his mother, siblings, and agemates. On the other hand, adult dominant males are responsible for virtually all of the attacks on a neonate under the age of 3 months. This may have an important effect on the social development of the young monkey.