Aspiration pneumonia with adenovirus infection in a Japanese macaque (Macaca fuscata fuscata)

Pneumonia with aspiration of foreign bodies and adenovirus infection was identified in a wild Japanese macaque which died 1 month after capture. The adenovirus infection was considered to be secondary in importance to the pneumonia.     

Sweating in the Japanese macaque (Macaca fuscata)

The sweating rates on the palms and chests of three adult male Japanese macaques were measured by the CaCl₂ method at temperatures of 20–40°C. Rectal and skin temperatures on the palms and chests were also measured by means of copper-constantan thermocouples every minute. As ambient temperature was raised from 20°C to 40°C over a one-hour period, the sweating rates on the palms gradually increased and reached a certain plateau level in 30 to 40 minutes, but the sweating rates on the chests, on the other hand, were very low. A good correlation existed between the skin temperatures and the sweating rates on the palms as well as the skin temperatures and the sweating rates on the chests.     

Development of an anatomically based whole‐body musculoskeletal model of the Japanese macaque (Macaca fuscata)

We constructed a three‐dimensional whole‐body musculoskeletal model of the Japanese macaque (Macaca fuscata) based on computed tomography and dissection of a cadaver. The skeleton was modeled as a chain of 20 bone segments connected by joints. Joint centers and rotational axes were estimated by joint morphology based on joint surface approximation using a quadric function. The path of each muscle was defined by a line segment connecting origin to insertion through an intermediary point if necessary. Mass and fascicle length of each were systematically recorded to calculate physiological cross‐sectional area to estimate the capacity of each muscle to generate force. Using this anatomically accurate model, muscle moment arms and force vectors generated by individual limb muscles at the foot and hand were calculated to computationally predict muscle functions. Furthermore, three‐dimensional whole‐body musculoskeletal kinematics of the Japanese macaque was reconstructed from ordinary video sequences based on this model and a model‐based matching technique. The results showed that the proposed model can successfully reconstruct and visualize anatomically reasonable, natural musculoskeletal motion of the Japanese macaque during quadrupedal/bipedal locomotion, demonstrating the validity and efficacy of the constructed musculoskeletal model. The present biologically relevant model may serve as a useful tool for comprehensive understanding of the design principles of the musculoskeletal system and the control mechanisms for locomotion in the Japanese macaque and other primates. Am J Phys Anthropol, 2009. © 2008 Wiley‐Liss, Inc.     

Hepatic neuroendocrine carcinoma in a Japanese macaque (Macaca fuscata)

Primary neuroendocrine neoplasm of the liver is extremely rare in both humans and non‐human primates. The present report describes the clinical and pathological findings of an aged Japanese macaque (Macaca fuscata) with hepatic neuroendocrine carcinoma. To our knowledge, this is the first report of hepatic neuroendocrine neoplasm in macaques.     

A case of active incomplete biliary cirrhosis in an aged female Japanese macaque (Macaca fuscata)

We describe the first case of biliary cirrhosis in Japanese macaque. Clinical signs had not been detected. The liver was nodular. Histopathologically, portal‐to‐portal pattern of fibrosis might have indicated chronic cholestasis. Fibrotic septa were infiltrated with inflammatory cells. Therefore, this case could be diagnosed as active incomplete biliary cirrhosis.     

Variability of tail length in hybrids of the Japanese macaque (Macaca fuscata) and the Taiwanese macaque (Macaca cyclopis)

In primates, tail length is subject to wide variation, and the tail may even be absent. Tail length varies greatly between each species group of the genus Macaca, which is explained by climatic factors and/or phylogeographic history. Here, tail length variability was studied in hybrids of the Japanese (M. fuscata) and Taiwanese (Macaca cyclopis) macaque, with various degrees of hybridization being evaluated through autosomal allele typing. Relative tail length (percent of crown–rump length) correlated well with the number of caudal vertebrae. Length profiles of caudal vertebrae of hybrids and parent species revealed a common pattern: the length of several proximal-most vertebrae do not differ greatly; then from the third or fourth vertebra, the length rapidly increases and peaks at around the fifth to seventh vertebra; then the length plateaus for several vertebrae and finally shows a gentle decrease. As the number of caudal vertebrae and relative tail length increase, peak vertebral length and lengths of proximal vertebrae also increase, except that of the first vertebra, which only shows a slight increase. Peak vertebral length and the number of caudal vertebrae explained 92?% of the variance in the relative tail length of hybrids. Relative tail length correlated considerably well with the degree of hybridization, with no significant deviation from the regression line being observed. Thus, neither significant heterosis nor hybrid depression occurred.     

Simian immunodeficiency virus infection and flow cytometric characterization of Japanese macaque (Macaca fuscata) hematopoietic cells

We characterized Japanese macaque (Macaca fuscata) hematopoietic cells using flow cytometry and identified 28 cross-reactive anti-human antibody clones. Furthermore, productive infection of peripheral T lymphocytes with simian immunodeficiency virus (SIV) in vitro was confirmed by intracellular SIV p27 staining. This study could facilitate using Japanese macaques as models for human hematological and immunological disorders and infectious diseases.     

Development of co-feeding relationships in immature free-ranging Japanese monkeys (Macaca fuscata fuscata)

The co-feeding relationships of immature Japanese monkeys in the provisioned situation were studied. The most frequent co-feeders for immature females were diversified as compared to those for immature males. The number of immature females who showed strong co-feeding relationships with their mothers gradually decreased with age in both high- and middle/low-ranking matrilines, but the percent decrease was greater for middle/low-ranking immatures. Almost all immature females who displayed strong co-feeding relationships with adult males were from middle/low-ranking matrilines. Strong co-feeding relationships with mothers among immature males from high-ranking matrilines remained until 4 years of age. In contrast, strong co-feeding relationships with mothers among middle/low-ranking immature males decreased rapidly in the first year of life, and most 1- to 4-year-olds showed no strong co-feeding relationships with other group members. It is considered that middle/low-ranking mothers may not provide their immatures with a secure base for obtaining food in the provisioned situation.     

Hypervariable microsatellite loci in the Japanese macaque (Macaca fuscata) conserved in related species

We describe seven polymorphic microsatellites isolated from a Japanese macaque (Macaca fuscata) genomic library selected for (GT)_n content. The primer sets amplified from four to 11 different alleles in a sample of 14 Japanese macaques from nine different sites along the central and southern distribution of the species. These heterologous primers also detected variability in four other cercopithecine species. Am. J. Primatol. 43:357–360, 1997. © 1997 Wiley-Liss, Inc.     

Seroprevalence of Japanese encephalitis virus infection in captive Japanese macaques (Macaca fuscata)

Japanese encephalitis virus (JEV), which is transmitted by mosquitoes, infects many animal species and causes serious acute encephalitis in humans and horses. In this study, a serosurvey of JEV in Japanese macaques (Macaca fuscata) reared in Aichi Prefecture was conducted using purified JEV as an antigen for ELISA. The results revealed that 146 of 332 monkeys (44 %) were seropositive for JEV. In addition, 35 of 131 monkeys (27 %) born in the facility were seropositive, and the annual infection rate in the facility was estimated as 13 %. Our results provide evidence of the frequent exposure of many Japanese macaques to JEV, suggesting that there is a risk of JEV transmission to humans by mosquitoes.     

A further food-washing tradition in Japanese macaques (Macaca fuscata)

A case of food-washing tradition is reported in a captive group of Japanese macaques. Two techniques are employed, with one or both hands being used to wash food under water flowing from watering spouts. Processes of diffusion of the behaviour in the group follow the patterns previously described by Japanese scientists observing this species. It is suggested that development of such a behaviour could be related to particular environmental conditions.     

A preliminary study on hair length in the Japanese monkey (Macaca fuscata fuscata)

The hair length of Japanese monkeys was investigated. The hair of the Japanese monkey is long on the back and the lateral side of the upper arm and short on the back of the hand. There was variation in the length of hairs in the same region of the body. The distribution of hair length approximated to a normal curve and did not display any marked bias or skewness. The increase in length of hairs was remarkable from 0 to 1 year of age, and then continued at a constant rate. Sex differences in hair length were not so remarkable at any age.     

Self-wrist biting in Arashiyama-B troop of Japanese monkeys (Macaca fuscata fuscata)

Self-wrist biting in the Arashiyama-B troop of Japanese monkeys was observed during a nearly 4-year study. In all, six monkeys were seen performing this behavioural pattern. Medium ranking monkeys belonging to the age class 2–7 years performed this behavioural pattern most frequently. A slight tendency for the diffusion of this behaviour along kinship lines was also observed.     

Annual changes in hair length of the Japanese monkey (Macaca fuscata fuscata)

The hair length of Japanese monkeys was investigated for a period of one year and the molting phenomenon was clarified. Nine monkeys were employed in the study. The molting of the Japanese monkey was found to be of a seasonal type and occurred once during the year. The molting continued for one to four months in each monkey. The hair of the Japanese monkeys was wholly replaced during the period from April to August. The hair length was thus short in summer, and long in winter. Hair replacement in pregnant females began after parturition and was generally later than that in other individuals. During molting, both new and old hairs could be observed simultaneously in the same region of the body. The hair replacement ended around summer when the hair became the shortest. The new hairs continued to grow after molting and became the longest towards autumn or winter. Thus, the summer coat and the winter coat were essentially the same in the Japanese monkey. Such annual changes in the hair of the Japanese monkey were considered to be suitable for the climate of Japan.