Atrial Septal Defect in a Bonnet Macaque (Macaca radiata)

Atrial Septal Defect was detected at autopsy in a subadult bonnet macaque (Macaca radiata). Case history and autopsy findings were described.     

Snake Species Discrimination by Wild Bonnet Macaques (Macaca radiata)

Wild bonnet macaques (Macaca radiata) were studied in southern India to assess their ability to discriminate non‐venomous, venomous and predatory snakes. Realistic snake models were presented to eight troops of bonnet macaques at feeding stations and their behavior was video‐recorded 3 min before and 3 min after snake exposure. Snakes presented were: (1) venomous Indian cobra (Naja naja) displaying an open hood with ‘eyespots’; (2) venomous common Indian krait (Bungarus caeruleus); (3) non‐venomous green keelback (Macropisthodan plumbicolor); (4) non‐venomous rat snake (Ptyas mucosus); and (5) Indian python (Python molurus) which preys on macaques. Latencies to detect and react to the snakes were evaluated to determine initial responsiveness. Longer‐term assessment was measured as the percentage of time individuals looked at the snakes and monitored the activity of nearby individuals before and after snake detection. All snake models engendered caution and maintenance of a safe distance. Alarm calling occurred only during python presentations. The cobra engendered a startle response or running in the largest percentage of individuals after its detection, whereas the rat snake and python elicited bipedal standing or ambulating to monitor the snakes. We also examined the influence of age on snake recognition. Juveniles and subadults looked at the cobra, krait, and python for a larger percentage of time than adults did; albeit, adults looked at the python substantially longer than at the other snakes. Age differences in behavior suggest that, with the exception of the python, repeated experience with snakes in the wild moderates excitability, consistent with the likely threat of envenomation.     

Birth Patterns in Wild and Captive Lion-Tailed Macaques (Macaca silenus)

During a 5-yr study of lion-tailed macaques in their natural habitat, we found that: 1) most births occurred from January to April (70%) and from September to December (19%), showing a bimodal pattern with a major and a minor birth peak; 2) the period of peaks remained the same over 5 yr; and 3) a similar pattern of birth peaks occurred both in groups in large forest complexes that had overlapping home ranges with other groups and in single groups that were isolated in forest fragments in the same region but with similar ecological conditions. The results suggest more of a birth seasonality than mere breeding synchronization in the wild lion-tailed macaques. We also analyzed data on births in captivity in European Zoos for 10 yr. We observed no seasonality or peaks in births, and the pattern was the same over the years. Data on rainfall suggest that resource availability in the wild habitat may not be uniform throughout the year; hence, ecological factors may play an important role in determination of birth patterns in the natural habitats of lion-tailed macaques.     

Infant Survival Among Free-Living Bonnet Macaques (Macaca radiata) in South India

International Journal of Primatology - Female reproductive success depends to a large extent on infants’ ability to survive to maturity. While most studies of female reproductive success have...     

Age Differences in the Responses to Adult and Juvenile Alarm Calls by Bonnet Macaques (Macaca radiata)

This study examined the differential responses to alarm calls from juvenile and adult wild bonnet macaques ( Macaca radiata ) in two parks in southern India. Field studies of several mammalian species have reported that the alarm vocalizations of immature individuals are often treated by perceivers as less provocative than those of adults. This study documents such differences in response using field-recorded playbacks of juvenile and adult alarm vocalizations. To validate the use of playback vocalizations as proxies of natural calls, we compared the responses of bonnet macaques to playbacks of alarm vocalizations with responses engendered by natural alarm vocalizations. We found that the frequency of flight, latency to flee, and the frequency of scanning to vocalization playbacks and natural vocalizations were comparable, thus supporting the use of playbacks to compare the effects of adult and juvenile calls. Our results showed that adult alarm calls were more provocative than juvenile alarm calls, inducing greater frequencies of flight with faster reaction times. Conversely, juvenile alarm calls were more likely to engender scanning by adults, a result interpreted as reflecting the lack of reliability of juvenile calls. Finally, we found age differences in flight behavior to juvenile alarm calls and to playbacks of motorcycle engine sounds, with juveniles and subadults more likely to flee than adults after hearing such sounds. These findings might reflect an increased vulnerability to predators or a lack of experience in young bonnet macaques.     

Studies on ovarian quiescence in the lactating bonnet monkey (Macaca radiata)

Lactating bonnet monkeys were used as a model to understand the mechanism of ovarian quiescence during lactation. The ovary of the bonnet monkey in the 3rd month of lactation responds well to exogenous pregnant mare serum gonadotropin stimulation with serum estrogen values reaching maximal levels by day 3 of the gonadotropin injection. The adminstration of ovine prolactin to such monkeys significantly inhibited the ovarian responsiveness to exogenous gonadotropin. The responsiveness of the pituitary of the lactating monkey (in the 3rd month of lactation) to luteinizing hormone releasing hormone injection was suppressed and supplementation with exogenous prolactin further accentuating this effect. The relative ability of chlorpromazine given intravenously/intramuscularly/intranasally to enhance endogenous prolactin levels was assessed. During the first 5 months of lactation when the basal prolactin levels were high, the luteinizing hormone levels were low. As the suckling stimulus reduces and prolactin levels fall, luteinizing hormone levels increase, the first post-parturient mensus occurring by 218 ± 4 days. This event was postponed by 3 months on increasing endogenous prolactin levels by administering chlorpromazine (250 μg/day by intranasal mode) over a 5 day period every month starting from the 3rd month of lactation.     

Differential Probability of “Coproduction” in Two Species of Macaque (Macaca tonkeana,M. mulatta)

This study aimed to assess the conditions under which monkeys might produce common effects in an instrumental task. One group of Tonkean macaques (Macaca tonkeana) and two groups of rhesus macaques (M. mulatta) were given series of tests in which food incentives were placed under stones of various weights. In the Tonkean group, the simultaneous action of two subjects in moving the same stone was a relatively frequently occurring event: coaction was more effective than individual action for moving heavy stones; however, there were no signs of coordination among partners and no improvement through learning. In rhesus groups, instances of coaction were extremely rare, and rates of agonistic interactions were higher than in the Tonkean group. It is suggested that “coproduction” represented an emergent phenomenon resulting from social interactions and, as such, was dependent on the level of interindividual tolerance.     

An ethogram of the liontail macaque (Macaca silenus) in captivity

Seventy hours of observation were gathered on a well-composed group of captive liontail macaques (1 adult male, 3 adult females, 1 sub-adult male, 1 sub-adult female, 2 juvenile males, 1 infant male, and 2 infant females caged together for more than five years). Their behaviors are described, defined and categorized, and comparisons are made with other Macaca species. Most of the behaviors observed tended to be similar to those of other congeneric macaques, with the exception of several variations typical for the liontail which are detailed. The behaviors and interactions of infant liontail monkeys are also discussed.     

Time budget and activity patterns of the lion-tailed macaque (Macaca silenus)

We studied time budgeting of lion-tailed macaques in the Anamalai Wildlife Sanctuary, Tamil Nadu, India, with regard to seven activity categories. Groups spent >50% of their time feeding and foraging, 33% of the time resting, and 15% moving. More energetic activities were spread uniformly through the day. Feeding had two annual peaks: one closely following the northeast monsoon and the other corresponding to the southwest monsoon. These also coincided with peaks of food availability and mating. Time saved in feeding was spent mostly on resting. Ranging showed a pattern contrary to that of time spent moving and was related more to weather than to food availability; it increased during cooler periods. The middle and upper stories of the canopy were used >93% of the time. The ground was used rarely. Time budgeting characteristics of the lion-tailed macaque are primarily frugiinsectivorous adaptations to a wet evergreen forest habitat.     

Threat-Related Acoustical Differences in Alarm Calls by Wild Bonnet Macaques (Macaca radiata) Elicited by Python and Leopard Models

Wild and urban bonnet macaques (Macaca radiata) were studied in southern India to record alarm calls during presentations of realistic models of spotted and dark leopards (Panthera pardus) and an Indian python (Python molurus). Recordings of alarm calls were made from members of four forest troops at feeding stations who observed brief and prolonged presentations of fully exposed spotted and dark leopard morphs and partially concealed views of the spotted morph. Four different forest troops were presented a slowly moving python near feeding stations. Two predator‐inexperienced urban troops from the city of Bangalore were presented either the spotted leopard morph briefly or the python. Analyses of alarm calls revealed differences in acoustic structure, such as a lower harmonic to noise ratio, which can be interpreted as reflecting the level of perceived threat rather than predator type. Noisy alarm calls likely indicate high states of physiological arousal that might provide eavesdropping troop members with information useful for assessing the urgency of the predatory threat. Lack of alarm‐call distinctiveness characterizing predator type is complemented by explicit contextual information in which alarm calling to leopards never occurred on the ground whereas nearly all initial python‐elicited alarm calls were made by individuals on the ground monitoring the python. The alarm calls of Bangalore monkeys distinguished the leopard and python models, with the latter engendering the noisiest calls and immediate flight to trees. Such flight is unnecessary with the python and suggests that, without appropriate experience with pythons, bonnet macaques adopt less predator specific refuge‐seeking behavior.     

Brief communication: Morphometric data for adult lion-tailed macaques (Macaca silenus)

Basic morphometric data were collected from 22 adult lion-tailed macaques (M. silenus) of both sexes. M. silenus is a rare primate species from which adequate morphometric data have not heretofore been available for comparative purposes. Data collected include measures of gross body size (weight; crown-rump and rump-heel length), and for males, measures of secondary sexual characteristics (canine tooth and testes size). Degree of sexual dimorphism was marked, with males significantly larger and heavier than females. The three body size measures were correlated for males but not for females. There was substantial variation among individual males in secondary sex characteristics measurements. The data indicate than lion-tailed macaque morphometrics are consonant with the general pattern of positive allometry for body size and sexual dimorphism characteristic of the primate order.     

Species differences in the interest shown in infants by juvenile female macaques (Macaca radiata andM. mulatta)

Using a focal animal technique, 16 juvenile female rhesus and bonnet macaques (2–3 years old) were observed with respect to the frequency and duration of their contacts with infants (0–1 year old). Each of these subjects was a member of one of four seminatural groups of macaques housed in 0.5-acre field cages at the California Primate Research Center. Rhesus juvenile females became very interested in infants when the latter were quite young, and maintained that interest throughout the study. When the infants were approximately 3–4 months old, the rhesus juveniles spent, on the average, 3.9 min/hr with those infants. By the time the infants were yearlings, the time spent with infants was approximately 6 min/hr. Relative to the rhesus, the bonnet juveniles showed less interest (about 2.2 min/hr) in young (3- to 4- month-old) infants, although by the time the infants were yearlings, the bonnets spent about 5.6 min/hr with them. Rhesus juveniles preferred sibling over nonsibling infants, but the presence of a sibling was not a necessary requirement for infant-directed behavior. The two bonnet juveniles who had infant siblings showed no preference for the latter. These data were interpreted within the framework of Quiatt’s [(1979) Am. Anthropol. 81: 310–319 conclusions about allomaternal behavior. Specifically, it was argued that, to the extent that there are species differences in maternal behavior, there should also be species differences in allomaternal behavior. The species differences in the maternal styles of rhesus and bonnet macaques provide a basis for an examination of this hypothesis.     

Viable spermatozoa in the bladder after electroejaculation of lion-tailed macaques (Macaca silenus)

The bladder of 6 lion-tailed macaques was emptied and flushed with sterile saline. TALP-Hepes buffer was infused and the animals were electroejaculated. After electroejaculation, the semen quality was determined in the ejaculate and the bladder infusate. Of the 15 ejaculates analysed, a mean (+/- s.e.m.) sperm count of 133.8 (+/- 30.7) x 10(6) with 69.5 (+/- 6.0)% motility was obtained in the infusate as compared to the sperm count of 72.4 (+/- 38.6) x 10(6) with significantly lower (47.7 +/- 5.8%) motility in the ejaculate.     

MamuSNP: a resource for Rhesus Macaque (Macaca mulatta) genomics

We developed a novel method for identifying SNPs widely distributed throughout the coding and non-coding regions of a genome. The method uses large-scale parallel pyrosequencing technology in combination with bioinformatics tools. We used this method to generate approximately 23,000 candidate SNPs throughout the Macaca mulatta genome. We estimate that over 60% of the SNPs will be of high frequency and useful for mapping QTLs, genetic management, and studies of individual relatedness, whereas other less frequent SNPs may be useful as population specific markers for ancestry identification. We have created a web resource called MamuSNP to view the SNPs and associated information online. This resource will also be useful for researchers using a wide variety of Macaca species in their research.     

Sex Differences and Age Gradations in Vocalizations of Japanese and Lion-tailed Monkeys (Macaca fuscata and Macaca silenus)

SYNOPSIS. Vocal repertoires of male and female non-human primatescan differ by presenceor absence of sounds, acoustic form, andfunction or usage. Examples of sex-specificity in vocalizationsare taken from field studies of two macaque species that differin social organizationand habitat. They are used to illustratesex-specific acoustic patterns and vocalizations thatare employedin socially different fashion by males and females. Some vocalsex differences develop from sounds shared in common by younganimals of both sexes while others arise late in life by anacoustic pattern suddenly emerging only in males. Differencesmay be due to sexual selection, social suppression, morphologicalfeatures, or because vocal sounds are linked to circumstancesexperienced by only male or female adults. The relation betweensocial usage of some vocalizations by adults and youngstersaffords insights into their signal value and into the underlyingstate of the vocalizing animal.     

Manipulation of objects in a captive group of lion-tailed macaques (Macaca silenus)

The purpose of this study was to investigate the manipulative propensities of a captive group of lion-tailed macaques (Macaca silenus). Simple natural objects (browse and bamboo poles) were provided regularly in the home cage. Findings indicate richness in the frequency and form of manipulative activities, with juvenile males manipulating the test objects more frequently and exhibiting more goal-directed manipulative activity than adult females. A variety of goal-directed manipulative activities (use of objects to act as ladders, to apply leverage, and to create perches) occurred spontaneously, with some instances involving joint action or social use. These data are consistent with the hypotheses that macaques possess extensive capacities for object exploration and social facilitation, and that an evolutionary history of omnivorous foraging habits correlates positively with the expression of anomalous sensorimotor skills.     

Evaluation of rabies virus neutralizing antibody titres induced by intramuscular inoculation of rabies DNA vaccine in mice and Bonnet monkeys (Macaca radiata)

A rabies DNA vaccine consisting of plasmid DNA expressing the rabies virus surface glycoprotein was injected (im) twice at two week interval to outbred swiss mice or Bonnet monkeys (Macaca radiata) and the levels of rabies virus neutralizing antibody (VNA) titres were examined over a one year period. In mice, the VNA titre was maintained above the minimum protective level (0.5 I.U./ml) up to 10 months after primary immunization, while in monkeys, the titre dropped below the protective level by 6 months. An anamnestic B cell response was seen in both mice and monkeys following the administration of a booster dose, 10 and 6 months after the primary immunization, respectively. These results indicate that im injection of rabies DNA vaccine induces VNA in nonhuman primates and mice unlike intradermal (id) immunization, which was shown to induce VNA only in mice but not in monkeys. This is the first report on the induction of VNA in nonhuman primates by im inoculation of rabies DNA vaccine.