A simple technique for investigating gut passage times in small New World primates was developed, which produced good results without any need for special housing or diet, or for the separation of monkeys from their groups. This technique, which allowed the administration of a faecal marker, chromium oxide, to specific individuals, was used to investigate gut passage times in five species of the genera Callithrix, Saguinus, Leontopithecus and Callimico. Overall, average gut passage time was 4.5 hours, and there were no species differences. Such nondisruptive methods could help in assessing the effects of dietary changes in captive monkeys, and therefore be of considerable value in improving captive diets and hence welfare and breeding success.

Electronic microchip implants were used to identify groups of crab-eating (Macaca fascicularis) and rhesus (Macaca mulatta) macaques. They were implanted in different body sites and monitored for up to fifteen months. One group of rhesus macaques was trained to present the wrist in which the microchip was placed, to enable it to be read easily with the scanner. An improved method of permanently identifying primates will lead to better record keeping and could benefit the animals’ welfare.

Vervet monkeys (Chlorocebus pygerythrus) encounter a plethora of anthropogenic risks as a result of their ability to exploit humanaltered environments. A systematic assessment of these risks has not been carried out to date. Here, we aim to begin addressing this gap in our understanding of human-vervet conflict in South Africa. We present a descriptive analysis of the intake of the Vervet Monkey Foundation (VMF) — a specialist vervet monkey rehabilitation centre and sanctuary in the Limpopo Province. Between October 2003 and March 2012 almost 200 vervet monkeys arrived at the VMF. At least 161 infants arrived with a steady decrease in annual intake over time, most probably due to the increasing number of other centres in the province. Detailed data for all age classes were available from March 2009 to March 2012. Of the 50 monkeys that arrived during this period, more young monkeys (infants and juveniles) than adults arrived and more infants than juveniles. Intake of injured and uninjured monkeys was equal. The majority of injuries were caused by cars and the majority of uninjured arrivals were ex-pets handed over voluntarily. A distinct temporal pattern of arrival, peaking in the austral summer, coincides with the birthing season of vervet monkeys in South Africa. The merits of publishing such records and the welfare implications of the perceptions of and objections to these ‘pest’ primates are discussed.

For management and/or research purposes, chimpanzee mothers and their offspring are often physically separated from one another at an earlier age than they would be in the wild. Studies of the behavioural and physiological effects of mother-infant separation on infant behaviour have been conducted in both human and nonhuman primates. However, few studies have been conducted to examine the response of the mother to separation from her infant, particularly in great apes. The current study opportunistically examined the response of twelve chimpanzee mothers to separation from 15 of their offspring ranging from 1.8 to 5.4 years of age. Behavioural data (proximity of the mother to other group members, and fifteen behaviours representing six categories [agonistic, prosocial, vocalisations, abnormal, locomotor, inactive]) were collected for three weeks prior to and three to five weeks following the permanent removal of the offspring from their mothers. A repeated measures MANOVA conducted on all subjects revealed no significant change in behaviour following separation. There was a significant increase in inactivity following separation of the offspring (F2.21 = 5.47, P < 0.05) in a subgroup of mothers (n = 8) that was studied more intensively on the first day of separation. Maternal age, infant age, presence of other offspring, and past experience with mother-offspring separation had no effect on response to separation. These results contradict those of mother-infant separation studies in monkeys and indicate that most behavioural indicators of well-being are stable in chimpanzee mothers that remain in their familiar environment and social group following offspring separation.

Aggression and agonism typically accompany the initial interactions exchanged between unfamiliar primates. As a part of a larger study examining the social function of scrotal colour in vervet monkeys (Cercopithecus aethiops sabaeus), this paper offers experimental data to show how scrotal colour can influence aggression, and how artificial colour treatment can be used as an effective tool for managing aggression. Study animals were 81 vervet monkey pairs composed of 162 similarly-sized, unfamiliar adult males originating from non-adjacent parishes in Barbados. Non-contact and contact aggression were recorded on a continuous basis during 90 minute introductions. The main effects of the Test male scrotal colour, Stimulus male colour, and the interaction of the Test male and Stimulus male colours were not significant predictors of non-contact aggression. The effects of scrotal colouration of the Test male and Stimulus male were not significant predictors of contact aggression either, but there was a significant interaction effect; pairs of males with similar scrotal colour engaged in contact aggression more often than pairs of males differing in colour. Painting the scrotum dark led to more aggression when these males were paired with dark coloured males and less aggression when these males were paired with pale coloured males. These findings suggest a practical and inexpensive means of reducing the likelihood of aggression when introducing new animals. These results may also be applicable for other taxa that have colourful sexual skin, such as mandrills, drills, talapoins, patas monkeys, and many guenon species.

Russell and Burch's Three Rs (replacement, reduction and refinement) remain the cornerstone for principles guiding humane experimental research. However, the concept of refinement has evolved considerably since its first inception and there have been numerous interpretations, some of which are regressive from the original definition. In this paper we examine the interpretations of refinement, and propose a harmonised progressive definition that is in line with changes in animal ethics and animal welfare science. Our definition should be applied to all aspects of refinement: those related to housing, husbandry and care, techniques used in scientific procedures, periprocedural care, health and welfare monitoring, and experimental design. We argue not only that the concept should include the avoidance or minimisation of adverse effects experienced at any time during the life of an animal destined for use in a laboratory, but also that it should be applied to the founder animals. Furthermore, we take a proactive stance and argue that refinement should include enhancing well-being through environmental enrichment. The acceptance and application of this new definition by legislative authorities and in guidelines would represent a significant step forward for animal welfare.

Refinement of social housing practices is paramount to improving animal welfare in laboratory environments, especially with regard to non-human primates. Even though social housing of the same species should be considered the optimal paradigm, cynomolgus (Macaca fascicularis) and rhesus macaques (Macaca mulatta) share similar communication styles making inter-species, opposite sex socialisation a viable approach to providing social enrichment. This paper describes social housing a male cynomolgus macaque, which underwent a routine orchiectomy prior to pairing, with a female rhesus macaque for the purpose of providing social interaction for animals that otherwise would have been single housed. Once paired, the primates exhibited behaviours indicative of compatibility, including mounting, lip smacking, grooming, co-threatening and choosing to remain in close proximity. Social housing also ameliorated abnormal behaviour (eg pacing, self-directed fur-plucking) in the female macaque. Neutering male macaques, mixed-species pairing and opposite sex socialisation are all valid options for reducing the number of individually housed primates in research facilities.

It has been suggested that housing of laboratory primates in two-tiered racks adversely affects the psychological well-being of those primates housed on the lower row. Excessive darkness and its consequences are among the factors suggested to account for the supposed diminished well-being of lower-row inhabitants. Additionally, two-tiered housing has been suggested to introduce unacceptable variation into experimental designs, potentially necessitating additional subjects and/or invalidating results. Only recently have data been published to address these issues, but all studies have involved small numbers of subjects. In the present study, we compared the behaviour of 45 yearling rhesus macaques (Macaca mulatta) housed in upper-row cages with the behaviour of 48 yearling rhesus macaques housed in lower-row cages during a year of single housing. There were no significant differences across cage locations for time spent performing behaviours indicative of diminished psychological well-being (abnormal behaviour, inactivity, vocalisation, self-directed grooming) or for species-typical activities (feeding, playing). The difference in time spent exploring between macaques housed on the lower row and those housed on the upper row approached significance, with lower-row-housed animals spending more time exploring. Although lower-row cages are significantly darker than upper-row cages at our facility, the data from the present study demonstrate that the diminished lighting and other supposed disadvantages experienced by lower-row-housed monkeys have few behavioural consequences. Thus, there are now additional empirical data that suggest that lower-row-housed monkeys are not suffering in a “monkey cave”, and that the findings of research projects using two-tiered housing systems are unlikely to be compromised.

It has been suggested that providing multiple computers with automatic reward dispensers as enrichment to captive orangutans (Pongo spp) (as opposed to a single computer, with a care-staff person delivering reinforcers) might help improve behavioural outcomes. The purpose of the current study was to test this hypothesis by providing two computers with automatic reward dispensers to eight orangutans housed in four male-female pairs at Zoo Atlanta, USA. Subjects were observed for ten days during each of three phases: a baseline phase (during which, no computer was provided); immediately followed by Phase 1 (during which, one computer system was provided to each pair of subjects); immediately followed by Phase 2 (during which, two computer systems were provided to each pair). Data were collected in 1-h sessions using instantaneous scan sampling. There was no habituation to the computer system, nor were there any significant increases in aggression, rough scratching, and abnormal behaviours in either computer phase, which indicates that computer-joystick systems are effective as enrichment for captive orangutans. However, a high level of interest in the computer was shown by only a few individuals, which highlights a need to take into consideration individual differences when providing computerised enrichment to captive non-human primates. It would also be advisable to provide other forms of enrichment to increase activity levels for individuals which are not interested in interacting with a computer, as well as to help increase the diversity of behaviours being stimulated by the enrichment.

Chimpanzees (Pan troglodytes) that are kept in captivity come from a wide variety of backgrounds, and a proportion of them have been subjected to maternal separation and social deprivation during development. The long-term effects of such practices have received little investigation. This study investigates whether the removal of infants from their mothers and/or other chimpanzees affects their activity levels and abnormal behaviours later in life. A total of 69 resocialised chimpanzees were studied at six zoos in the United Kingdom. Chimpanzees were categorised into one of three rearing conditions: reared by their mother in a group of conspecifics (MGR); reared with other conspecifics but separated from their mothers (RO); and reared apart from their mother or other conspecifics for a period of time during infancy (RA). Results indicate that ‘socially deprived’ individuals show reduced levels of normal activity, elevated levels of abnormal behaviours and a wider repertoire of abnormal behaviours. These differences were more pronounced in younger individuals, with adults from the three different rearing conditions performing abnormal behaviour patterns at comparable levels. It is concluded that human-rearing, either alone or with conspecifics, influences behaviour through suppression of normal activity levels as a result of separation and elevation of levels of abnormal behaviours as a mechanism for coping with maternal loss and restricted rearing. However, these effects are not irreversible and recovery of ‘normal’ behaviours may occur with access to an enriched social environment.

Chronic pain and distress are universally accepted conditions that may adversely affect an animal's quality of life (QOL) and lead to the humane euthanasia of an animal. At most research institutions and zoological parks in the USA, a veterinarian, who has physically examined the animal and reviewed the clinical records, ultimately decides when an animal has reached a humane endpoint. To aid in the difficult process of interpreting pain and distress, we have developed specific behavioural guidelines, in addition to standard clinical information, to help define unique characteristics and traits of primates to assess and promote discussion of an individual primate's QOL, and thereby, to assist in the decision-making process regarding euthanasia. These guidelines advocate the creation of a QOL team when the animal is diagnosed with a life-threatening or debilitating chronic condition, or at the time the animal is entered into a terminal study. The team compiles a list of characteristics unique to that individual animal by utilising a questionnaire and a behavioural ethogram. This list enables the team to quantitatively assess any deviations from the established normal behavioural repertoire of that individual. Concurrently, the QOL team determines the number of behavioural deviations that are needed to trigger an immediate discussion of the necessity for humane euthanasia of the animal. The team remains intact once created, and revisits the animal's condition as frequently as deemed necessary. This process improves animal welfare by continuing the quest to optimally define QOL for captive primates, and potentially for all captive animals.

The study of environmental enrichment has identified a variety of effective forms of enrichment, but there are widespread problems associated with their use. Few forms of enrichment are cognitively challenging, and even the most effective often result in rapid habituation. This study examined the use of a computer-joystick system, designed to increase in complexity with learning, as a potential form of enrichment. Eight orangutans (Pongo pygmaeus), housed in male/female pairs, were observed for 120 h during a baseline period and 120h when the computer-joystick apparatus was available. Data were collected in 1 h sessions using instantaneous group scan sampling with 30 s intervals. The orangutans spent 25.9% of the scans using the joystick system. One member of each pair monopolised the computer system: ‘high users’ spent 48.9% of scans using the joystick system compared with 2.9% by ‘low users’. Behavioural changes associated with the provision of the computer included increases in aggressive behaviour, anxiety-related behaviours, solitary play, contact with and proximity to a social partner, and decreases in feeding. The lack of habituation by the high users, both within and across sessions, indicates that computer-assisted tasks may be a useful form of environmental enrichment for orangutans. However, the significant increase in aggression indicates that this form of enrichment may be more suitable for singly caged animals, or that the provision of multiple apparatuses should be tested for the ability to eliminate potential competition over the device.

The focus of wildlife rehabilitation is the survival of the individual animal, often leading to rehabilitators being in conflict with government wildlife officials, who regulate the industry and whose focus is on the security of entire wildlife communities. In South Africa, wildlife rehabilitation has been the focus of recent attention from the general public, government and academics, due mostly to the development and adoption of norms and standards for the management of primates. Our study was initiated to provide the first survey of rehabilitation centres in South Africa. Questionnaires were returned by 65% known rehabilitation centres in South Africa, including all nine Provinces, through which several thousand injured, diseased and orphaned animals pass each year. It is clear there is a need for rehabilitation centres in South Africa. However, due to a lack of scientific research on the efficacy of rehabilitation methods for care and release, and minimal post-release monitoring, wildlife rehabilitation techniques and protocols have been based on work experience and subjective intuition. In conjunction with a lack of funds, there may be negative impacts on individual animal welfare and survival, as well as on conservation efforts for wildlife communities. Similar issues have been documented in other regions of the world. In the authors’ opinion, centralisation of wildlife rehabilitation to national or provincial government is a necessity. Furthermore, it is suggested that guidelines of minimum standards should be developed in consultation with experienced rehabilitators, veterinarians and conservation scientists; to be enforced by trained and dedicated conservation officials.

The welfare of zoo animals depends on a combination of physical, social, dietary and other ecological characteristics of the captive setting. We analysed the influence of the transfer of an adult couple of hamadryas baboons (Papio hamadryas) from a small and non-enriched cage that was closed to the public to a larger and enriched exhibit at the visitation area of the Sapucaia do Sul Zoological Park, RS, Brazil. A total of 350 h divided into four stages were spent observing the baboons: (i) in the non-enriched enclosure before the transfer; (ii) soon after the transfer to the enriched enclosure; (iii) six months; and (iv) 12 months after the transfer. The occurrence of stereotypic, social aggressive and social affiliative behaviours was recorded by ‘all occurrences’ sampling. The female showed a decrease in frequency of a stereotypic behaviour (spinning) and an increase in grooming in the enriched enclosure. The male showed a decrease in the frequency of certain stress-related or stereotypic behaviours after transfer, but other stress-related behaviours either increased or remained constant. The male behaviour of throwing faeces was affected by the presence of visitors. We suggest that the well-being of the female was more positively influenced by the new enclosure than that of the male, although gender differences may reflect the normal behavioural repertoire of this sexually dimorphic species.