Testing the Effect of Medical Positive Reinforcement Training on Salivary Cortisol Levels in Bonobos and Orangutans

The management of captive animals has been improved by the establishment of positive reinforcement training as a tool to facilitate interactions between caretakers and animals. In great apes, positive reinforcement training has also been used to train individuals to participate in simple medical procedures to monitor physical health. One aim of positive reinforcement training is to establish a relaxed atmosphere for situations that, without training, might be very stressful. This is especially true for simple medical procedures that can require animals to engage in behaviours that are unusual or use unfamiliar medical devices that can be upsetting. Therefore, one cannot exclude the possibility that the training itself is a source of stress. In this study, we explored the effects of medical positive reinforcement training on salivary cortisol in two groups of captive ape species, orangutans and bonobos, which were familiar to this procedure. Furthermore, we successfully biologically validated the salivary cortisol assay, which had already been validated for bonobos, for orangutans. For the biological validation, we found that cortisol levels in orangutan saliva collected during baseline conditions were lower than in samples collected during three periods that were potentially stressful for the animals. However, we did not find significant changes in salivary cortisol during medical positive reinforcement training for either bonobos or orangutans. Therefore, for bonobos and orangutans with previous exposure to medical PRT, the procedure is not stressful. Thus, medical PRT provides a helpful tool for the captive management of the two species.     

Factors Influencing the Well-Being and Longevity of Captive Female Orangutans

I examined factors affecting the health and mortality of female orangutans in captivity and identified specific aspects of husbandry that appear to be critical to long-term survival in captivity. There are certain high-hazard events in the life of a captive female orangutan, including birth and parturition. Other than the short periods of high hazard, and perhaps of more significance to long-term survival, the major factors that appeared to influence long-term health and mortality included primiparous age, interbirth interval, rearing type, and weight.     

Food Preferences and Nutrient Composition in Captive Spider Monkeys,Ateles geoffroyi

We assessed the occurrence of food preferences in captive spider monkeys and analyzed whether their preferences correlate with nutrient composition. Using a two-alternative choice test, we repeatedly presented 7 Ateles geoffroyi with all possible binary combinations of 12 types of food that are part of their diet in captivity. They exhibited the following rank order of preference: avocado > sapodilla > pineapple > mango > papaya > melon > banana > apple > tomato > orange > carrot > cucumber. Correlational analyses revealed that this preference ranking is significantly positively correlated with total energy content, irrespective of the source of energy as neither total carbohydrate content nor protein or lipid content is significantly correlated with food preference. Further, food preferences are significantly negatively correlated with water content and positively correlated with the content of magnesium, copper and manganese. These results suggest that despite their high degree of frugivory and high taste sensitivity for soluble carbohydrates, spider monkeys are opportunistic feeders with regard to maximizing net gain of energy.     

Positive Reinforcement Training in Squirrel Monkeys Using Clicker Training

Nonhuman primates in research environments experience regular stressors that have the potential to alter physiology and brain function, which in turn can confound some types of research studies. Operant conditioning techniques such as positive reinforcement training (PRT), which teaches animals to voluntarily perform desired behaviors, can be applied to improve behavior and reactivity. PRT has been used to train rhesus macaques, marmosets, and several other nonhuman primate species. To our knowledge, the method has yet to be used to train squirrel monkeys to perform complex tasks. Accordingly, we sought to establish whether PRT, utilizing a hand‐box clicker (which emits a click sound that acts as the conditioned reinforcer), could be used to train adult male squirrel monkeys (Saimiri boliviensis, N = 14). We developed and implemented a training regimen to elicit voluntary participation in routine husbandry, animal transport, and injection procedures. Our secondary goal was to quantify the training time needed to achieve positive results. Squirrel monkeys readily learned the connection between the conditioned reinforcer (the clicker) and the positive reinforcer (food). They rapidly developed proficiency on four tasks of increasing difficulty: target touching, hand sitting, restraint training, and injection training. All subjects mastered target touching behavior within 2 weeks. Ten of 14 subjects (71%) mastered all tasks in 59.2 ± 2.6 days (range: 50–70 days). In trained subjects, it now takes about 1.25 min per monkey to weigh and administer an intramuscular injection, one‐third of the time it took before training. From these data, we conclude that clicker box PRT can be successfully learned by a majority of squirrel monkeys within 2 months and that trained subjects can be managed more efficiently. These findings warrant future studies to determine whether PRT may be useful in reducing stress‐induced experimental confounds in studies involving squirrel monkeys. Am. J. Primatol. 74:712–720, 2012. © 2012 Wiley Periodicals, Inc.     

Familiarity During Immaturity: Implications for the Captive Propagation of Gibbons

Immature captive gibbons are often housed together to facilitate healthy social development. Zoo personnel have wondered if the familiarity acquired during peer-rearing results in sexual aversion at maturity. We discuss whether housing gibbons together before sexual maturity causes them to later reject each other as mates and therefore inhibits their reproductive potential. We conducted a survey of gibbons housed at zoos, conservation centers, and with private individuals. Our data suggest that early rearing experiences with potential mates do not prevent mating between gibbons housed together while immature. Using studbook data, we compared infant mortality in inbred and outbred captive gibbons. We found no significant difference in mortality rates for the 2 samples, though adverse effects of inbreeding may become apparent at later ages and in future generations. Our results indicate that early cohabitation is a feasible housing strategy for breeding programs and for rehabilitation/rescue projects in habitat countries where the main concern is the reproductive viability of gibbons.     

Positive Reinforcement Training for a Trunk Wash in Nepal's Working Elephants: Demonstrating Alternatives to Traditional Elephant Training Techniques

Many trainers of animals in the zoo now rely on positive reinforcement training to teach animals to voluntarily participate in husbandry and veterinary procedures in an effort to improve behavioral reliability, captive management, and welfare. However, captive elephant handlers in Nepal still rely heavily on punishment- and aversion-based methods. The aim of this project was to determine the effectiveness of secondary positive reinforcement (SPR) in training free-contact elephants in Nepal to voluntarily participate in a trunk wash for the purpose of tuberculosis testing. Five female elephants, 4 juveniles and 1 adult, were enrolled in the project. Data were collected in the form of minutes of training, number of offers made for each training task, and success rate for each task in performance tests. Four out of 5 elephants, all juveniles, successfully learned the trunk wash in 35 sessions or fewer, with each session lasting a mean duration of 12 min. The elephants' performance improved from a mean success rate of 39.0% to 89.3% during the course of the training. This study proves that it is feasible to efficiently train juvenile, free-contact, traditionally trained elephants in Nepal to voluntarily and reliably participate in a trunk wash using only SPR techniques.     

圈养婆罗洲猩猩部分血液参数值测定

采集6家动物园18只健康婆罗洲猩猩(Pongo pygmaeus)的24份血液样本,进行血液常规及生化参数检测。依据性别(雄性14份,雌性10份)和年龄(幼龄个体7份,亚成体6份,成体11份)对研究对象进行分组,分别统计不同组别样本的血液参数值,并进行组间比较。研究结果表明,雌、雄两组之间血液参数没有显著差异(One Way ANOVA test,P> 0.05)。淋巴细胞(LYM)比率随着年龄的增长而降低(One Way ANOVA test,F=5.200,P <0.05)。雄性成年个体血液中的谷丙转氨酶(ALT)浓度显著高于雌性个体(One Way ANOVA test,F=4.911,P <0.05),其他参数未呈现性别间差异(One Way ANOVA test,P> 0.05)。总蛋白(TP)呈现年龄组间的差异(One Way ANOVA test,F=4.715,P <0.05)。所检测圈养婆罗洲猩猩血液中葡萄糖含量较高,应在饲养过程中给予关注。     

Enhancing Nonhuman Primate Care and Welfare Through the Use of Positive Reinforcement Training

Nonhuman primates are excellent subjects for the enhancement of care and welfare through training. The broad range of species offers tremendous behavioral diversity, and individual primates show varying abilities to cope with the stressors of captivity, which differ depending on the venue. Biomedical facilities include small single cages, pair housing, and breeding corrals with large social groups. Zoos have social groupings of differing sizes, emphasizing public display and breeding. Sanctuaries have nonbreeding groups of varying sizes and often of mixed species. In every venue, the primary objective is to provide good quality care, with minimal stress. Positive reinforcement training improves care and reduces stress by enlisting a primate's voluntary cooperation with targeted activities, including both husbandry and medical procedures. It can also improve socialization, reduce abnormal behaviors, and increase species-typical behaviors. This article reviews the results already achieved with positive reinforcement training and suggests further possibilities for enhancing primate care and welfare.     

Positive Reinforcement Training for Blood Collection in Grizzly Bears (Ursus arctos horribilis) Results in Undetectable Elevations in Serum Cortisol Levels: A Preliminary Investigation

Training nonhuman animals in captivity for participation in routine husbandry procedures is believed to produce a lower stress environment compared with undergoing a general anesthetic event for the same procedure. This hypothesis rests largely on anecdotal evidence that the captive subjects appear more relaxed with the trained event. Blood markers of physiological stress responses were evaluated in 4 captive grizzly bears (Ursus arctos horribilis) who were clicker-trained for blood collection versus 4 bears who were chemically immobilized for blood collection. Serum cortisol and immunoglobulin A (IgA) and plasma β-endorphin were measured as indicators of responses to stress. Plasma β-endorphin was not different between the groups. Serum IgA was undetectable in all bears. Serum cortisol was undetectable in all trained bears, whereas chemically immobilized bears had marked cortisol elevations (p < .05). The highest cortisol elevations were found in 2 bears with extensive recent immobilization experience. These findings support the use of positive reinforcement training for routine health procedures to minimize anxiety.     

The Use of Positive Reinforcement in Training Zebra Sharks (Stegostoma fasciatum)

Few studies have examined how personality traits may be related to the amounts and types of attachments humans have toward companion animals (pets). In this study, 1,098 companion animal guardians (owners) completed a survey that included the Big Five Inventory, the Lexington Attachment to Pets Scale, and the Pet Attachment Questionnaire. Each participant chose whether he or she identified as a Cat Person, Dog Person, Both, or Neither. Results indicated that neuroticism, conscientiousness, choosing a dog as a favorite pet, and identifying as a Cat Person, Dog Person, or Both predicted affection for a pet. Conscientiousness, extraversion, and openness decreased avoidant attachment to pets, and neuroticism increased anxious attachment to pets. Both dogs and cats could benefit from pet owners who are conscientious, and there may be some benefits of neuroticism in pet owners. The findings of this study will advance understanding of the human–animal bond. As this understanding increases, measurements of human attachment and personality may be useful for the development of tools that could assist shelter employees and veterinarians in counseling people about pet ownership.     

Unexpected Ecological Resilience in Bornean Orangutans and Implications for Pulp and Paper Plantation Management

Ecological studies of orangutans have almost exclusively focused on populations living in primary or selectively logged rainforest. The response of orangutans to severe habitat degradation remains therefore poorly understood. Most experts assume that viable populations cannot survive outside undisturbed or slightly disturbed forests. This is a concern because nearly 75% of all orangutans live outside protected areas, where degradation of natural forests is likely to occur, or where these are replaced by planted forests. To improve our understanding of orangutan survival in highly altered forest habitats, we conducted population density surveys in two pulp and paper plantation concessions in East Kalimantan, Indonesia. These plantations consist of areas planted with fast-growing exotics intermixed with stands of highly degraded forests and scrublands. Our rapid surveys indicate unexpectedly high orangutan densities in plantation landscapes dominated by Acacia spp., although it remains unclear whether such landscapes can maintain long-term viable populations. These findings indicate the need to better understand how plantation-dominated landscapes can potentially be incorporated into orangutan conservation planning. Although we emphasize that plantations have less value for overall biodiversity conservation than natural forests, they could potentially boost the chances of orangutan survival. Our findings are based on a relatively short study and various methodological issues need to be addressed, but they suggest that orangutans may be more ecologically flexible than previously thought.     

Captive Reptile Mortality Rates in the Home and Implications for the Wildlife Trade

The trade in wildlife and keeping of exotic pets is subject to varying levels of national and international regulation and is a topic often attracting controversy. Reptiles are popular exotic pets and comprise a substantial component of the live animal trade. High mortality of traded animals raises welfare concerns, and also has implications for conservation if collection from the wild is required to meet demand. Mortality of reptiles can occur at any stage of the trade chain from collector to consumer. However, there is limited information on mortality rates of reptiles across trade chains, particularly amongst final consumers in the home. We investigated mortality rates of reptiles amongst consumers using a specialised technique for asking sensitive questions, additive Randomised Response Technique (aRRT), as well as direct questioning (DQ). Overall, 3.6% of snakes, chelonians and lizards died within one year of acquisition. Boas and pythons had the lowest reported mortality rates of 1.9% and chameleons had the highest at 28.2%. More than 97% of snakes, 87% of lizards and 69% of chelonians acquired by respondents over five years were reported to be captive bred and results suggest that mortality rates may be lowest for captive bred individuals. Estimates of mortality from aRRT and DQ did not differ significantly which is in line with our findings that respondents did not find questions about reptile mortality to be sensitive. This research suggests that captive reptile mortality in the home is rather low, and identifies those taxa where further effort could be made to reduce mortality rates.     

Nutrition of Captive Cheetahs: Food Composition and Blood Parameters

Diet and nutrition of cheetahs was evaluated through survey, in conjunction with chemical analysis of feed and plasma samples, as part of a multidisciplinary effort to investigate underlying causes of low reproductive success in North American captive cheetah populations. Cheetahs consumed an average of 1.32 ± 0.4 kg of food daily, containing approximately 1,800 kcal, and maintained an average body mass of 36.7 ± 1.0 kg (n = 34). A commercially prepared horsemeat-based mixture comprised the dietary staple in 10 of 13 zoos responding to the survey, with additional whole or carcass portions offered 1--2 days per week to maintain variety and provide periodontal stimulation. Seven of 13 respondents fasted animals 1 day/week; five maintained no fast days. The primary meat product (n = 14 samples) contained: 58% crude protein, 28% crude fat, 7% total ash, 52 Iu/kg vitamin E, 9.7 Iu/g vitamin A, and 2,200 mg/kg taurine (dry basis). Mineral content of the same food item was: 1.9% Ca, 10.0 mg/kg Cu, 645.2 mg/kg Fe, 0.08% Mg, 22.6 mg/kg Mn, 1.3% P, 0.4% Na, and 127.8 mg/kg Zn. Nutrient levels, except vitamin E (and possibly Mg), met or exceeded recommendations established for domestic felids. Plasma α-tocopherol, retinol, and taurine (18.1, 1.82, 128.4 μmol/L, respectively) concentrations were similar to normals for domestic felids, as were mean plasma mineral levels (n = 81; in mEq/L: 5.64 (Ca), 0.03 (Cu), 0.03 (Fe), 2.0 (Mg), 166.0 (Na), 12.3 (P), and 0.026 (Zn)). No gross physiological or dietary nutrient imbalances were evident from this survey. © 1993 Wiley-Liss, Inc.     

Positive Reinforcement Training Moderates Only High Levels of Abnormal Behavior in Singly Housed Rhesus Macaques

This study evaluated the application of positive reinforcement training (PRT) as an intervention for abnormal behaviors in singly housed laboratory rhesus macaques at 2 large primate facilities. Training involved basic control behaviors and body-part presentation. The study compared baseline behavioral data on 30 adult males and 33 adult females compared with 3 treatment phases presented in counterbalanced order: 6 min per week of PRT, 20 or 40 min per week of PRT, and 6 min per week of unstructured human interaction (HI). Within-subject parametric tests detected no main or interaction effects involving experimental phase. However, among a subset of subjects with levels of abnormal in the top quartile of the range (n = 15), abnormal behavior was reduced from 35% to 25% of samples with PRT but not with HI. These results suggest that short durations of PRT applied as enrichment for this species and in this context may not in itself be sufficient intervention for abnormal behavior because levels remained high. However, it may be appropriate as an adjunct to other interventions and may be best targeted to the most severely affected individuals.     

Cassava Trait Preferences of Men and Women Farmers in Nigeria: Implications for Breeding

Nigeria is the world’s largest cassava producer, hosting a diverse array of cassava farmers and processors. Cassava breeding programs prioritize “common denominator” traits in setting breeding agendas, to impact the largest possible number of people through improved varieties. This approach has been successful, but cassava adoption rates are less than expected, with room for improvement by integrating traits in demand by farmers and processors. This paper aims to inform breeding priority setting, by examining trait and varietal preferences of men and women cassava farmer/processors. Men and women in eight communities in Southwest and Southeast Nigeria were consulted using mixed methods. Women and men had significantly different patterns of cassava use in the Southwest. Fifty-five variety names were recorded from the communities demonstrating high genetic diversity maintained by growers, especially in the Southeast. High yield, early maturity, and root size were most important traits across both regions, while traits women and men preferred followed gender roles: women prioritized product quality/cooking traits, while men placed higher priority on agronomic traits. Trait preference patterns differed significantly between the Southeast and Southwest, and showed differentiation based on gender. Patterns of access to stem sources were determined more by region and religion than gender.     

Stability Over Time in the Preferences of Older Persons for Life-Sustaining Treatment

Objective: To measure the stability of life-sustaining treatment preferences amongst older people and analyse the factors that influence stability. Design: Longitudinal cohort study. Setting: Primary care centres, Granada (Spain). Eighty-five persons age 65 years or older. Participants filled out a questionnaire with six contexts of illness (LSPQ-e). They had to decide whether or not to receive treatment. Participants completed the questionnaire at baseline and 18 months later. Results: 86 percent of the patients did not change preferences. Sex, age, marital status, hospitalisation, and self-perception of health and pain did not affect preferences. Morbidity and the death of a relative did. Conclusion: Stability of preferences of older persons in relation to end-of-life decisions seems to be more probable than instability. Some factors, such as the death of a relative or the increase in morbidity, can change preferences. These findings have implications for advance directives (ADs) and advance care planning.     

A Comparison of Positive Reinforcement Training Techniques in Owl and Squirrel Monkeys: Time Required to Train to Reliability

This study compared the physiological response to novel situations in sex-separated and sex-mixed groups of horses, as measured by heart rate (HR). The study evaluated the possibility of training horses in a mixed-sex system. The study included 41 Purebred Arabian 2½-year-olds during their first walk on an automated horse walker. Four groups, divided by manner of care and training, consisted of 10 colts and 10 fillies kept in separate stables and trained in separate male or female groups and 12 colts and 9 fillies kept in the same stable and trained together. The study measured HR when horses were at rest before exercise, while moving from stable to walker, during 30 min of exercise on walker, while moving from walker to stable, and at rest after exercise. Mean HR scores recorded from training on the walker were higher in sex-mixed groups. Results obtained while horses were moving from stable to walker, then from walker to stable, were significantly higher in the sex-mixed groups. The study did not recommend training young horses in sex-mixed groups.