Evaluation of different types of enrichment - their usage and effect on home cage behavior in female mice

Numerous studies ascertained positive effects of enriched environments on the well-being of laboratory animals including behavioral, physiological and neurochemical parameters. Conversely, such conclusions imply impaired animal welfare and health in barren husbandry conditions. Moreover, inappropriate housing of laboratory animals may deteriorate the quality of scientific data. Recommendations for housing laboratory animals stipulate that cages should be enriched to mitigate adverse effects of barren housing. In this context, it is not only unclear what exactly is meant by enrichment, but also how the animals themselves interact with the various items on offer. Focal animal observation of female C57BL/6J mice either housed in conventional (CON) or enriched (ENR) conditions served to analyze the impact of enriching housing on welfare related behavior patterns including stereotypical, maintenance, active social, and inactive behaviors. CON conditions resembled current usual housing of laboratory mice, whereas ENR mice received varying enrichment items including foraging, housing and structural elements, and a running disc. Active and inactive use of these elements was quantitatively assessed. CON mice showed significantly more inactive and stereotypical behavior than ENR mice. ENR mice frequently engaged with all enrichment elements, whereby riddles to obtain food reward and the running disc preferably served for active interactions. Offering a second level resulted in high active and inactive interactions. Structural elements fixed at the cagetop were least attractive for the mice. Overall, the presented data underline the positive welfare benefits of enrichment and that mice clearly differentiate between distinct enrichment types, demonstrating that the perspective of the animals themselves should also be taken into account when specifying laboratory housing conditions. This is particularly important, as the ensuring of animal welfare is an essential prerequisite for reliable, reproducible, and scientifically meaningful results.

Aktivitas harian harimau sumatra (Panthera tigris sumatrae) dan harimau benggala (Panthera tigris tigris) di Bali Zoo, Gianyar

Bali Zoo merupakan lembaga konservasi eksitu bagi berbagai jenis satwa, termasuk harimau benggala dan harimau sumatra. Kedua jenis ini termasuk dalam daftar IUCN dengan status terancam punah untuk harimau benggala dan status kritis untuk harimau sumatra. Penelitian ini bertujuan untuk mengetahui aktivitas harian kedua jenis harimau tersebut di Bali Zoo. Pengambilan dan pengumpulan data aktivitas harian dilakukan dengan metode focal animal sampling, pencatatan menggunakan metode instantaneous recording dengan interval 30 detik selama 30 menit. Pengambilan data dilakukan pada pagi, siang, dan sore hari. Kedua jenis harimau mengalokasikan waktunya paling banyak untuk beristirahat. Harimau sumatra mengalokasikan waktunya untuk istirahat sebesar 64,69 ± 2,52%, moving 31,32 ± 2,46%, grooming 2,72 ± 0,40%, buang air 0,37 ± 0,08%, makan 0,33 ± 0,11%, minum 0,31 ± 0,07% dan aktivitas sosial 0,26 ± 0,08%. Untuk harimau benggala, harimau ini mengalokasikan waktunya untuk istirahat sebesar 68,23± 2,20%, moving 24,14 ± 1,99%, sosial 3,54 ± 0,34%, grooming 2,23 ± 0,29%, buang air 0,39 ± 0,08%, minum 0,39 ± 0,09%, dan makan 0,08 ± 0,18%. Aktivitas pacing tercatat sangat rendah pada kedua jenis harimau mengindikasikan kondisi harimau yang cukup nyaman berada pada kandangnya.

Influence of environmental enrichment on the rehabilitation of white-eyed parakeet (Psittacara leucophthalmus)

The use of sensory, physical, cognitive, and alimentary stimuli are varieties of environmental enrichment used to minimize stress caused by the monotonous captive environment. The objective of this study was to verify the impact of environmental enrichment in escape-related behavioral stereotypies. Thirty birds of the species Psittacara leucophthalmus were observed from March to September 2016, received at the Wild Animal Recovery and Screening Center of the São Paulo State University (UNESP), School of the Veterinary Medicine campus Araçatuba. The methodology used for the behavioral observations was the focal animal with observation through filming were made by 18 hours per bird for three consecutive days, while physical, cognitive, food, and sensory enrichment methods were applied, and the assessment was carried out before, during, and after the application of environmental enrichment. The data were analyzed by the Shapiro-Wilk test for normality and by the Friedman test, which showed no significant difference (p >0.05) before, during, and after environmental enrichment. Despite the statistical analyses, the perception of the bird’s welfare improving was visually clear.

Observer effects in a remote population of large-headed capuchins, Sapajus macrocephalus

Human observers often are present when researchers record animal behavior, which can create observer effects. These effects are rarely explicitly investigated, often due to the assumption that the study animal is habituated to or unaffected by a human’s presence. We investigated the effect of human pressure gradients on a remote population of large-headed capuchins, Sapajus macrocephalus, looking specifically at the effects of number of observers, distance to observers, and distance to the research base. We conducted this study over 4 months in the Pacaya-Samiria Nature Reserve, Peru, and collected 199 two-minute focal samples of capuchin behavior. We found that capuchin monkeys fed less when human observers were closer to the focal individual, when more observers were present, and when capuchins were closer to the research base. We found no other consistent differences in capuchin monkey behavior across the measured human pressure gradients, although capuchins directed a high proportion of their vigilance toward humans (29% in adults and 47% in infants). Our results support the hypothesis that human pressure gradients influence animal behavior. Given the proportion of human directed vigilance, we recommend that all studies that use human observers to record animal behavior consider human-directed vigilance, record the number of observers, as well as the observer-focal animal distance, to check for these effects.

Is There a “Right” Side of Communicating Friendship? Lateralization of Social Interactions in Zoo Barbary macaques (Macaca sylvanus)

Social laterality in non-human primates has started to attract attention in recent years. The positioning of individuals during social interactions could possibly suggest the nature of a relationship and the social ranking of the subjects involved. The subjects of the present study were 12 adult Barbary macaques (Macaca sylvanus) housed in a zoological garden. We carried out fourteen 210-min video-recorded sessions and we used a focal animal sampling method to collect the position of the subjects during different social interactions. Data on the position of each macaque during three types of social interactions were collected (approach, proximity and affiliative contacts). Moreover, we focused on the outcomes of dyadic agonistic encounters to build the hierarchy of the colony. For each social interaction, two conditions were considered: the side preference (being kept on the left or on the right) and the sagittal preference (being kept in front or on the rear). Bouts of preference of different positions were collected for different social interactions (approach, proximity and contacts). No group-level side preferences were found for any social interaction, suggesting that both hemispheres might be complemental and balance each other during intraspecific communication. For the sagittal preference, we found a group-level bias for proximity, with macaques being kept in front rather than on the rear by close conspecifics. This might be due to the need to detect emotions and intentions of conspecifics. Moreover, high-ranking individuals are kept more frontally than on the rear when in proximity with other macaques. More studies are needed to better investigate social laterality, possibly distinguishing more categories of social interaction, and detecting other variables that might influence the positioning preferences.

The creation of phenomena in interactive biorobotics

In so-called interactive biorobotics, robotic models of living systems interact with animals in controlled experimental settings. By observing how the focal animal reacts to the stimuli delivered by the robot, one tests hypotheses concerning the determinants of animal behaviour in social contexts. Building on previous methodological reconstructions of interactive biorobotics, this article reflects on the claim, made by several authors in the field, that this strategy may enable one to explain social phenomena in animals. The answer offered here will be negative: interactive biorobotics does not contribute to the explanation of social phenomena. However, it may greatly contribute to the study of animal behaviour by creating social phenomena in the sense discussed by Ian Hacking, i.e. by precisely defining new phenomena to be explained. It will be also suggested that interactive biorobotics can be combined with more classical robot-based approaches to the study of living systems, leading to a so-called simulation-interactive strategy for the mechanistic explanation of social behaviour in animals.

Positional behavior and canopy use of black snub-nosed monkeys Rhinopithecus strykeri in the Gaoligong Mountains, Yunnan, China

Studies on positional behavior and canopy use are essential for understanding how arboreal animals adapt their morphological characteristics and behaviors to the challenges of their environment. This study explores canopy and substrate use along with positional behavior in adult black snub-nosed monkeys Rhinopithecus strykeri, an endemic, critically endangered primate species in Gaoligong Mountains, southwest China. Using continuous focal animal sampling, we collected data over a 52-month period and found that R. strykeri is highly arboreal primarily using the high layers of the forest canopy (15–30 m), along with the terminal zone of tree crowns (52.9%), medium substrates (41.5%), and oblique substrates (56.8%). We also found sex differences in canopy and substrate use. Females use the terminal zones (56.7% versus 40.4%), small/medium (77.7% versus 60.1%), and oblique (59.9% versus 46.5%) substrates significantly more than males. On the other hand, males spend more time on large/very large (39.9% versus 22.3%) and horizontal (49.7% versus 35.2%) substrates. Whereas both sexes mainly sit (84.7%), and stand quadrupedally (9.1%), males stand quadrupedally (11.5% versus 8.3%), and bipedally (2.9% versus 0.8%) more often than females. Clamber, quadrupedalism, and leap/drop are the main locomotor modes for both sexes. Rhinopithecus strykeri populations never enter canopies of degenerated secondary forest and mainly use terminal branches in the middle and upper layers of canopies in intact mid-montane moist evergreen broadleaf forest and hemlock coniferous broadleaf mixed forests across their habitat.

Mistaken identity may explain why male sea snakes (Aipysurus laevis, Elapidae, Hydrophiinae) “attack” scuba divers

Scuba-divers on tropical coral-reefs often report unprovoked “attacks” by highly venomous Olive sea snakes (Aipysurus laevis). Snakes swim directly towards divers, sometimes wrapping coils around the diver’s limbs and biting. Based on a focal animal observation study of free-ranging Olive sea snakes in the southern Great Barrier Reef, we suggest that these “attacks” are misdirected courtship responses. Approaches to divers were most common during the breeding season (winter) and were by males rather than by female snakes. Males also made repeated approaches, spent more time with the diver, and exhibited behaviours (such as coiling around a limb) also seen during courtship. Agitated rapid approaches by males, easily interpreted as “attacks”, often occurred after a courting male lost contact with a female he was pursuing, after interactions between rival males, or when a diver tried to flee from a male. These patterns suggest that “attacks” by sea snakes on humans result from mistaken identity during sexual interactions. Rapid approaches by females occurred when they were being chased by males. Divers that flee from snakes may inadvertently mimic the responses of female snakes to courtship, encouraging males to give chase. To prevent escalation of encounters, divers should keep still and avoid retaliation.

WILAYAH JELAJAH DAN AKTIVITAS HARIAN ELANG JAWA (Nisaetus bartelsi STRESEMANN, 1924) DI BUKIT MAYANA KECAMATAN KADUGEDE, KABUPATEN KUNINGAN

Abstrak : Elang jawa (Nisaetus bartelsi) merupakan jenis raptor dengan penyebaran terbatas (endemik). Elang jawa dilindungi oleh Peraturan Menteri Lingkungan Hidup dan Kehutanan Republik Indonesia Nomor P.92 tahun 2018 dan termasuk kategori endangered menurut IUCN Redlist (2017). Tujuan penelitian ini untuk mengetahui wilayah jelajah elang jawa dan aktivitas hariannya. Penelitian dilaksanakan di Bukit Mayana Kecamatan Kadugede, Kabupaten Kuningan selama 4 bulan dari Desember 2017 sampai Maret 2018. Metode yang digunakan yaitu Cooperative Method dan Focal Animal Sampling. Analisis wilayah jelajah menggunakan Minimum Convex Polygon dan Kernel Density Estimation dan analisis deskriptif untuk aktivitas harian. Berdasarkan hasil penelitian dan analisis didapatkan wilayah jelajah elang jawa dengan MCP individu Maya dan Yana masing-masing seluas 79.8 ha dan 189.9 serta KDE seluas 118.6 ha dan 180.6 ha. Aktivitas harian elang jawa di bukit Mayana yang paling banyak terlihat adalah terbang dengan presentase 79% sedangkan ketika tengger hanya sebesar 21%. Intensitas terbang paling tinggi mulai dari jam 09:00-11:30.Kata Kunci: Aktivitas harian, Wilayah jelajah, kernel density estimation, , Nisaetus bartelsi

Wild geladas (Theropithecus gelada) in crops—more than in pasture areas—reduce aggression and affiliation

Human–primate interfaces are expanding and, despite recent studies on primates from peri-urban environments, little research exists on the impact of agriculture and/or pasture areas on primate social behavior and health. We assessed how crop/pasture areas potentially alter social behavior and health of wild geladas (Theropithecus gelada) frequenting the unprotected area of Kundi (Ethiopia). We predicted that compared to pasture areas, crop areas (i) would be more challenging for geladas (prediction 1) and (ii) would have a greater impact on both aggressive and affiliative behavior, by reducing grooming time and enhancing competition (prediction 2). During January–May 2019 and December 2019–February 2020, we collected data (via scan, focal animal sampling, and video analyses) on direct human disturbance, external signs of pathologies and social behavior of 140 individuals from 14 one-male units and two all-male units. Animals experienced the highest level of human disturbance in crop areas (in line with prediction 1). Individuals from the groups preferentially frequenting crop areas showed the highest prevalence of external signs of pathologies consistent with chemical and biological contamination (alopecia/abnormally swollen parts). We collected 48 fecal samples. Samples from frequent crop users contained the highest rates of parasitic elements/gram (egg/larva/oocyst/cyst) from Entamoeba histolytica/dispar, a parasite common in human settlements of the Amhara region. In crop areas, subjects spent less time grooming but engaged in lower rates of intense aggression (in partial agreement with prediction 2). We speculate that the reduction in social behavior may be a tactic adopted by geladas to minimize the likelihood of detection and maximize food intake while foraging in crops.