Behavioral analysis of a captive male Bornean orangutan (Pongo pygmaeus) when exposed to environmental changes

Understanding the species-specific behavioral needs of Bornean orangutans (Pongo pygmaeus) has led zoological gardens to focus on creating more natural and stimulating facilities. Studies have documented enhanced welfare through various methods, including environmental enrichment like mixed-species habitats, which could improve animal welfare. This study aimed to evaluate the behavioral adaption following the transfer to a new facility and the possible effects of environmental enrichment on an orangutan in captivity at Aalborg Zoo in Denmark. A newly arrived male was observed for analyzing behavioral changes in the weeks after relocation and introducing two small-clawed Asian otters (Aonyx cinereus) to the facility. Changes in behavior were analyzed using recorded behavior and an ethogram before and after the introduction of the otters. The expression of behaviors associated with stress and individual plasticity was analyzed, and the results indicated a change in the behavioral phenotype in response to the introduction of the otters. The study shows that behaviors associated with stress decreased after the introduction of small-clawed otters, suggesting that it had a positive effect on the behavior of the orangutan.</p

Longitudinal monoaminergic PET imaging of chronic proteasome inhibition in minipigs

Impairment of the ubiquitin proteasome system has been implicated in Parkinson’s disease. We used positron emission tomography to investigate longitudinal effects of chronic intracerebroventricular exposure to the proteasome inhibitor lactacystin on monoaminergic projections and neuroinflammation. Göttingen minipigs were implanted in the cisterna magna with a catheter connected to a subcutaneous injection port. Minipigs were imaged at baseline and after cumulative doses of 200 and 400 μg lactacystin, respectively. Main radioligands included [11C]-DTBZ (vesicular monoamine transporter type 2) and [11C]-yohimbine (α2-adrenoceptor). [11C]-DASB (serotonin transporter) and [11C]-PK11195 (activated microglia) became available later in the study and we present their results in a smaller subset of animals for information purposes only. Striatal [11C]-DTBZ binding potentials decreased significantly by 16% after 200 μg compared to baseline, but the decrease was not sustained after 400 μg (n = 6). [11C]-yohimbine volume of distribution increased by 18–25% in the pons, grey matter and the thalamus after 200 μg, which persisted at 400 μg (n = 6). In the later subset of minipigs, we observed decreased [11C]-DASB (n = 5) and increased [11C]-PK11195 (n = 3) uptake after 200 μg. These changes may mimic monoaminergic changes and compensatory responses in early Parkinson’s disease