Chopped and dispersed food enhances foraging and reduces stress-related behaviours in captive white-naped mangabeys (Cercocebus lunulatus)

The white-naped mangabey is an endangered and rare zoo species, yet little is known concerning their welfare in captivity. The assessment of welfare should incorporate a net balance of negative and positive welfare behavioural indicators. These behaviours, and thus welfare, can be affected by the way food is presented based on its distribution, clumped or dispersed, and its size, chopped or whole. This study investigated the effect of food presentation on time-budget behaviours (i.e. forage, activity, inactivity, allogroom, self-groom, play) and stress-related measures (i.e., diarrhoea, aggression, self-directed behaviours), in four crossed-over test conditions of food distribution. The group-living mangabeys of Rotterdam Zoo were provided with vegetables that differed in distribution and size: clumped-chopped, dispersed-whole, dispersed-chopped, and clumped-whole. Mangabeys spent least time being inactive and subordinates and juveniles spent most time foraging during the dispersed-chopped condition, while the reversed was found during the clumped-whole condition. In addition, mangabeys stole food more often and engaged in less self-directed behaviours during dispersed-chopped, compared with dispersed-whole. In contrast, food distribution and size did not affect aggression, play, activity, self-grooming and diarrhoea. Consistent with most of the literature, chopped, dispersed items appeared to be the best, whereas presenting whole food items appeared to be the worst for welfare. In conclusion, presenting food in a distributed and chopped instead of whole manner is suggested to improve welfare of zoo-housed mangabeys

A Comparative Study of Chest CT With Lung Ultrasound After SARS-CoV-2 Infection in the Assessment of Pulmonary Lesions in Rhesus Monkeys (Macaca Mulatta)

Lung ultrasound (LUS) is a fast and non-invasive modality for the diagnosis of several diseases. In humans, LUS is nowadays of additional value for bedside screening of hospitalized SARS-CoV-2 infected patients. However, the diagnostic value of LUS in SARS-CoV-2 infected rhesus monkeys, with mild-to-moderate disease, is unknown. The aim of this observational study was to explore correlations of the LUS appearance of abnormalities with COVID-19-related lesions detected on computed tomography (CT). There were 28 adult female rhesus monkeys infected with SARS-CoV-2 included in this study. Chest CT and LUS were obtained pre-infection and 2-, 7-, and 14-days post infection. Twenty-five animals were sub-genomic PCR positive in their nose/throat swab for at least 1 day. CT images were scored based on the degree of involvement for lung lobe. LUS was scored based on the aeration and abnormalities for each part of the lungs, blinded to CT findings. Most common lesions observed on CT were ground glass opacities (GGOs) and crazy paving patterns. With LUS, confluent or multiple B-lines with or without pleural abnormalities were observed which is corresponding with GGOs on CT. The agreement between the two modalities was similar over the examination days. Pleural line abnormalities were clearly observed with LUS, but could be easily missed on CT. Nevertheless, due to the air interface LUS was not able to examine the complete volume of the lung. The sensitivity of LUS was high though the diagnostic efficacy for mild-to-moderate disease, as seen in macaques, was relatively low. This leaves CT the imaging modality of choice for diagnosis, monitoring, and longitudinal assessment of a SARS-CoV-2 infection in macaques