Comparison of 25‐hydroxyvitamin D concentration in chimpanzee dried blood spots and serum

BackgroundDried blood spots (DBS) are used in human medicine to measure total 25‐hydroxyvitamin D (25‐OHD) in the blood. However, this easy and affordable sampling technique has not been evaluated in primates to measure vitamin D concentrations.ObjectivesWe aimed to compare 25‐OHD measurements in chimpanzee serum at two different laboratories and determine the precision and accuracy of the DBS method by comparing DBS and serum results.MethodsBlood samples from 17 captive chimpanzees were collected, and 25‐OHD3 and 25‐OHD2 were measured in serum at two accredited laboratories using liquid chromatography‐tandem mass spectrometry. The same analytes were measured on DBS cards, and results were compared with that of serum. Data were assessed using the Spearman correlation, Deming regression, and Bland‐Altman analyses. ResultsThe correlation coefficient between the two measurements in serum was r s = .51 (P = .04), and the mean bias was −1.25 ± 14.83. When comparing 25‐OHD concentrations measured in DBS and serum at the same laboratory, the r s was 0.7 (P = .002), and the mean bias was 1.42 ± 14.58. Estimated intra‐assay and inter‐assay coefficients of variation for DBS results were 6% and 12.6%, respectively. ConclusionsAlthough substantial analytical variability was found in 25‐OHD measurements regardless of the sample type, the identification of both constant and proportional error and wider limits of agreement with the DBS technique makes the interpretation of DBS results challenging, especially for values close to clinical cut‐off points. The DBS and serum methods were not interchangeable, and further studies are needed to validate DBS samples for vitamin D measurements in chimpanzees

An Exploration of the Value of Elective Health Checks in UK Zoo-Housed Gibbons

Elective health checks form an important part of the preventative healthcare of many zoo-housed animals. These procedures are not without risk or financial expenditure, meaning careful cost–benefit analysis is required when determining the frequency and intensity with which they are implemented. This study evaluated the value of elective health checks (n = 74) carried out on 33 gibbons at a single UK zoological collection from 2011 to 2018. Data were categorised by health check type, animal age, clinical findings and outcome. Univariable binary logistic regression and multivariable modelling were used to identify factors associated with the likelihood of actionable (clinically significant) outcomes. In total, 51.35% of all elective health checks resulted in an actionable outcome. Elderly heath checks had 13.64 times greater odds of an actionable outcome and 34 times greater odds of a significant radiographic finding, when compared to routine (non-elderly) health checks. Our findings suggest that 75% wild longevity is a suitable threshold for identifying elderly captive gibbons and increasing health check frequency. Whilst further work is needed to ascertain whether these findings can be extrapolated to other collections and/or species, this study demonstrates how the analysis of clinical data can aid in the implementation of an effective and evidence-based preventative healthcare plan

Diffuse Idiopathic Skeletal Hyperostosis in captive gorillas (Gorilla Spp.): Appearance and diagnosis

Diffuse idiopathic skeletal hyperostosis (DISH) is a disorder of unknown cause, in which new bone forms in soft tissues attached to the skeleton. Originally described in humans, in whom it is quite common, it is usually asymptomatic. New bone may completely bridge across joints, especially in the spine. However, it can be difficult to distinguish from diseases such as spondyloarthritis and spondylosis. With safer and increased use of radiography in diagnosis, the unfamiliar skeletal changes of asymptomatic DISH may now be coincidentally revealed during investigation of other disorders and result in misdiagnosis and unnecessary treatment. There have been case reports of its occurrence in great apes, but this is the first study to illustrate its appearances in a series of 11 skeletons of western and eastern lowland gorillas (Gorilla gorilla gorilla and Gorilla beringei graueri) from zoos in Europe and the United States. The study combines a review of available clinical and postmortem records with examination of the skeletons and radiologic investigation, such as computed tomography (CT). The results indicate that the disorder is probably common in older (>30 yr) captive gorillas, but that it is asymptomatic. It was not symptomatic during life in any of these animals. Several cases had unexpected features, such as extensive involvement of the thorax and extra-articular sacroiliac and tibiofibular joint fusions that are not typical in humans. By illustrating these skeletons, the study should aid differentiation of DISH from spondylosis (syn spondylosis deformans) and spondyloarhritis. It illustrates those features that are atypical of human DISH. CT scanning is valuable in such cases for examining diagnostically important areas such as sacroiliac joints. Increased awareness of DISH should help with understanding its cause, both in gorillas and humans

DIFFUSE IDIOPATHIC SKELETAL HYPEROSTOSIS IN CAPTIVE GORILLAS (GORILLA SPP.): APPEARANCES AND DIAGNOSIS.

Diffuse idiopathic skeletal hyperostosis (DISH) is a disorder of unknown cause, in which new bone forms in soft tissues attached to the skeleton. Originally described in humans, in whom it is quite common, it is usually asymptomatic. New bone may completely bridge across joints, especially in the spine. However, it can be difficult to distinguish from diseases such as spondyloarthritis and spondylosis. With safer and increased use of radiography in diagnosis, the unfamiliar skeletal changes of asymptomatic DISH may now be coincidentally revealed during investigation of other disorders and result in misdiagnosis and unnecessary treatment. There have been case reports of its occurrence in great apes, but this is the first study to illustrate its appearances in a series of 11 skeletons of western and eastern lowland gorillas (Gorilla gorilla gorilla and Gorilla beringei graueri) from zoos in Europe and the United States. The study combines a review of available clinical and postmortem records with examination of the skeletons and radiologic investigation, such as computed tomography (CT). The results indicate that the disorder is probably common in older (>30 yr) captive gorillas, but that it is asymptomatic. It was not symptomatic during life in any of these animals. Several cases had unexpected features, such as extensive involvement of the thorax and extra-articular sacroiliac and tibiofibular joint fusions that are not typical in humans. By illustrating these skeletons, the study should aid differentiation of DISH from spondylosis (syn spondylosis deformans) and spondyloarhritis. It illustrates those features that are atypical of human DISH. CT scanning is valuable in such cases for examining diagnostically important areas such as sacroiliac joints. Increased awareness of DISH should help with understanding its cause, both in gorillas and humans.Non