Rhinoceromics -Relation between microbiome, mycobiome and diet composition on TS% levels in captive black rhinoceros (Diceros bicornis michaeli). Rhinoceromics

In 5 European zoological institutions, samples were taken from black rhinoceroses every two months as part of routine health checks. From April 2021 to April 2022, these institutions were asked to store samples for this study on a bi-monthly basis and to collect additional samples: 2 x 2 ml heparin plasma, 2 x 500 µl EDTA whole blood, 2 ml serum and 300-500 g fresh found feces stored at -20°C. After every 1-2 rounds, the samples were professionally shipped frozen (BioLogistic Services) to the laboratory at the University of Applied Sciences in Leiden, the Netherlands. There, the samples were thawed, split, and refrozen. The frozen samples were then distributed to the other laboratories. To minimize environmental contamination, the outer part of the frozen fecal samples was removed with a saw and discarded. 100 g of frozen fecal sample was then mixed with 100 ml of MQ water in a metal blender cup until a smooth paste was obtained for DNA extraction. Extracted DNA was used to profile each fecal sample by 16S rRNA, ITS2, and matK biomarkers. The same fecal samples were used for SCFA analysis. Blood and serum samples were used for the measurements of insulin, saa, ifn- tnf-, Il6, vitamin D, and transferrin saturation. Additionally, a questionnaire was sent out to the institutions regarding health status (symptoms of disorder, etc) and information concerning the composition of the diet.