title: Fat soluble vitamins in blood and tissues of free-ranging and captive rhinoceros.
abstract: Several disease syndromes in captive rhinoceroses have been linked to low vitamin status. Blood samples from captive and free-ranging black (Diceros bicornis) and white rhinoceros (Ceratotherium simum) and tissue samples of captive individuals from four rhinoceros species were analysed for vitamins A and E. Circulating vitamin A levels measured as retinol for free-ranging versus captive black and white rhinoceros were 0.04 (+/- 0.03 SD) vs. 0.08 (+/- 0.08) and 0.07 (+/- 0.04) vs. 0.06 (+/- 0.02) microgram/ml, respectively. Circulating vitamin E levels measured as alpha-tocopherol were 0.58 (+/- 0.30) vs. 0.84 (+/- 0.96) and 0.62 (+/- 0.48) vs. 0.77 (+/- 0.32) microgram/ml, respectively. In contrast to earlier findings, there was no significant difference in vitamin E concentration between captive and free-ranging black rhinoceros. When the samples of captive black rhinoceros were grouped into those taken before 1990 and after 1990, however, those collected before 1990 had significantly lower (P < 0.001) vitamin E levels (0.46 +/- 0.83 microgram/ml) and those collected in 1990 or later significantly higher (P < 0.001) vitamin E levels (1.03 +/- 1.04 micrograms/ml) than the captive population as a whole. This is probably due to increased dietary supplementation. There were significant differences in circulating vitamin concentrations in black rhinoceroses from different regions in the wild. Serum 25-hydroxy (OH) vitamin D3 averaged 55.7 ng/ml in free-ranging rhinoceroses; no carotenoids were detected in any blood samples. Captive black and white rhinoceroses appear to be adequately supplemented in vitamin A and E. Captive Indian rhinoceroses (Rhinoceros unicornis) had significantly lower vitamin A concentrations in blood (P < 0.001) and higher vitamin A concentrations in liver tissue samples (P < 0.001) than other rhinoceros species. Equine requirements are not recommended as a model for rhinoceros vitamin requirements.
authors.affiliation: Institute of Animal Physiology, Physiological Chemistry and Animal Nutrition, Ludwig-Maximillians-University, Veterinaerstr. 13, 80539 Munich, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Clauss
authors.forename: David A
authors.initials: DA
authors.lastname: Jessup
authors.forename: Edward B
authors.initials: EB
authors.lastname: Norkus
authors.forename: Tai C
authors.initials: TC
authors.lastname: Chen
authors.forename: Michael F
authors.initials: MF
authors.lastname: Holick
authors.forename: W Juergen
authors.initials: WJ
authors.lastname: Streich
authors.forename: Ellen S
authors.initials: ES
authors.lastname: Dierenfeld
mesh_terms: D000273:Adipose Tissue / Q000737:chemistry; D000349:Africa; D000818:Animals; D000835:Animals, Wild / Q000097:blood / Q000378:metabolism*; D000836:Animals, Zoo / Q000097:blood / Q000378:metabolism*; D002112:Calcifediol / Q000097:blood; D002338:Carotenoids / Q000097:blood; D005260:Female; D008099:Liver / Q000737:chemistry; D008297:Male; D018482:Muscle, Skeletal / Q000737:chemistry; D009206:Myocardium / Q000737:chemistry; D009752:Nutritional Status; D010527:Perissodactyla / Q000097:blood / Q000378:metabolism*; D014801:Vitamin A / Q000032:analysis / Q000097:blood*; D014810:Vitamin E / Q000032:analysis / Q000097:blood*
chemical_list: D014801:Vitamin A; D014810:Vitamin E; D002338:Carotenoids; D002112:Calcifediol