Continuing Assessment of Vitamin Analysis Reliability Across Laboratories: Examples in White and Black Rhino Species


Sullivan K, Ardente A, Williams S, Livingston S, Valdes, E. 2017. Continuing Assessment of Vitamin Analysis Reliability Across Laboratories: Examples in White and Black Rhino Species. In Ward A, Coslik A, Brooks M Eds. Proceedings of the Twelfth Conference on Zoo and Wildlife Nutrition, Zoo and Wildlife Nutrition Foundation and AZA Nutrition Advisory Group, Frisco, TX.


As part of an ongoing assessment of vitamin E supplementation in white and black rhino species (2017 – 2018) at Disney’s Animal Kingdom, the first 6 months of assessment utilized 2 laboratories (A and B) for vitamin E analysis in split serum samples, and 2 laboratories (C and D) for vitamin E analysis in split fecal samples.  In both species (n = 3 each), fecal samples were taken every 2 weeks. Blood samples were taken every 2 weeks for black rhinos and every month for white rhinos.  Fecal samples had similar vitamin E concentrations when compared between labs C and D (n = 45; r = 0.67; p < 0.01). However, there were major differences seen in serum vitamin E levels between labs A (avg. ± SD; 1.3 ± 0.5 µg/mL) and B (0.7 ± 0.9 µg/mL), which had previously been utilized for a vitamin E study in elephants (Sullivan et al. 2016).  There was no discernable correlation between the split serum samples (n= 46; r = 0.14; p = 0.36). A possible cause of the vitamin E laboratory discrepancy was that Lab B was performing extra dilutions on serum samples, as their stated minimum sample volume was actually a minimum volume requiring dilution, not for analysis, hence raising the minimum detection limit. This was a key communication lesson, as some of our collection animals are able to readily provide a slightly larger quantity of blood through routine collection procedures. Due to continuing questions, minimal clinical samples have been sent to Lab B for the immediate future. Lab A, while reliable, may not be open to high frequencies of clinical samples, so may not be a viable option to use long term. We continue to work to find a commercial laboratory that can be relied on for consistent serum vitamin analysis, as well as having the ability to do mineral analyses. This is critical for correct nutritional assessment and supplementation plans for sensitive exotic species such as rhinos.

Sullivan Abstract NAG 2017 – Lab Comparisons7.18.pdf     58 KB