Evaluation of 25-hydroxy-vitamin D and parathyroid hormone in Callithrix penicillata primates living in their natural habitat in Brazil.

BACKGROUND: Vitamin D is a secosteroid hormone with important roles in the control of bone and mineral metabolism of vertebrates and in the maintenance of systemic homeostasis. This study aimed (i) to evaluate the serum concentrations of 25-hydroxy-vitamin D levels [25(OH)D], parathyroid hormone (PTH) and ionized calcium (iCa) of wild Callithrix penicillata (black-tufted marmosets) and (ii) to propose reference ranges for those analytes for free-living marmosets. METHODS: Blood samples were collected from 15 wild animals and analyzed for 25(OH)D, PTH and iCa. Reference values were calculated following standard analytical criteria. RESULTS: The observed mean serum levels (±standard deviation) were 25(OH)D, 61.7 (±20.8) ng/ml; PTH, 275.2 (±34.1) pg/ml; iCai 4.0 (±0.6) mg/dl. CONCLUSIONS: For free-living marmosets, the proposed physiological range for 25(OH)D is 20.1-103.3 ng/ml and for PTH is 207.0-343.3 pg/dl, with a confidence interval of 95%.

25-hydroxy-vitamin D levels among Callithrix penicillata primate species raised in captivity.

BACKGROUND: Animals in captivity should receive adequate sunlight exposure for sufficient generation of vitamin D [25(OH)D]. In the present study, 25(OH)D serum levels of 84 Callithrix penicillata primates were evaluated. OBJECTIVES: To determine 25(OH)D levels of those animals; to evaluate the influence of gender and period of sunlight exposure on their 25(OH)D levels. METHODS: Three groups were evaluated: group 1 (n = 29) on free sunlight exposure; group 2 (n = 34) on partial sunlight exposure; group 3 (n = 21) without sunlight exposure. RESULTS: The obtained 25(OH)D values were: group 1, 121.2 +/- 33.3 ng/ml; group 2, 115.2 +/- 32.2 ng/ml; group 3, 53.3 +/- 10.4 ng/ml. Significant statistical differences were obtained between groups 1 and 3 (p < 0.001) and groups 2 and 3 (p < 0.001); no statistical difference was found between genders. CONCLUSION: Direct sunlight exposure is essential for 25(OH)D sufficiency and it is proposed that the 25(OH)D normal range for captive Callithrix penicillata would be from 104.8 to 137.1 ng/ml (CI = 95%).