Vitamin D Content in Milk of the Rhesus Monkey.

Objective: Milk is the first and continued source of ingested Vitamin D. Extensive studies have been carried out in humans measuring Vitamin D in lactating mothers but to date few values have been obtained for milk of non-human primates and none for rhesus monkeys. Consequently. we have determined Vitamin D and antirachitic activity (ARA) in milk samples obtained from 21 rhesus monkeys. Methods: Lactating dams were sampled by hand-stripping. 25(OH)D2, Vitamin D2, 25(OH)D3, Vitamin D3 and ARA were assessed in foremilk using LC-MS/MS techniques. Results: 25(OH)D2 and Vitamin D2 were below detectible limits (<0.5 ng/g), 25(OH) D3 =4.2 ± 1.8 ng/ml, Vitamin D3 = 6.1 ± 3.1 ng/ml and ARA = 1080 ± 480 IU/L. Conclusions: This is the first report of content of Vitamin D and ARA activity in foremilk of the rhesus monkey and can serve as a reference for future studies.