Factors associated with low vitamin D status of Australian alpacas

• Published in: Australian veterinary journal Vol. 86; no. 12; pp. 486 - 490
• Main Authors: Judson, G.J, McGregor, B.A, Partington, D.L
• Format: Journal Article
• Language: English
• Published: Melbourne, Australia Blackwell Publishing Asia 01.12.2008
• Subjects: alpaca; alpacas; Animals; Australia - epidemiology; blood chemistry; blood plasma; breed differences; breeds; Camelids, New World - blood; color; Female; fleece; fleece color; fleece colour; Hair; Huacaya (alpaca breed); Male; Nutritional Status; phosphorus; Pigmentation - physiology; Poaceae; Risk Factors; season; seasonal variation; Seasons; summer; Suri (alpaca breed); vitamin D; Vitamin D - analogs & derivatives; Vitamin D - blood; Vitamin D Deficiency - blood; Vitamin D Deficiency - epidemiology; Vitamin D Deficiency - veterinary; vitamin deficiencies; winter; young animals; South Australia
• ISSN: 0005-0423; 1751-0813
• DOI: 10.1111/j.1751-0813.2008.00367.x

Objective  To investigate factors associated with low vitamin D status of alpacas at pasture in southern Australia. Design  A 2‐year survey of alpacas from two farms in South Australia and three in Victoria. Blood samples were collected from 20 to 30 alpacas on each farm on five occasions each year. Breed, gender, age and fleece colour of animals were recorded. Method  Blood samples were assayed for plasma 2.5‐hydroxycholecalciferol (25‐OH D3) and plasma inorganic phosphorus (Pi). Data sets from 802 animal samples were analysed by multiple regression to determine variables associated with low vitamin D status of alpacas. The relationship between plasma 25‐OH D3 and plasma Pi was also investigated. Results  Vitamin D status was significantly affected by month of sampling, with low values in late winter and high values in summer. Plasma vitamin D concentrations increased with age, were higher in alpacas with light fleeces than in those with dark fleeces and were also higher in the Suri than in the Huacaya breed. Plasma Pi concentrations were generally lower in alpacas with plasma 25‐OH D3 values < 25 nmol/L. Conclusions  Young alpacas with dark fleeces are most at risk from vitamin D insufficiency in late winter in southern Australia. The present study indicates that plasma Pi values are not a reliable indicator of vitamin D status of alpacas as assessed by plasma 25‐OH D3 concentrations.