Concentrations of Progesterone During Storage of Whole Blood from Llama (Lama glama): Effects of Anticoagulants, Storage Time and Temperature

Abstract

Reproductive studies usually utilizes measurement of progesterone in various fluids such as plasma, serum or milk. It has been shown that progesterone concentrations in bovine whole blood decrease proportionally to: i) the time elapsed between the collection of the sample and the separation of plasma or serum from the erythrocytes and ii) the temperature of storage during this period (Breuel et al, 1988, Pulido et al. 1991). The addition of anticoagulants cause a more rapid decline in progesterone concentrations (Wiseman et al. 1982). In equine, porcine and canine blood samples storage time and temperature has a negligible effect on progesterone concentrations (Wiseman et al. 1982; Oltner & Edqvist 1982). Cordero et al. (1991) working with llama and alpaca whole blood, treated with EDTA as anticoagulant, reported a slight progesterone metabolization in alpaca plasma, but not in llama plasma.