Effects of different storage conditions and storage times on progesterone concentration in reindeer blood on filter paper

Abstract

Numbers of Rangifer are declining rapidly; therefore appropriate measures to slow down or stop the decline in numbers have to be implemented. In order to do that, detailed knowledge about the animals is needed. One important piece of information about herd status is the pregnancy rate. Measurement of blood progesterone concentration has been proven effective for pregnancy diagnosis in ruminants and, consequently plasma progesterone levels have been commonly used for pregnancy diagnosis in Rangifer as well. But there is still a major problem: It is very difficult to collect blood samples from wildlife in the Arctic. Conventional sampling methods are not very well suited for the harsh environmental conditions. One good alternative to conventional blood collection methods is the use of filter paper (FP). But as FPs have never been used for measuring progesterone in Rangifer, the first objective of the present study is to determine whether FP blood samples are suitable for this purpose. The second is to assess how different collection/storage conditions and times affect the detection of progesterone using this tool. Results show that FPs can be used for measuring progesterone, but that the measured values are different from the measured serum values. There is no difference between the different collection and storage conditions but there is a significant difference between the 1 week and 1 month storage times. Before the use of FPs for measuring progesterone can be implemented, more extensive research is needed.