Kemp, K. 2018. Ultrasound to UltraSee: The use of ultrasound to determine pregnancy in mice. Animal Technology and Welfare 17(3), 193-195 (IAT Congress 2018 Poster Presentation).

In March 2017 MRC Ares bought an ultrasound machine to assist in determining pregnancy in timed mating mice. Prior to this, visual checks or palpation would be used to confirm pregnancy. There were limitations with these methods as mice generally are not visibly pregnant until E12.5, palpation is not possible before E9.5 and is not always accurate. Embryos are required for use at earlier time points which meant females had to be used regardless as there was no way of confirming pregnancy. This led to animals being culled unnecessarily, experimental delays and time lost undertaking unnecessary dissections. The equipment and method are described. In March 2018, 44 scans were carried out at different time points ranging from E7.5–12.5. 66% scanned correctly as pregnant 25% scanned correctly as not pregnant – Success rate of 91%! The 25% not pregnant were reused. Based on the gestation points of these females, before the ultrasound scanner, 45% of these females would have been culled regardless of pregnancy as they would have been too early to palpate.