Fly food for tubes for behavioural assays (closed)

Published on Author Anne Petzold

Test 1 for different foods

Standard food dried out in the course of experiment (1 week in incubator at 25 DEG, tubes prepared with food 1 1/2 week before use).

Thus, tested 4 food preparations supposedly more moist than before:

  • 1 M Glucose in 1 % Agar
  • 3 M Glucose in 1 % Agar (Reference: Burke and Waddell 2011)
  • Standard Food:Agar 50:50
  • freshly prepared food

in up to 20 tubes (some flies drowned in the beginning) with 1 fly/tube in incubator at 20 DEG, then 25 DEG. Started 10.02.2014.

Results after 1 week (17.02.2014) @ 20 DEG

  • 1 M Glucose in 1 % Agar – looks juicy, 15/15 flies alive
  • 3 M Glucose in 1 % Agar – looks very dried up*, 9/19 flies alive
  • Standard Food:Agar 50:50 – looks ok, 19/19 flies alive
  • freshly prepared food – starts to dry up, 16/20 flies alive

* sugar crystallized, flies could probably not reach the non-crystallized part/water

Results after almost 2 weeks (21.02.2014) w/ 5 d @ 25 DEG

  • 1 M Glucose in 1 % Agar – looks juicy, 14/15 flies alive (1 looked drowned)
  • 3 M Glucose in 1 % Agar – looks very dried up*, 2/19 flies alive
  • Standard Food:Agar 50:50 – looks bit dried, 19/19 flies alive
  • freshly prepared food – looks dry, 14/20 flies alive

Results after 2 weeks (24.02.2014) after 1 week @ 20 DEG and 1 week @ 25 DEG

  • 1 M Glucose in 1 % Agar – still looks moist, 13/15 flies alive
  • 3 M Glucose in 1 % Agar – looks totally dried up, 0/19 flies alive
  • Standard Food:Agar 50:50 – starts to dry up, 17/19 flies alive
  • Freshly prepared food – looks totally dried up, 1/20 flies alive

* sugar crystallized, flies could probably not reach the non-crystallized part/water

Resolution: best use the Standard Food:Agar 50:50, because it keeps enough moisture to maintain the flies alive and, on the other hand, it certainly doesn’t interfere in the behavioural assay, as may do so the 1 M Glucose in 1 % Agar.

Test 2 for quality of Agar:Food mixture

Put Agar:Food mixture into tubes and put into incubator at 25 DEG for 2 weeks. Food looked very good, flies mostly survived.