18.104.22.168.2. Spore suspension concentration
Dilution of the purified spore suspension to the desired concentration can be performed using the formula: C1V1 = C2V2 where: C1 = initial concentration; V1 = initial volume; C2 = final concentration; V2 = final volume.
example, if you want to feed 10,000 Nosema
spores in 10 µl 50 % (weight / volume) sucrose solution, you must, as
determined by proportions, create a final spore concentration of 1,000,000
spores / ml of 50 % (w/v) sucrose solution. To create 10 ml of this final spore
suspension in 50 % sucrose solution when your initial spore suspension is:
Example 1. 10,000,000 spores / ml water, then 1 ml of initial spore suspension must be added to 9 ml 55.6 % (w / v) sucrose solution. See below for specific details:
Calculating initial volume of spore-water suspension needed
- C1V1 = C2V2
- V1 = C2V2/C1
- V1 = 1,000,000 spores per ml X 10 ml / 10,000,000 spores per ml
- V1 = 1 ml
Calculating initial concentration of spore-free sucrose solution needed*
- C1V1 = C2V2
- C1 = C2V2 / V1
- C1 = 50 g sucrose per 100 ml water X 10 ml final sucrose solution / 9 initial sucrose solution
- 55.56 g sucrose per 100 ml water
*An initial concentration of spore-free sucrose solution of 50 % is generally adequate when a low volume of spore suspension is added to create a final spore suspension in approximately 50 % sucrose solution.
Example 2. 12,456,000 spores / ml water, then 0.8 ml of initial spore suspension must be added to 9.2 ml 54.3 % (w / v) sucrose solution.
Control suspensions to infected control bees should be created using uninfected individuals from the same colonies the spores were sourced from.