Wax Worm/P. larvae LD50

From 3-2-15.

Day 6
Checked the survival of the wax worms that were fed the bacterial spores. Once again, all the wax worms in the P. larvae spore treatment groups were accounted for alive and well. However, the wax worms in the B. thur. groups have begun to have visible signs of illness, as seen in the multiple images below. I would assume these blemishes on their bodies are due to ingestion of the B. thur spores. The wax worm bodies are covered in round dark wounds that almost look like burns.

"burns" on the outside of the wax worm

Dead wax worm (brown color)

Another wax worms with visible signs of disease

Below are several pictures of the wax worms from the P. larvae treatment groups for comparison. The wax worms were all fed spores at similar instars. The below wax worms do not possess the visible signs of disease.

Healthy wax worm from P. larvae treatment group

No visible signs of disease

Healthy wax worm

Since I still have left over BAD/spore dilution made up that have since been stored in the 4C fridge from 2-25-15 I set up the ingestion LD50 experiment again with a few modifications. Only the 1:5 and 1:25 dilutions were used from each of the spore stocks (P. larvae and B. thur) and no wax pellets were added to the containers. As before, 100 uL of the spore dilutions in BAD were added to the center of the small containers with 10 early instar wax worms to each treatment group. I want to see if there is a difference between adding the wax pellets and them not being present. I speculate that the presence of the wax pellets either dilute or nullify the effects of the spores to cause disease, or that only by having them there were the spore ingested at all (since the wax worms ate the wax that was coated in spores). Below is a picture of the set-up for this new experiment:

A cover was placed on each container and incubated in the 30C walk in incubator. I will continue to monitor the survival of each of these experiments.

/EWW