How can i asses the parasie loading of littorina littoria?

[marineman]

I’m thinking of studying whether there is a parasite induced behavior in littorina littoria for my honors project but I’m not sure how to assess the parasite loading of them. Does anyone have any ideas about this? And if possible, if there is a way to assess the parasite load without damaging (too much) the littorina.as i want a before treatment and post treatment analysis. Any help would be appreciated. Thanks !

[JackBean]

If you didn't mind the damage, I'd suggest PCR. What kind of parasites are we talking about? Where are they located? How they behave?

[marineman]

I was hoping to assess the effect of secondary metabolites of several species of Rhodophycae to see if it produces an anti-parasitic response so i kinda need them to be as undamaged as possible. The trematodes would be located in the foot and digestive glands. Infection by the parasites would be in the forms o: rediae, sporocysts and metacercaria (basically cysts).

[wbla3335]

Your species has an operculum and is marine, so I'm not sure if this would work. We used to collect freshwater snails to see if they had schistosomes. The snails would release cercariae when transferred to a vial of water. We could then see the released cercariae when the vial was held up to a light. We never tried to quantify them, but it was a good fast and easy way to find the cercariae we were looking for. The water did not have to contain anything special - just the change of water was enough. We would bring snails back from a lake in a bucket of lake water and then just drop the snails into vials containing tap water.

[marineman]

Your species has an operculum and is marine, so I'm not sure if this would work. We used to collect freshwater snails to see if they had schistosomes. The snails would release cercariae when transferred to a vial of water. We could then see the released cercariae when the vial was held up to a light. We never tried to quantify them, but it was a good fast and easy way to find the cercariae we were looking for. The water did not have to contain anything special - just the change of water was enough. We would bring snails back from a lake in a bucket of lake water and then just drop the snails into vials containing tap water.

Thanks ill look into this, do you know any literature which has used this method? Do you know why the change in the water caused the release, was it temperature induced? or just stress induced?

[wbla3335]

I'm afraid I have no references and don't know the specific cause of the release of cercariae. I did this stuff 40 years ago.

[JackBean]

If it's in snails, can't you simply use many of them and cut few of them at each time point?

[marineman]

There is too much variation in the parasite loading of gastropods.