01-17-2013, 04:29 AM
A few days back, I was having a discussion with several other frog nerds about mites in fly cultures. Everyone seemed to have a differing opinion on how they get into the cultures.
One thought that the mites are pretty much ever present in the cultures due to the materials used.
Another thought that the mites migrated from the environment into the cultures, so preventative measures were the only way.
Yet another mentioned that they may get introduced at some point and then get carried between cultures by the flies - even prior to the 30 day mark that is their generally accepted life cycle time.
Being the guy I am, I tend not to just take peoples word for it. I like to see things with my own eyeballs and confirm, at least in my own (and albeit highly unscientific) way.
My cultures have always been very clean, I rarely see mites due to very strict culturing practices, keeping cultures on fresh mite paper, not keeping mites past 30 days, using boiling water in media, etc. I am mite-free I thought.. not so fast.
In my experiment, I took two cultures from approx. 10, 15, and 25 days after culture. I usually make batches from two separate brands of media(why I do this .. I have no explanation for that, but I digress), represented by Repashy Superfly, and NEHerp's Media.
I swabbed every culture, and also took about 6-8 flies from each and smashed their heads with fine tweezers(to keep them from running away, and to preserve anything that may be attached to them ).
I busted out my 2000x stereoscopic microscope, and went to town.
First off, I took some samples of the medias that I am using - All came back clean in every sample. No mites present that I could see at any magnification.
Culture cups/lids were clean, nothing present.
I flip flop back and forth between excelsior and coffee filters - neither of which did I find any mites on after about an hour panning the stage around.
At this point it seems unlikely that mites that would take interest in FF cultures would be present on these materials, unless they were migrating across them to get to the fly cultures.
On with the flies / swabs.
10 days after culture:
No visible mites present on any swabs, or any of the flies from either media
15 days after culture:
Few VERY tiny mites on swabs. Also found what appear to be baby mites clinging to flies
25 days after culture:
Nearly adult mites on swabs. Few larger baby mites clinging to flies. Nothing on cup visible to the naked eye.
This was interesting to me, as I had always assumed that my cultures were clean, when in fact they were just as mite riddled as any other. Not only that, but the mites were hitching a free ride over to fresh cultures, even if I make new cultures in about the middle of the current cultures life. I suppose I was just out culturing the mites - getting rid of the old cultures before the babies had a chance to become visible, and the adults were too few to be readily noticeable.
While I am sure that given a situation when cultures are set out unprotected, mites will migrate into a culture and make the infestation worse - this is unlikely to occur in cultures kept with some method of prevention (sprays, paper, powder).
From what I am seeing, even protected cultures that "look" mite free, with 100% clean culturing materials, may have them in some capacity and they are just transferring between cultures on the flies.
Any thoughts/experiences/comments on this?
P.S. if you really want to be creeped out, here is a video I took of the mite climbing around on the fly(ignore daughters jibber jabber in the audio - she was being my lab helper):
[youtube]1Tiwrp0w6x4[/youtube]
watch it in 720, and keep an eye to the right. You'll see it climb up on the body and then on the flies leg.
One thought that the mites are pretty much ever present in the cultures due to the materials used.
Another thought that the mites migrated from the environment into the cultures, so preventative measures were the only way.
Yet another mentioned that they may get introduced at some point and then get carried between cultures by the flies - even prior to the 30 day mark that is their generally accepted life cycle time.
Being the guy I am, I tend not to just take peoples word for it. I like to see things with my own eyeballs and confirm, at least in my own (and albeit highly unscientific) way.
My cultures have always been very clean, I rarely see mites due to very strict culturing practices, keeping cultures on fresh mite paper, not keeping mites past 30 days, using boiling water in media, etc. I am mite-free I thought.. not so fast.
In my experiment, I took two cultures from approx. 10, 15, and 25 days after culture. I usually make batches from two separate brands of media(why I do this .. I have no explanation for that, but I digress), represented by Repashy Superfly, and NEHerp's Media.
I swabbed every culture, and also took about 6-8 flies from each and smashed their heads with fine tweezers(to keep them from running away, and to preserve anything that may be attached to them ).
I busted out my 2000x stereoscopic microscope, and went to town.
First off, I took some samples of the medias that I am using - All came back clean in every sample. No mites present that I could see at any magnification.
Culture cups/lids were clean, nothing present.
I flip flop back and forth between excelsior and coffee filters - neither of which did I find any mites on after about an hour panning the stage around.
At this point it seems unlikely that mites that would take interest in FF cultures would be present on these materials, unless they were migrating across them to get to the fly cultures.
On with the flies / swabs.
10 days after culture:
No visible mites present on any swabs, or any of the flies from either media
15 days after culture:
Few VERY tiny mites on swabs. Also found what appear to be baby mites clinging to flies
25 days after culture:
Nearly adult mites on swabs. Few larger baby mites clinging to flies. Nothing on cup visible to the naked eye.
This was interesting to me, as I had always assumed that my cultures were clean, when in fact they were just as mite riddled as any other. Not only that, but the mites were hitching a free ride over to fresh cultures, even if I make new cultures in about the middle of the current cultures life. I suppose I was just out culturing the mites - getting rid of the old cultures before the babies had a chance to become visible, and the adults were too few to be readily noticeable.
While I am sure that given a situation when cultures are set out unprotected, mites will migrate into a culture and make the infestation worse - this is unlikely to occur in cultures kept with some method of prevention (sprays, paper, powder).
From what I am seeing, even protected cultures that "look" mite free, with 100% clean culturing materials, may have them in some capacity and they are just transferring between cultures on the flies.
Any thoughts/experiences/comments on this?
P.S. if you really want to be creeped out, here is a video I took of the mite climbing around on the fly(ignore daughters jibber jabber in the audio - she was being my lab helper):
[youtube]1Tiwrp0w6x4[/youtube]
watch it in 720, and keep an eye to the right. You'll see it climb up on the body and then on the flies leg.