DT's Cell Count-first pass

bmw

New member
After playing phone tag for the last two days I hooked up with my biologist friend.
Short version--gave the it to someone else to do--not happy with his procedure==did it himself, but was not happy with what ever the other guy did(dilution wrong?) - says it comes out to be 500 million per ml, but that could be off as much as 20% given what was done. Has another guy doing a procedure tonight- but says he may just want another sample to start from scratch. Any rate--he says 200-300 million/ml will probably be conservative.
Also mentioned--that using the "gate counter"? that this stuff is really small==most in the 1 to 2 micron range.
Mentioned that may be great for some organisms, usless to others. He is an "alga guy" but whould question the "coral guys". Let you know on any updates.

BTW--I just know this guy and another thru mutual friends--just downing a few beers and eating shrimp now and then. Didn't know there backgounds that well--thought just some lab guys-whew-I was very wrong. Now I got a couple of marine PH.d's comming to talk to my classes!! Maybe a tour or two of some labs.
Pretty good, yes? :)
b.
 
Hey B,

Thanks for the preliminary info. Very interesting.

Sounds like you have some pretty smart drinking buddies there.:)

Thanks again.

Doug
 
Doug-
thanks for the "thanks".
And for all that put down public education-the resources used for these and future results from these labs are done for "public school education" :) You all are sharing the results.
(BTW-how many of you think you could pass my calculus class? :D )
b.
 
BMW- I could pass it,maybe, I love math, went to private school and had calculus in 9th grade. Blew away most of the senior class in regular high school because I had done all of the senior curriculum in 9th and 10th grade. Now I'm a dumb adult :) who can't figure out how to program the damn VCR to record satellite shows :)
 
That's great, thanks BMW -- it's also right on the claims of the manufacturer (mean cell density ~2-3x10^8/ml), so that's good news. I have ordered some more bottles to check the cell density in the new batch and see how it looks. The size sounds a little small -- my bottle was predominately in the 3 micron range (average cell size of Nanno is about 2-4 um, so that's what I would expect), but that could have been just a slip there. I'll add my data to this estimate as soon as I get the new stuff....

Rob
 
I'm no big fan of cal. In my last semester, thank goodness. Getting ready fo differential equations....thats gonna be a pain as well. Why couldn't I just aim for an art degree....argh!! :) Stuck doing homework on a Friday night...and probably the rest of the weekend for that matter. Only real break is getting to vent on reef forums. Sorry for the babble...sometimes you just gotta get it out of ya though... :)

-Perry

oh yea, thanks for the good info!
 
biogeek -

if avg cell size is 2-4um, is that irrespective of cell age? ie are younger cells smaller? could it account for what the other lab's assay showed?
 
Hi:
just curious. We have gate counters at work, and if you set the gate to include or exclude doublets, triplets, etc, your counts will vary considerably. If I recall last time I counted the old DTs formulation on my machine most of the particles fell outside the lymphocyte gate (under 5micron). However clumps were around the 4-5+microns, if you just included the "clumps" as a 1 valve then you might get a better estimate, then having them excluded totally (a 0 valve). A simpler way to count these cells is to use a hemocytometer. this is a glass slide etched w/ a small 16box grid. You dilute your sample add a drop to the slide and physically count the cells under a 20X microscope. This way your eyes and include or exclude particle based on morphology. Particle counters either use electric potential or physical size as a criterion.
If I come across a bottle of concetrated DTs I'll give it a whirl.
frank
 
Frank,

Thanks for the information. It's nice to have a full fledged scientist on the board to give us this technical info. Especially nice since data is derived from civilian industry firms with dated equipment. Thanks again! I'm looking forward to reading the lab results from the concentrated DT's.

How does the Cryopaste product made by SF Bay Brand rate?
 
Hey Frank, I have a bottle sitting at home in my fridge if you want to stop over and grab a sample b-4 work or something. E-mail me. Oh crap, my E-mail is at work. Well, E-mail me anyway I'll get it on Monday, and we can hook up later in the week, or something.

DJ
 
I was hoping that this thread might catch your eye, Frank. I don't have a gated counter available to me anymore, so I have been doing the counts by eye with a hemocytometer, as well. The first bottle that I got and looked at gave me counts of just over a million cells per ml (1.3 - 3.0 million / ml) --as opposed to something between 80,000 and 100,000 cells per ml in the the old DT's. The reason that I asked for some more counts was that I sent my counts to Dennis, who told me that he expected numbers closer to 200-300 million cells per ml than the 2-3 million I found in my bottles.

Last time, the counts that you and I did were very similar, and if we got the same counts again, I would have to tell Dennis that something was wrong with his expectations. Unfortunately, the counts are not matching, which means that either I made a mistake on my initial dilutions (although it would have had to be the same mistake all 3 times which seems unlikely), there was something wrong with that first bottle that I got, or the samples are variable in the cell concentration depending on the batch. Two other independent sources have now provided counts on the 200-300 million cells per ml range, and that suggests that I probably got a reject bottle, but I would appreciate it if you have time to add another count to that testing to check out how consistent the cell concentrations are. I have a replacement bottle on the way from DT's, and will do another count as soon as I get it...

FWIW, examining the new DT's concentrate under a scope surprised me at how good it looked. If anything the new concentrated product is cleaner and better than the old dilute culture! This new product looks like one of the best live phytoplankton cultures I have seen offered in the trade -- very pure (I could not find anything other than Nanno in the samples I examined), no dead cells, ciliates or bacterial clumping visible in the 3 samples I examined! The Nanno cells were all very active, healthy and well-colored, so I think people will be happier than ever with the new product. The more concentrated stock allows a decrease in the total feeding amounts, shipping costs, and (very important for the spouse factor) storage space required in your fridge ;)

Also, for those interested, I've started trying to do some new kinds of testing on the various phytoplankton foods and Marine Snow, etc., that should be ready for WMC 2001 in Monterey...

Rob
 
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