DK's m..a..d.. d..o..-i..n..g..s........

[mordalphus]

so in other words, when crs are stressed, they constrict their chromatophores to become pale, and calcium ions are responsible for this action?

[DKShrimporium]

Originally Posted by mordalphus

so in other words, when crs are stressed, they constrict their chromatophores to become pale, and calcium ions are responsible for this action?

Well, the study concludes that calcium ions are needed for the transport, but they don't know which direction it's used in: the expansion, or contraction, of the area of pigment. But the process whereby the pigment moves needs calcium ions present. In many cases in physiology, however, the calcium ion is used to mediate the active process (i.e., as long as calcium is present, the engine is running, and then is pumped back across a membrane afterward as the process goes quiescent and passive).

Based on my personal observations, I'd guess that the calcium is used in the dispersion of pigment - that the act of EXPANDING the pigment area is the active process, and the act of retracting the pigment area is the passive process. It could be that there are different mediators involved in the different directions, too. Usually, in physiological systems, there is a sort of baseline level of activity that is moderated up or down - it's not just as simple as an on-off switch.

My guess is that calcium ions are used toward the active process, and that the active process is that of expanding pigment, and that inhibition results in passive retraction of the pigment.

Why I think this is that if you keep crystals relatively happy, they are fairly pigmented (so, a moderate level of active process going on, all the time, as baseline). But if you make them really happy, their pigment intensifies, such as when you finally feed them after a few days of not feeding. Cuttlefish increase their pigment into big displays in response to stress, positive or negative stress. This suggests that increasing the pigment area is the active process.

It's likely a lot more complicated that this, too. Usually, in physiological systems there is a reservoir of the thing like calcium that is under pump action that in the resting state the pumps are pumping the calcium into the reservoir and keeping a level of calcium in the reservoir. Then, when a stimulus comes for activity, the reservoir membranes are altered such that they leak the calcium out of the reservoir, and into a general area, where something else has calcium receptors that, when filled with calcium, make something else happen. So, the calcium, when loose, randomly finds a receptor to park in, causes a reaction, then eventually gets removed from the receptor via a recycling enzyme, and then pumped back into the reservoir, whose membranes have now recovered and are no longer leaky.

Biology is coo-el.

[mordalphus]

the act of retracting the pigment area is the passive process

That sounds about right, because often if you look at CRS at night, their coloration is faded while in a resting mode. Not all of them, but I can pick out a few that are brilliantly white during the day, and faded about 6 hours after lights off.

Interesting for sure!

[ZID ZULANDER]

I find it hard to drip acclimate for a long time only because of the amount of water normally supplied but the shipper is low. I have wanted to automate here but with glass tanks that means drilling holes in glass. Not so much fun. I am in the process of switching my tanks to acrylic since its easier to drill and insulates better. The tanks are in the garage and this winter even though I am in CA was cold and the electric bill was high.


"I'm makin' me some very high end acclimation chambers - set it and forget it style, because DK is sorta lazy and doesn't like to babysit things but rather likes to automate things - where I can drip high-end incoming livestock for days, or even weeks, for a VEEEEEEEEEEEEEEEEERY slow change in water conditions, until I get them where I want them."

[mordalphus]

I drip acclimate in a 2 gallon bucket, placed in a 5 gallon bucket and generally do it overnight or however long it takes me to remember that i'm drip acclimating, lol.

Sounds cool though

[ZID ZULANDER]

so how does that work when you are being sent like a cup of water or just a little more. In a 2 gallon bucket wouldnt the shrimp be out of water?

Originally Posted by mordalphus

I drip acclimate in a 2 gallon bucket, placed in a 5 gallon bucket and generally do it overnight or however long it takes me to remember that i'm drip acclimating, lol.

Sounds cool though

[mordalphus]

Nah, they have about a centimeter of water usually. If the seller put less water than normal I'll use a dip'n'pour instead of the 2 gallon bucket, and still place it in the bottom of an empty 5 gallon bucket.

I usually buy over a hundred shrimp at a time though, so I generally have about a quart of water or a little more.

[DKShrimporium]

I believe in method. In constancy and reproducibility (after I get done fiddling with variables, that is - LOL!!).

So today, I finally broke down and bought me this bad boy. It's a 1000-5000 microliter pipetman that will accurately dispense between 1 and 5 ml (it's adjustable, that is), every time. It's accurate and reproducible to 0.5%. No more messing with those stupid test tubes and the little mark, and getting a few drops more or less into them. But I have more important uses for this thing, too... (I bought the graduated cylinders to go with it a few months ago...)

(Don... Josh... are you reading??)

I once spent an entire week being trained by Lloyd's of London in Lloyd's Register Quality Assurance - no joke (that instructor was the most anal, obsessive-compulsive professional I had ever encountered), and it sort of polluted my mind... toward QA/QC
Carry on...

[DKShrimporium]

Bad Boy arrived today, freshly calibrated to third decimal place accuracy.

I set up a jig and used my new plastics bit to drill the micro-tanks. Here's a shot of the installed mini-bulkheads. These tanks are useful for acclimation, quarantine, medication, selective breeding.

[dbosman@msu.edu]

Let me know what size pipet tips it takes.
The university surplus occasionally has boxes that are no longer useful for what ever lab they came out of. One never knows what one will find.
Today I got four pieces of perfect for LED light fixture - aluminum extrusions. They were originally a HEPA filter frame.

[DKShrimporium]

Bad Boy takes 1000-5000 microliter tips, but I will undoubtedly be investing in a 100-1000 microliter pipettor soon, too, so those two sizes I will use. I plan to reuse them as much as possible, though. I was horrified to see how much tips cost! - I negotiated with my vendor to get 20 tips for Bad Boy when I bought Bad Boy, because trying to buy the tips for Bad Boy would have nearly doubled my cost!

The whole shrimping thing has been such a fun adventure in lateral thinking / cross pollination. For example, just this week I bought stuff from and aircraft parts place, a lab supply vendor, an embroidery shop, and a memorabilia collector vendor.

I try to spread my investment out proportionally: some toward livestock, some toward systems and systems upgrades. Right now, I'm on a QA kick, designing my systems and protocols for QA. If you don't have QA and are automated, you are setting yourself up for spectacular failure one day - never a good thing.

Thanks for the offer, BTW - awesome! I am such a dumpster diver at heart....

Any budding mad chemists reading?? PM me...

[DKShrimporium]

Originally Posted by dbosman@msu.edu

They were originally a HEPA filter frame.

Let's hope it wasn't a discarded used filter cartridge from a laminar flow hood... eek!

[dxiong5]

Always interesting to see what you're up to. Sorry, what is "QA"?

[DKShrimporium]

Originally Posted by dxiong5

Always interesting to see what you're up to. Sorry, what is "QA"?

QA = Quality Assurance

Basically, the theory is that every method is a process. (For example, raising shrimp).

Any method can be broken down into a protocol of steps, each step of which can be benchmarked by objective criteria. You identify the steps and benchmark criteria, then you check each step for constancy over time to make sure your method remains the same.

[DKShrimporium]

Bad Girl and Big Kahuna are on their way to DK's Mad Shrimp World. Part of the QA program, along with recent Ca++ and Mg++ titration tests. With these tools, I will be able to ensure consistent, batch-to-batch levels of minerals in the water factory.

Bad Girl is 100-1000 microliter pipette. Big Kahuna a 1000 ml graduated cylinder. Biology is coo-el. Chemistry is fun (I prefer to think of it as Mad Alchemy).

The larger micro-tanks have arrived. Maybe I'll post some pics later of the drilling jig and how I drilled them for the mini-bulkheads.