Lysmata culture page

[FuEl]

Been rather busy with my experiments..just some larval photos I thought I should share.

Lysmata amboinensis zoea I

Note the tail has curled under the body after I killed it with formalin. Real irritating side effect of formalin.

[FuEl]

Zoea II. Note that coloration has started to take over.

Hard to take the whole animal..especially when it's through a microscope lens. Anyway..main morphological change is the stalked eyes.

Oh well..will add more pics soon..if the larvae don't die on me that is. Notorious for mass mortality around week 2.

[marinebetta]

Yo....smuggled some back to Oz? Nice work. Hope they do well....then the $$$ will flood in

[FuEl]

Yo....smuggled some back to Oz?   Nice work.  Hope they do well....then the $$$ will flood in     

Nah..not worth the risk..the broodstock already been here for awhile. My first batch not doing that well..today's day 9...although some reached zoea IV but today I checked survival..only around 48%. 2nd batch might do better as I'm currently doing another experiment to determine their diet. It does seem that immediate availability of phytoplankton after hatching plays a major role in the natural diet composition of L.amboinensis larvae. Not statistically tested yet though...that's where the headache will come..I hate statistics....

[FuEl]

Some photos on day 9..Think it's zoea IV now..

[FuEl]

Some of them held in a beaker.. so cute..

[FuEl]

Had some interesting find today..seems that early Lysmata larvae do consume phytoplankton. Those fed phytoplankton initially seem to be more tolerant of physical stress and they appear to be more active than those fed rotifers or Artemia straight after hatching. No scientific papers on this though..I might be onto something..

Scrapped the experiment on Day 3. Will be devising a more accurate one for statistical analysis to be possible.

Day 3 of flawed experiment (no replicates for control, need more individuals per replicate..only had 10 larvae per 2-L flask replicate)

1) Control (Unfed)- all larvae remained in zoea I stage..survival 80%

2) T-ISO fed at concentration of 30750 cells/mL

Replicate 1 = 100% survival..all in zoea I

Replicate 2 = 100% survival.. half in zoea I..half in zoea II

Replicate 3 = 100% survival.. 9 in zoea I.. 1 in zoea II

Tested T-ISO concentration in replicate 2.. declined from 30750 cells/mL to 18000 cells/mL. Active ingestion seems highly possible. Replicate 2 was directly under light..microalgae might have increased in concentration during the photoperiod. Replicates 1 and 3 received less light.

Next experiment will be using higher microalgae concentration. Hoping to test 3 species..T-ISO.. Tetraselmis (the species used by Wakiki aquarium in Hawaii).. and Chaetoceros. Hope all goes well..

[damienkee]

wow! u r the champion....

[FuEl]

wow! u r the champion....

Nah...just real determined to make some breakthrough with this species and hopefully shorten their larval duration to less than 2 months...as in captivity for speculated reasons they delay metamorphosis till 3-4 months..most die before reaching settlement. Many scientists speculate it to be possible. Mainly they attribute it to reasons like aeration trauma, tangling with debri/other individuals and nutrition. So I'm just working on ways to reduce these 3 main causes of mortality. Now I found out that they can reach zoea II on phytoplankton, guess it more or less shows that they can consume phytoplankton actively. Just left to test which algae species is best. Going to try 2 types of system design next. One is an recirculating upwelling system with overflow..another is a modified static kreisel system..using air to circulate the water via surface movement..with a central bottom drainage.

[damienkee]

Nah...just real determined to make some breakthrough with this species and hopefully shorten their larval duration to less than 2 months...as in captivity for speculated reasons they delay metamorphosis till 3-4 months..most die before reaching settlement. Many scientists speculate it to be possible. Mainly they attribute it to reasons like aeration trauma, tangling with debri/other individuals and nutrition. So I'm just working on ways to reduce these 3 main causes of mortality. Now I found out that they can reach zoea II on phytoplankton, guess it more or less shows that they can consume phytoplankton actively. Just left to test which algae species is best. Going to try 2 types of system design next. One is an recirculating upwelling system with overflow..another is a modified static kreisel system..using air to circulate the water via surface movement..with a central bottom drainage.

bro, r u a scientist? y wat u say I catch no ball!

but u r really great! wish u all the best!

[FuEl]

Hmmm..my second batch of larvae reached zoea III stage. The uropods (segments of the tail) have formed. Second batch doing better than my first batch. Fed them more heavily on T-ISO and rotifers besides the staple Artemia nauplii. So far 2nd batch already 8 days old..survival about 80%. My first batch survival on day 9 was only 48.6%.

Anyway..picture of the tail of a zoea III larvae.

[FuEl]

Fine hair-like structures (not sure what you call them) on the appendages seem to assist in some filter-feeding activity during early stages. Just a personal observation.

[damienkee]

bro, any update?

[FuEl]

bro, any update?

Both batches were cultured in simple rectangular tanks. Will be moving on to upwelling design after I gain some experience with these fellows first.

2nd batch which was going well kinda crashed due to my mistake of taking salinity for granted..it was at 41 ppt. Only checked it after I changed water..most of larvae died to salinity shock and I kinda overfed them on that day too. Tangling with dead Artemia also killed most of them.

Anyway on the bright side the 1st batch is doing well. Salinity around 38 ppt and I'm bringing it back down to 35-36 ppt over 1-2 days. 1st batch is 17 days old as of today. Mortality has stabled with survival just over 30% so far. Zoea V stage now I think.

[FuEl]

Hehe...came out with a better larval rearing system..similar to "kreisel" systems..

Water gets pumped into the carboy from below. Overflows back to sump in the black tube. Just left to get the appropriate size mesh for the overflow and prey-collection bag so I can sieve out the live prey and replace with enriched ones.

[FuEl]

Guess which crustacean does this monster larvae come from?

[FuEl]

21 days old..transferred all 46 of them into upwelling carboy. They are able to eat minced squid meat already..

[damienkee]

wow! so excited!

[FuEl]

wow! so excited!

Upwelling with overflow was good idea. Enabled me to filter out all leftover Artemia and replace with newly hatched and enriched ones. Maintain better water quality. Bad news is that after the first night of the system survival drop from 26% down to 8%. Most got stuck at the overflow although it was meshed and flowrate was slow. Did'nt see such a problem coming since they looked fine for the 5-6 hrs I observed them in the system. Now got air current blowing at the overflow to stop any remaining larvae from gathering there. Sigh... Oh well..at least now learnt how to counter it..

[damienkee]

oh! sad to hear tat... but keep it up!

btw, if any new hatch, would u mix them together v the old 1? or u start in new tank?

[FuEl]

Air current did'nt work. Sigh so much for upwelling and overflow..after 2 days from 46 larvae become 4. Culled the remaining survivors. Most still died at the overflow although the overflow was only dripping rate. Happened only during lights out. They might have moved to the surface at night since most zooplankton do that. That's probably where they get stuck with surface tension near the overflow. Will be lowering the overflow to mid water and connecting it to a larger sieve. Hopefully that solves the problem.

Won't be mixing new and old batch. Alot of factors like disease and cannibalism to consider. They will eat each other if they can.

[damienkee]

can stop everything at night? then mayb the rate of die will reduce!!!!

[FuEl]

Modified the overflow. The exchange rate is only 15L/hr. Just put in 50 larvae that are 1 week old. So far looking ok..hope tomorrow the same deaths don't occur. Oh well..will have enough larvae for experimentation..the batch i took them from had around 850 larvae..

[FuEl]

Meet JarJar..my oldest larvae at 30 days old. Sole survivor of the previous and unfortunate freak overflow deaths. So named as it is now cultured in the safety of a floating 60ml plastic jar. Water, air and food exchange done 3 times a day. Special treatment..

[FuEl]

The clearest side photo I could take of JarJar. It keeps tumbling around..hard to take a steady pic..