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pirate perch culture

Started by Guest_Pirateperch_* , Mar 13 2010 09:48 PM

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197 replies to this topic

#21 Guest_gerald_*

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Posted 26 March 2010 - 10:53 AM

Huh? I never knew it was possible for unfertilized eggs to divide.

[quote name='centrarchid' date='23 March 2010 - 12:21 PM' timestamp='1269361277' post='74251']
They are not fertile (no male present) despite some going through some early cell divsions. [quote]

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#22 Guest_centrarchid_*

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Posted 26 March 2010 - 12:24 PM

Gerald,

Water exposure of eggs alone can often initiate egg activation but no hatch likley since quality of activation may be inadequate to promote hatch. Other factors can stimulate activation better resulting in hatch without involvement of paternal DNA. I use latter in my work to create gynogens. Controls (negative controls) used for the process are not exposed to sperm but cell division does commence in most eggs although hatch does not.

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#23 Guest_Pirateperch_*

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Posted 27 March 2010 - 09:02 AM

Good news and bad news regarding my efforts to produce pirate perch indoors. This morning I collected 24 eggs that fell out of the nesting material and took them into the local university fish lab so I could use their microscope.

Bad news first.

Only about 50% of eggs I collected from a brood produced two days ago contain developing embryos. Just 13 are alive with hearts beating.

Secondly, my water flea culture (Daphnia magna) appears to be in the process of crashing. Centrarchid pointed out the "ephippia" in the image and the black patches on most of my adult water fleas. He says they are no longer reproducing parthenogenically, which is needed for sustainable harvest. He says start new cultures ASAP.

Good news is I have a lot more than 13 developing embryos. See photograph below. When looking at image, you could see hearts of the pirate perch embryos beating. Egg diameter of this clutch averages just under 1.8 mm. To the lower right of the pirate perch is one of the "ephippiums". Apparently when the pirate perch are fighting, scales are nocked off from time to time. The males do spend a lot of time bitting other fish.

PIRATE PERCH EMBRYOS 1.0x 2010 March 27 0800 001.jpg 265.3KB 5 downloads

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#24 Guest_Pirateperch_*

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Posted 27 March 2010 - 02:58 PM

Spelling adjustment must be made for previous post. Please replace "ephippiums" with "ephippia" which I think is proper plural for ephippium. I wonder if there is a market for such things. I could harvest a couple hundred pounds from a local lagoon with relative ease. Just a thought. It obvious how such a structure could be moved about by wind for dispersal.

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#25 Guest_Pirateperch_*

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Posted 27 March 2010 - 07:51 PM

I am setting up to film male pirate perch courtship. Before gettng started I noted to discrete male behaviors. Some males stay near breeding sight but stay out in open. A good example is shonw below. The same males seem inclined to challenge fish that approach them or nest site, especially other pirate perch. The white stuff the nest site.

IMG_0434.JPG 34.72KB 2 downloads
Other males hide within the nest site and frequently flutter their pectoral fins, often for several seconds at a time. They also will come out to challenge other fish that approach especially other pirate perch. Notice the males yellow under parts; all breeding males seem so colored.

IMG_0439.JPG 36.75KB 2 downloads

These picture shows how the females just sit tight and capture what ever edible comes by. In this case water fleas.

IMG_0435.JPG 29KB 2 downloads

IMG_0436.JPG 39.58KB 2 downloads

The last image shows tank being used to incubate pirate perch yet to hatch. Parents were in it until yesterday. Hopefully all tanks will go thru this sequence.

Attached Files

IMG_0438.JPG 42.09KB 2 downloads

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#26 Guest_Pirateperch_*

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Posted 28 March 2010 - 11:41 AM

The batch of pirate perch eggs I am monitoring are now between 3 1/2 and 4 days and still not hatched when incubated within a temperature range of 65 to 69 degrees Fahrenheit. I can see the little guys in the eggs with a magnifying glass and they appear to be developing. They must be fairly advanced when they hatched.

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#27 Guest_wargreen_*

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Posted 28 March 2010 - 03:28 PM

Cool, thanks for the updates.

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#28 Guest_Pirateperch_*

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Posted 29 March 2010 - 08:07 AM

Eggs are now 4 1/2 and 5 days old and still no hatch. Egg diameter on some appears to be increasing. Is this a prelude to hatching? They are still much smaller than unviable eggs of same clutch.

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#29 Guest_Pirateperch_*

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Posted 29 March 2010 - 08:13 PM

Looks like it takes about 5 days for pirate perch to hatch. From a distance they seem quite yellow. Average length is about 3.45 mm.

PIRATE PERCH PROLARVAE 1.25x 2010 March 29 2000 001.jpg 187.31KB 3 downloads

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#30 Guest_Pirateperch_*

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Posted 31 March 2010 - 06:54 AM

Following image of pirate perch 24 hours after hatching. Eyes becoming pigmented. They are much more active now. Tip of tail upturned already and rays appear to be developing.

PIRATE PERCH PROLARVAE 1.25x 2010 March 30 2000 001.jpg 196.86KB 2 downloads

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#31 Guest_Pirateperch_*

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Posted 31 March 2010 - 03:00 PM

Approximately 48 hours after they hatched lower jaws are visible and moving.

PIRATE PERCH PROLARVAE 1.25x 2010 March 31 2000 001.jpg 185.74KB 2 downloads

The second picture the blood can even be seen to flow through capillaries, not just heart and arteries. The faint speckling on tail area I think is individual blood cells. They are also assymetrical in respect to position of yolk.

PIRATE PERCH PROLARVAE 2.0x 2010 March 31 2000 001.jpg 132.38KB 2 downloads

I wonder how dad keeps from eating these guys. They move around a lot. He does not seem to eat water fleas very well.

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#32 Guest_gerald_*

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Posted 31 March 2010 - 03:34 PM

Are they staying in the poly floss? laying on floor? stuck to walls?
Watch and see if the male spits out any fry he slurps up, like Elassoma do.

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#33 Guest_Pirateperch_*

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Posted 31 March 2010 - 03:41 PM

Most but not all staying poly floss. Those leaving sit on bottom, no sticking to walls. Male does not appear to eat.

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#34 Guest_fundulus_*

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Posted 31 March 2010 - 05:16 PM

Your magnification isn't high enough to pick up individual blood cells in the tail in that last image. I'd guess that the speckling you mention (a series of grayish spheres often in loose linear order) is cartilage forming to define the caudal rays. Others probably know better than me.

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#35 Guest_Pirateperch_*

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Posted 31 March 2010 - 08:06 PM

Your magnification isn't high enough to pick up individual blood cells in the tail in that last image. I'd guess that the speckling you mention (a series of grayish spheres often in loose linear order) is cartilage forming to define the caudal rays. Others probably know better than me.

The movement of the "blood cells" was very obvious as particles following very specifc routes. The irregular rows are made up of the particles I am seeing. Their movement also appeared to be in time with heart beats. I would like to make a short movie of the action. If I am correct then we are likely to conclude the blood cells in such young pirate perch are very large. Also the blood completes a circuit between heart and body within a second or so.

Edited by Pirateperch, 31 March 2010 - 08:10 PM.

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#36 Guest_Pirateperch_*

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Posted 31 March 2010 - 09:02 PM

Fundulus,

The picture shows what I think is the route blood cells follow.

blood.bmp 1.06MB 15 downloads

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#37 Guest_fundulus_*

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Posted 31 March 2010 - 09:19 PM

Those would be truly monstrous red blood cells, it wouldn't take too many of them to fill the heart's chambers. What magnification are these images taken at? I assume that these larvae are ~6 - 7 mm long.

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#38 Guest_Pirateperch_*

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Posted 31 March 2010 - 09:31 PM

Blood is pretty dilute in terms of the "red blood cells". The heart is about twice as big as what picture indicates. It has two chambers in a strait line. When a chamber contracts it becomes difficult to see.

Lense of eye piece is 10x and larger image was made with 2.0x "objective" lense. I do not know what magnification of digital part is.

The larvae I think are just under 6 mm long. I can measure them tommorow to make certain. The scope can measure if correct magnification is known. Supposedly the microscope I am using can make video clips as well.

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#39 Guest_fundulus_*

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Posted 31 March 2010 - 10:05 PM

The reason I ask is because if I know the magnification, which is 20x from your description, I have software that can measure lengths in digital images with high precision. I'm curious to see how big those objects are that you see moving, which I don't doubt are truly moving. Hopefully I can do that by tomorrow night if my schedule doesn't get too zippy. Also, I'm curious to track down any fish hematologists; of course I've never met any, but what the hell, maybe one will surface when we need one!