Almost everyone wants LMB as the normal accepted stocking practice for stock ponds, but many have concerns of overpopulation issues and amount of time commitment for management control.

Is there a scientific explanation as to why existing technology with triploid grass carp cannot be archived with LMB, or strictly a business risk decision?

http://www.wvu.edu/~agexten/aquaculture/triploid.htm#Development
“……….. most fishes, are diploid. They possess two sets of chromosomes (one from each parent) and are capable of sexual reproduction. Triploid fish, however, have three sets of chromosomes and are incapable of normal sexual reproduction and the production of viable offspring. …….
Triploid fish were first produced in the United States in 1979 as inter-specific crosses between female grass carp and male bighead carp Aristichthys nobilis (Molone 1982). These fish contained an extra set of chromosomes and were incapable of reproduction, but were hybrids of the two species and not true grass carp; successful plant control was limited. Later, triploid grass carp were produced in-transpecifically, by physically shocking fertilized eggs with heat, cold, or hydrostatic pressure; this stimulated the retention of a set of chromosomes that would normally be expelled during cell division (Clugston and Shireman 1987, Cassani and Caton 1986, and Allen and Wattendorf 1967).
Physical shock techniques induce polyploidy with apparent yields of 100 percent triploids (Cassani and Caton 1980). Because of this high success rate, this technique is being used to produce large numbers of fish. Concern exists, however, that induced polyploidy could result in the production of some reproductive grass carp (i.e., diploid or reproductive triploid fish). Consequently, triploidy in each must be verified prior to stocking. Ploidy is most often determined by a Coulter Counter, which electronically measures the volume of a red blood cell after the cell membrane has been chemically removed (Allen and Wattendorf 1987, Clugston and Shireman 1987). Since triploids have larger red blood cells (and nuclei) than diploids, cell size differences are used to confirm triploidy (Allen and Wattendorf 1987)."

A triploid grass carp sells for $10-$12 each, I am assuming the cost is so much based on all those big words and testing described above.
There is a market for the grass carp because typically you only buy a small handfull. I dont think I would stock my pond with triploid LMB for $10-$12 each.

Journal of the World Aquaculture Society
Volume 35 Issue 1 Page 46-54, March 2004

Artificial Propagation and Induction of Triploidy in Largemouth Bass Micropterus salmoides and Ploidy Discrimination using Erythrocyte Length

J. Wesley Neal11Department of Zoology, North Carolina State University, Campus Box 7617, Raleigh, North Carolina 27695-7617 USA, Diana M. Neal11Department of Zoology, North Carolina State University, Campus Box 7617, Raleigh, North Carolina 27695-7617 USA, Richard L. Noble11Department of Zoology, North Carolina State University, Campus Box 7617, Raleigh, North Carolina 27695-7617 USA, Michael V. McGee22Caribe Fisheries, HC-03 Box 22972, Lajas, Puerto Rico 00667 USA1Department of Zoology, North Carolina State University, Campus Box 7617, Raleigh, North Carolina 27695-7617 USA 2Caribe Fisheries, HC-03 Box 22972, Lajas, Puerto Rico 00667 USA

Abstract

We describe an artificial propagation procedure and simple ploidy discrimination techniques using erythrocyte major axis length for largemouth bass Micropterus salmoides. Hormonal treatments of 5 mg/kg of carp pituitary and 50 μg/kg of leutinizing hormone-releasing hormone (LHRH) produced viable gametes in 21-24 h, and triploidy was induced using a pressure treatment of 563 kg/cm2 on embryos for a 1-min duration exactly 5 min following fertilization. We produced about 500 fingerling triploids and about 500 diploid controls, and verified genetic status of a subset of each group using flow cytometry. Erythrocyte length was measured for 10 known diploid and 10 known triploid individuals. Remaining fish were internally microtagged with group-specific tags and mixed to test the model. We developed ploidy discrimination intervals based on the 99% confidence limits of mean erythrocyte length (MEL, N = 25 erythrocytes) for individual fish, which were 14.43-16.66 μ.m for triploids, and 10.23-13.62 μm for diploids. Logistic regression provided the discrimination model: Ploidy status (±) = -196.16 + 13.97 x MEL, with positive (+) outcomes considered triploid. Both discrimination techniques were 100% effective at differentiating ploidy of the 22 microtagged largemouth bass recollected from the mixed population. We did not observe a significant change in erythrocyte length as fish size increased, indicating that erythrocyte length is an accurate predictor of ploidy for all sizes of largemouth bass.

Texas has produced triploid LMB and stocked them in a least 1 experiential lake ( not a growout pond but a lake of some size with other fish).

TPW used triploid Fla. LMB in several of its studies which are not available to the public. Several of the studies on these matters are still ongoing in TX lakes and more info will soon be available.

One of the most interesting bass stocking experiments going on right now is Texas Parks and Wildlife Department's introduction of triploid largemouth bass. These are bass that have three sets of chromosomes instead of two (hence the term triploid), so they are effectively sterile and will not reproduce. Triploidy, as it is called, is often used in fisheries management to produce sterile fish. The two most common methods of producing triploid fish are by heating the eggs or placing them under high pressure after they are fertilized; the resulting fish that hatch from these treated eggs are triploid and unable to reproduce. The hope is that bass that do not reproduce and do not spend the time and energy necessary to spawn will grow faster and larger than bass that do spawn. This technique may also offer the opportunity to stock a genetic strain of bass that, because they are sterile, will not interbreed with the existing bass population and change the genetics of it. The jury is still out right now, and this is definitely an experimental stocking at this stage, but the possibilities exist for producing big bass and refining bass management using this technique.



Triploid largemouth bass, Micropterus salmoides, were produced by using hydrostatic pressure treatments five minutes after fertilization. Treatments ranged from 4,000 p.s.i. for 3 minutes to 8,000 p.s.i. for 1 minute was best, yielding 100% triploids and a relatively low mortality. Contributors: Gary P. Garrett, Heart of the Hills Research Station, Texas Parks and Wildlife Department, Ingram, TX, 78025, United States
Matthias C.F. Birkner, Department of Wildlife and Fisheries Sciences, Texas A & M University, College Station, TX, 77843-2258, United States
John R. Gold, Department of Wildlife and Fisheries Sciences, Texas A & M University, College Station, TX, 77843-2258, United States

Lake Balmorhea - 2005 Survey Report - A special research project included the introduction of triploid Florida largemouth bass from 1999 through 2003. Genetic analyses demonstrated that some cross-breeding was occurring between Northern and Florida largemouth bass, indicating that not all of the stocked Florida largemouth bass were sterile.

Sweetwater Reservoir

Triploid Florida-strain largemouth bass marked with coded wire tags were stocked from 1996 to 2000 as part of a research project to investigate whether it was possible to create and maintain a non-reproductive, trophy Florida-strain largemouth bass fishery while maintaining high catch rates of naturally reproducing fish. Due to the poor survival of the marked fish this project was terminated in 2001.

Good information guys.
It seems to me that there would be a good economic incentive to produce triploid LMB on a commercial basis for small ponds if the advantages of no reproductionn was well known.

A simple stocking "ladder" in a small pond of 10 sterile LMB on an annual basis, would not be cost prohibitive, if there is enough demand to warrant acceptance by hatcheries.

Another one of the professors here did a study comparing diploid and triploid rainbow trout in ponds in western South Dakota. As most readers probably know, South Dakota gets the full range of temperatures, and the pond surface waters can get warm at times in the summer. Thus, it's not always prime habitat for trout from a temperature perspective.

Well, the triploids did not perform as well as diploids in those ponds. That was strange, as they did not develop gonads, and no energy thus went to reproductive products. It turned out that is was a functional problem. The triploid red blood cells were larger than diploid red blood cells because of the extra genetic material in the nucleus [I'm NOT making this up!! :)]. As a result, the triploids actually could carry less oxygen in their bloodstream because there were fewer red blood cells in their body. In waters of the correct temperature, the triploids would out-perform the diploids. In waters with marginal habitat, the stressed triploids did worse than the diploids.

I'm not sure exactly how this relates to LMB, but I figured some of you would find it interesting.

So the moral to the story is....? Sometimes you get an unexpected bad with the expected good?

when screwing w/ genetics......

expected good?:


unexpected bad?:

The good news is most of the time the bad, being non-viable, goes extinct.

Well, Dr. Bruce, the morale of the story might be:

1. It all depends....
2. Never be overconfident when it comes to fish....
3. Never count your chickens before they hatch....
4. There are a million ways to kill fish....
5. It's the habitat, stupid.... (hear the Bob Lusk voice there?)....

I'm sure there are many more such morales, morels, or others.

Or, in my case, there are ways to kill a million fish.

Personally from my experience the reason some things aren't done is just because private producers aren't willing to take a chance or aren't imaginative enough. I can think of several profitable things that producers could do but just won't. For example: With the right promotion Talapia could be a gold mine for northern producers for algae control, but after beating some of them over the head with the idea they just won't do it. I can't think of a better market than producing a fish that dies annually and has to be restocked. Adn a fish that is so forgiving and easy to produce! And considering it is a viable alternative to chemicals, and would be a solution to the number one complaint of pond owners (filamentous algae aka pond scum) it's a no brainer. But what do fish producers say when I tell them about it? "I'm not interested."

Another example: I sell trophy size (broodstock size) trout for close to, and up to, and over $100.00 a piece to taxidermists and replica makers. Before I decided to do it myself I again beat some fish producers over the head trying to convince them there was a lucrative marker for worn out broodfish that many of them just discard. Do you think any of them were interested? NO!

I also see producers in my area selling the same ol' fingerlings etc. but no larger fish for remedial stocking or into established ponds. There is a big market for those larger fish that can get premium prices. Are any of them interested in this market. NO!

And then there's those God awful hybrid bluegills everybody pushes. My phone has rung off the hook with people that are looking for REGULAR strain bluegills. Rare is the producer that sells them around here! I already have a fish supplier that says they will take ALL of the bluegill I can produce this year. The supplier says they just can't find them!

So until someone that is a true entrepenuer, or is willing to take risk to be a leader, most fish producers will sulk in the same old in the box thinking and producing.

I'm sorry to say but many of the fish producers I have met are not very opening minded. Maybe all that time near the water has rusted their brains.

That said, adding male or female hormones to feed before the fry become male or female is the most economical and most sure way to produce males and females from the literature I have read. Once the fish are large enough for consumption, the hormones will be long gone out of their system. I hope to produce all male smallmouth bass this way in the future for retail store display aquariums, as I was told the females have serious problems with egg absorption. All the literature I have seen says there is no difference in size and growth among the sexes in smallmouth bass.

This is interesting research that could have ramifications for a long time. To grow bass that had no breeding pressure. They might have to make a new column in the record books for Triploid LMB. I agree with Mr. Baird on a lot of things, from personal experiance it is very time consuming and laborius project to over-winter Tialpia. However a population of people in North Country could benefit greatly from someone taking a chance on Tilapia production.

If we can make Triploid bass, what about Triploid crappie, then anyone can have crappie without fear of overpopulation. You could also treat different species as a put-and-take. Put in 500 crappie in a small impoundment let them grow up and then take them out. Start over again and you have a industry that keeps going. This could be heady stuff here. Someone just has to take a chance.

Chad since you asked - we are the cutting edge.

http://www.pondboss.com/forums/ubbthreads.php?ubb=showflat&Number=13896&fpart=1

Comparisons of Triploid and Diploid White Crappies
GLENN R. PARSONS

Freshwater Biology Program, Department of Biology, The University of Mississippi, University, Mississippi 38677, USA

Abstract.—I produced triploid white crappies Pomoxis annularis in the laboratory by subjecting stripped eggs to 5°C for 90 min. This treatment produced triploids on three out of seven attempts, yielding 92%, 93%, and 100% triploids. I compared several hematological characteristics of adult triploid and diploid white crappies. Triploids had significantly lower concentrations of circulating red blood cells and hemoglobin than diploids but their red blood cells had significantly greater volumes and hemoglobin contents. Diploids had significantly higher gonadosomatic indices. Diploids and triploids did not differ significantly in heart weight as a percentage of body weight or in standard metabolic rate, active metabolic rate, or critical swimming speeds. Despite the hematological differences, nonreproductive triploid white crappie adults appear to be as fit for survival as normal diploid fish.


Comparison of Triploid Hybrid Crappie and Diploid White Crappie in Experimental Ponds
GLENN R. PARSONS

Department of Biology, The University of Mississippi, University, Mississippi 38677, USA

KEITH MEALS

Mississippi Department of Wildlife, Fisheries and Parks, 310 Shoemaker Hall, University, Mississippi 38677, USA

Abstract.—We crossed female white crappies Pomoxis annularis with male "black-stripe" black crappies P. nigromaculatus to yield hybrids possessing a distinct coloration that may serve as a natural tag when fish are introduced into existing crappie populations. Eggs of these hybrids were cold shocked to produce triploid hybrid crappies. In three spawns, the black stripe was expressed in 100% of hybrids that were not cold shocked and 85% of hybrids that were cold shocked. Coldshocked hybrids were 95% triploid and 5% diploid. Triploid hybrids bearing the black stripe and diploid white crappies without the black stripe were stocked into experimental ponds for growth and survival comparisons. There were inconsistent differences in growth, body condition, and survival of triploid hybrids and diploid white crappies after 1,151 d in ponds, but the gonads of triploid hybrids were consistently smaller than those of diploid white crappies for each sex. No reproduction was observed in ponds with triploid hybrids, whereas reproduction occurred in ponds with diploid white crappies. Although better growth and survival were not consistently observed among triploid hybrids, the lack of reproduction may be an advantage over diploid white crappies in the management of small impoundments.

Evaluation of F1 Hybrid Crappies as Sport Fish in Small Impoundments
MICHAEL L. HOOE and D. HOMER BUCK

Illinois Natural History Survey, Sam Parr Biological Station, Rural Route 1, Box 174, Kinmundy, Illinois 62854, USA

Abstract.—Growth and reproductive characteristics of reciprocal F1 and F2 hybrid crappies–white crappies Pomoxis annularis × black crappies P. nigromaculatus–were examined to determine if hybrids are better suited for stocking in small impoundments than their parent species. Relative weight gains of the reciprocal age-0 F1 and F2 hybrid crappies were not significantly different (P = 0.55), but the relationship may have been masked by differences in initial sizes of the test fish. Second-year relative growth rates of both reciprocal F1 hybrids were significantly greater than growth of either of the parent species and, with one exception, than growth of the reciprocal F2 hybrids. The reciprocal F1 hybrid crappies were capable of backcrossing with their parent species, and both reciprocal F1 hybrid male crappies had viabilities equal to those of their parent species. Egg viability for the F1 hybrid black crappie female × white crappie male appeared equal to that of the parent species and greater than that of its reciprocal hybrid. Recruitment in ponds was highest for the pure species, intermediate for the F1 hybrids, and lowest for the F2 hybrids. This study confirmed that F1 hybrid crappies may offer a viable alternative to stocking parent species in small impoundments, the F1 hybrid white crappie female × black crappie male being preferable to its reciprocal hybrid. We recommend that hybrid crappies be used only on an experimental basis pending a more thorough evaluation of the incidence and effects of backcrossing with parent species.

Chad,

No need to produce them or overwinter them. There are plenty of Talapia foodfish producers that would jump at the chance of selling their Talapia at prices more than they get for foodfish production. One would simply need holding ponds in the spring and could sell them out by the middle of the summer. And of course a good size hauling truck would be a plus. I see used ones for sale occasionally on an Aquaculture site. Man I wish had the funds sometimes! I have so many ideas but it takes money to make money! But I'm working on it!

The niche markets I am pursuing now are lucrative but I'm limited by the number of ponds I have and limited acreage to put in more.

I question the practice of interceding in the genetics of wildlife in general.

I see your point Dwight but it may be more common than you think. Man has been selectively breeding and interbreeding animals since before Christ.

I have to chuckle when I see people complain they don't want us to genticially engineer food crops. I want to say where have you been? It's been done for decades.

That said I wasn't referring to you specifically. I respect your opinon that we shouldn't interfere.

I have to agree with Cecil here. Genetic engineering in its most basic form is just selective culling.

The only real risks are when you narrow the gene pool to the point that an organism is prone to disease or infection. Even in that case, most times you'll see a limited number survive such an outbreak and continue on the "strain" with a regained resistance.

Isn't the whole "survival of the fittest" thing nature's own way of genetically engineering organisms?

It isn't selective breeding the I question. Selective breeding is just natural selection with a little encouragement. Producing a sterile breed of Bass through gene manipulation is more than selective breeding to my way of thinking.

I am no environmental wacko, though I think there is a lot to be said for the natural order of things. I wouldn't want any of those sterile Bass exuding bad karma in Bremer Pond.

As far as I know, production of triploids is not 100% effective. I think only 98% or so of grass carp end up triploid, which is why they have to be individually tested and certified before release from the hatchery.

If the same goes for LMB and Crappie, then what is the point of triploid production. The equipment used for ploidy testing costs around $40K.

Triploid grass carp?
Sterile tialpia (triploid?) for the seafood market?
Bad karma?
What am I missing?

Thanks Todd, I thought it to be more for economic reasons than science.

Maybe I'm wrong but if a producer already had the equipment he was using for grass carp and he was able to individually market the bass and crappie as 100 percent triploid the investment would be minimal compared to the potential profit. Even if one had to go out and buy I still think it would be profitable. All you need is half the marketing skills of Ken Holyoke and you're in business. After all if Ken can make people think his green sunfish bluegill hybrids are the Holy Grail why couldn't someone market feed trained triploid bass and crappies as a way to open up a whole new market?

Todd you have forgotten more than I will ever know about raising fish, but I guess I see this as a great opportunity for the first one to market it, and be known for supplying these fish. It's a risk sure but anything worthwhile is.

And it's not like triploidy is rocket science. Most rainbow trout produced in this country are either sterile females or triploids. Most producers buy the eggs from farms that specialize in this kind of thing rather than go to the trouble and expense of keeping broodstock around.

You know Bobby Glennon don't you Cecil? He would be the man to do this triploid thing for all of us, because he has the equipment and resources. He has raised some hybrid crappie and not sure but I think he has tried some triploids as well with low fry survival rates as a result. He even crossed a bluegill with a bass, resulting in some little "blass!" Maybe you should ask him how those experiments went so we can all learn from it, and find out if he gave up on triploids or not, and why. I remember speaking with him about it, but he always got slammed in the spring and probably was not able to see it through properly.

Fish farmers in the business are working overtime during hatching/spawning season. All of the pipe dreams that resulted from January/February cabin fever have vanished into thin air by the time the spring thrashing has commenced. Maybe the hobbyists or researchers can come up with with a triploid, develop the protocol, work out the bugs, study the red blood cells, and wait for the final verdict to come in. Then sell that varnished idea to a fish farmer for production.

Maybe we reserve this type of genetic manipulation for grass carp. I've seen some wicked mutations in grass carp. What are the implications with sportfish?

Wow, Todd!! I assume you are talking about a Coulter counter? 40K?? I had no idea. So much for the ivory tower problem, eh?? Cripes. Thank you.

Yes I do know Bobby and he has told me about his experiments. But as you say he has other responsibilities and I don't think he was able to give it the attention it needed. I do know as you probably do that Malone and Sons, whom he works for, were the pioneers in tripolid grass carp.

That said I think the other route of changing the sexes of fry or sex reversal may be the way to go. Since my fish are not raised to be eaten, I will be experimenting with the hormone treatments in the future but I will not produce them for resale. I also will not treat any fish in any water that would leave my farm for several months.