[rogersb]

I have been keeping tangs for a couple years now but never had any success with breeding because they have all been too young until recently. My spathodus began displaying last week and on sunday, the fourth, my female was holding. I want to strip her and was thinking about waiting until the 18th. This should be about the time she passes the fry to the male. Will it hurt the fry if i strip them that early? Should I wait longer? I dont' want to let them spit in the tank because if my tropheus don't get the fry then my leleupi surely will. What do you guys think?

 

[Darkside]

You can strip them then, or you can wait and strip the male. Trust me my gobies manage to pass their eggs off in an aquarium full of comps and synodontis mulites, so the transition should be fine. I used to strip me female gobies about the 10-12 day mark and toss the fry in a tumbler I haven't lost one yet. Though now I prefer to strip the male at a later period, since my tumblers are full of other goodies. :fish:

 

[Dave]

Let the female pass the fry to the male. After the male has had them for 10 days you can strip with no issues. IME I would wait for the male to start chasing the female in an attempt to give the fry back again. At this point I would strip and the fry were always fully developed.

 

[triscuit]

I always strip my Eretmodus males because the females are stressed already (egg production, attention from the male, etc). It allows the fry to fully develop, so they are hardier and ready to transition to food. My males eat during holding, so I think the fry get used to nibbling on fish food prior to release. Other fry (cyps, eg) seem to take a day or two to realize that crushed NLS grow is edible.

 

[rogersb]

Sounds like a plan, I'll strip the male a little later, let the female have a break. Thanks.

 

[24Tropheus]

Hate to be an anti stripping pain but why not put the male in a tank on his own with lots of cover for the released fry?

 

[Dave]

Hate to be an anti stripping pain but why not put the male in a tank on his own with lots of cover for the released fry?

I personally would not split up a mated pair of gobies. Besides, the stripping is not difficult.

 

[24Tropheus]

It is I think not the difficulty of stripping the male thats the prob. (well better than stripping the female for sure) Happy that it is easy to do. Its also easy to re introduce a single male to females for sure after stripping. The prob with stripping these guys is not with how well you will do with the adults but with how well the young will do with the next guy, when they come to try and breed them.

 

[Dave]

The prob with stripping these guys is not with how well you will do with the adults but with how well the young will do with the next guy, when they come to try and breed them.

There is absolutely no evidence that stripping has any impact on future breeding. I have heard a few stories, but they were always second or third hand, and had no way to be verified. Besides, we are talking about stripping fully formed fry.

 

[triscuit]

Male gobies forget their paternity quickly: I've seen my males chase newly released fry when I let them be. Another hobbyist separated the male and within a two hour period the male spit... and then ate all the fry.

 

[24Tropheus]

"There is absolutely no evidence that stripping has any impact on future breeding. I have heard a few stories, but they were always second or third hand, and had no way to be verified. Besides, we are talking about stripping fully formed fry."

Try this?
http://www.behav.org/IEC/default.php?pr ... num&id=569

 

[24Tropheus]

Loss of imprinting is immediate I think.
Loss of other behavior would take generations to show as the none selected for genes are lost.
No wonder no one has proved it either way?

 

[Dave]

Nice abstract for a poster, which is of course not yet peer reviewed. In addition, it is a test for cross rearing, not stripping fully formed fry. I would agree that cross rearing could have an impact on mate selection. This would imply that it was not the stripping, but the rearing that resulted in the change in preference. In addition, we are talking about biparental mouthbrooders, which may have a different "imprinting" than maternal mouthbrooders.

Loss of imprinting may or may not be immediate, I do not believe that has been established in the case of stripping either. Again, we are talking about stripping fry that have been reared by the female and then passed to the father for another 10 days, not tumbling eggs. This generally results in ~20 days of mouth brooding. Until a time point study of stripping is done, it is all conjecture and anecdotal evidence.

 

[24Tropheus]

True but if cross rearing has an impact on mate selection, imprinting must be happening?
We have no idea of when imprinting happens though.
As for peer review, its been going on so far for a year or so.
The study is already quoted as a reference in other papers.
Thats how I stumbled on it. Before it was published.

Please keep in mind there is no way of proving Angel fish loss of fry care generation on generation but we can see the results of generations of rearing of eggs and fry away from the adults?

"study of stripping is done, it is all conjecture and anecdotal evidence."
Study is well advanced on this I hear. Results though will prob not be published.

 

[triscuit]

Heck, I've been working on my current research for two years, have talked at professional conferences and also have a prize winning poster on the subject: but it will not yet pass peer review. :? Research is a messy, unpredictable, time-consuming beast that can turn sour in an instant. So, a promising start is grand, but the peer review process is there for a reason... too bad that pharmaceutical companies have bypassed it! :roll:

Back to fish: I have generations of cyp and goby fry that were stripped at 21 days whom are breeding and releasing in mine and other hobbyists' tanks. Short term effects are not evident. My method of stripping does not involve any contact with the fry: they see an open mouth and they run for it. It's pretty hard to get them out if they don't want to come. It is impossible to comprehend what if any imprinting affects this would have. So, as far as the fry are concerned, mom has finally opened the door for them. My un-researched gut instinct is that the fry do register the difference.

 

[Dave]

One aspect that I never see analyzed is the impact of raising a much larger percentage of fry to breeding age, as compared to in the wild. It would not be unusual for someone to raise 90% of fry to breeding age, something that likely never happens in the wild. How can we be sure that this isn't a factor in these studies?

As for imprinting, I never said it didn't occur, you are assuming stripping makes the fry bad parents, and I have not seen any evidence to support this conclusion. The study you are pointing to says nothing about being bad parents, just that their mate choice is altered. Just because one aspect of breeding is altered does not mean all aspects are changed, or even can be. You cannot make that leap with the evidence presented.

I would like to see the publications that you are referring, either a link to the publication, or the journal reference would be fine.

 

[24Tropheus]

Goby-fry that have already made the 'swap' from female to male may have got their imprint and there is no additional breeding care once the male drops them, little chance of messing up imprinting if you strip late.
Still do not understand why you would want to strip a male Goby though, when a small tank with lots of cover would do fine for fry protection.

Cyps are among those that release and don't take back; it's impossible for a female Cyp to take back the fry, no imprinting, no maternal care after release, hence few if any effects at all when you strip Cyps.

The theory is: that stripping allows fish to reproduce that would not have successful spawns in the wild. Why breed with fish that have a lack something that should be in their behaviour? Spitting the fry into a safe environment being a key skill? With Cyps I understand this is to sycronise the release with other females?

Why not select here?

Hey I just thought are we talking about Spathodus erythrodon or marlieri?
Ones supposed to be just a maternal mouthbrooder? :lol:

 

[Darkside]

I have a 1 male that breeds with 3 females. He spawns with all 3 females, but will only accept the switch between 1 of them. The other 2 females have both produced viable fry, but would end up holding the entire duration (and have) without my interference.
As for imprinting... The mechanics behind imprinting is poorly understood and I've seen no evidence, either published or in my own experiences that would indicate that stripping the male has any effect on the fry.
In North America we strip the fish, I mean how is the fully formed little juvenile going to recognize the difference between being spit out intentionally and being spit out because of human intervention? The process would, in practice, be very similar. In Germany (and I suppose the rest of Europe) stripping is frowned upon, but that seems to be a difference of opinion.
I don't see why we'd bother to exhibit some sort of "selection" in our aquariums when its obvious that we can't provide our fish with a environment that really does emulate the lake. Phenotype is one part genetics and one part environment and until we more clearly understand the relationship between the two in these fish arguing about it is sort of a moot point. I don't think that gobies are a model organism for genetics but I do know that there have been studies using Eretmodus cyanostictus as the model animal where genetics has been linked to monogamy.

 

[Dave]

The theory is: that stripping allows fish to reproduce that would not have successful spawns in the wild. Why breed with fish that have a lack something that should be in their behaviour?

I do not think that this is a true statement. Though it might allow a fish to produce young that it would not do in the wild, the reason for stripping is not predicated on this. Frontosa are stripped because many are notorious for not holding for term in the aquarium. We don't know why they do this, only that it is common, but this does not mean that these fish would not spawn naturally in the lake. There a many animals that are known to be very difficult to breed in captivity, so we should not be surprised when this occurs.

There are several other reasons for stripping. One is so that the female will become conditioned to breed again much earlier. I do not subscribe to this practise. The another is to ensure that you recover all of the fry by removing them from the holding fish just before release, though some do it earlier in development than others. Finally, removing the holding fish may not be practical due to reintroduction aggression, like in Tropheus. I always stripped my females just before spitting, because my group of Kazumbas would never allow a fish to be reintroduced after a week or more of being out of the community.

Spitting the fry into a safe environment being a key skill?

I understand that this is one idea in Europe, but frankly I do not see this being a very "natural' event when the fry are trapped in such a small enclosure. My experience is that losses are excedingly high when we allow for "survival of the fittest".

With Cyps I understand this is to sycronise the release with other females?

Perhaps, but then I have never seen a home aquarium even come close to mimicking a true Cyp school. I have seen some cyp groups that spit their fry and leave them alone, and I have seen groups that must be separated.

Why not select here?

Because this is just as artificial in the aquarium as stripping, and not all mouthbrooders take their fry back after release.

Hey I just thought are we talking about Spathodus erythrodon or marlieri? One's supposed to be just a maternal mouthbrooder?

Based on S. erythrodon being very common in the hobby, that is where I am putting my money.