Anyone for a round of-- Can you sex this zebra pleco?

[Barbie]

Everything helps at this point Ian, so thank you!

I keep them at 86 degrees, with high water turnover, now there are 8 of them in a 4 foot long tank, of 40 gallons. I feed live blackworms (but the fish were in this condition before I was able to find them, so that doesn't seem to be the cause, IMO), tetra color bits, NLS growth pellets, hikari algae wafers, frozen daphnia, cyclopeeze, spirulina flake, and basically whatever is in my hand at the moment. I only feed once a day, and there are no other fish in the tank with them. There are 4 caves of varying diameters that at least 2 of them use consistently, and another one uses occasionally. I did try to vent the second 5, and without some help to hold the container, a strong light and a magnifying glass, I couldn't see any noticable differences. I'm terrible at the whole fish perv thing I guess!

I've been told by a reliable source that the first group had a male or two in it, and it all seems up for debate at the moment. I no longer feel quite so disturbed about not being able to tell the difference for sure though ;). Thank you all for trying to help. I will probably just leave the 8 alone until I see some obvious spawning activity. Then I intend to move the "pair" into a tank of their own and see if anything happens in the remaining fish. At this point, I'm not too worried about setting up that second tank in any real hurry!

Barbie

[pleco_farmer]

Per Shane and Larry, the food supply changes with the rainy season. All sorts of new stuff comes down the pipe when it rains. During a two month dry season, I cut feeding back to every other day, sticking to frozen bloodworm and pellets. After the water change, feeding reverts to once a day, and then I slip in the treats. This has helped to get some groups in the groove. Drops in temp and conductivity are the primary triggers, but every little bit helps.

There are times when exceptional pairs will appear, and I will segregate them. Sometimes you just find a real productive couple, who breed at the drop of a hat. Otherwise, I am finding the best success with groups of five, 2M-3F. Maybe its a pecking order thing, give the females a choice of mates and get a little competition going. I did have a simultaneous spawn last month in one group, but this is unusual in my setups. Each group occupies a 2' X 2' X 1.5' section of a long plywood tank, so it might be tight. If a couple of groups are unproductive after six or eight months, I will also shuffle the members. But in our commercial setup, we are looking for randy breeders, so after two years, we can afford to sell off stubborn fish.

So, unless you are really aiming for volume, you might want to leave the group together. Tracking the lineage of the fry is a bit of a challenge, but after seven years, we are at the point where the majority of juveniles that we sell are F2. My orginal group of twenty F0 is almost intact, and some are spawning with F1.

BTW: What is correct way to label a generation that is the result of a F0/F1 spawn?

[pturley]

plecofarmer wrote:

BTW: What is correct way to label a generation that is the result of a F0/F1 spawn?

If it's fry to parents it's a "backcross". In captive breeding this is usually not considered a good thing to do. Particularly when trying to maintain good genetic diversity of your stocks. It's commonly used in selective breeding to FIX a recessive mutation (isolate the recessive genes).

If it's fry crossed to unrelated F0 adults it's considered an "outcross" which does just the opposite of a backcross. It introduces greater genetic diversity in your resulting fry.

[pleco_farmer]

Definitely an outcross, its the reason why we put forth effort, and additional tank space, to track lineage. But is there notation in the F0, F1, etc to designate the F0/F1 offspring? Likewise F1/F2? I'd like to refer to these generations properly. We tend to save the best for breeding, and positively avoid any inbreeding, since we aren't trying create monster freaks, just keeping the lines healthy.

[Barbie]

I've always felt that the filial generation should be related to the parent closest to the wild collection state, but during the discussion of the subject recently at duboisi.com, it's clear most people prefer an offspring of an F0/F1 cross to be called F2. This made absolutely no sense to me, as you're trying to denote how many generations from an outcross of new "blood", for breeding purposes. I would probably just call them fry from an F0/F1 cross, personally ;)

Barbie

[pturley]

Barbie Wrote:

I would probably just call them fry from an F0/F1 cross, personally

Actually, I'd include that they were an "F0/F1 outcross". Clearer indication of their lineage.

[Barbie]

Yeah, what he said ;) I wouldn't intentionally cross fry back on a parent, so I tend to assume people would know that automatically. Paul's method clarifies it much better

Barbie

[Caol_ila]

Hi!

How do you keep track of the fish used for breeding? photo history? I imagine its difficult to say who is who when you have 30+ fish? Just out of curiousity.

[pleco_farmer]

Actually, it takes quite a bit of tank space. I do a great deal of plywood tank work, and have built 100 gal rearing tanks which have been divided into ten gallon sections. Spawns are tracked with dry erase labels directly on the rearing compartment. When my F1s were getting to maturity, I grouped them off, avoiding any inbreeding. Then the breeding compartments are labeled. If you keep your head, you can later even move these guys, or gals, around once or twice, but then it starts getting ridiculous, especially over time, because you start to lose track of which male is which, etc... Presently, if an exceptional F2 appears, usually a big hairy male, or an unusally large female (pick of the litter kind of thing...) we remove those to breeding compartments, but then start to lose lineage, so on and so forth...

Its not like selective breeding for characteristics, again I just try to avoid inbreeding for health reasons. Since you are ruling out a minority of cases, instead of selecting for them, the permutations are numerous enough to keep it easy. So, if you know where three females came from, you just keep them away from spawn of any of their parents. I don't really need to track individuals.

So, F1/F0 outcross it is, sounds nice and technical. Its funny, LFS owners dig F1 for sale, but would rather a F1/F0 than a F2. I'm ready just to dump it all and just call them "tank raised"...

Thanks for all of your input, and Barbie's patience, didn't mean to hijack the thread....

[Barbie]

Well last night two of the zebras were finally sharing a cave, and this morning, I have eggs! I assume this first batch won't be fertile, as the female has held them too long, and that has happened with my L260, in getting them started, but eggs! I've got eggs!

The larger of the two fish I had labelled from the first group of pictures is the one on the eggs. I won't be taking pictures this time, no matter how badly I want to, but hopefully I'll get a repeat performance

Barbie

[INXS]

Congratulations Barbie!!!

Just slightly jealous you certainly deserved the success after all the pains you went through.

Hoping for pictures soon.

[Barbie]

Well it's not a success yet, but at least it's a step in the right direction!

I was very proud of myself. I managed to not run screaming into the bedroom to jump on the bed and wake Bob up, since he didn't get off work til 4:30 am, lol. He said he was amazed I didn't have to find a paper bag to breath into just to make it up the stairs

It's just a comfort to know that they aren't reproductively challenged. Now I get to try not to be patience challenged and not look in there with the flashlight

Barbie

[pturley]

IME (and I am certain I'm not the only one) the first clutch of eggs with any catfish is always the hardest to get. Congratulations...

Keep us posted.

[Barbie]

I'll be lucky not to drive everyone crazy with news, let alone worrying about missing an update, lol! Thanks though, it's very encouraging to see something happen!

Barbie

[Kenneth Wong]

Congrats Barbie,

By any chance do you know which one was the female from the pictures you posted. I am curious as to which is the female and how it looked.

[Barbie]

I don't, actually. I didn't want to disturb them. I intend to go down and see if I can tell when I do water changes on the other tanks this evening. If I can, I'll surely pass it on!

Barbie

[Harri]

Good luck!

I wonder how big is the breeding cave? I have 8 zebra plecos and tomorrow going to go cut "rock" and do few caves.

Sorry bad english.

[Barbie]

The caves are built to the specifications that Larry laid out in his online chat lecture about spawning. Basically just tall enough they can get in, and 1.5 times the height, wide, with 1.5 times their length.

This is the female that looks likes she spawned with him. (Rub marks on her side and a somewhat distended vent).



This is the male who is guarding the eggs.



Hope that helps anyone at all

Barbie

[discusion]

Congratulations Barbie

I have zebras that are about too lay eggs for the 2 time. Now that I`m writing this the female is fighting too get into the cawe

The first was infertile, soo I hope they doo bether now. But I`m wondering if I shuld continue too change wather? I have changed 20-40% water 3-5times a week, and replased it with cold wather. The temp goes from 29 too 26 degres. Shuld I continue too do so now that they hawe egg again?

I have good filtration, so the water quality is not gonna be a problem if I stop doing wather changes. The only problem can be the pH that goes from 6,5 too 6.

Tom-Erik

[Barbie]

I wish I knew? LOL! I continue to do water changes on my L260 tanks when they have eggs with no problem. I didn't realize they had spawned already and put them through an entire rainy season back when they first started and I wasn't allowed to check on them with the flashlight ;). Once I saw they did alright with that, I didn't worry. I would probably stop fluctuating the temp as far as that once they spawn, but I'm not sure there's any valid reason to worry about it.

Barbie

[Barbie]

As of this evening, the eggs are gone. Hopefully he'll have better luck next time My big worry is that we'll have to go through this with each of the females. Hopefully my heart can stand the suspsense LOL!

Barbie

[madattiver]

ohh wow.. u finally got them to spawn.. all that hard work paid off.. well almost paid off.. but i am sure it will only get better now thta they have started.. i am so excited for u.. hope they get at it again soon, and this time figure out how to fertilize and care for the eggs.. maybe u should set up a tv with a video on parenting 101...

[Kenneth Wong]

After looking at Barbies Zebra photos for a second time, I don't know how you can tell males from females except for looking at the vents. It appears that both males and females in her group have Odontode growth on the gills and the Pec. spines. Very confusing. The girth on the males and females look the same and even the Head shape is hard to distinguish. What does everyone think. I sure hope mine aren't this difficult to sex when they are mature.

Does anyone know how long it takes to get a 1 1/2 inch or 2 inch zebra to breed size and maturity. Does it depend on size or age?

[Barbie]

Actually, the males DO have more odontodal growth, IMO, maybe it just doesn't show as well in the picture. It appears I wasn't far off in what I thought the sex ratio was, so behavior will definitely help you sex them. The males used caves, the females usually did not ;)

Barbie

[pleco_farmer]

You really need to see them in three dimensions, live, in both light colored bowls and dark ones. However, even the subtle differences in body shape are readily apparent from Barbie's pictures, which are great examples. From the pectoral fins rearward, males tend to a "V" shape, while females are more eliptical. In these photos however, the males are well fed, which causes them to look plump, more female in appearance. But, if you examine the body area BEHIND the pectorals, from above, you will note that the females look "pinched" before they round out. In some there will be a pronounced flat section on the side before the bulge outward. This is much more noticeable in a female than in a male. And, this is very obvious in 3-D. Flat pictures make it tough. Due to the extra odontal development, some males will have a pinch ahead of the pectorals. Again, this is comparative.

Secondly, the odontal growth that you see in these photos is what is termed a substantial difference. I think it is pronounced for these younger zebras. Note that this does not mean an absence of odontal growth on the females. It is simply more prevalent in the males. This is best seen in a dark bowl, from multiple angles.

Now, let's assume that the distribution of sexes available for retail is equal. It probably isn't, but I have not seen a huge disparity. Given a group of six fish, the odds are 32:1 that they are all the same sex. Given eight fish, they jump to 128:1. So, if you have six fish, you are pretty sure to find at least male and one female. The differences are not huge, but if you view them together, and forget about this broken stripe nonsense, the sexes should emerge.

I don't mean to sound so stern, but I get many requests with poor pictures from individuals who think that a lack of spawn means that they don't have opposite sexes. After talking to them, I find out that they have only had the fish for three months. Relax, raising this species takes time and patience. If I rearrange the rocks in a breeding tank, it can throw the group off for six months. However, once they are situated and comfortable, basic quality aquarium care is just about all that is needed. Just give them time.

As for growth rates, this guy is a slow grower. In six months, fry barely reach an inch, and that is their growth spurt. Our F1's spawned after 2 1/2 years. Is that the period to sexual maturity. Probably not, because there are so many other factors involved. But it is the earliest I have seen them spawn, knowing how old they were from the start.

[boxlotfish]

http://boxlotfish.com/images/zebranewSEX2.jpg
Here is a page I put together for sexing Zebras. Part of it came from the http://zebrapleco.com site and part came from my tank.[/url]