Catfish talk i wanna hear you guys thoughts on this
- Thread starter Paradox2296
- Start date
True but you gotta admit that it's a big kitty when 40-50 lbs. is insignificant!
Honestly there is a much bigger difference in size between a tiger and a lion then only 40-50lbs, according to Wikipedia a male lion on average can weigh anywhere from 4-500lbs while a male tiger can weigh anywhere from 400- "almost" 700lbs on average. When it comes to the females however they tend to be pretty even when it come to weight, female lions can weigh roughly 2.5-300lbs while a female tiger can weigh from 2.8-320lbs, so not much of a weight difference between the females of the specie.
Regardless tho on the specifics we should let the OP take this thread back over so we quit flooding his thread with unrelated info on an unrelated topic.
Good debate in this thread. It sounds like fisherman Dave is most like referring to a paper I remember reading maybe 12-15 years ago haha. I do remember presenting some interesting research I found on here back then about hybrids produced in SA farms. I even spoke to a farm back then.
I will not try to qoute from memory. If and when I have time I will try to dig through my old posts and see if I can find it. Maybe do some modern research. The papers did list hybrids that were produced on farms. Some were utilized more than others once the carcass yields were calculated. Keep in mind these farms are looking for growth rates and carcass yields. They care not about the looks of the animals. That's apparent when you look at any fish farming operation. The hatchery trout I catch here in Montana range from looking almost natural to some so deformed I'm not sure how they even survive with almost no fins and gill coverings.
As far as head deformities on hybrids we did a long time ago also cover that pimelodidae in general seem to all get this at some point with Pseudoplatystoma seeming to have the highest number of instances in our hobby. Thus my indirect observation would be that most likely these farms are producing both the parent species and hybrids. So if you are artificially breeding a deformed Pseudoplatystom with a dominant or codominant trait for this it will likely at some percentage be passed on to the offspring be it hybrid or not. This can bee seen in snake hybrids as well. Since they do not cull these and breed them back in you will get a higher and higher percentage over time. They only care that they are reproductively viable and provide a good carcass yields as well as growth rate.
As for the pattern it has been my observation as well that they tend to darken up when at a larger size also. I do also agree that tail shape and head shape and body proportions are not an ideal way to determine which is the parent species. Especially as this is not a naturally occurring hybrid. They also are probably not always using the same species of Pseudoplatystoma to produce these hybrids no matter how hard they try.
I do not remember reading up on interbreeding of hybrids in those farms to produce F2 or later hybrids. I'm uncertain if the F1 maintains any fertility. If they do breed F2s or later that would be interesting. You could possibly get a different looking animal for sure at that point.
I think the main thing I take away is that they are not using anatomically typical parents always to produce these hybrids and they will have a high degree of variability even when produced with female Pseudoplatystom to male Phractocephalus. Look at the amount of variation just within the parent species. Not all of these fish come from the same two parents. Add in the higher than normal hybridization within Pseudoplatystoma. I suspect that before Pseudoplatystoma was revised many of these farms were making Pseudoplatystoma sp. x Pseudoplatystoma sp. Hybrids as well and probably are still to this day using brood stock from those hybrids.
Unfortunately I was never able to deliver DNA samples to Dr. John Lundberg. He was to do DNA analysis of my hybrids many years ago. This would have been very interesting but life was a bit hard on me and I've had to prioritize other things. He was very fascinated to see what the raw data said.
I hope this wasn't too much rambling. I'm not sure when I will have time but I will at some point dig through some old data and see what I can find again. If anyone has found newer research I'd be interested to look at it also. I use to have lots of papers on hybrid catfish in both North America and South America. It was interesting to see all the species used and which was the parent species.
I will not try to qoute from memory. If and when I have time I will try to dig through my old posts and see if I can find it. Maybe do some modern research. The papers did list hybrids that were produced on farms. Some were utilized more than others once the carcass yields were calculated. Keep in mind these farms are looking for growth rates and carcass yields. They care not about the looks of the animals. That's apparent when you look at any fish farming operation. The hatchery trout I catch here in Montana range from looking almost natural to some so deformed I'm not sure how they even survive with almost no fins and gill coverings.
As far as head deformities on hybrids we did a long time ago also cover that pimelodidae in general seem to all get this at some point with Pseudoplatystoma seeming to have the highest number of instances in our hobby. Thus my indirect observation would be that most likely these farms are producing both the parent species and hybrids. So if you are artificially breeding a deformed Pseudoplatystom with a dominant or codominant trait for this it will likely at some percentage be passed on to the offspring be it hybrid or not. This can bee seen in snake hybrids as well. Since they do not cull these and breed them back in you will get a higher and higher percentage over time. They only care that they are reproductively viable and provide a good carcass yields as well as growth rate.
As for the pattern it has been my observation as well that they tend to darken up when at a larger size also. I do also agree that tail shape and head shape and body proportions are not an ideal way to determine which is the parent species. Especially as this is not a naturally occurring hybrid. They also are probably not always using the same species of Pseudoplatystoma to produce these hybrids no matter how hard they try.
I do not remember reading up on interbreeding of hybrids in those farms to produce F2 or later hybrids. I'm uncertain if the F1 maintains any fertility. If they do breed F2s or later that would be interesting. You could possibly get a different looking animal for sure at that point.
I think the main thing I take away is that they are not using anatomically typical parents always to produce these hybrids and they will have a high degree of variability even when produced with female Pseudoplatystom to male Phractocephalus. Look at the amount of variation just within the parent species. Not all of these fish come from the same two parents. Add in the higher than normal hybridization within Pseudoplatystoma. I suspect that before Pseudoplatystoma was revised many of these farms were making Pseudoplatystoma sp. x Pseudoplatystoma sp. Hybrids as well and probably are still to this day using brood stock from those hybrids.
Unfortunately I was never able to deliver DNA samples to Dr. John Lundberg. He was to do DNA analysis of my hybrids many years ago. This would have been very interesting but life was a bit hard on me and I've had to prioritize other things. He was very fascinated to see what the raw data said.
I hope this wasn't too much rambling. I'm not sure when I will have time but I will at some point dig through some old data and see what I can find again. If anyone has found newer research I'd be interested to look at it also. I use to have lots of papers on hybrid catfish in both North America and South America. It was interesting to see all the species used and which was the parent species.
That's very interesting thanks for the info if you do find that information is kove to see it I personally love the TSN×RTC hybris especially my largest one probably my favorite catfish behind a red tail but hey if any of you guys still have your hybrids post pics id love to see them
I wish I still had mine. Look forward to seeing others also. Thebiggerthebetter has a ton of videos with his big hybrids as well as a ton of other catfish. All amazing.
FWIW our thread: https://www.monsterfishkeepers.com/...ids-at-fish-story-aquarium-and-rescue.699928/
and some photos - here is 3' one with the camel face / duckbill deformity:
The snout on this 30" one was better but still not straight:
and some photos - here is 3' one with the camel face / duckbill deformity:
The snout on this 30" one was better but still not straight:
