Using Wild Angelfish to Improve a Line

Author: Dave Hlasnick

I would like to describe a few of the many breeding projects that we are currently working on. A little history will be necessary due to the fact that making changes to the genotype and phenotype of animals obviously takes time. My focus is and always has been, working to improve the Koi angelfish.  Although Steve and I have collaborated on breeding projects a number of times over the years, a few years ago we made the decision to combine our facilities. It was obvious to both of us that it would be far easier to accomplish many of our goals if we worked together. This would allow us to keep a number of different lines for each variety. It would also give us many more varieties to choose for outcrosses. Once the decision was made to combine stock, we sat down and made a list of projects that would be interesting and fun. We knew that these might take “a while” to accomplish but that is part of the enjoyment, I suppose.

In any case, these are some of the breeding goals that we decided upon (I am only including the Koi angelfish projects. Other angelfish, livebearers, bristlenose, etc will be discussed in other blog entries):
  • Albino Koi Pearlscale
  • Koi – Extended fin color (ventrals, caudal, dorsal and anal fins)
  • Platinum Koi – We are into the third generation. The jury is still out on whether we will continue with these. We are still watching for a unique specimen or a trait that catches our eye.
  • Orange marble – Not exactly a Koi project,  but a very similar fish where our goals are to increase the intensity of color, not necessarily the percentage of coverage.
  • Red-back Wild-type – By crossing Koi to Peruvian Wilds, we are attempting to produce our own version of a Manacapuru – only better.
  • Wild-cross Koi – Outcross to 100% Wild Peruvian. This has proven very beneficial in keeping this very inbred strain, strong, vigorous, prolific and extremely beautiful.   This is the process that I will be describing in this blog.
Two years ago Steve and I went through the Main Hatchery and selected the two best looking Peruvian males. We selected one massive male which had all of the characteristics that we were looking for, and one slightly smaller fish which had very good color and shape. The 100% wild fish are normally very difficult to sex but we make our best guess based on size, and the really big ones are usually males. These were really, really big ones. I have added a picture of the largest male which doesn’t do the fish justice. He absolutely dwarfs the average size of the females we put with him. His body is nearly 5″ in length, not counting the tail.
 wild peruvian koi angelfish male
Having had the experience of doing this type of cross in the past, I expected these males to take some time to acclimate to the Koi we decided to put with them.  100%-wild angels tend to stay to themselves when placed with other angelfish.   In order to combat this, each wild male was placed in a separate 20-gallon tank with only Koi angelfish as tank mates. The best-case scenario would be for each male to select a Koi female as a mate. That didn’t happen right away but I’m convinced that the time spent with only Koi tank mates eventually made it easier to coax the male to accept a Koi female later on. It has worked this way for us many times in the past when making such wild crosses. Finally, I gave the larger male a large tank to itself. I kept two Koi veil females with him until he finally spawned with the more aggressive female. He ate most of the eggs in the first spawn but left enough to allow me to hatch a few and at least confirm that he was a male. I kept very close track of the pair after the first spawn.   When a rainstorm was predicted and the barometric pressure was due to change, I made sure to feed the pair so much that the male would be less likely to eat the eggs. It was eventually possible to save a few large spawns.   I like to save a large number of fry when I intend to select future breeding stock. The process of getting this male to spawn took almost a year. Fortunately, our experience is that these wild males are good spawners for 8-10 years, so there was no huge hurry.
Like typical wild-crosses given plenty of space and water changes, the F1 fry were vigorous and fast-growing.   As they grew I selected 20 that caught my eye. Each of these fish was placed into its own 20-gallon tank containing several Koi angelfish for grow-out companions. Two weeks ago I took my best guess at selecting two males and 2 females from this group of F1 Koi/Wild.   Although these fish are only 50% wild, they are still very wild-like and more difficult to sex than domestic strains.  Size can be an indicator but I generally look at the abdomen.   When heavily fed, the females seem to have a little more elasticity in the abdomen which allows a slightly larger, rounder look. These two males and two females were paired with colorful Koi from HR breeding stock. 
F1 Koi x wild angelfish 
So far, I have two spawns swimming.  One spawn from a 50% wild F1 female x solid orange Koi male. The other spawn is from a 50% wild F1 male x solid orange Koi female.  In the past, I have always selected my best Koi females for any out-cross. However, in this case I will save both spawns just to observe any differences.
I doubt that anyone can prove the importance of the mitochondrial DNA in a breeding program but it is scientifically proven that the female carries slightly more genetic material than the male. The linear chromosomes in the nucleus are equally donated by the male and female of the pair but the circular chromosomes in the mitochondria are donated only by the female. I didn’t really give this much thought 35-40 years ago when I started my selection processes. I arrived at my decision to follow this pattern through careful observation of the development of many grow-outs.  My best offspring always seemed to come from my best females, and science has now backed this up to some degree. Never forget, one of the best tools of the fish farmer is observation!  I hope to update the progress of this project as developments warrant.
Feedback and comments are encouraged.