Bent Jaws

[FullyYellow]

Hey guys,

I was just wondering if fish with bent jaws will pass it on genetically and should not be used for breeding. Would like to see a discussion on this

[Buccal]

Yes Definetely mate, if the bent jaw is a deformity and not a injury,, then yes, deformed offspring will occur.

If for a small possibility, the offspring turn out not deformed,,,, then the deformity will for sure show down the line of future offsprings coming from the following bloodline colonies.

[andy123]

i would like to appreciate you for sharing such a great info with us

[Noddy65]

Hmmm...there is not necessarily an easy answer (is there ever?)...this deformity MAY be heriditary but there is also a link ( a very strong link) between diet and deformity in fry....so....its not an easy question....Would I breed from deformed fish...NO...cull them...would I still breed from the parents?...probably...but Id change the fry raising diet next time and see the results

Mike

[Noddy65]

Some possible theories (moslty to do wth trout but some could apply to aquarium fish)

On the contrary most authors believe that poor rearing conditions are a likely cause, in particular in relation to:

• nutritional deficiencies in the broodstock during ovogenesis (the most probable);
• inadequate lighting during incubation;
• excessive egg density (leading to mechanical stress and limited oxygen supply);
• handling, salinity or thermal shocks;
• pollutants in the rearing environment;
• a mix of the above mentioned causes.

Some nutritional deficiency seems the more realistic hypothesis because rearing techniques (feeding sequences, preys, artificial feed, etc.) are more or less the same in most hatcheries. Looking at nutrition more in detail, a deficiency in vitamin C and/or a toxic excess of vitamin D could represent the most probable candidates. Vitamin C is one of the main agents in the collagen metabolism, an essential component of the bone tissue. Vitamin C deficiency can easily be explained by its high solubility in water.

The hypothesis of hypervitaminosis D is also attractive because it takes into account the appearance of urinary calculosis. This vitamin is present in large amounts in the fish oil used to enrich rotifers and brine shrimps for larval fish, as well as in the fish viscera, a component of artificial feeds used in the nursery stage. Tuna liver oil, for example, may contain up to 200 000 IU of vitamin D and cod liver oil up to 500 IU per gram (1 International Unit = 0.025 µg of vitamin D2 as crystalline form).

[E4G13M4N]

Good info there Mike.

Like the elliotti's most deformity in those, most people seem to think it is diet / vitamin related as baby's

[FullyYellow]

Thanks Michael I've separated the male into my bigger setup away from all females.

[Buccal]

Yes, deficiency during growth development is another,,, but I think that effects the next generation offspring also ( fry coming from parents effected by growing deficiencies ), so segregation is same outcome as for a genetic deformity.

But from what I've researched it seems to be Americans more effected by deficiency.

Most times with Malawi deformities I'm thinking it's more genetical.

As for the Ellioti, I've spoken to experienced people about this that seem to think its a deficiency in water quality.

I'm am breeding these working extensively with offspring after offspring pairs trying to rid the deformity.

I'm Definetely reducing the deformity percentage in offspring through continual selection, it's really working.

So this shows me its genetical.

Also interesting,,,, as time goes on, they seem to be breeding now at much smaller sizes.

Less deformity percentage seems to be in males.

I'm down to about 30% offspring deformity.

When I started it was 80% percent deformity.

[FullyYellow]

Wow that is really good Buccal hopefully your sending your fry all over Aus to keep the genetics.

[Buccal]

Yes it is all over oz, but a lot more work is still needed.

I have sent a few over east.

I think every one else has given up on them.

It's likely when people see a few not quite right ones out of a biggish batch they won't want them.

But it's all we have and they are worth working on, and I hope others do some selective breeding with them also.

The deformity does seem more prevalent in the female gene.

If with any fish, there is a deformity in that bloodline,,, and other bloodlines exist with no deformity,,,, then all deformed bloodlines must be cullled to safeguard the correct genetics.

But seeming Ellioti don't really easily make it into oz,, the ones that are here should not be let go off,,,,,,,,(just yet).