Backyard Aquaponics
A place to discuss aquaponics

Thx for the link Scotty very interesting read. Dies anyone know if skrettings uses the natural form or a synthetic form?

There is no doubt that the orange flesh is far more attractive. If farmed Atlantic Salmon were produced with white flesh it would struggle to sell and compete with all the other white fleshed fish. As it is when you look over the display at a fish mongers the bright orange flesh immediately makes it stand out.

Thanks for your input Troutman.
Thanks for the link too Scotty.
Interesting that it's fed to chooks too for yolk colouring.

Below is text copied and pasted from Skretting Australia Website
http://www.skretting.com.au/Internet/Sk ... 10_web.pdf

I like the bit where they say its more economical earlier in the lifecycle....so why is it in the larger sized pellets???...and the bit that says "Nature Identical Astaxanthin"....

Astaxanthin is a naturally
occuring carotenoid that
wild salmonids extract from
crustaceans they consume.
The pigment is then laid down in
muscle tissue and transported
to eggs during the breeding
cycle of large salmonids. In
aquaculture, nature-identical
astaxanthin is added to feeds to
mimic this natural intake and is
deposited in the flesh to provide
the fillet pigmentation we see on
retail shelves.
Aside from the pigmentation of
salmonid flesh, astaxathin has a
range of functions that influence
many vital morphological and
physiological processes.
There have been suggestions that
astaxanthin should be listed among
the fat-soluble vitamins due to the
discovery of similarities discovered
between astaxanthin, vitamin E and
vitamin A.
Nutritional functions of astaxanthin
include antioxidative capacity,
improvement of egg quality and
embryonic development, increased
growth and survival and better
health and immunity.
GETTING THE MOST OUT OF
ASTAXANTHIN
You may have noticed the
differences in the ‘intensity’ of
pigmentation in different salmonid
species. This is related to the ability
for different species to retain pigment
from the feed. For example, both
rainbow trout and chinook salmon
typically are more pigmented than
their Atlantic salmon cousins, as
these former species generally
retain astaxanthin at around
20% compared to only 10% for
Atlantic salmon.
Our understanding of how
astaxanthin should best be
supplied to salmonids has
also changed. In years gone
by, typically higher doses of
astaxanthin were used towards
the end of production to colour
the fish prior to harvest. We now
know this is the least efficient
method (and most expensive), and
now it is common for astaxanthin
to be used in higher doses early in
the lifecycle with the concentration
gradually reduced. This least-cost
pigmentation strategy still results in
beautifully presentable fish.■
Australasian Aquaculture 2010
If you haven’t got your registrations in yet, it’s not too late!
The theme of this year’s conference is “Keeping Pace With
Change” whether that be economical, technological or
environmental change.
Skretting will again have a strong presence at the conference,
and we will be launching our new salmonid hatchery range,
including Nutra XP and Spirit Supreme. Roar Sandvik,
Product Manager fro m Skretting Norway will be making the
journey to Hobart to introduce the feeds and be on hand for
any technical questions.
Please contact us if you need any further information.
23-26 May, 2010
8 • Skretting Nexus Autumn 2010
Raw Material Focus
Astaxanthin
Nutritional functions of
astaxanthin in fish
Antioxidant
Egg quality and embryonic development
Growth and survival
Health and immunity
Vitamin A precursor
Snippets

Lol Matthew maybe because its "the least efficient
method (and most expensive)"?

Ps thanks for the info I guess we make our own judgements on whether it not we think its a good thing. Personally I would prefer the natural shellfish in the pellets and with the price we pay for them I would expect it. But I guess they're made for the industry.