Traditional farming has been the only method
available, using existing or cultivated dams and allowing the
yabbies develop at their own pace. This is a hap-hazard
affair.
ABYA™ has now developed the Extreme Density Unit
(EDU) system of farming, a totally
controlled growth environment producing a consistent, market-ready product in a quicker time frame.
The EDU is provided as a
ready-to-run kit, supplied complete with everything you need,
including the initial yabby stock.
WHAT IS IT?
A brief Overview of the EDU™ system and the ABYA™
technique to cultivate yabbies.
An indoor recirculation system that houses yabbies in a three
dimensional grid allowing for maximum density grow-out.
Employing this method of production, over 1000 yabbies can be
cultivated in only one square metre of floor space (for yabbies
weighing 50 grams). The yabbies are housed throughout their
growing period within ‘Strata Cells’.
The EDU is a true ‘Dual Specie Grow-out System’. Various
species of Cherax have shown acceptance to the strata cell
environment as well as various species of fish (eg. Bettas,
otherwise known as Siamese fighting fish). Free swimming fish
also serve a valuable function within the EDU system, they aid
in water movement and as a perceived aggressor to the yabbies,
thereby ensuring the yabbies are well exercised and therefore
hungry. Various sizes are available for industrial or
backyard/hobby growing. Attachments such as vermiculture and
horticulture also aid in water quality, heating and removal of
nitrates.
GROW-OUT DENSITY COMPARISON
Comparison of three farming techniques, yabbies harvested
from 1 m3 of water per season.
| Traditional
(dam) |
Semi-intensive |
EDU™ |
10 small
5 large |
25 small
15 large |
1008 small
281 large |
It can be seen from the figures above that the output from an
EDU system far exceeds traditional methods (dam & intensive).
Up to a 10,000% difference for EDU farming
over traditional dam based farming can be achieved!
Traditional farming requires a lot of land to build and
maintain adequate dams, it needs to be of the right soil type to
hold the water volumes required and has to be within the right
areas to assist in distribution of the final product. Yabbies
are hardy creatures; they proliferate in what we would consider
murky conditions and are generally good, self maintaining
breeders. They can however, be affected by stress. Combined
problems of overcrowding, limited feed and bad habitats can
cause stress levels to be at a point where they die. High
mortality rates of up 95% are considered acceptable in
traditional farming techniques and for those that do make it,
harvesting often damages the yield, breaking claws or legs which
make them undesirable for market.
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Pic 1. Strata post with 18
Strata Cells attached |
Pic 2. Strata posts hanging in EDU system |
WHAT IS THE YIELD PER M 2?
(Based on industrial
size tanks that are 1.5m deep)
1) Yabbies?
-
75Kg with yabbies weighing 50 grams each
(1,516 yabbies per m2)
-
80Kg with yabbies weighing 200 grams
each
(412 yabbies per m2)
2) Fish?
CARRYING CAPACITY OF THE
EDU SYSTEM PER M 3
Fish are not considered in m3 volume calculations.
50 grams = 50.4Kg per m 3
or 1,008 yabbies
200 grams = 56.2Kg per m3
or 281 yabbies
The EDU takes yabby farming indoors. This allows total
control over the weather conditions, lighting, water quality and
even security during the full development of the product.
Productions of high densities are possible because this
technique provides for a 3D dimensional population.
 |
 |
Pic.3 EDU™
3D strata cells
(20gm Cherax destructors) |
Pic.4 Start and finish sizes
for
small strata cells (6 to 50+grams) |
The Extreme Density Unit (EDUTM)
was developed to resolve problems that traditional farming
techniques encounter for example, from predators (nearly every
living thing around them at some stage in their life cycle),
drought, theft, seasonal variations and natural tendencies to
wander just to name a few.
Water temperature is maintained at an
optimum level and lighting simulating the seasonal condition to
accelerate their growth cycles can be monitored. These variables
can be adjusted to provide the best possible conditions for
breeding and growth.
Water quality is important. Dirty water in
dams is normally an advantage to the yabby; if they can't see
each other then they are less likely to fight and damage
themselves. At the time of harvest however, these yabbies must
be cleaned and purged to make them suitable for the market. The
EDU uses a technique to separate each individual yabby so this
damage does not occur. Clean, clear water can be used during the
growth cycle. Cleaning and purging is no longer an issue during
the growth process because the contents of the Strata Cell can
be easily inspected and sized without any difficulty.
Feeding is a controlled procedure. At
regular intervals, a high growth feed is provided to promote
it's full growth potential. This is increased over the lifespan
of the yabby as it grows and requires larger amounts of food.
Farmers calculations are based upon a 2% feed ratio over total
bio-mass of the EDU tank.
Eg. 2% of 100Kg of yabbies in tank = 2Kg feed to
be dissolved in feeder.
Harvesting is quick and cost effective.
Traditional methods require netting/trapping the stock in the
dams, returning the various sizes and qualities of available
stock for later sorting, purging, sale or discarding. As yabbies
are kept in individual cells in the EDU, removal of each high
quality, pre-purged and sorted unit is quick, easy and
efficient.
Large dams in distant paddocks covering hectares
of space are prone to pilfering. Aside from birds, eels and fish
that can easily enter a dam, it's not uncommon for looters to
net a dam and head off. By being fully indoors, the EDU is as
secure as the locks and alarms in the building.

Culture or purge?
The EDU can be used not only as a ‘Aquaculture
unit’ for yabbies, but also as a ‘Purging unit’. The difference
between the two is that the /A - Aquaculture unit, is used to
CULTIVATE or grow-out yabbies from juvenile size, as opposed to
the /P - Purging unit which is used to CLEAN pre-existing dirty
dam stock.
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