ABMac

This diet is still under research & development and its application as (possibly) a general growout diet is still not decided, being solely dependent on final production costs and the FCR (feed conversion ratio) factor achieved as either a supplemental or 100% substitution diet.

Preliminary trials by three production abalone farms along the coast of California indicate that the animals accept and feed on this diet once they have been acclimated to its physical properties. As recognized, abalone normally fed on kelp may take some time to adjust to this new format and early feedings may be minimal. The type of culture systems incorporated is also very important. The diet, in its current format, is designed as a sinking sheet. Aquafauna Bio-Marine (ABM) is currently working on a floating format based on the same formulation.

Preparation: ABMac is supplied as a dry powder mix. It needs heat to activate along with 10 parts freshwater to each part of dry mix (for example: 500 ml freshwater to 50 grams dry mix). The procedures for preparation are quite simple. The required equipment which the customer must have are: a) A heating source like a stove or hot plate; b) A thermometer; c) Flat pouring and setting surface like a cookie sheet; and d) Mechanical stirring device.

We have found that hand stirring works, but if you apply too large an amount of the dry mix to the pre-heated water (60-65 degrees C. [about 150 degrees F.]), you will form clumps which are harder to break or disperse by hand mixing action as the solution becomes thicker. This is why we have also used a mechanical stirrer (or hand cake mixer) with adjustable speed control. Slow, mechanical stirring is best, with just enough to disperse the dry mix as you are mixing it into the preheated water. Setting the mechanical mixing at high speed will infuse air into the mixture and this weakens the sheet material upon setting (the sheet will remain highly stable, but will come apart into smaller pieces more easily).

It is recommended that the preheated freshwater be kept under 70 degrees C. to minimize the loss of nutritional elements and fatty acids. The dry mix should be blended into the preheated water thoroughly. Once this is done (a few minutes at most, but never let boil or exceeding 70 degrees C.), pour the mixture onto a cookie sheet to a depth of about 3-4 mm thick. The mixture will set within two minutes and may be separated from the cookie sheet under running water after it is scored into convenient sized strips. Some farms suggest that this sheet should be cut into "squares or circles" with a cookie cutter. This philosophy is based upon theory that more pieces in the tank allows the animals to feed over a wider area rather than all animals competing for long strips of diet.

If the mixture is disturbed before it has cooled off, it will fracture easily. However, if after the cookie sheet has cooled (a couple of minutes or so), the sheet material may be separated from the cookie sheet under running water, especially if it has been scored into strips. These strips, when introduced into seawater, will become tougher and more elastic over the next 5-6 hours since there is a calcium exchange occurring. This exchange, in fact, contributes to the high state of stability the diet will display over the next 4-6 days in seawater.

This diet may also be dried out from sheet form (sun drying is accomplished within half a day). It should be noted that dried diet, when re-introduced in seawater, will not re-hydrate to its original form. It will however, form a sheet material which is tougher and more leathery than freshly made product.