Feed enrichment via microencapsulated diets

[FuEl]

As usual, too early for me to sleep. Had an interesting practical on enriching artemia and rotifers using microencapsulated diets. This should be more efficient than just feeding them with Selco as after all oil floats. Should be able to improve survival rates of marine larvae.

Materials you need

- 2% gelatin solution

- 2% acacia solution

- enrichment formulations like Selco, cod liver oil, squid oil, maybe some spirulina power (I will explain my choice on this later)

Basically the solutions need to be kept at 40 degrees celcius before mixing if not they might harden upon cooling down. An equal volume of gelation solution is mixed with an equal volume of acacia solution.

This mixture is then put into a food blender. Enrichment solutions are dumped in too. The mixture is blended for 1 min at maximum speed.

The mixture is poured into a beaker and stirred either manually or using a magnetic stirrer. This prevents the oil from the enrichment solutions from floating to the surface.

Add dilute HCl drop-wise to this solution slowly till pH reaches 3.9. Gelatin then becomes positively charged and it will be attracted to negatively charged acacia. Such attraction can only occur around foreign particles.

leave the mixtures stirring while performing pH changes. After pH reaches 3.9 let it mix for 2-3 minutes before adjusting the pH up to 9.3.

Dilute NaOH is then added drop-wise till pH goes up to 9.3. This removes excess gelatin-acacia coating around the microcapsule. Without this step, microcapsules might be too large with excess gelatin-acacia coating.

The mixture is then diluted 50% to prevent the mixture from hardening too much and it is then cooled in the fridge for 10 mins.

Examine under a microscope to see if you have successfully encapsulated your enrichment formulations. If your enrichment formulation is hard to see due to transparency, it might be good to do a test run with a lipid dye added. If it is done successfully, this solution can then be used to enrich rotifers or artemia.

As mentioned above..I suggested spirulina as it is high in protein. Other enrichment diets are composed mostly of lipids and hardly protein, if any. Enrichment of artemia using such enrichment diets alone like DHA Selco will lead to increase in DHA content of artemia over time. However, protein content of artemia will decline. If spirulina can't be encapsulated, a good alternative would be to feed the microencapsulated lipids, together with ultrafine spirulina powder to live feeds. Golden pearls might work too, as I have seen them to be rather high in protein content.

Main thing is to enrich live feeds with both lipids and proteins. This might give better survival rates compared to just enriching artemia or rotifers in oil solutions which might not be that efficient.

Haha feeling sleepy..hope some guys try this out! *looks at Chinmo..for your Reidi fries!* *looks at marinebetta..for your percula fries!*

[chinmo]

Good Info! will try to try it out.

[bawater]

Ah forgot to add..leave the mixtures stirring while performing pH changes. After pH reaches 3.9 let it mix for 2-3 minutes before adjusting the pH up to 9.3.

Good if a mod could help me get this info into my first posting.

Done.

[FuEl]

Done.

Most helpful of you..have'nt met you before. Would be my pleasure to meet up with you when I return to Sg.

[FuEl]

Heh..stumbled upon an article on the benefits of this compared to other enrichment diets for Artemia. Did'nt know my lecturer was involved.

microencapsulatedHUFA.pdf