Beta Glucan Enrichment

[mesocosm]

Greetings All !

The "research wheel" sometimes grinds slowly, but the results are oftentimes worth paying attention to. While beta glucan has been used by a lot of folks for a relatively long time, there has been precious little peer-reviewed literature regarding its effects on aquatic vertebrates. As someone seriously interested in the dietary enrichment of marine ornamentals, I thought this was worth passing on ...

Journal of Fish Diseases
Volume 29 Page 95 - February 2006
doi:10.1111/j.1365-2761.2006.00691.x
Volume 29 Issue 2


Dietary β-1,3 glucan potentiates innate immunity and disease resistance of Asian catfish, Clarias batrachus (L.)
J Kumari and P K Sahoo

This study investigated the effects of short and prolonged administration of a yeast β-glucan on non-specific immune parameters, growth rate and the disease resistance of Asian catfish, Clarias batrachus. Fish fed with a basal diet (control) and test diet (basal diet supplemented with 0.1% glucan) for 1, 2 and 3 weeks were assayed for superoxide production, serum myeloperoxidase (MPO) content, natural haemagglutinin level, complement and lysozyme activities. Fish were weighed at weekly intervals and specific growth rate (SGR, % increase in body weight per day) was determined. After each week, fish were challenged with Aeromonas hydrophila to measure the level of protection. Results showed that glucan administration at 0.1% in feed, significantly (P < 0.05) enhanced MPO and lysozyme levels, superoxide production, haemagglutination titre and level of protection against A. hydrophila challenge, irrespective of length of exposure. The alternative complement activity and SGR were not affected by the dietary supplementation of yeast glucan. As glucan feeding at 0.1% for 1 week is able to enhance the non-specific immunity and disease resistance of catfish efficiently, short-term feeding might be used in farmed catfish diets to enhance disease resistance.

Source Link (Blackwell-Synergy)

True, they're talking about Asian catfish, but the results are intriguing none the less. JMO.


FYI

[OUinLA]

Thanks Gary. I guess it's possible that something like this could really benefit the captive breeding movement in marine fish. Would it benefit inverts as well? (thinking about the shrimp that are hard to get past settlement).

What form is this in? Where could one attain it? Could "first foods" be enriched with this so that the larvae might have better success rates?

[mesocosm]

Greetings All !

... I guess it's possible that something like this could really benefit the captive breeding movement in marine fish. Would it benefit inverts as well? (thinking about the shrimp that are hard to get past settlement). ...

There's little question that research like this will eventually find application in the marine ornamental industry. Indeed, it seems to me that there are a bunch of seahorse breeders who have been demonstrating the potential usefulness of beta glucan for quite some time now. Also, the use of immunostimulants in shrimp aquaculture has a long history.

Man ... getting pelagic zoea to settle is a major hurdle which has yet to be consistently overcome. There are at least two significant issues: (1) Captive replication of a pelagic water column; and (2) Captive replication of appropriate zooplankton in an artificial water column. Ever tried maintaining and propagating "wild" collected zooplankton populations? We're talking phytoplankton, diatoms, copepod larvae, and "mixed" zooplankton larvae. It is a challenge, to say the least. I tried to do it in my biology classrooms for 3 years and was never successful. I have no idea how one would go about "gut-loading" beta glucan into either zooplankton or copepod larvae, so I have no comment in this regard.

What form is this in? Where could one attain it? Could "first foods" be enriched with this so that the larvae might have better success rates?

Beta glucan is typically available in powder, capsule, and tablet forms. In terms of "first foods" ...

Beta glucan has applications for spawning and rearing fish. Immersing free-floating larvae (embryos) and juveniles of marine fish with beta glucan will make them more resistant to infection and improve growth rates.

Extracted from:
Beta Glucan as a Biological Defense Modulator
By Terry D. Bartelme.
Article Link

* This is a "reprint" of the original article which appeared in Advanced Aquarist (Volume 2, Issue 9, September 2003). Advanced Aquarist Archives Index.

This article also presents some source links, although a few are broken. Type in "beta glucan" as keywords in a Google search and you'll get thousands of hits ... beta glucan is a much-hyped dietary supplement for bipodal humanoids. Just watch out for the binding ingredients.

Having said that, any filter-feeding prey item, like brine shrimp, should be able to ingest beta glucan quite nicely. Although oral administration, either directly for larger marine vertebrates or mixied in with a frozen food, is the most common form of delivery.




Beta glucan has also been discussed in terms of transporting and acclimating fish ...

Adding a biological immune defense modulator such as Beta 1, 3D glucan to the diet will help increase resistance to disease and stress. An overall enhancement of immune response can be achieved by the use of Beta 1, 3D glucan. It has proven in numerous scientific studies to be an immodulating agent that can enhance the major host defense mechanisms of the immune system (Bartelme, 2003c).

Pretreatment with Beta glucan means that the host can activate and proliferate defense mechanisms at a faster rate than invading organisms, giving the fish and their immune system a head start. Beta glucan can be administered in food prior to starving the fish in preparation for shipping. Safety evaluations indicate that Beta glucan is safe over a wide dose range, but a dose of 0.02% a day of body weight is recommended.

Beta glucan can be administered orally to fish by farmers, exporters, importers, retailers and hobbyists alike. It can be administered by exporters 24-48 hours prior to packaging. Importers and retailers can add Beta glucan to the food while the fish are in their care. Hobbyists can add Beta glucan to the food during the initial quarantine period before the fish are moved to their final destination.

Extracted from:
Reducing Losses Associatied with Transport and Handling of Marine Teleost fish. By Tery D. Bartleme. Advanced Aquarist, Volume 3, Issue 5, May 2004). Advanced Aquarist Archives Index.

As a side note, Kelly Jedlicki (Puffer Queen) has a "Beta Glucan" thread going on at MD (LINK) ... be prepared to wait as MD is in serious need of a better server.

As another side note, immunostimulants have been considered as a possible treatment for RTN (The Immune Response of Corals. Part 2: Models for "RTN". By Eric Borneman and Jonathan Lowrie. April, 1998. RDO Article.)



JMO ... HTH

[mesocosm]

Greetings All !


BTW ... the Reducing Losses Associatied with Transport and Handling of Marine Teleost Fish article received some ... how shall I say? ... "entertaining" feedback in RDO's "The industry Behind the Hobby" forum (LINK).


FYI

[OUinLA]

I'm wondering how one might get the typical fry to ingest this. So many of the larvae require require Brachionus plicatilis as a first food and only get to artemia after they reach a certain size. Do you think the rotifers could consume this, even if by accident in a Nanochloropsis tank (green water)? A single rotifer will consume over 100,000 cells of 'nano" in a given day. Surely some of the beta glucan will make it into their little mouths Do you think this "powder" would be too large for them? Would it dissolve and possibly be used by the 'nano' where the rotifers would benefit from it? I doubt the phyto would use something like this though, hmmmmm.

Rotifers are lacking so much, but it's the best "we've" got. It would be great if there was something (like this) to enrich the rots for the smaller fish that can't ingest artemia right away.

BTW, would the artemia be able to take this in or only as adults?

[mesocosm]

Greetings All !

... Rotifers are lacking so much, but it's the best "we've" got. It would be great if there was something (like this) to enrich the rots for the smaller fish that can't ingest artemia right away. ...

Enriching rotifers? ... no worries


Here are a few options to consider ...

The enrichment and retention of ascorbic acid in rotifers fed microalgal diets
M. R. Brown, S. Skabo & B. Wilkinson

The enrichment and retention of ascorbic acid (AA) was investigated in rotifers Brachionus plicatilis fed on microalgae (Nannochloropsis oculata and Isochrysis sp. (T.ISO)) and baker's yeast Saccharomyces cerevisiae. The concentrations of AA of the rotifer diets used in the study differed significantly: 4200 μg g1 of dry weight in Isochrysis sp. (T.ISO), 2600 μg g1 in N. oculata and only 77 μg g1 in S. cerevisiae. Rotifers contained 620 μg AA g1 prior to the experimental feeding. When subsequently fed for 3 h on microalgae at a ration of 0.13 mg dry microalgae per 106 rotifers rapidly and efficiently increased their content of AA: Isochrysis sp.-fed rotifers contained 1600 μg AA g1 and N. oculata-fed rotifers contained 1100 μg AA g1. Concentrations were boosted by a further feeding of a second ration of algae at three times the initial feeding ration; 21 h later, Isochrysis sp.-fed rotifers contained 2500 μg AA g1 and N. oculata-fed rotifers contained 1700 μg AA g1. This represented a 180% and 310% increase in the pre-feeding vitamin concentrations in Isochrysis sp. and N. oculata-fed rotifers, respectively. There were no significant changes in AA concentration in rotifers fed a similar ration of yeast throughout the feeding period (520-620 μg AA g1). Rotifers retained AA during a subsequent 24 h non-feeding period, with no significant changes in the concentrations in any of the rotifer groups. The production of rotifers rich in AA may be particularly valuable for the culture of fish larvae that have a high requirement for the vitamin.

Extracted from:
Aquaculture Nutrition
Volume 4 Page 151 - September 1998
doi:10.1046/j.1365-2095.1998.00060.x
Volume 4 Issue 3

Abstract Source
http://www.blackwell-synergy.com/doi...2rotifer%22%29

Effect of enriched live feeds on survival and growth rates in larval Korean rockfish
Sebastes schlegeli Hilgendorf
S H Cho, S B Hur & J-Y Jo

Abstract

High mortality frequently occurs in larval mass production of Korean rockfish,
Sebastes schlegeli Hilgendorf. Nutritional deficiencies in live feeds, rotifers and
Artemia nauplii, fed to larvae could be a reason. A series of experiments was carried out to evaluate the effect of nutritional enrichment of live feeds by ω-yeast, Spirulina powder and Super SelcoTM on survival and growth rates in rockfish larvae. Preference of rockfish larvae for the live feeds was determined by analysis of stomach contents. In addition, the effect of green water produced by the use of Chlorella ellipsoidea and Spirulina powder on the growth performance of larvae was evaluated. Larvae fed rotifers nutritionally enriched with Super Selco showed significantly higher survival rates than those fed rotifers enriched with ω-yeast. Larvae fed rotifers that were nutritionally enriched with both Super Selco and Spirulina together exhibited improved growth and survival rates. Larvae fed Artemia nauplii nutritionally enriched with Spirulina powder showed significantly higher survival than larvae fed Artemia nauplii without enrichment. When larvae were fed rotifers, Artemia nauplii or the mixture of rotifers and Artemia nauplii, the second and
last group showed significantly higher survival than the first group. Fatty acid
composition in live feeds was improved by enrichment of ω-yeast and larvae fed this feed showed higher survival and growth rates compared with larvae fed non-enriched feeds. No positive effect of green water in the tank produced with C. ellipsoidea or
Spirulina powder was observed on survival and growth rates for larvae fed nutritionally enriched rotifers with Super Selco and Spirulina powder. However, when the larvae were fed Artemia nauplii that were nutritionally enriched with ω-yeast and Spirulina powder, green water obtained by adding Spirulina powder to the tanks resulted in significantly higher growth rates of larvae than was obtained by adding C. ellipsoidea.

Extracted from:
Aquaculture Research
Volume 32 Page 199 - March 2001
doi:10.1046/j.1365-2109.2001.00547.x
Volume 32 Issue 3

Abstract Source
http://www.blackwell-synergy.com/doi...2rotifer%22%29

HTH