Yes Azad sir truly said....but the results are varying and no conclusive outcome can be drawn based on a species. It may differ from species to species and the prevailing environmental conditions. As far as I know research approach should be focused on identifying probiotic organisms of endogenous origin. The trend in today's research on probiotics does not assist the requirement of present science. Now a days the modern concept of synbiotics has to be given priority through combination approach of the already approved probiotics.

Hi Azad, you are quite right.

I think the reason for these observations are not far fetched;

1. species differences (Fresh water, brackish and Marine); age (fingerling, juveniles and adults)

2. Differences in the type and number of Probiotic organisms tested by each study (single organism or a cocktail)

3. Length of study (from a few weeks to a few months)

4. The indices used to arrive at conclusions (blood parameters, feed efficiency, Growth or any cobination of these).

There are a lot other considerations which space may not permit me to list.

However, our paper is one of the most cited (25 times so far, in 3 years) in Aquaculture Research which reported probiotics effects in African catfish;

(Mohammed Abdullah Al-Dohail, Roshada Hashim and Mohammed Aliyu-Paiko [2009] Effects of the probiotic, Lactobacillus acidophilus, on the growth performance, haematology parameters and immunoglobulin concentration in African Catfish (Clarias gariepinus, Burchell 1822) fingerling. Aqua Res. 40, 1642-1652)

This is so because;

1. We selected and concentrated on the effects of one probiotic bacteria species based on certain factors

2. We carried out preliminary studies to ensure it works and then went ahead to run the experiment for a long time (stocked the fish and grew them to harvest size)

3. We used a large sample size and measured both growth and feed efficiency, as well as several blood parameters to arrive at our conclusion.

Therefore, the choice of which probiotic to apply is surely based on the choice of the right factors and considering many variables. Nonetheless, my one dollar assurance to you is that probiotics really work, as we have convinced farmers to use it and they have reported success stories.

I have one observation that I wish to share with you all. Yes, as Dr. Singh and Dr. Mohammad have rightly put, there are lot more variations in the aquatic host species when compared to the terrestrial animals. We need to go in for finding a suitable autochthonous probiotic.

We isolated a probiotic GP bacterial from the gut of yellowfin bream (Sparid) it gave good positive results on growth and survival in larval stages. It persisted longer in the gut compared to the PB sp tested in terestrial animals.

The same probiotic was tested in blufin bream (very close relative of the YFB). There was an interesting result. The added probiotic was there in the gut for lesser time in the gut but later helped in proliferation of another bacterial in the gut which had stronger anti-vibrio propeorties than the originally added. However, it had lower growth effect but higher immune enhancements.

Was the first species acting as a pre-biotic for the latter...!!!?? these are interesting observations.

Hello Azad, looks like you got some exciting results there.

However, the prebiotic concept is quite different. It has to be an additive which is

1. Not digested in the GIT of the animal, as such survives all the enzymes in the GIT

2. Is fermented by LAB strains, to possibly increase energy or nutrients to the animal

This is the reason why substances called prebiotics are usually indigestible oligosaccharides like inulin, fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS) and others like that. The list of prebiotic substances keeps increasing and lately, we stumbled on a polysaccharide from marine source which we think shows strong prebiotic characteristics and we are working to carry out all the tests to be sure. We are about 90% there.

I think what you noticed could likely be a symbiotic! Although defined to be the synergy between a prebiotic and a probiotic, there are also reports that symbiosis occurs between probiotic bacteria of different strains (although this is not mentioned in the symbiotic definition). If you guys can work on what you stumbled on, maybe it could add some more information to the probiotic concept, which is currently a hot topic in animal nutrition. Listen to this;

"Gibson and Roberfoid (1995) introduced the prebiotic concept. According to them a prebiotic is 1) a non-digestible food ingredient 2) that beneficially affects

the host 3) by selectively stimulating the growth and/or activity of one or a limited number of bacteria in the colon, that can improve the host health' "

(G. R. Gibson, M. B. Roberfroid, J. Nutr. 125 (1995) 1401–1412)

However in my opinion, the attachment of one probiotic bacteria promoting or enhancing the attachment of another strain makes a lot of sense. The relationship between the surface binding proteins on probiotic are reported to be similar among some strains of LAB. This may therefore account for the similarity in their binding to the mucins on the epithelial cells of the same fish or to the mucus as the case may be.

It sounds like an interesting find there, but must be analyzed properly to educate the scientific community.

Good luck

Dear Learned

The forum discusses very interesting question with satisfying answers. A suitable environment both physical and chemical is required for survival of any organisms in the intestine. The culture system also plays a role along with the candidate species cultured. So if a probiotic microbe survives and proliferates in the intestine we can expect a better result. The gut environment like pH, enzyme level will vary according to species and so the performance of probiotics. So Dr. Azad got two different results.

Now the concept is moving from probiotic to prebiotic so that a conducive environment is created inside the intestine through feed ingredients alteration. It has been established very well in livestock and picking up in aquaculture. In my view, both probiotic and prebiotic concepts are of advanced one which could be proved only under biosecured culture units. A simple addition like organic fertilizer / vermicompost may give better bacterial and fungal mix for carps/ tilapias.

Everything has to be evaluated for a particular species.

Here you are:

http://www.intechopen.com/books/probiotic-in-animals/use-of-probiotics-in-aquaculture

Dear Gomez, thanks for the link. infact we too had a chapter in the same Intech Publication (I have given a link here in RG).

If results seems not conclusive, it can be a good signal to perform a Meta-Analysis. This tool is useful to obtain a summary effect of the treatment, the variance of true effects of the treatment and also can give a direction for analysis of reasons of heterogeneity in results...