G'day gents, please allow me to introduce myself, and add my Canadian 2 cents worth to this discussion.
First off I will preface my following comments by stating up front that while I do have a vested interest in the fish food industry, I have a much larger vested interest in keeping my fish healthy. I'm not here to hard sell anything, to anyone, only to clear up what I see as a great deal of misinformation on the subject of garlic, and fish feed.
Some pretty strong stuff here - garlic kills fish - It's a GIMMICK that helps to sell fish food - hijacked by the sales/advertising people in the aquarium hobby industry (who most likely have NO IDEA of what it actually is/does), just because of it's money-making potential...
I would like to start by addressing the comment below;
These are obviously FRESH water fish...
Actually no, these would be marine fish, some of them considered to be ultra sensitive, and "doomed in captivity" by many hobbyists. Fish such as Moorish Idol, Rock Beauty, Majestic Angels, Achilles Tang, etc.
Pablo Tepoot has been keeping marine fish most of his life, and at near 70 yrs of age, with approx 5,000 gallons worth of SW running in the tanks at his home, and having authored a book on marine fish, I think that it's safe to say that he knows a thing or two about keeping marine fish thriving in captivity. And yes, he also keeps a few freshwater fish. His farm consists of ...... 120 ponds (approximately 30,000 gal. each), 1500 concrete vats (250gal.-500gal. each) and 1,000 40 gal. fry tanks.
I think you'll be hard pressed to find another fish food manufacturer that has the personal "hands on" experience as Pablo Tepoot, be it with marine, or freshwater fish.
The internet is a wonderful thing, I'm young enough to take it for granted, and old enough to know that the info one finds is only as good as the source that supplies it.
With all due respect to Wombat, allow me to counter his/her various comments that were posted above.
Most terrestrial plants have a completely different lipid profile for what is required by marine fishes causing heart and liver lesions
While this is very true, I think that a very important part of this equation has been left out, that being the inclusion rate of lipids via the addition of adding garlic to most commercial feeds (@ 1-5%) wouldn't even register on the overall lipid percentage of the food.
I don't know of any manufacturers adding
massive amounts of garlic to their commercial feed, so please let's not judge all products that may contain garlic, as a single entity. With regards to commercial foods, the "lipid" content derived from the garlic used in most formulas (garlic powder), would be almost nonexistent. Something along the lines of 0.0001%
To think that this will somehow have negative effects on the health of a fish, be it short term, or long term, due to the lipid content, is quite frankly, ridiculous.
Using this same type of logic one could make the same accusations about Vitamin A, due to the fact that at high enough levels it too can become toxic to fish. No nutritionist would recommend completely eliminating vitamin A, B, D, E and K from the diet based only on the fact that at inappropriate levels it can be harmful and evenly deadly to a fish.
Please keep in mind that almost
everything and anything can become toxic at high enough levels.
Trust me, no manufacturer of dry fish foods is adding
400ug/kg of purified allacin to their feed, such as in your feed trials. And even if at some point one manufacturer does, that doesn't mean that everyone should suddenly throw out ALL the babies with the bath water!
Run several controlled feed trials using lipids from marine sources, such as what some of these fish would experience in the wild, yet in excessive amounts, and I can assure that those results will be quite damning as well. Does excessive fat deposition in the viscera & tissues leading to progressive degeneration of liver cells, sound about right?
It all boils down to proper balance, and moderation. Remove one strand from a woven basket, and the whole basket can unravel.
The reports that were posted above by Wombat have to do with fish raised for human consumption, and the terrestrial lipid content is obviously very high in those studies as the commercial fish farms are constantly in search of reducing feed costs via the removal of fish protein & fish lipids, and replacing them with grain & grain by-products. This is precisely why these tests took place. They are looking for less costly alternatives! Also, most commercial salmon operations tend to use fairly high lipid content in their feed to ensure that the more costly protein (fish meal) is spared for growth, and not utilized as an energy source.
The studies that were posted above have simply shown what can happen IF one feeds excessive amounts of these lipids to those species of fish. But again, these studies have nothing to do with garlic inclusion rates in food, and the resulting lipids that would be present from that particular food stuff (garlic powder) in a commercial food.
This type of "commercial farm" research has been taking place for decades, due to the largest expense of most commercial operations being the cost of the feed. If one can reduce the overall feed costs, or lower the feed conversion ratio, on larger farms those savings can equal hundreds of thousands of dollars. (in a single year!)
So the farms keep running tests & studying the results in the hopes that one day they can replace the majority of the more costly marine proteins (fish meal & fish oil) with less costly grain & grain by-products.
And no offence to Steven Pro, but in my humble opinion the author has used a rather broad brush when referring to commercial manufacturers. Also, some of the info in that article is now somewhat outdated. Steven Pro's article was based on nothng more than one persons
personal opinion, on a subject that he is most certainly not qualified to speak on as any type of expert.
Over the past decade there has been a number of studies involving garlic and fish food and the anecdotal evidence with regards to feeding fish allicin complex (the active ingredient in garlic) to rid them of parasites appeared to be quite strong. The following is a link to a more recent study that confirms what some people have been saying all along.
http://www.scielo.br/pdf/jvatitd/v12n2/v12n2a03.pdf
A. M. Shalaby et al. EFFECTS OF GARLIC (Allium sativum) AND CHLORAMPHENICOL ON GROWTH PERFORMANCE, PHYSIOLOGICAL PARAMETERS AND SURVIVAL OF NILE TILAPIA (Oreochromis niloticus).
J. Venom. Anim. Toxins incl. Trop. Dis., 2006, 12, 2, p.196
Fish Hatchery and Reproductive Physiology Department, Central Laboratory for Aquaculture Research, Abbassa, Abo-Hammad, Sharkia, Egypt
In this particular study the inclusion of garlic powder at a rate of 3% has shown to increase the overall digestibility of protein, carbohydrates, and fat, as well as to lower the total bacteria count within the intestine, muscles, as well as the tank water itself.
And another recent study ...............
Effect of Allium sativum on the immunity and survival of Labeo rohita infected with Aeromonas hydrophila
S. Sahu, B. K. Das, B. K. Mishra, J. Pradhan and N. Sarangi
Aquatic Animal Health Division, Central Institute of Freshwater Aquaculture, Kausalyaganga, Bhubaneswar, India
Wiley InterScience :: Session Cookies
Summary
The aim of this study was to evaluate dietary dosages of garlic on the immune response and disease resistance against infections due to the opportunistic pathogen Aeromonas hydrophila in Labeo rohita fingerlings. Garlic, Allium sativum, was incorporated into the diets (0%, 0.1%, 0.5% and 1.0%) of rohu, L. rohita fingerlings (10 ± 2 g). Every 20 days, different biochemical (serum total protein, albumin, globulin, albumin : globulin ratio, blood glucose), haematological (WBC, RBC and haemoglobin content) and immunological (superoxide anion production, lysozyme activity and serum bactericidal activity) parameters were evaluated. Superoxide anion production, lysozyme, serum bactericidal, serum protein and albumin were enhanced in garlic treated groups compared with the control group. After 60 days, fish were challenged with A. hydrophila and mortality (%) was recorded up to day 10 post-challenge. Survival decreased in control group (57%) up to day 10 after infection. However, this was increased in the garlic treatment group, i.e. 85% survivability in the 1 g garlic kg−1 (B group) and 5 g garlic kg−1 (C group), and 71% survivability in the 10 g garlic kg−1 (D group), respectively. These results indicate that Allium sativum stimulates the immunity and makes L. rohita more resistant to infection by A. hydrophila.
FYI - I have personally seen numerous marine fish (including some very delicate species) that have consumed garlic via commercial food for 10+ yrs, with no ill effects. Quite the opposite actually, a decade later & these same fish were still thriving in captivity.
So I wouldn't be so quick to judge with regards to garlic not being an immunostimulant in fish. What Pablo Tepoot has been stating about garlic for the past 15+ yrs, science is just recently catching up with.
Some of the most prestigious public marine systems in North America feed commercial food that contains garlic. Joe Yaiullo, one of the pioneers of reef keeping in the USA, and the curator/co-founder of Atlantis Marine World in NY has been feeding such a dry food for
several years. You can view his 20,000 gallon reef set up (the largest reef tank in North America, and 4th largest in the world) in the link below, where he also mentions the various feed that he uses.
Advanced Aquarist's Online Magazine - Featured Aquarium: Atlantis Marine World
Joe Yaiullo is one of the world’s most highly regarded Aquarium authorities. He has consulted with many public Aquariums worldwide, and has also presented reef-keeping lectures throughout the United States, Canada, and Europe.
Bob Fenner, who is widely known through his various published works on marine aquatics, as well as his wetwebmedia website, has openly stated that a commercial brand of feed (that contains garlic) is not only a nutritionally complete food, in his opinion it is the best food, period. Even though he has no financial interest whatsoever in this product, or the parent company. Go figure.
Recently Charles Delbeek M.Sc., senior biologist at the Steinhart Aquarium in San Francisco has also begun feeding a commercial food (that contains garlic) at their facility, and these are just a few examples of some of the more advanced marine keepers in the USA that apparently are having very positive results with these commercial formulas.
To quote a long term mentor of mine - "an expert is someone who knows so much, they have no room left in their head to learn anything new".
cheers
