Goldfish are Nutritious
- Thread starter sjkoi
- Start date
no one asked anything about you.....lol, all i asked is your proof. you created a thread and have failed to provide any substance. now it appears you wanted others to make the case for you?
I personally think this guy is a troll. He keeps acting like he has aquired various facts, names, and information, yet I have not seen one single fact. Although there have already been many posts against his claim, he would rather respond about him being immature, and completely ignore everything being said against his claim.
P.S. I think feeders can be used as a treat(if you are into watching living things be uneccesarily murdered) if they are properly bred/quarantined and gut loaded on nutritional pellets. But even this, should be a treat, once a month type of treat.
P.S. I think feeders can be used as a treat(if you are into watching living things be uneccesarily murdered) if they are properly bred/quarantined and gut loaded on nutritional pellets. But even this, should be a treat, once a month type of treat.
"Nutrition Advisory Group Handbook", Fact Sheet 005, September 1997 (modified March 2002) Authors Joni B. Bernard PhD Department of Zoology Michigan State and Mary E. Allen PhD National Zoological Park Smithsonian Institution Washington DC.
*Note - this paper was written as a guideline for the feeding of animals in zoos and public aquariums. The discussion references dead or frozen fish. An important distinction to keep in mind when discussing uptake of vitamin E and Thiamin (B1). Actually a critical distinction as I have come to understand.
"Whole fish are relatively good sources of most nutrients, and similar to other whole prey items, typically containing a substantial concentration of protein (40-80% on a dry mater basis (DMB)). Ether extract, an estimate of fat, is highly variable within and among fish species, ranging from about 2-50% (DMB), depending upon physiological stage, diet, and season... Most fish species are a valuable source of major and trace minerals."
"Some species of fish may contain very high concentrations of the fat-soluble vitamins A and D. Vitamin E probably also occurs in ample amounts in fresh fish; however, since it is a natural antioxidant and fish oils oxidize readily, much of the vitamin E originally present may be destroyed prior to feeding."
"Wild pinnipeds and cetaceans, as well as piscivorous birds, reptiles, amphibians, and fish, feed on a wide variety of fish species... therefore, the recommended method of feeding most piscivorous animals is to feed at least three, and preferably more, species of fish."
"Thiamin and vitamin E are nutrients that are known to be limiting or problematic in fish and marine invertebrates. Both of these are relatively quickly degraded in killed fish, even when fish are frozen under ideal conditions"
"The nutritional value and composition of fish is greatly dependent upon proper shipping, storage and handling. Even under ideal freezer conditions, denaturation of proteins, rancidity of fats, denaturation of vitamins, and dehydration may occur."
Proximate analysis and content of whole fish
Goldfish - Crude protein 58.8%, fat 8.5%, energy 4.15 Kcal/g, Ca 6.99%, P 4.36%, Mg 0.17%, Na 0.65%, K 1.22%, Cu 14 ppm, Fe 307 ppm, Zn 225 ppm, Mn 64 ppm, Se 1.22 ppm
Minnows - Crude protein 64.6%, fat 14.1%, energy 4.97 Kcal/g, Ca 3.71%, P 3.01%, Mg 0.19%, Na 0.59%, K 1.38%, Cu 13 ppm, Fe 225 ppm, Zn 165 ppm, Mn 17 ppm Se 0.82 ppm
Rainbow Trout - Crude protein 54.7-68.5 %, fat 27.2-33.9 %, energy 5.68-6.15 Kcal/g, Ca 1.68%, P 1.66%, Mg 0.10%, Na 0.25%, K 1.46%, Cu 7 pm, Fe 51 ppm, Zn 113 ppm, Mn .5 ppm Se .86 ppm
This was an interesting paper and the only reference to nutritional content of whole goldfish I have ever come across or seen referenced. More work could and should be done since nutritional profiles can vary widely within species. These numbers should be the basis for any future discussion on the fat content of goldfish once someone else verifies my source. Tomorrow i will give my best analysis of the impact of thiaminase on diets. My assumptions were turned upside down after discussing it with a scientist with USGS who studies the issue and its impact on lake trout.
*Note - this paper was written as a guideline for the feeding of animals in zoos and public aquariums. The discussion references dead or frozen fish. An important distinction to keep in mind when discussing uptake of vitamin E and Thiamin (B1). Actually a critical distinction as I have come to understand.
"Whole fish are relatively good sources of most nutrients, and similar to other whole prey items, typically containing a substantial concentration of protein (40-80% on a dry mater basis (DMB)). Ether extract, an estimate of fat, is highly variable within and among fish species, ranging from about 2-50% (DMB), depending upon physiological stage, diet, and season... Most fish species are a valuable source of major and trace minerals."
"Some species of fish may contain very high concentrations of the fat-soluble vitamins A and D. Vitamin E probably also occurs in ample amounts in fresh fish; however, since it is a natural antioxidant and fish oils oxidize readily, much of the vitamin E originally present may be destroyed prior to feeding."
"Wild pinnipeds and cetaceans, as well as piscivorous birds, reptiles, amphibians, and fish, feed on a wide variety of fish species... therefore, the recommended method of feeding most piscivorous animals is to feed at least three, and preferably more, species of fish."
"Thiamin and vitamin E are nutrients that are known to be limiting or problematic in fish and marine invertebrates. Both of these are relatively quickly degraded in killed fish, even when fish are frozen under ideal conditions"
"The nutritional value and composition of fish is greatly dependent upon proper shipping, storage and handling. Even under ideal freezer conditions, denaturation of proteins, rancidity of fats, denaturation of vitamins, and dehydration may occur."
Proximate analysis and content of whole fish
Goldfish - Crude protein 58.8%, fat 8.5%, energy 4.15 Kcal/g, Ca 6.99%, P 4.36%, Mg 0.17%, Na 0.65%, K 1.22%, Cu 14 ppm, Fe 307 ppm, Zn 225 ppm, Mn 64 ppm, Se 1.22 ppm
Minnows - Crude protein 64.6%, fat 14.1%, energy 4.97 Kcal/g, Ca 3.71%, P 3.01%, Mg 0.19%, Na 0.59%, K 1.38%, Cu 13 ppm, Fe 225 ppm, Zn 165 ppm, Mn 17 ppm Se 0.82 ppm
Rainbow Trout - Crude protein 54.7-68.5 %, fat 27.2-33.9 %, energy 5.68-6.15 Kcal/g, Ca 1.68%, P 1.66%, Mg 0.10%, Na 0.25%, K 1.46%, Cu 7 pm, Fe 51 ppm, Zn 113 ppm, Mn .5 ppm Se .86 ppm
This was an interesting paper and the only reference to nutritional content of whole goldfish I have ever come across or seen referenced. More work could and should be done since nutritional profiles can vary widely within species. These numbers should be the basis for any future discussion on the fat content of goldfish once someone else verifies my source. Tomorrow i will give my best analysis of the impact of thiaminase on diets. My assumptions were turned upside down after discussing it with a scientist with USGS who studies the issue and its impact on lake trout.
huh? you quote a 14 year old paper that didn't even support your claim?
it said thiamin is degraded in killed fish...not fresh live fish such as the feeders you're referencing? it even said it's problematic.
Also, people who feed market fish know not to use rainbow trouts or minnows too.....? we avoid red meats, it's fatty and fouls up your water
it said thiamin is degraded in killed fish...not fresh live fish such as the feeders you're referencing? it even said it's problematic.
Also, people who feed market fish know not to use rainbow trouts or minnows too.....? we avoid red meats, it's fatty and fouls up your water
Hey ill analyze the paper tommarow, but was just wondering where you from in California. Possibly from my area? (96150) I say this because the national forest service and other organizations are dealing with te impact if lake trout, and how to reintroduce the lahottan cut throat.
Bob,
I did not intend to skip your many good points. Each is a concern to me as well. I think with each approach to feeding fish there are trade-offs. The potential for introduction of disease into a freshwater tank is probably the most serious of your concerns. As you know though it is not a topic that can be pared down to a few simple posts. Water quality trumps disease in most cases as I was taught way back when. I don't want to ignore any of your points, but with your indulgence i want to first deal with the nutrition aspect. I'd also like to keep costs out of the discussion. I don't think that is the question here. I harvest about 60 gambusia a month from my koi pond filter at no cost to me. If I bought those same fish at the aquarium store it would cost me what, $6.00 or more. No small amount when you think of the cost per pound. Everyone's situation is unique, but the thrust of what I hope to explore here is what constitutes the best possible diet for piscivores. I am open to alternatives to live fish if someone can make the case that nutritionally there is a superior source of energy, protein, vitmins and minerals out there.
Rich
I am sorry, but it is the only one I could find and you are correct. As I noted, this paper references killed or frozen fish and was used to illustrate primarily that goldfish are low in fat and quite high in protein and minerals. In order to do the nutritional profile on a whole fish it would have to be dead, but your point brings up a bigger issue. In dead or frozen fish thiamin and Vitamin E levels should be considered as suspect and in need of supplementation. This is especially true in species of fish that contain the enzyme thiaminase, as most fish in the families clupeidae and cyprinidae do. In fact it could be generalized that many lower trophic species of fish do contain thiaminase either in their tissue or their guts. Upon freezing, or tissue degradation, the thiaminase will begin to degrade thiamin leading to nutritional deficiencies. That, for the most part, is where the story has ended in regards to thiaminase, but it gets a lot more interesting. A problem though is that the science needed to be done here is still evolving and incomplete. But, consider this, there is no record of thiamin deficiency in wild populations of warm-water species even when feeding on species containing thiaminase. I'll leave it at that for now, but that is why the science gets a little thin. There is no funding, because there is no problem to study.
Really? What "best science" do you have to support that? A simple crude protein or crude fat percentage doesn't prove anything. One would need to compare amino acid profiles, fatty acid profiles, total vitamin & trace mineral content, total digestibility, feed conversion ratios, color enhancing properties of the feed, a comparison of potential bioactive compounds contained in the food source, which in aquaculture have been shown to have biological effects in fish such as growth promotion, immunostimulation, anti-stress, anti-bacterial, anti-fungal, anti-virals. etc-etc-etc
So far I haven't seen you offer up anything of the sort. If you are just referring to growth, that's a different story. One can pump a fish up at lightning speeds using a cheap generic trout chow with a high protein high lipid content, but that type of growth comes with a hidden price tag, that being excessive lipid deposition in the liver, and premature death of the fish. If feeding live is what one chooses to do, there are far better options than goldfish. I would also like to point out that fat levels in feeder goldfish could vary vastly from one batch to the next, depending on various factors such as species, size/age, body condition, etc.
I have no problem with those that choose to feed live foods, but to state that other options are ridiculous alternatives, is well, ridiculous.
A past discussion on this subject regarding piscivores that some may find interesting.
http://www.monsterfishkeepers.com/forums/showthread.php?348258-Live-vs-Prepared-vs-Pellet
Two of the posters in the above discussion study & work with gars on a commercial level. Both of those gentlemen agreed with my comments in that discussion.
With regards to thiaminase ......
That's probably due to the fact that there aren't any warm water species of fish that only consume prey that contain large quantities of thiaminase. Their other various prey would likely contain enough B1 to negate any effect from those food stuffs that contain thiaminase.
Many species of fish & invertebrates contain thiaminase and when ingested in large quantities it destroys the natural thiamin (vitamin B1) which in turn can cause vitamin deficiency. In fish, vitamin B1 deficiencies can lead to stunting, illness, and premature death. Goldfish feeders are known to be high in thiaminase, as are shrimp/prawns, both of which are commonly used to feed large predatory species in captivity.
In the Great Lakes region, vitamin B1 deficiencies have also been the cause of a great deal of studies, and have been linked to both trout & salmon ingestion of alewifes & smelt, both known to be high in thiaminase.
http://www.glsc.usgs.gov/main.php?c...itiatives0&menu=research_initiatives_thiamine
With regards to both tropical & marine fish, the article below by Dr. Marco Lichtenberger is perhaps one of the best reads on this subject.
http://www.wetwebmedia.com/ca/volume_6/volume_6_1/thiaminase.htm
Cheers!
