Grow Outs

[RDFISHGUY]

Are there any studies to be found that discuss the correlation between beef and liver disease in fish, that someone could point out?

What do Discus eat?

I have examined hundreds of specimens during many years and stomach and gut contents among wild Discus indicate an order of precedence: detritus, then plant material (flowers, fruits, seeds, leaves), algae and micro-algae, aquatic invertebrates and terrestrial and arboreal arthropods.

The Amazon has adapted to nature for fishes during millennia of evolution. Plants of the tropical rainforest have little water and cannot flourish during the dry season so cannot waste energy. The same happens to most freshwater fishes.

During the dry period, with a much reduced water level and hardly any food source — except for predators — many fish starve or feed on the little available, usually detritus.

Discus and many other fishes eat what they can get, but have to be constantly aware of carnivorous predators.

During the six to nine months of floods, almost all trees and bushes, flower and have fruits and seeds — which is the main nutrition of roughly 75% of all Amazonian fishes.

The adults, and babies which grow to adults in that period, can then fill their stomachs and guts.

The carnivorous predators starve as they cannot find their prey in the huge water masses.

How much nutrition?

I have found the following percentage of nutrition in each one of the three species:

•Symphysodon discus during low water: 55% detritus; 15% plant material; 12% algae and micro-algae; 10% aquatic invertebrates; 8% terrestrial and arboreal arthropods. During high water: 28% detritus; 52% plant material; 5% algae and micro-algae; 3% aquatic invertebrates; 12% terrestrial and arboreal arthropods.

•Symphysodon aequifasciatus low water: 52% detritus; 18% plant material; 15% algae and micro-algae; 13% aquatic invertebrates; 2% terrestrial and arboreal arthropods. High water: 8% detritus; 62% plant material; 8% algae and micro-algae; 5% aquatic invertebrates; 17% terrestrial and arboreal arthropods.

•Symphysodon haraldi low water: 39% detritus; 9% plant material; 25% algae and micro-algae; 22% aquatic invertebrates; 5% terrestrial and arboreal arthropods. High water: 6% detritus; 44% Plant material; 12% algae and micro-algae; 16% aquatic invertebrates; 22% terrestrial and arboreal arthropods

Heiko Bleher

I also read some other articles that suggest seafood makes a better protein source than beefheart. There is very little meat protein in their diet period.

http://nutritiondata.self.com/facts/beef-products/3464/2

http://nutritiondata.self.com/facts/finfish-and-shellfish-products/4172/2

Although I couldn't find a study specifically about beefheart and discus, from the research I've done I can surmise 3 things:

1. Cold blooded animals cannot easily assimilate warm blooded protein fats.

2. Beef heart is a warm blooded animal protein relatively high in saturated fats.

3. I am dyslexic. I thought your post said discus not discuss. LOL. :drunk:

I also read that fatty liver disease can be reversed in humans if the diet is changed. Can it be reversed in fish? If so it could be used when fish are young but prolonged use would likely be fatal.

Edited December 16, 2010 by RDFISHGUY

[dunl]

3. I am dyslexic. I thought your post said discus not discuss. LOL. :drunk:

LMAO. -roll-

I also read that fatty liver disease can be reversed in humans if the diet is changed. Can it be reversed in fish? If so it could be used when fish are young but prolonged use would likely be fatal.

Just not quite sure what you mean Ryan by the last sentence....correct me if I am wrong, but you are saying that liver disease can be reversed in fish if caught early enough....right?

[RDFISHGUY]

No, I am saying it can be reversed in humans. This then poses the question, "Does mamallion meat leave an irreversable fatty liver build up because it cannot be assimilated properly or will it heal itself when the fatty foods are taken away?"

IF it does heal itself then you could feed it to younger fish to get them to grow quicker as Hustler suggested. I think you would have to get a group of test subjects and feed them the beefheart a certain amount of time and then cut them off and examine one specimen per month until either: A) all of the fish are dead or you no longer see evidence of the disease. You would also need another group of test subjects fed no beefheart to see which group of test subjects live longer.

I am certainly not going to be subjecting my fish to that. If anyone wants to give it a whirl go ahead. Based on existing evidence, I will not include beef heart in the diet of any of my fish. I am not a scientist but I would say any stress to the organs for any amount of time would likely cause shorter life. Kind of like smoking. I smoked for 20 years but now that I've quit I don't expect to live as long as I would if I hadn't taken up the habit. :bang1:

[dunl]

No, I am saying it can be reversed in humans. This then poses the question, "Does mamallion meat leave an irreversable fatty liver build up because it cannot be assimilated properly or will it heal itself when the fatty foods are taken away?"

IF it does heal itself then you could feed it to younger fish to get them to grow quicker as Hustler suggested. I think you would have to get a group of test subjects and feed them the beefheart a certain amount of time and then cut them off and examine one specimen per month until either: A) all of the fish are dead or you no longer see evidence of the disease. You would also need another group of test subjects fed no beefheart to see which group of test subjects live longer.

I am certainly not going to be subjecting my fish to that. If anyone wants to give it a whirl go ahead. Based on existing evidence, I will not include beef heart in the diet of any of my fish. I am not a scientist but I would say any stress to the organs for any amount of time would likely cause shorter life. Kind of like smoking. I smoked for 20 years but now that I've quit I don't expect to live as long as I would if I hadn't taken up the habit. :bang1:

I suppose that would depend on the regenerative abilities of the affected areas. There are rare cases of humans having heart defects or other organs, that somehow repair themselves over the years.

[RDFISHGUY]

Yeah and my lungs will repair themselves, providing I don't already have cancer in them, but that doesn't mean I am going to live as long as if I never smoked.

The fact is even if it can regenerate how much of a toll has the damage put on the body. Is it ever the same after? If you think it is safe then feed it to your fish but I would not advise anyone to do so. You don't even know if the condition can be reversed in fish. Remember they can't assimilate mammal protein the same way we can. Once the damage is done it may not be undone. I keep fish that can live a long time and I'd like to keep it that way.

[RD.]

The only reason I brought up beefheart in the first place is that it is still commonly used in asia and lots of Gro Outs around the world due to remarkable size growth when its fed to catfish IE Paroon sharks..... Much like discus ect ect.

Beefheart is fed by certain breeders because it's a very cheap source of protein, and it does create quick growth, but just like commercial fish operations these breeders are not concerned with longevity, only how quickly they can bring their fish to market.

Many "monster" fish keepers do the same in a rush for massive quick growth, not realizing what the long term affects on the health of the fish may be. Even the person who many consider the Godfather of Discus, Jack Wattley, no longer feeds beefheart to his fish, and a few years ago stated in a TFH article that pellets & flakes provide just as good results in his grow outs, and adult breeders. You can read more on that subject here:

http://albertaaquatica.com/index.php?showtopic=25190

and here:

http://albertaaquatica.com/index.php?showtopic=29550

When you consider the fact that catfish such as Pangasius sanitwongsei are known to live 15-20 years in captivity, one should take into account the whole picture, not just what one can produce in size within the first 2-3 yrs of the fishes life. If Raymond's Lima Shovelnose, Indo Dat, Red Tail Giant Gourami and Bocourti, can all swallow a 10mm pellet down in one gulp, then I think that it's safe to say that your catfish can as well.

The key to training a fish for a comm tank such as yours, is to train them when they first arrive & are in a QT tank for the first few weeks. Not only can you monitor their health before exposing any potential pathogens to your comm tank, but during this period you can train them to eat whatever you want. Most catfish will eat cornmeal & molasses dough balls (and I've caught plenty of Channel Catfish to prove it), so almost anything that even remotely smells like food will eventually become their diet, all it takes is some patience on the part of the person training the fish. If you decide that pellets aren't for you, then that's fine too.

I originally posted the following information several years ago, and while it doesn't involve feeding beefheart, it does explain what can happen to a fish fed excessive amounts of fat, even when the fish are very young juveniles. The author/s of this paper are considered by many to be experts in the field of health & nutrition of tropical fish.

..........................................................................................

The following paper was sent to me & although you need a subscription to read the entire study, the link provides a brief abstract, and I've added a bit more detail below.

http://afsjournals.org/doi/abs/10.1577/A03-035.1?journalCode=naja

Keep in mind that the info in this report was relating to juvenile African cichlids, that were only 4 weeks old at the start of this 12 week feed trial.

Even with very young fish, who require higher levels of both protein as well as fat (due to higher metabolisms), the higher lipid (fat) content found in the trout pellet diet (TP) caused these young fish to develop fatty livers, within a very short period of time.

Also, from this report;

"Fatty infiltration of the liver has also been designated "the most common metabolic disturbance and most frequent cause of death in aquarium fish"

Now imagine what happens to the liver of an adult African cichlid when fed diets that contain excessive amounts of lipids. The juvie H. ahli (s. fryeri) used in this study faired much better being a carnivore, but it still showed a lipid accumulation in the hepatocytes. (<50%) The P. socolofi had extensive lipid accumulation when fed this TP diet.

With prolonged feeding of a high-energy, lipid rich diet, degenerative changes of the liver and death can occur unless the diet is corrected. (Ferguson 1989; Tucker et al. 1997)

Those here that know me know that I've been harping about this for some time, but perhaps when people read it first hand from a study performed by the Department of Fisheries and Aquatic Sciences at the University of Florida, they'll understand why I never recommend using some of these various fish foods that are over 10% in crude fat. (for freshwater fish)

The connection between excessive lipids & fatty liver disease has been common knowledge in the aquaculture industry for many years, but the interesting part about this study was that it involved African Cichlids, which as far as I know is a first.

Suddenly foods that have 10-14% crude fat (min), don't look too appealing as an adult maintenance diet, do they?

The photos showing sections of the livers of these young fish after being on a high fat diet was quite an eye opener. :shock:

This study came about after some cichlid farms in south FL suffered from some large mortalities in both 1998 & 1999. When the dead fish were examined they showed fatty infiltration of the liver, heavy vacuolation, and severe necrosis of the liver, pancreas, and spleen.

It was suggested to the farms that they replace there feeds with one that had a lower lipid content (less than 10%) and supplement the feed with a vitamin premix. Clinical signs in the affected farms were resolved after implementation of these recommendations.

.................................................

And last but not least ........

The problem with people stating opinions in such a way on these forums is that it appears that they are stating facts, not opinions.

I could understand that, Darcy, if I was some teenage kid who had a habit of talking out of my arse, but you've known me for years, and as you are well aware this is certainly not my first rodeo. In all the hundreds/thousands of posts that I have made on the subject of fish nutrition over the years I think that you would be very hard pressed to find a discussion where I was making things up as I went along. Over the years I have been invited to speak on the subject of fish nutrition & health on various forums around the world, asked to moderate health/nutrition folders on several forums (to which I have always declined due to what I feel could be considered a conflict of interest) and was recently asked to join Bob Fenner's team of advisors on Wetwebmedia (directly due to my knowledge on the subject of fish nutrition), to which I also declined.

Over the years I've swapped spit with the best of them, including manufacturers, company reps, marine biologists, zoologists, DVM's, PhD research scientists that specialize in the field of fish nutrition, that have enough letters after their name to sink a ship. I'm not saying that I know it all, because I don't, but I don't expect to be "called out" if I make a statement regarding fish nutrition. I'm rather certain that the creator of this forum didn't bestow me with A-A Mentor status because of my misleading comments to fellow members of this forum.

This forum is made up of hobbyists, and as such we all come here for the same reasons, to share our experiences, knowledge, and opinions, and hopefully to help fellow members. I don't expect that any member here should be required to qualify every comment or opinion that they make with a link to a study, journal, or peer reviewed paper, even if the Mod of War personally considers the comment has been posted in a factual manner. (without data to support those comments)

It wasn't that you asked, Darcy, it was the manner in which you asked, as in your constant badgering for a definitive answer. Using language such as "RD's little research assistant", to Cursive Duck, who was only offering their assistance, was IMO certainly not called for either.

Perhaps in the future a more tactful and respectful approach would be to do your own research, and find your own studies to prove otherwise, if you feel someone's comment may be misleading to other forum members.

Cheers

[dunl]

You could have just posted the above info when asked. After all, it IS helpful information.....I have no idea why you wouldn't share it.

[RD.]

In case you missed it, the study linked to above does not involve beefheart, or any form of BEEF.

Seeing as you were rather adamant about "studies to be found that discuss the correlation between beef and liver disease in fish" ....... at the time I didn't see any point in addressing excessive fats from other dietary sources, or posting links to same. I'm only posting it now, due to some of the more recent comments posted by Ryan.

But you already knew that.

Good luck with that shiny new moderator badge.

Over, and out.

Edited December 16, 2010 by RD.

[CursiveDuck]

Seeming as I had sometime on my hands, and regardless of the issues endured for offering to help. I have located an article assessing the subject matter a tiny bit but not completely. Article:

Assessment of dry matter and protein digestibilities of selected raw ingredients by discus fish (Symphysodon aequifasciata ) using in vivo and in vitro methods.Full Text Available By: CHONG, A.S.C; HASHIM, R; ALI, A.B. Aquaculture Nutrition, Sep2002, Vol. 8 Issue 3, p229-238, 10p; DOI: 10.1046/j.1365-2095.2002.00214.x

There is a fat analysis done but the correlation between the fat digestibility and type of feed is nonexistent. Yet the article is great in that it does point out that in terms of dry matter digestibility and protein digestibility, fish meal still is more digestible in Discus than beef heart.

In regards to dry matter digestibility:

In general,these in vitro methods revealed that dry matter digestibility was highest in casein or fish meal,followed by beef heart or soybean meal while both poultry offal and wheat meal tend to show the lowest digestibility values.

In regards to protein digestibility:

In vivo results of protein digestibility for all ingredients analysed were high,ranging from 63 to 96%. Casein showed the highest protein digestibility,followed by fish meal, soybean meal and beef heart while both poultry offal and wheat meal gave the lowest protein ADC values (Table 4).

This is in regards to the low digestibility of chicken meal, but does give a good quotation to as why high fat%'s are not good in feed, and would in fact also work towards beef which has the second highest fat content of this experiment:

In addition,the high lipid content (28.17%) of this meal could have also lowered the overall protein digestibility because of the formation of protein and oxidized fatty acid complexes which negatively affects protein hydrolysis rate (Murray et al. 1977; Ufodike & Matty 1983; Sullivan &

Reigh 1995).

Though in terms of digestibility alone:

Asian farmers commonly use raw beef heart as the main ingredient in preparation of moist feeds as a discus growth out diet. The good digestibility values obtained here for dry matter (in vivo: 75.89%; in vitro: 55.08–79.50%) and protein (in vivo: 72.96%, in vitro: 62.23–73.16%) showed that this ingredient could be utilized as a major dietary protein source for commercial discus farming

This article does acknowledge that beef heart is a good source of protein digestibility, which could be inferred to explain why it is used in commercial pratices to help grow Discus, its cheap and works. Yet this study does in fact prove that Discus more readily digest fish matter, and fish itself is a better source of both digestibilities. Using this knowledge you can infer that fish meal is a better food source then beef heart. Though without further study into the fat decompositions, and how a discus handles the excess fat that the beef heart contains, it is hard to say whether or not beef heart is actually a good food source. But as the others studies from RD and REDFISHGUY show, excess fats in a fish's diet will lead to fatty liver disease, or complications. I do not think it to far out to say that if fish has better digestibility, better protein digestibility, and less fat content, that it would be far better to feed your fish, fish, instead of beefheart.

[dunl]

Thanks for looking that up. There's some excellent material in there. It would be nice to see something regarding the fat content and its effect on liver function and liver health, but this is great. Maybe over the holidays I will see what I can search out.

[CursiveDuck]

I'm headed to Vancouver tomorrow, so I have to pack today. But it will be a lazy holiday for me with hundreds of databases to browse. I found the discus article cause it was brought up earlier, but I will try and find an article relating the two as well, it just may not be specific to Discus. I dunno if you have ever used Google Scholar at all, but just remember your AND or OR between fish AND liver disease AND beefheart. It'll make life a thousand times easier for you when your searching through it all. Luckily the universities have their databases set up nicely so I don't have to worry about text formatting lol :P