INTRODUCTION:
There is a lot of confusion about what constitutes a quality flake food (or pellet). The aquarist needs to understand that there are similarities and differences between fish and other animals. For example; Fish get most of their energy needs from fat, but in humans carbohydrates are a better source. Another point is amino acids (the building blocks of proteins); almost all animals have different amino acid needs. For example; Cats need Taurine in there diet or they can suffer heart problems.
Then there is the speed of digestion, some fish such as goldfish tend to have slower digestive tracts (I like to compare it to a horse, but there are major differences such as the stomach). But the similarity is that if too high a protein or the wrong protein diet is fed, the horse may colic, and in goldfish they will build up intestinal gas and infections including swim bladder or dropsy will ensue. The wrong amino acids in any fish will lead to aquarium pollution (extra ammonia) and renal failure.
Another note about fish food is what carnivores need. Carnivorous fish often consume whole animals including intestinal contents, which often include plant material. A quality fish food for carnivores must include vegetable matter such as spirulina.
HERE ARE A FEW BUILDING BLOCK INGREDIENTS:
AMINO ACIDS:
An amino acid is any molecule that contains both amines (organic compounds that contain nitrogen as the key atom. Structurally amines resemble ammonia) and Carboxylic acids (organic acids characterized by the presence of a carboxyl group). Amino acids are used as the basic components of proteins.
The net protein utilization is profoundly affected by the limiting amino acid content or protein quality (the essential amino acid found in the smallest quantity in the foodstuff), and somewhat affected by salvage of essential amino acids in the body. It is therefore a good idea to mix foodstuffs that have different weaknesses in their essential amino acid distributions. This limits the loss of nitrogen through deamination and increases overall net protein utilization. Eggs (whether fish or even chicken) have the highest protein quality of any source. Which makes hard boiled egg crumbles an excellent food source for fry.
DL-methionine is an essential amino acid for producing the "Lionhead" feature in goldfish. High levels of methionine can be found in the vegetable proteins of spinach, green peas, and garlic. DL-methionine can also be found in fish meal.
Bottom line; Not all protein sources are equal. An analogy used at a pet food seminar I attended was this: You can achieve the protein analysis on many pet foods with a used pair of leather shoes, but leather shoes contain little usable proteins.
FATS:
Molecular compounds that are generally soluble in organic solvents and largely insoluble in water. Fats are important for insulating body organs against shock, maintaining body temperature, and promoting healthy cell function. They also serve as energy stores for the body. Fats are broken down in the body to release glycerol and free fatty acids. The glycerol can be converted to glucose by the liver and thus used as a source of energy. The fatty acids are the main source of energy in fish, especially for many tissues, such as heart and skeletal muscle. Another important function for fats are for vitamin absorption. Vitamins A, D, E, and K are fat-soluble, meaning they can only be digested, absorbed, and transported in conjunction with fats.
CARBOHYDRATES:
Molecular substances which include the sugars, starches, gums and celluloses. The common attributes of carbohydrates are that they contain only the elements carbon, hydrogen and oxygen, and that their combustion will yield carbon dioxide plus one or more molecules of Water. Most of the carbohydrates that enter the diet of fish are of plant origin. Carnivorous fish such as groupers, therefore, deal with little carbohydrate. Indeed, experiments have shown that these species are ill-equipped to handle significant quantities of raw carbohydrate, in their diets. The ability of fish to digest carbohydrates depends on their ability to elaborate amylase. All species of fish have been shown to secrete at least some amylase. It has also been demonstrated that activity of this enzyme was greatest in herbivores.
Carbohydrates are not a superior energy source for fish over protein or fat although digestible carbohydrates do spare protein for tissue building. Also, unlike in mammals, glycogen is not a significant storage depot of energy in fish. The more efficient metabolism of amino acids over carbohydrates (glucose) for energy could be due to the ability of fish to excrete nitrogenous waste as ammonia from their gills without the high cost of energy in converting the waste to urea.
FISH FOOD SOURCES:
FISH MEAL:
Fish meal has been widely used as a protein source for many years for fish. Two basic types of fish meal are produced; (1) produced from fishery waste (salmon, tuna, etc.) that are associated with the processing of various edible human fishery products and (2) When specific fish (herring, menhaden, pollack, etc.) are harvested just for the purpose to produce fish meal. The fish can be dried directly drying or cooking prior to drying and oil extracted. In addition to being a by-product of human fish production it is also a by-product associated with fish oil production, which is where most commercial fish food obtain fish meal from.
Fish meal can be classified as two basic types; (1) fishery waste associated with the processing of fish for human consumption, again the primary source. (2) Fish that are only used for the production of fish meal. This is the best source, listed on ingredients as "Whole Fish Meal" or "White Fish Meal".
SHRIMP MEAL:
Shrimp meal can be made from either cull shrimp that are being processed before freezing or from whole shrimp that is not of suitable quality for human consumption. The material to be made into shrimp meal is dried (sun or using a dryer) and then ground. Shrimp meal has been used in trout and salmon diets as a source of pigments to impart the desirable color in the tissues. Shrimp meal has been found to be an acceptable supplemental protein source for fish, but inferior to whole fish meal.
SQUID MEAL:
Squid Meal is made from squid viscera portions from cannery plants including egg and testis. Squid Meal is high digestibility of protein source, which provides a full range of amino acids for fish. It provides various kinds of vitamins and minerals and also 1.0-1.5% of cholesterol that is suitable for fish fry and young fish.
BRINE SHRIMP:
Just over a centimeter in size, the adult brine shrimp (Artemia) is a common food source for fish. They can be purchased at many Pet Store as adults, Freeze dried or even eggs. The eggs look like a powdery brown substance but in reality the substance is thousands of cysts—eggs surrounded by protective cases. When added to water, these cysts will hatch into shrimp nauplii within a few hours.
As a food source brine shrimp are relatively limited (mostly because of their high water content). They are a good source of carotene for color and act as a natural laxative in fish digestive systems. The proteins them do supply are of high quality. Depending on the source they also can supply vegetable matter due to their consumption of algae.
SOYBEAN MEAL:
Use of soybean products in the aquaculture industry have become the focus of protein substitution in fish food around the world. The high protein level makes it a key ingredient for aquaculture feeds. Soybean meal is considerably less expensive than traditionally used marine animal meals. The limiting amino acid content of soybean meal is high, but not on the level of Whole fish meal and especially egg.
SPIRULINA:
Spirulina is a blue-green plant plankton rich in raw protein and seven major vitamins: A1, B1, B2, B6, B12, C and E. It naturally contains beta-carotene, color enhancing pigments, and whole range of minerals. In addition, it contains all essential fatty acids and eight amino acids required for complete nutrition. Spirulina is different from other algae and is similar to bacteria in many ways, occupying a niche between plants and bacteria. Spirulina is similar to cyanobacteria in structure (spiral shape, unlike true plant plankton), which can be toxic. Spirulina Blue- Green algae are recognized by the body (fish in particular) as a bacterium, causing an increase in antibodies, which in turn increases disease resistance. Spirulina is also high in usable or digestible amino acids. Spirulina is probably one of the best fish food ingredients available, including for carnivores.
WHOLE WHEAT:
Carbohydrates as explained earlier are not the best source of energy in fish, but still can be useful, especially when whole wheat is used. One reason is for roughage, especially in goldfish and koi, but also for other fish for the wheat-germ found in whole wheat is a natural source of vitamin E, an important vitamin to promote healthy growth and fish color.
SUMMARY:
Compare TetraMin to some of the facts I have explained, then compare foods such as HBH Tropical and Marine Flake; Spirulina One Flake; Hikari and Sanyu Foods, such as Sanyu Betta Gold. The difference is quite clear for long term growth and health.
No comments:
Post a Comment