Analysis of foods
- Thread starter Deadliestviper7
- Start date
It's really difficult to say that one thing is a good diet for fish since the nutrition requirements of each species can differ greatly.
As mentioned, you don't want a lot of protein for goldfish, but you want much more for more carnivorous species. Tilapia can be raised completely on mixed plant protein, but this would be a huge issue for hydrolycus. Sturgeon can be fed diets without fish meal (experimental at this point) by having meat, bone, blood, and feather meal - but other fish cannot. They can also effectively use casein (found in mammalian milk) as a protein source. However, unlike many other species they cannot effectively utilize crystalline amino acids.
Also young fish require more protein than older fish. An adult sturgeon should eat around 45% protein but a juvenile needs over 50%. Younger fish need to grow more muscle and viscera than older fish.
And then you have freshwater vs. saltwater. Freshwater fish have fewer requirements for amino acids as they can desaturate and elongate a few certain essential amino acids to create others. Saltwater fish cannot, so they need to obtain them from the diet. It's always better to feed saltwater diets to freshwater fish than the other way around.
To summarize, it is too difficult to analyze a given diet for all fish. If we can talk about one species or taxon of fish then we can get somewhere!
As mentioned, you don't want a lot of protein for goldfish, but you want much more for more carnivorous species. Tilapia can be raised completely on mixed plant protein, but this would be a huge issue for hydrolycus. Sturgeon can be fed diets without fish meal (experimental at this point) by having meat, bone, blood, and feather meal - but other fish cannot. They can also effectively use casein (found in mammalian milk) as a protein source. However, unlike many other species they cannot effectively utilize crystalline amino acids.
Also young fish require more protein than older fish. An adult sturgeon should eat around 45% protein but a juvenile needs over 50%. Younger fish need to grow more muscle and viscera than older fish.
And then you have freshwater vs. saltwater. Freshwater fish have fewer requirements for amino acids as they can desaturate and elongate a few certain essential amino acids to create others. Saltwater fish cannot, so they need to obtain them from the diet. It's always better to feed saltwater diets to freshwater fish than the other way around.
To summarize, it is too difficult to analyze a given diet for all fish. If we can talk about one species or taxon of fish then we can get somewhere!
Also I forgot to mention that "protein" doesn't necessarily mean much. It's just your total amino acids. That means that in theory you could have lots of protein but a given species may not be able to digest much of it at all! Really what you want to know is the amino acid content. The same goes for fats and fatty acids. Unfortunately most brands don't give you this info which is one of the reasons why we as a community are always trying to find the best diet!
So far I agree with all being said, but I still see a lot of bad diets for fish by so called experts, and calling this an analysis may be taking it to far i agree couldn't think of a better word
