Ethoxyquin....
There is a lot of hype about ethoxyquin and its use in pet foods.... At this time, this is all anecdotal as unless fed in very high amounts it has not been shown to be toxic or carcenogenic (see
http://www.fda.gov/bbs/topics/ANSWERS/ANS00119.html for a short review of it (and see references at
http://ec.europa.eu/food/fs/sc/oldcomm6/other/10_en.pdf). Due to the fuss about ethoxyquin, many companies no longer use it as part of thier foods as a preservative which leads to a shorter shelflife for the foods due to increased oxidation of fat soluable vitamins. If foods that contain high levels of oxidized fat soluable vitamins are used then conditional nutritional deficiencies can result.
There are some broad nutritional guidelines for amphibians as dry matter on a
kcal basis the ratios should be as close to 50% protien, 44% fat and 6% carbohydrate. Most of the pelleted diets on the market as broken down on a % weight diet which is useless when evaluating the nutritional need of the amphibian as diets are figured out via kcals.
When looking at the nutrient list for the NLS, the biggest thing that flags up for me is the high levels of vitamin A as retinol compared to D3. This can over time cause problems with MBD as a conditional form if hypervitaminosis of A. The ratios of vitamin A (as retinol or retinol acetate) to D3 and E should be as close to 10:1:0.1 as possible otherwise conditional deficiences will eventually occur. When reviewing the levels of vitamin A in a product you need to determine if it is being supplied as a form of retinol or betacarotene (or other carotenoid like lutein) as only the retinol is toxic. Many foods list vitamin A on thier label but use beta carotene as the souce as it doesn't have the toxic issues that are a problem with retinol. Where an ingredient is listed in order of prevalence doesn't necessarily indicate how much is present. While the Rangen pellets list vitamin A in the middle of the list, this doesn't mean that it maybe as high as listed in the NLS formulation.
I have some concerns about the levels of vitamin A in the NLS formulation as they are at the top of the acceptable levels before toxicity occurs meaning that there is little leeway in the diet when using these.
Garlic really only has value as an antiparasitic if you are consuming whole cloves as once it has been cut the active compounds oxidize and have no real value anymore. This is hard to avoid in an extruded pellet...
Some comments,
Ed
I can go on a lot more about amphibian nutrition if anyone really wants to hear it....
Ed