Thiamin,

From Caresheets

Contents 1 THIAMIN, THIAMINASE, & GOLDFISH 2 SYMPTOMS OF THIAMIN DEFICIENCY 3 TREATMENT 4 B-COMPLEX VITAMINS 5 QUICK REFERENCE TO COMMON SAFE SPECIES OF FISH

[edit] THIAMIN, THIAMINASE, & GOLDFISH

Thiamin (AKA. Thiamine, both spellings are correct) is simply a newer name for Vitamin B1. It is a member of the B-complex vitamins (see below), and it, like all B-complex vitamins, is water soluble. This means they dissolve in water, aren't stored in the body long-term, and are eliminated via urates and feces. Therefore, they must be constantly replaced via the diet (or by symbiotic bacteria in the GI tract). In humans, thiamin stores can become depleted within 14 days if additional thiamin isn't consumed. Since snakes have much lower metabolic rates and they've evolved to conserve water, they excrete less often than humans, so their passage rate for thiamin is much slower. This suggests they may eliminate thaimin much slower, but actual values are elusive.

Thiamin's roles (The biology): Thiamin works at multiple places within energy conversion pathways (Glycolysis and the Citric Acid cycle), and it's a critical component of neural/muscular function. Without thiamin, pyruvate cannot be converted to Acetyl-CoA, so glycolytic pathways may be shut down or severely impaired (remember that the amount of thiaminase present controls how much or how little thiamin remains, see below). It has other roles in energy production that I'll gloss over. The key point, however, is that thiamin has critical roles in converting potential energy (in the form of food) into an energy source that the body can use to perform work (i.e. ATP). What might this mean if an organisms lacks sufficient thiamin supplies? See the "symptoms" section below.

Enzyme overview (The biology): Enzymes do work, but in order to do work, they require energy. The primary source of energy in animals is a molecule with a huge name that is commonly referred to as ATP. ATP is made by a very complex series of events that take place in a highly organized fashion. These processes convert the chemical energy stored in food into an energy source that the body can use (ATP). ATP is the primary cellular currency! Its importance to living organisms cannot be overstated. Anything that interferes with the ability to produce ATP is a major threat to living systems.

Thiaminase is the name for a family of enzymes that all cut a portion of the thiamin molecule away, leaving a non-functional vitamin behind. Since each thiaminase enzyme can destroy perhaps tens of thousands (or more) thiamin molecules during it's lifetime, very little thiaminase is required to have devastating impacts. Once destroyed, the body cannot restore thiamin. One study showed that a diet with as little as 10% thiaminase (metabolizable energy) required thiamin supplementation to keep the animal healthy. Therefore, a diet with less than 10% thiaminase-containing food sources might be considered safe, but the exact ratio is unknown. To be safe, it is best to completely avoid feeding foods, including goldfish, that contain the thiaminase enzyme, but offering a goldfish (on rare occasion) isn't harmful. Many of the effects of thiaminase deficiency aren't noticeable until they reach dangerous levels because they occur internally. Furthermore, snakes are known for their ability to hide ailments, so diagnosing a problem in its early stages is even more difficult.

Sources: Thiaminase enzymes can be found in a variety of plants, fish, and shellfish. The National Academy of Science conducted a literature review and compiled a list of fish that either contain or lack thiaminase enzymes (link below). It should be reviewed before establishing a diet for your snakes composed entirely of fish. Of note, goldfish are one of the most common food items recommended by pet stores for garters, yet they CONTAIN the thiaminase enzyme. A diet primarily composed of goldfish results in severe thiamin deficiency in 6-9 months. Without B1 supplements, a varied diet, or removal of additional thiaminase from the diet, death preceded by convulsions, will occur.

Wide-spectrum antibiotics can also destroy gastrointestinal bacteria that produce B-vitamins, so supplementing the diet may be useful.

Page 1 of NAS thiaminase table: http://books.nap.edu/books/030903325X/html/64.html#page_top

Page 2 of NAS thiaminase table: http://books.nap.edu/openbook.php?record_id=1114&page=65

[edit] SYMPTOMS OF THIAMIN DEFICIENCY

• Edema (swelling; can include swelling of the brain)
• Enlarged heart
• Abnormal heart arythmias (abnormal heartbeat pattern)
• Heart failure
• Weight loss and anorexia, despite hearty appetite and continued feeding
• Weakness
• Aching muscles / difficulty moving
• Lethargy
• Failure to respond to disturbance (walking by or opening the cage)
• "Star gazing" head becomes pulled back, giving the appearance of looking at stars
• Failure to reproduce
• Paralysis
• Convulsions / seizures
• Death

[edit] TREATMENT

• Garter snakes typically make a full recovery if the source of the thiaminase enzyme is removed from their diet, and the garters are placed on a proper diet (see general snake care caresheet).
• Vitamin B1 supplementation is effective in all but the most advanced stages of the condition because organisms use both active absorption (requiring ATP production, which is being impaired by the presence of thiaminase) and passive absorption (not sufficient to overcome digestive absorption problems).
• Advanced cases of thiamin deficiency require a veterinarian to inject thiamin directly into the snake. With treatment, snakes usually make a full recovery as long as the source of thiaminase is removed from their diet.

[edit] B-COMPLEX VITAMINS

• B1 (Thiamin) - An essential nutrient. Critical in energy production, carbohydrate metabolism, digestion, (formation of HCl in stomach), neural and muscular function.
• B2 (Riboflavin) - An essential nutrient. Critical part of energy production pathways and used in protein synthesis (growth, cellular repair, enzyme formation, etc.) and the break-down of fats.
• B3 (Niacin) - Component of enzymes, sex steroids, hormones, and neurotransmitter synthesis.
• B6 (Pyridoxine) - Mood enhancer, component of protein, hormone, and neurotransmitter synthesis.
• B12 (Cobalamin) - An essential nutrient. Used to treat anemia and maintains nerve cell integrity.
• Biotin - A gestational supplement.
• Pantothenic acid - Lowers stress.
• Folate (Folic acid) - Prevention of birth defects.

Further reading:

• • Sources include the National Institute of Health, University of Massachusetts, National Academy of Science, and various biochemistry textbooks. A better bibliography will be produced.

• Committee on Animal Nutrition, National Research Council. 1982. Nutrient Requirements of Mink and Foxes, Second Revised Edition. National Academy Press. Washington DC. USA.
• Stryker, Lubert. 1988. Biochemistry, 3rd Edition. W.H. Freeman and Company, New York, NY. USA.
• Voet, Donald and Voet Judith G. 1990. Biochemistry. John Wiley & Sons. New York, NY. USA.

[edit] QUICK REFERENCE TO COMMON SAFE SPECIES OF FISH

The following fish appear on the list linked above in this article. I have selected according to the following criteria... tested thiaminase free using whole body testing only, commercially available or available by angling, species with which I am familiar. So this is a PARTIAL list.

Bass (Largemouth), Bass (Smallmouth), Bluegill, Chub, Crappie, Herring, Mackerel, Pike (Northern), Pumpkinseed, Salmon (Coho), Trout (Brown), Trout (Rainbow), Whiting.

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