Date: 2011-05-25 19:15:33 UTC
Subject: [ferrethealth] Re: Why Do Ferrets Need Taurine?
I think that eHOW might have really messed up...
So far it looks like the the resource given at the start of this conversation does not appear to have basis in relation to ferrets for many of the statements made, so it might be more of a "resource" than an actual resource, but those whose college degrees them more background than mine could really help by chiming in about what is known in relation to ferrets and taurine, and what is postulated with good cause to wonder and at some time study vs statements that appear to lack even a possible foundation. Too bad that website did not include a reading list.
Ferret foods created by people with doctorates in veterinary nutrition DO include taurine.
Working first from PubMed
Not all refs will be useful for most people.
Betacarotene related taurine studies often were used as part of a complex of studies that used ferrets as models for damage from cigarettes. They were the primary animal used to look at how betacartene behaves differently when damage already exists, and some of the related studies showed that ferrets who are exposed to tobacco smoke can get lung tumors just like people do. Basically, a lot of ferrets died showing that humans who already have damage from tobacco are probably not protected by betacartene and some might worsen a bit with it as a supplement; that is what happened with the ferrets ultimately.
Int J Vitam Nutr Res. 2005 Mar;75(2):133-41.
Effects of dietary taurocholate, fat and protein on the storage and metabolism of dietary beta-carotene and alpha-tocopherol in ferrets.
Sundaresan PR, Marmillot P, Liu QH, Mitchell GV, Grundel E, Lakshman MR.
Division of Research and Applied Technology, Office of Nutritional Products, Labeling and Dietary Supplements, Center for Food Safety & Applied Nutrition, Food and Drug Administration, Washington, DC 20204, USA.
Dietary factors affecting tissue storage of beta-carotene (BC), alpha-tocopherol (alpha-T), and retinol (ROL) in mammals include taurocholate, protein, and fat. Few studies have examined the effects of these factors on the storage of BC, retinyl esters, and alpha-T in a mammalian system that is similar to humans. The main objective of the study was to investigate the effects of taurocholate (TC), fat, and protein on the absorption and metabolism of BC and alpha-T in ferret tissues. Three 4-week experiments were conducted using groups of 5-6 ferrets per treatment. All diets contained 0.2% BC. In Experiment 1, taurocholate was fed at concentrations of 0, 0.5, or 1%. Effects of two concentrations of dietary fat (6 and 23%) and three concentrations of protein (10, 20, and 40%) were also studied in Experiments 2 and 3, respectively. Tissues were analyzed for BC, retinoids, and alpha-T by high-pressure liquid chromatography (HPLC). Taurocholate enhanced hepatic and plasma concentrations of BC (2.3- to 3-fold), retinyl palmitate [(RP) 3.2- to 9.5-fold], retinyl stearate [(RS) 2.9- to 6- fold], and hepatic alpha-T (6- to 13- fold) at p < 0.05. High-fat diets elevated hepatic BC, RP, RS, and retinyl linoleate (RL) concentrations (2- to 3.6-fold, p < 0.05). In contrast, high-protein diets lowered hepatic RL 1.8-fold and alpha-T 8-fold (p < 0.05). Our results indicate the importance of taurocholate, fat, and protein in achieving adequate levels of vitamins A and E in mammals.
PMID: 15929634 [PubMed - indexed for MEDLINE]
Nutr Cancer. 1998;31(1):18-23.
Taurocholate stimulates the absorption and biotransformation of beta-carotene in intact and lymph duct-cannulated ferrets.
Marmillot P, Satchithanandam S, Liu QH, Lakshman MR.
Department of Medicine, George Washington University, Washington, DC 20037, USA.
We have determined the influence of dietary taurocholate and beta-carotene on the absorption and biotransformation of newly administered beta-14C]carotene. Male ferrets were fed the control or beta-carotene diet (0.05% beta carotene wt/wt) with and without taurocholate (1% wt/wt) for four weeks, and then the absorption and biotransformation of newly administered beta-[14C]carotene was measured after eight hours in intact or thoracic lymph duct-cannulated animals. Percent recover of beta-[14C]carotene in the liver was increased 3.6-fold (p < 0.05) in the taurocholate-fed ferrets regardless of whether they were fed the control or beta-carotene diet. Percent recovery of labeled vitamin A in the liver was also increased by the same magnitude (p < 0.05). These results were confirmed in thoracic lymph duct-cannulated ferrets. The recoveries of beta-carotene label in the lymph were comparable to the corresponding values in livers of intact animals. The recovery of beta-carotene label in the liver was 50% (p M 0.05) higher in beta-carotene-fed than in control animals. Taurocholate stimulates intestinal absorption of newly administered beta [14C]carotene and its metabolic conversion to 14C-labeled vitamin A (retinol + retinyl ester) 3.6-fold. Beta-Carotene absorption is as efficient in thoracic lymph duct-cannulated ferrets as in intact animals. Prior beta-carotene feeding also stimulates the absorption of newly administered beta-carotene by 50%.
PMID: 9682244 [PubMed - indexed for MEDLINE]
Nutr Cancer. 1996;26(1):49-61.
The effects of dietary taurocholate, fat, protein, and carbohydrate on the distribution and fate of dietary beta-carotene in ferrets.
Lakshman MR, Liu QH, Sapp R, Somanchi M, Sundaresan PR.
Lipid Research Laboratory, Department of Veterans Affairs Medical Center, Washington, DC 20422, USA.
Dietary beta-carotene has been shown to have cancer chemopreventive action on the basis of epidemiologic evidence and studies in animals. Because the anticarcinogenic property of beta-carotene may be exerted per se, it is desirable to achieve the maximum absorption and accumulation of intact beta-carotene in various parts of the body. Therefore the effects of dietary taurocholate, fat, protein, and carbohydrate on the absorption, accumulation, and fate of dietary beta-carotene (3.730 nmol/g diet) in selected tissues of ferrets were explored. Taurocholate (0.2-1.0% wt/wt) and fat (6-23% wt/wt) caused two- to threefold (p < 0.05) increases in the absorption and accumulation of beta-carotene in the liver, lungs, and adipose tissue in a dose-dependent manner. In contrast, neither dietary protein (10-40% wt/wt) nor carbohydrate (25-55% wt/wt) affected the absorption and accumulation of beta-carotene in various tissues. Significantly, taurocholate, 23% fat, or 40% protein also markedly increased the amounts of hepatic retinol and retinyl esters derived from dietary beta-carotene. These results indicate that dietary taurocholate, fat, and high protein have a marked influence on the exposure of beta-carotene to intestinal carotene cleavage enzyme or its activity. Thus an ideal combination of dietary components (wt/wt) in ferrets for the maximal absorption and accumulation of beta-carotene in different tissues is 0.5% taurocholate and 13.4% fat, whereas 1% taurocholate, 23% fat, or 40% protein stimulates its conversion to vitamin A.
PMID: 8844721 [PubMed - indexed for MEDLINE]
1. Prog Clin Biol Res. 1990;351:397-405.
Taurine function in the auditory system.
Davies WE, Kay IS, Birnso OV.
Department of Pharmacology, Medical School, University of Birmingham, U.K.
PMID: 2122479 [PubMed - indexed for MEDLINE]
Xenobiotica. 1983 Mar;13(3):133-8.
The utilization of exogenous taurine for the conjugation of xenobiotic acids in the ferret.
Emudianughe TS, Caldwell J, Smith RL.
Although the occurrence of the taurine conjugation mechanism for various xenobiotic acids is well established, nothing is known of the source of the taurine used for this conjugation. [14C]Taurine was administered alone and in combination with 2-naphthylacetic acid or clofibric acid (both of which are known to form taurine conjugates) to to ferrets, and the 0--24 h urine collected. Of the dose of [14C]taurine, 26% was recovered in the urine in 24 h and the only 14C-containing material present was unchanged taurine. When either 2-naphthylacetic acid or clofibric acid was co-administered with [14C]taurine, 21 and 17%, respectively, of the 14C dose was recovered in the 0--24 h urine. In both cases, two 14C compounds were present--unchanged taurine (minor) and the taurine conjugate of the acid in question (major). Comparison of these results with those previously obtained with 14C-labelled 2-naphthylacetic and clofibric acids, shows that the taurine used for their conjugation is derived from a pool freely accessible to exogenous taurine. The results are discussed in terms of the availability for metabolic utilization of taurine in the animal body, and of the use of co-administration of [14C]taurine with a xenobiotic acid for the identification of taurine conjugates.
PMID: 6613158 [PubMed - indexed for MEDLINE]
Drug Metab Dispos. 1983 Mar-Apr;11(2):97-102.
Species differences in the metabolic conjugation of clofibric acid and clofibrate in laboratory animals and man.
Emudianughe TS, Caldwell J, Sinclair KA, Smith RL.
The urinary metabolites of single doses of clofibric acid (p-chlorophenoxyisobutyric acid), and its ethyl ester, clofibrate, have been investigated in rat, guinea pig, rabbit, dog, cat, ferret, and human volunteers. Human volunteers, rodents, and rabbits given clofibric acid excreted 60-90% of the 14C dose in the urine in 24 hr, and the only metabolite found was the ester glucuronide of clofibric acid, together with small amounts of the unchanged acid. In the dog, cat, and ferret, however, urinary excretion of 14C was much slower (23-39% of dose in 24 hr) and these species all formed the taurine conjugate of clofibric acid, excreted together with the unchanged acid. The ester glucuronide was found in the urine of dog and ferret but not cat. The fate of clofibrate, the ethyl ester of clofibric acid, in rat, guinea pig, rabbit, and man was similar to that of the parent acid. The characterization of the glucuronic acid and taurine conjugates of clofibric acid is described.
PMID: 6133730 [PubMed - indexed for MEDLINE]
Drug Metab Dispos. 1981 Jul-Aug;9(4):352-9.
Species differences in the metabolism of 3-phenoxybenzoic acid.
Huckle KR, Hutson DH, Millburn P.
The metabolism of 3-phenoxybenzoic acid (3PBA) (10 mg/kg, ip) has been studied in ten mammalian and one avian species in comparison with that of benzoic acid. 3PBA exhibits wide species diversity in its metabolism, unlike benzoic acid, of which benzoylglycine (hippuric acid) is the major urinary metabolite in all species studied. With 3PBA, glycine conjugation is the major route of metabolism in three species (sheep, cat, and gerbil), whereas in the mouse the taurine conjugate is the principal metabolite. The ferret eliminates similar amounts of each of these metabolites, whereas the glycylvaline dipeptide conjugate is the major metabolite isolated from the excreta of the mallard duck. Conversely, glucuronic acid conjugates of 3PBA and its 4'-hydroxy derivative (4'HO3PBA) are the major urinary metabolites in the marmoset, rabbit, guinea pig, and hamster; the rat appears unique in eliminating the O-sulfate conjugate of 4'HO3PBA as the principal urinary metabolite. In most cases, where amino acid conjugates are the major excretory products, the proportions of hydroxylated metabolites present are minimal. The pattern of metabolism of 3PBA does not significantly vary with dose (0.1-100 mg/kg) or route (ip and po) in the sheep, gerbil, or mouse. When administered 4'HO3PBA, the gerbil and mouse eliminate principally glucuronide and sulfate conjugates rather than amino acid conjugates, which are only minor components (less than 10% of the dose) in each case. This implies that hydroxylation is a primary metabolic event in determining the eventual fate of 3PBA in many species.
PMID: 6114835 [PubMed - indexed for MEDLINE]
Br J Pharmacol. 1979 Jul;66(3):421P-422P.
Species variation in the taurine conjugation of clofibric acid [proceedings].
Caldwell J, Emudianughe TS, Smith RL.
PMID: 526711 [PubMed - indexed for MEDLINE] PMCID: PMC2043729 Free PMC Article
Xenobiotica. 1978 Apr;8(4):253-64.
Taurine conjugates as metabolites of arylacetic acids in the ferret.
Idle JR, Millburn P, Williams RT.
1. The pattern of conjugation in the ferret of 8 arylacetic acids and, for comparison, benzoic acid and 4-nitrobenzoic acid was examined. 2. The arylacetic acids, phenylacetic, 4-chloro- and 4-nitro phenylacetic, alpha-methylphenylacetic (hydratropic), 1- and 2-naphthylacetic and indol-3-ylacetic acids, were excreted in the urine as taurine and glycine conjugates. Diphenylacetic acid did not form an amino acid conjugate and was excreted as a glucuronide. 3. The taurine conjugate was the major metabolite of 4-nitrophenylacetic, alpha-methylphenylacetic, 1- and 2-naphthylacetic and indol-3-ylacetic acids, whereas the glycine conjugate was the major metabolite of phenylacetic and 4-chlorophenylacetic acids. Taurine conjugation did not occur with benzoic and 4-nitrobenzoic acids which were excreted as glycine and glucuronic acid conjugates. 4. Phenacetylglutamine and 4-hydroxyphenylacetic acid were minor urinary metabolites of phenylacetic in the ferret. 5. A number of taurine conjugates of aliphatic and aromatic acids were synthesized and their characterization and properties were studied. The role of taurine as an alternative to glycine in the metabolic conjugation of arylacetic acids is discussed.
PMID: 347725 [PubMed - indexed for MEDLINE]
Biochem Soc Trans. 1977;5(4):1033-5.
Glutamine conjugation of phenylacetic acid in the ferret [proceedings].
Hirom PC, Idle JR, Millburn P, Williams RT.
PMID: 913772 [PubMed - indexed for MEDLINE]
Biochem Soc Trans. 1977;5(4):1006-8.
Structure-metabolism relationship of arylacetic acids: the metabolic fate of naphth-2ylacetic acid in vivo.
Emudianughe TS, Caldwell J, Smith RL.
PMID: 913763 [PubMed - indexed for MEDLINE]
Biochem Soc Trans. 1976;4(1):139-41.
Taurine conjugation of arylacetic acids in the ferret.
Idle JR, Millburn P, Williams RT.
PMID: 1001620 [PubMed - indexed for MEDLINE]
After that I used Google Scholar
but I will need to look to see if they have a compilation after 2006
though they may not or I might not succeed in finding it. There are two
earlier compilations, BTW.
I do not see any more recent references in there.
Note that there is a dearth of recent studies. The lack of recent studies might indicate that the little bit that is actually known on this topic is the same as it's been for years and years: The low taurine intake appears to be related to some cataracts and might be related to some heart disease in ferrets. It is also possible that the author at that website might, for at least some of the claims, be going from work in other species and in that case the refs (not listed) even more strongly needed to be given because assuming from another species is not always a sound practice. I think that the person may be working from cat (not ferret) studies in part, such as:
and from resources like
Taurine deficiencies have been studied in the cat but are not described in the ferret. However, as dilated cardiomyopathy has been reported in the ferret (8), and some interest in the role of taurine has been generated. However, although feline cardiomyopathies may sometimes respond to taurine supplementation, this effect has not been seen in the ferret (8). Taurine is generally present in premium ferret rations although it is not usually listed...
and note that does give a reference number for the bibliography to:
Stamoulis ME, Miller MS, Hillyer EV: Cardiovascular diseases, in Hillyer EV, Quesenberry KE (eds): Ferrets, Rabbits, and Rodents. Philadelphia, PA, Saunders, 1997, pp 63-76
is page 307 but the search seems to reflect page 317 of that section on cardiomyopathy in _Biology and Diseases of the Ferret_ (Chapter 13, "Other Systemic Diseases") by James Fox.
There could well be some general mammal and general animal things about taurine that can be applied to the ferret, but with no bibliography given, no qualifications given for the author of that website article, and no corroborating references being found it is pretty hard to take that resource at face value, for me personally it is pretty well impossible to do so.
Sukie (not a vet)
Recommended ferret health links:
all ferret topics:
"All hail the procrastinators for they shall rule the world tomorrow."
(2010, Steve Crandall)
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