30 



THIAMINE DEPLETION DIET: / 



A - NO SUPPLEMENT / 



8 - PLUS 1/2 OM./OAY STARFISH^/ 

 C - PLUS I GM./OAY STARFISH 

 D - PLUS 1-1/2 OM./DAT 



STARFISH 

 E - PLUS 20 MICROGHS. 



PER 100 SMS. DIET/ 



Considerable difficulty was experienced in getting the rats to eat the star- 

 fish supplements, the material apparently was quite unpalatable. This was par- 

 ticularly true of those rats with unlimited 

 access to the stock diet. A number of the 

 animals receiving depletion diets also refused 

 to eat part or all of the starfish offered. 

 This was notably so for those few rats in these 

 groups which gained weight during the test 

 period. 



On the basis of these tests , it was evident 

 that there was present in starfish a substance 

 capable of destroying a limited amount of thi- 

 amine* These studies had been started in Novem- 

 ber 1941, at which time "anti-thiamine," as 

 it was then called , had been reported but very s 

 little was known regarding its chemical struc- S 

 ture or mode of action. Chemical assay methods 

 had not been developed, so that it was necessary = 

 to use the biological assay method for thi- j 

 amine. By the use of two series of test groups = 

 supplemented with thiamine, one with and the 

 other without an additional supplement of raw 

 starfish, it "should have been possible to de- 

 termine the thiamine destroyed per gram of 

 starfish. 



This method did not succeed because of the 

 refusal of most of the rats to eat the star- 

 fish supplement with sufficient regularity to 

 permit any degree of quantitative comparison. 

 The basal depletion diet was fed alone and 

 with 10, 30, and 60 micrograms of thiamine 

 per 100 grams, with U other groups being fed 

 the same diets plus 1 gram per day of raw star- 

 fish. During the shortened test period, each of the groups fed starfish gained 

 less weight than the corresponding groups without starfish but the data showed no 

 significant correlations. 



3 4 



WEEKS 

 FIGURE I - GROWTH CURVES FOR RATS FED 

 THIAMINE BASAL TEST DIET ALONE, AND 

 WITH SEPARATE DAILY SUPPLEMENTS OF 

 RAW GROUND STARFISH AS INOICATED. 



A third series of rats was used to determine the practicability of mixing the 

 ground starfish directly into the basal diet, also to ascertain the reported heat 

 lability of thiaminase. Four groups of 6 rats each were used; these were fed the 

 basal thiamine test diet alone; with 10 percent raw starfish; with 10 percent of 

 starfish which had previously been autoclaved for 15 minutes at 15 pounds pressure; 

 and with an amount of starfish oil equal to that which would be introduced by 

 the inclusion of 10 percent starfish in the diet. 



Of course, with finely ground starfish mixed into the diet, the only alterna- 

 tive to eating the mixture was fasting. The amount eaten varied depending upon 

 the condition of the rats . It is probable that the starfish produced a depressing 

 effect upon the appetite, in addition to and before the onset of the anorexia 

 resulting from the thiamine deficiency due to the action of the thiaminase. 



The control rats in this group gained an average of 5.8 grams per rat per week 

 during the test period; whereas, those fed raw starfish lost 2 to 34 grams, the 



