33 



separate evaluation of the two effects is impossible from the present data. It 

 is evident, however, that the mortality was primarily the result of a thiamine 

 deficiency due to the thiaminase content of the starfish meal rather than to ex- 

 cess calcium. 



Raw starfish, Asterias 

 monly called "thiaminase 



I DIET WITH 8* STAflFISH 

 I DIET u TM 32* 

 ► I CT WITH 29.5* SOLV. EXTD. 

 STARFISH 

 CHICK DIED DURING TEST 

 INDICATES ADDITION OF 1 00 

 MICROGMS. OF THIAMINE PER 

 100 OHS. OF OIET 



CONCLUSIONS 



forbesi , contains a thiamine-destructive enzyme, cora- 

 This was demonstrated by the development of polyneuritis 

 in rats fed one or more grams of raw star- 

 fish per day. Recovery and normal growth 

 resulted from the addition of an adequate 

 level of thiamine to the diet. 



J I I L_L 



It was difficult to 

 titative estimate of the 

 amine destroyed because 

 of rats to eat the 

 regularity. The 



I 8 



WEEKS 

 FIGURE 4 - GROWTH CURVES FOR NEWLT HATCHED CHICKS, FED 

 EQUI-PROTEIN MASHES CONTAINING 8 PERCENT STARFISH MEAL 

 SHOWING NORMAL GROWTH. ALSO CURVES FOR CHICKS FED 32 

 PERCENT STARFISH MEAL DRIEO AT A LOW TEMPERATURE, AND 

 29.5 PERCENT OF SAME MEAL WITH LIPOIDS EXTRACTED BY 

 ACETONE. THE LATTER TWO OIETS WERE SUPPLEMENTED BY 

 100 MICROGRAMS TKIAM1NE PER 1 00 GRAMS OF OIET AFTER 3 

 WEEKS, AND THE 32 PERCENT STARFISH MEAL MASH HAD THE 

 SUPPLEMENT OF THIAMINE INCREASED TO 200 MICROGRAMS OF 

 THIAMINE AFTER 37 DAYS, AS INOICATEO BY ARROWS. 



obtain a quan- 

 amount of thi- 

 of the refusal 

 raw starfish with any 

 best estimate is that 

 one gram of starfish inactivates four 

 micrograms of thiamine. There are in- 

 dications that other samples of starfish 

 may contain greater amounts of thiaminase . 



The thiaminase in starfish is suf- 

 ficiently stable to remain in starfish 

 meal that has been sun-dried or dried 

 at low temperatures. There are no data 

 to show the amount of thiaminase lost 

 under different conditions of drying. 



Thiaminase in starfish meal is pri- 

 marily responsible for mortality of chicks 

 fed diets containing high levels of this 

 product. This factor and the high calcium 

 content of the starfish meal are respon- 

 sible for the poor growth obtained . Evi- 

 dence from other sources indicates that 

 thiaminase would be destroyed at the tem- 

 peratures commonly used in the dryers 

 in the commercial production of protein 

 meals from fishery products. Any small 

 amount of thiaminase remaining would not 

 give much response since usually less 

 than 10 percent of mixed animal protein 

 supplements are included in commercial 

 mash formulas . 



LITERATURE CITED 



BHAGVAT, K. and IEVI , P. 



1944. Inactivation of thiamine by certain foodstuffs and oilseeds. Parts I and II, 

 Indian Jour. Med. Res. , 32: 131-44. 



HUTCHINSON, G. E. , SETLOW, J. K. , and BROOKS, J. L. 



1546. Biochemical observations on Asterias forbesi , Bingham Oceanographic Coll. Bull., 

 9, Art. 3: 3-6. 



