OKLAHOMA ACADEMY OF SCIENCE 69 



changing to a violet, then black, the changes being due to oxidation. 

 Experimental Work with Gossypol 



Ether will extract the gossypol from cottonseed meal, the ex- 

 tracted meal is not toxic to rabbits; the ether extract after the re- 

 moval of the ether is toxic and consists of crude gossj^pol. One- 

 tenth of a gram of gossypol fed to rabbits each day with thoir 

 ration, results in their death, in from eight to twenty-five days, even 

 if the gossypol is put in their ration for only three or four day-. 

 In some cases a rabbit which had been given only one-tenth of a 

 gram died fourteen days afterwards. One-tenth of a gram given in 

 a single dose seems to be the smallest amount that will cause death 

 in a rabbit. A peculiar feature about the effects of gossypol or 

 cottonseed, is that the animals may eat these substances for several 

 days without seeming affected, then they may suddenly cease 

 eating, waste away and finally die. 



Five-hundreths of a gram of gossypol injected into the blood 

 vessel of a rabbit caused death in about four minutes. The animal 

 acted as though suffocated, leaped high in the air and gasping 

 during this interval. On post mortem examination, the blood was 

 found to be black in color as though death was due to suffocation. 

 One-half this amount was given in the same m,anner, the' animal 

 l)ecame aparently paralyzed, and lay on the floor, unable to move its 

 limbs. The animal recovered the use of its limbs after an hour 

 and sat up. but died sixteen hours later. 



These experiments indicate that gossypol affects the oxygen 

 carrying power of b:ood, so experiments to determinte the oxygen 

 carrying power of blod treated with gossypol were made. Sheep's 

 blood saturated with oxygen, arterial was used, and the "oxygen 

 capacity" i. e., the amount of oxygen that a definite volume of blood 

 would liberate was determined. Two hundredths of a gram of 

 gossypol in two c. c. of blood, i. e., with 1% gossypol, the blood 

 gave off only 45.6%- of the oxygen that the same amount of blood 

 without the gossypol, would liberate. Two thousandths of a gram 

 of gossypol added to two c. c. of blood i. e., with A'/c gossypol, the 

 l)lood gave off only 64% of the oxygen liberated by the arterial blood. 



Venous blood v/ill liljerate 75% of the amount of oxygen that 

 arterial Ijlood will liberate. It is evident that gossypol prevents the 

 liberation of oxygen from the blood, and this property is very 

 marked even when very small quantities of gossypol are present, — 

 one-ttnth of one per cent of gossypol. 



These results are in accordance with the symptoms observed 

 after feeding cottonseed to animals, noticeably, a shortness of 

 breath. 



