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DEPARTMENT OF AGRICULTURE 



Vol. V Washington, D. C, November 15, 1915 No. 7 



GOSSYPOL, THE TOXIC SUBSTANCE IN COTTONSEED 

 MEAL.^ 



By W. A. Withers and F. E. Carruth,^ 

 North Carolina Agricultural Experiment Station 



TOXICITY OF COTTONSEED 



The term "cottonseed meal" is applied to the ground cake left after 

 the oil is pressed from the seed of cotton (Gossypium spp.). For many 

 years it was regarded as a by-product of little value. It is now used 

 extensively as a feed. The annual production of the United States is 

 about 2,000,000 tons, valued at about $53,000,000. While it may be 

 fed profitably to horses, cattle, sheep, etc., in moderate amounts, poison- 

 ing and often death occur as a result, especially if the animal has not 

 been gradually accustomed to it. It is generally avoided as a feed for 

 pigs on account of the numerous deaths associated with its use, Din- 

 widdle (1905) states that hogs show no greater susceptibility than cattle 

 when fed quantities proportional to their body weight. Feeding experi- 

 ments at the North Carolina Experiment Station have shown that where 

 swine are fed one part of cottonseed meal with three parts of com meal 

 death generally ensues in from five to seven weeks, although some pigs 

 have been fed for a year or more without fatal results. 



In a recent experiment at this Station nine pigs weighing from 75 to 

 150 pounds were fed in a closed pen on a daily ration of i per cent of 

 cottonseed meal and 3 per cent of com meal, based on their initial body 

 weight. Six died between the thirty-fifth and the fifty-seventh day. 

 The others were alive on the ninetieth day. Roughly, then, 45 per cent 

 of their initial weight in cottonseed meal was fatal to these pigs. All the 

 smaller pigs died. 



Withers and Brewster (191 3) found that rabbits and guinea pigs would 

 succumb in about 13 days (6 to 22 days) when fed at the rate of i per cent 

 of initial body weight daily. Experiments with 22 rabbits showed that, on 



1 This paper is the third in a series of " Studies in Cottonseed Meal Toxicity. ' ' Study I, Withers and Ray 

 (1913), is a criticism of Crawford's pyrophosphoric-acid hypothesis; Study II, Withers and Brewster (1913), 

 suggests iron salts as an antidote. 



- For their cooperation with us in this investigation, we desire to thank Dr. G. A. Roberts and Dr. 

 W. B. Smith, of the Veterinary Department, and Dr. B. F. Kaupp, Pathologist, of the Poultry Depart- 

 ment, North Carolina Experiment Station. 



Journal of Agricultural Research, Vol. V, No. 7 



Dept. of Agriculture, Washington, D. C. Nov. 15, 1915 



ao N. C— I 



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