JOURNAL OF AGRMLTIIRAL RESEARCH 
DEPARTMENT OF AGRICULTURE 
Von. V Washington, D. C., November 15, 1915 No. 7 
GOSSYPOL, THE TOXIC SUBSTANCE IN COTTONSEED 
MEAL . 1 
By W. A. Withers and F. E. Carruth , 2 
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- 
widdie (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 corn 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 1 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 (1913) found that rabbits and guinea pigs would 
succumb in about 13 days (6 to 22 days) when fed at the rate of 1 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 (19x3), 
suggests iron salts as an antidote. 
2 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. 
Vol. V, No. 7 
Nov. 15,191 s 
N. C.—1 
Journal of Agricultural Research, 
Dept, of Agriculture, Washington, D. C. 
(261) 
