OAK-LEAF POISONING OF DOMESTIC ANIMALS. 7 
occur in the spring. Some say that all cases are in the spring. 
Most observers say that the harmful effects are produced by eating 
the buds and young leaves. Some say that these are most harmful 
after being frosted. It has been noted by many that cattle in poor 
condition in the spring of the year are most liable to be affected, 
and that if well fed they are not harmed. 
Symptoms. — The symptoms described by Cornevin included loss 
of appetite, cessation of rumination and lactation, fever, trembling 
of muscles, dark-red urine, and constipation followed by dysentery; 
the autopsies showed gastroenteritis and acute nephritis. 
The reports from supposed oak-brush poisoning in the United 
States do not agree very closely with Cornevin's description. Barnes, 
1913, gives the prominent symptoms as fever, scabby sore nose, 
deep-set eyes, hair turned the wrong way, difficult breathing, and 
contents of stomach compacted, the material being dry and burned. 
From the reports of different stockmen may be added as charac- 
teristic symptoms, constipation, dark or bloody feces, and emacia- 
tion ; it is said by some that an examination of the stomach contents 
shows masses of oak leaves, and that the material in the third stomach 
is dry and hard. Some of the cases are said to be acute but many 
linger along for weeks and months. 
Animals poisoned. — The principal complaint is of cattle, although 
sheep have been reported as affected by oak. It may be noted that 
the European authors, Cornevin more particularly, apparently con- 
sider cattle the principal sufferers, though sheep and deer are men- 
tioned. Harting says that goats are not injured. 
EXPERIMENTAL WORK WITH SCRUB OAK. 
A considerable number of so-called oak-brush cases have been 
seen upon the range in Utah and Texas. These animals exhibit the 
common symptoms of emaciation, sunken eyes, weakness, and 
bloody feces. Autopsies have shown a gastroenteritis and some- 
times a pathological condition, of the liver which might be explained 
by parasitism. The temperature in observed cases was subnormal 
rather than one indicating fever. The general condition of the 
animals closely resembled that exhibited by locoed animals. This 
condition in Utah is known as "summer sickness" as well as "oak- 
brush poisoning. " 
During four summers, 1915, 1916, 1917, and 1918, feeding experi- 
ments were conducted with cattle at the Salina experiment station, 
Utah, to determine whether feeding upon oak leaves is harmful. All 
these experiments were with the scrub oak of Utah, Quercus gambellii. 
The table following gives a summarized statement of the feeding 
experiments : 
