General poisoning notes:

Red oak (Quercus rubra) is a native tree found in eastern Canada. This plant contains toxic tannins that have caused poisoning and death in cattle and horses. Sheep may have also been poisoned by this oak. Poisoning can lead to depression, anorexia, loss of condition, and kidney damage. Kidney failure usually results in death (Duncan 1961, Cockerill and Beasley 1979).

References:

Cockrill, J. M., Beasley, J. N. 1979. Renal damage to cattle during acorn poisoning. Vet. Med. Small Anim. Clin., 74: 82, 84-85.

Duncan, C. S. 1961. Oak leaf poisoning in two horses. Cornell Vet., 51: 159-162.

Nomenclature:

Scientific Name: Quercus rubra L.

Vernacular name(s): red oak

Scientific family name: Fagaceae

Vernacular family name: beech

Go to ITIS*^ca for more taxonomic information on: Quercus rubra

References:

Agriculture Quebec. 1975. Noms des maladies des plantes du Canada/ Names of plant diseases in Canada. , Quebec City, Que., Canada. 288 pp.

Alex, J. F., Cayouette, R., Mulligan, G. A. 1980. Common and botanical names of weeds in Canada/Noms populaire et scientifiques des plantes nuisibles du Canada. Revised. Agric. Can. Publ., Ottawa, Ont., Canada. 132 pp.

Bailey, L. H., Bailey, E. Z. 1976. Hortus third. Revised. MacMillan, New York, N.Y., USA. 1290 pp.

Scoggan, H. J. 1978, 1979. The flora of Canada. Nat. Mus. Nat. Sci. (Ottawa) Publ. Bot. 7(1)-7(4). 1711 pp.

Van Wijk, H. L. 1911. A dictionary of plant names. Martinus Nijhoff, The Hague, The Netherlands. 1444 pp.

Victorin, M. 1964. Flore Laurentienne. 2nd ed. Univ. Montreal, Montreal, Que., Canada. 952 pp.

Geographic Information

New Brunswick
Nova Scotia
Ontario
Prince Edward Island
Quebec

References:

Bailey, L. H., Bailey, E. Z. 1976. Hortus third. Revised. MacMillan, New York, N.Y., USA. 1290 pp.

Boivin, B. 1966, 1967. Énumération des plantes du Canada. Provencheria 6. Nat. Can. (Que.) 93: 253-274; 371-437; 583-646; 989-1063. 94: 131-157; 471-528; 625-655.

Image or illustration

red oak:

Images: images.google.com

Notes on Poisonous plant parts:

The leaves and acorns are toxic. The immature acorns contain more toxin than the mature acorns (Cockrill and Beasley 1979).

Toxic parts:

acorns
immature fruit
leaves

References:

Cockrill, J. M., Beasley, J. N. 1979. Renal damage to cattle during acorn poisoning. Vet. Med. Small Anim. Clin., 74: 82, 84-85.

Notes on Toxic plant chemicals:

The toxic agents are polyhydroxyphenolic compounds (tannins) including gallic acid, pyrogallol, and tannic acid. The concentration of these compounds is higher in immature, green acorns than in mature ones. The following quantities of phenolics were found in acorns (Basden and Dalvi 1987):

Oak species	Total phenolics (% of total weight)
Quercus alba (white oak)	1.09 (0.41-2.54)
Quercus rubra (red oak)	3.72
Quercus velutina (black oak)	4.51 (3.29-6.13)

Black oak and red oak contain a greater total average of phenolics in the acorns does than white oak.

Toxic plant chemicals:

gallic acid
pyrogallol
tannic acid

References:

Basden, K. W., Dalvi, R. R. 1987. Determination of total phenolics in acorns from different species of oak trees in conjunction with acorn poisoning in cattle. Vet. Hum. Toxicol., 29: 305-306.

Animals/Human Poisoning:

Note: When an animal is listed without additional information, the literature (as of 1993) contained no detailed explanation.

Cattle

General symptoms of poisoning:

anorexia
constipation
depression
kidney failure
teeth grinding

Notes on poisoning:

Cattle that ingest a small number of acorns may show some loss of condition. However, they often develop a preference for eating the acorns. Toxic amounts cause depression, anorexia, constipation, the passing of small fecal balls covered in mucous and blood, teeth grinding, and submandibular edema. Death is usually caused by kidney failure. Postmortem findings reveal a large number of acorns in the rumen, gastroenteritis in the caudal portion of the digestive tract, and small, shrunken kidneys with diminished reserve capacity. If renal stress occurs, the reserve function of the kidney may be exceeded. Perirenal edema and hemorrhagic enteritis were the prominent lesions. Multifocal necrosis of the proximal convoluted tubules of the kidney is characteristic (Sandusky et al. 1977, Cockrill and Beasley 1979).

References:

Cockrill, J. M., Beasley, J. N. 1979. Renal damage to cattle during acorn poisoning. Vet. Med. Small Anim. Clin., 74: 82, 84-85.

Horses

General symptoms of poisoning:

abdominal pains
anorexia
colic
constipation
depression
diarrhea
hematuria
icterus

Notes on poisoning:

Horses that ingested leaves of red oak developed symptoms of depression, anorexia, abdominal pain, constipation, slight icterus, hematuria, edema, and weakness. The symptoms occurred 6-9 days after ingestion. Blood transfusions were thought to speed recovery (Duncan 1961).

References:

Duncan, C. S. 1961. Oak leaf poisoning in two horses. Cornell Vet., 51: 159-162.

Sheep