Poisonous Plants

Pinus ponderosa Minimize
PONDEROSA PINE Pinus ponderosa

Pinus ponderosa


Pines are evergreen trees with narrow needles in bunches of two or three. Seeds are borne in a characteristic cone. The ponderosa pine grows to a height of 60-80'. It is a native pine with long, medium green needles and a broad, open, rounded habit. Winter color is yellowish-green. Fragrant, cinnamon-colored bark and ornamental cones. Spread 45'. Grows to 9000'.
Geographic range
Ponderosa pine ranges in the mountains of the northwestern United States. Loblolly pine is found in the eastern and southeastern United States.
Toxic principle
The abortifacient constituent is isocupressic acid, a labdane diterpene acid.
Substantial intake of pine needles for several days is associated with abortions.
Experimental evidence suggests that progesterone-producing cells in both the placenta and corpus luteum are affected, resulting in ¯ circulating progesterone concentrations.
Clinical Signs
Abortion is common in the last trimester of pregnancy often accompanied by edema of the udder and vulva in the dam. Abortions are characterized by weak uterine contractions, occasional incomplete cervical dilatation, excessive mucous discharge, birth of a small, weak calf and retained fetal membranes. Complications subsequent to abortion are frequent and include septic metritis, agalactia, rumen statis and death. Occasionally, cows die from an apparent toxicosis induced by the pine needles; death may be due to toxins other than isocupressic acid.
Laboratory diagnosis
not available, dimunition of serum progesterone concentrations occurs.
due to complications following abortion.
Remove from source
Measures include providing supplemental feed to reduce pine needle consumption and restricting access of pregnant cattle to pine needles.
Effect on Animals Minimize
Cow with spontaneous abortion caused by ingestion of Pinus Ponderosa.

Cow with spontaneous abortion caused by ingestion of Pinus Ponderosa.
Affected cow with metritis and vaginal discharge.

Affected cow with metritis and vaginal discharge.
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