When pastures are lush, equines show little interest in Nightshade. However, when conditions are dry and the pastures thin out, owners need to be vigilant about monitoring their fence lines and shaded areas to erridicate the deadly plants.
Nightshade is a common plant found in Wisconsin and much of North America. It is commonly seen along roadsides, under fences, and in tree lines. Several varieties exist, and all are toxic to equines and humans. The plants normally have a low tolerance for direct sunlight, preferring shaded, moist soil.
The most common variety has dull green leaves and bell-shaped flowers that are purple. These flowers develop into berries that turn from green to black. It is an attractive plant, and it is not unusual to see both flowers and berries at the same time.
Another variety is the yellow form, which has pale yellow flowers and berries.
Bitter Nightshade
Nightshade has atrophine-like effects on the nervous system and is one of the most toxic plants in the Western Hemisphere. According to Wikipedia, children have been poisoned by ingesting as few as three berries and the ingestion of one leaf can be deadly to an adult. The root is considered to be the most toxic, though this varies from specimen to specimen. All parts of the plant contain alkaloids.
As per the "Guide to Poisonous Plants" by Dr. A. B. Knight, signs of nightshade poisoning in equines can include:
- Excess salivation
- Dilated pupils
- Colic
- Diarrhea
- Kidney failure
- Muscle tremors and weakness
- Slow heart rate
- Labored breathing
- Depressions, drowsiness, incoordination
- Decreased cardiac output leading to shock, coma, and death
Supportive therapy including electrolytes, intravenous fluids, and intestinal protectants may be successful, but you should call your veterinarian immediately if you suspect your equine has gotten into nightshade.
Please contact your veterinarian with any questions you may have.
