Common Signs & Symptoms of Plant Toxicity

    It is necessary to know a particular equine’s normal behavior patterns, as the foremost indicator of a toxic event is any significant change in an animal’s behavior.  Any inconsistency or unusual behavior should be cause for concern.  It is possible for behavioral changes to result from other disorders, such as problem teeth, but many plant toxins can result in mortality fairly quickly, so caution is advised. Consultation with a veterinarian or toxicologist is the most accurate method of obtaining a diagnosis in plant toxicity in equines.

    However, there are some physiological and behavioral warning signs generally present in poisoning by plants.  Some of the more common physical and behavioral symptoms include changes in appetite, observable physical trauma, digestive changes, neurological symptoms, and muscle weakness or lameness.

• Appetite and related changes

Decreased appetite, refusal to eat customary foods, evidence that the animal is eating unusual plants or materials, lack of ability to recognize food when it is presented, chewing when food is absent, rapid weight loss, refusal to drink or excessive consumption of water, frequent lipping of or splashing in water: all are signals that there may be ingestion of a toxic plant involved.

• Easily recognized externally physical symptoms

Physical symptoms such as drooling, excessive salivation, blisters, ulceration, cuts, lesions, severe or painful skin conditions, sunburn to light or white areas, loss of hair coat: these may be signs of ingestion of or contact with physically injurious, photosensitizing, or toxic plants.

• Digestive trouble or changes

Digestive problems or changes such as diarrhea, hard, dark, or bloody feces, lack of elimination, abdominal distention, urine that is unusual or dark in color, flatulence, pain with elimination, unusual odors on the animal’s breath, or any of the symptoms of colic listed in the previous section: these may be symptomatic of plant toxins that act on the digestive system.

• Neurological symptoms

Neurological signs such as decreased vision, odd gait, lack of coordination, poor balance, convulsions, circling, abnormal reaction to common stimuli, tremors, fearfulness or anxiety, rolling eyes, and excessive or unusual friendliness or aggression: any of these may be signs of the ingestion of plant toxins that affect the nervous system.

• Muscle weakness or lameness

Lameness or inability to stand, weakness, refusal to put weight on a leg or legs, joint tenderness, refusal to move, stiffness, leg or limb swelling or edema: all may be symptoms of the ingestion of certain classes of toxic plants.

 

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