The Vet's Corner - Epilepsy in Red-Lored Amazons

Abstract

Introduction

During the last four years, we have noted many cases of apparent idopathic epilepsy in red Jared Amazon parrots (Amazona autumnalis autumnalis, Amazona autumnalis saluini, Amazona autumnalis lilacina, and Amazona autumnalis diadema). The rather high rate of this condition in this relatively rare species leads us to believe that the condition may be a syndrome and worth relating to the membership.

Background

Epilepsy has been occasionally noted by the authors and others in double yellow-headed Amazons', mynah birds, and others. True idiopathic epilepsy seems to be rare in avian species. The diagnosis is usually made after ruling out other causes of seizures such as hypocalcemia 2, encephalitis (bacterial or viral), toxins such as lead poisoning,3~ etc., hypoglycemia in birds of prey but not in psittacines>, trauma, parasites, hepatic encephalopathy, neoplasia, vitamin deficiency problems, etc. As in canines and humans, the affected birds may appear normal between convulsions. In severe cases, the bird may appear paranoid or hyperactive, possibly from the anticipation of more frequent seizure activity.

Four subspecies of red-lored Amazons are known.6 Most seen in practice are the Mexican variety (Amazona autumnalis autumnalis). Our cases have all been of this variety except for one case in an Amazona autumnalis salvini (Salvin's Amazon).

In our practice, we have seen at least ten cases of idopathic epilepsy in redloreds. Our colleagues and clients have described many other probable cases. Considering how rare the condition seems to be in caged birds (with the possible exception of the mynah bird), there seems to be a disproportionate number of these birds. We, therefore, consider the condition a syndrome. One can only speculate on the etiology, but genetic factors seem most likely.

Case Reports

Three cases, typical of what we have been seeing, will be described. Two alternate modes of treatment were used.

CaseNo.1

A three year old red-lored Amazon was referred to us in November of 1983 for treatment of a seizure disorder. The owner informed us that the bird would "fall" two to three times each night. These falling spells would seem to crescend to an "attack" His first seizure (several months previously) resulted in severe head trauma with resultant hemorrhages. Also, his right leg or foot seemed to bother him and his grip was not normal as a result. The bird appeared frightened of everything, even food at times, according to the owner. His judgement of depth perception was off, and the owner described frequent twitching and shivering. The owner also described abnormal behavior such as lateral head tipping and staring at the ceiling. At other times, the bird would appear normal. The owner commented that no "attack" was ever the same.

A physical exam revealed no obvious abnormalities. The bird appeared bright, alert, and responsive, had normal integument, normal weight (329.0 g), and no orthopedic abnormalities were evident ( despite the fact that the owner felt that the right leg or foot was "bothering" the bird).

A hematological work-up revealed a slight basophilia and slightly elevated uric acid value. A blood lead (SmithKline Labs) reading was normal at 13 mg/dl.

The bird was sent home on phenobarbitol elixer (20mg/5ml) at a dose of 0.30 ml orally b.i.d.

The owner informed us two days later that the bird seemed improved. There were no signs of drowsiness or depression. The bird was playing and no seizures had been noted. The owner was very pleased and described the bird as almost 100% normal. At this time the phenobarbitol dose was increased to 0.40cc b.i.d. to compensate for some of the medication lost in the owner's attempts at administration.

Two days later the owner was contacted. The owner said that after increasing the dose to 0.40cc, the bird started acting "zombie-like" and she reduced the dose to 0.30cc. The owner was advised not to give further doses in the evening or the morning of the next day. If the bird was still "trance-like.' we would decrease the doses to 0.30cc once daily. The next day the bird experienced a minor seizure.

Two days later, the bird panicked when his cage cover was removed and began screaming and trying to fly. The owner began administering 0. 20cc phenobarbitol b.i.d. Despite the setbacks, the bird was considered greatly improved by the owner.

The bird stabilized over the next two weeks on 0.20cc b.i.d. The bird began to regress when the dose was reduced to 0.15cc b.i.d.

Two weeks later the bird seemed to show hyperactivity, "paranoia;' and aggressiveness. The dosage was increased to 0.25cc twice daily at that time. On the higher dose the bird did not seem drugged to the owner this time. The owner felt that the effects would last eight to ten hours, and then some "paranoia" would be evident.

For the last one and one-half years, the bird has been maintained on phenobarbi tol at a dosage of 0.25cc twice daily. Very minor seizure activity occurs periodically but is quite tolerable to the owner. The bird has been quite healthy and currently weighs 352.0g. The owner refills the bird's prescriptions and administers the medication regularly.