Table 5.

Hyperkinetic disorders in domestic animals, possibly including dystonic signs.

Species	Breeda	Characteristics indicating the presence of dystonia	Genetic defect/pathophysiology	Denomination in veterinary medicine	Assumed comparable type of human dystonia
Dog	Cavalier King Charles Spaniel	Episodes of involuntary twisting movements and abnormal postures of trunk and extremities with muscular hypertonicity, resulting in complete immobility	Autosomal-recessive mode of inheritance 15.7 kb deletion in the gene BCAN (encoding brain-specific extracellular matrix-proteoglycan brevican)	Episodic falling/hypertonicity/sudden collapse	Paroxysmal (non-)kinesiogenic dystonia
		Episodes are inducible by excitement/stress or exercise
		Duration of episodes: up to minutes
		Consciousness is unaltered
		Treatment with benzodiazepines (clonazepam 0,5 mg/kg) and carbonic anhydrase inhibitors (acetazolamide) can be attempted
	Scottish Terrier	Episodes of involuntary movements, starting with an increase in muscle tone and arching of the back, stiffness of extremities resulting in loss of balance	Unknown/autosomal-recessive mode of inheritance serotonergic and/or dopaminergic dysfunctions are presumed	Scottie cramp	Paroxysmal (non-)kinesiogenic dystonia
		Episodes are inducible by stress and effort/exercise as well as by amphetamine (induces dopaminergic overactivity)
		Duration of episodes: up to minutes
		Consciousness is unaltered
		EMG abnormalities
		Treatment with benzodiazepines (diazepam 0,5–1,5 mg/kg)
	Chinook dog	Episodes of involuntary twisting movements and abnormal postures of trunk and extremities with muscular hypertonicity, partly with head tremor	Unknown/probably autosomal-recessive mode of inheritance	Chinook seizures	Paroxysmal dyskinesia
		Trigger: uncertain
		Duration of episodes: up to 1 h
		Consciousness is unaltered
	Border Terrier	Episodes of involuntary movements	Unknown	Canine “epileptoid” cramping syndrome	Paroxysmal non-kinesiogenic dystonia
		Episodes are inducible by excitement and waking from sleep
		Often associated with mild tremor and gastrointestinal signs (borborygmi, vomiting and diarrhea)
		Duration of episodes: 2–30 min up to three times per day
	Yorkshire Terrier	Episodes of generalized, sustained and painful involuntary muscle contractions	Unknown/case report no changes found by MRI and CT	–	Paroxysmal hyperkinetic disorder
		Duration of episodes up to 30 min, four times per day
		Consciousness is unaltered
	Boxer	Episodes of twisting movements and postures of trunk and extremities with muscle hypertonicity, torticollis, and “grimacing”	Unknown/hereditary	–	Paroxysmal dystonia
		Episodes are inducible by excitement
		Duration of episodes: ~1–5 min
		Consciousness is unaltered
	Bichon Frisé	Episodes of abnormal twisting movements and postures of trunk and extremities, kyphosis, and “grimacing”	Unknown/case report	–	Paroxysmal hyperkinetic disorder
		Episodes occur spontaneously also at rest or are inducible by excitement/stress/effort
		Consciousness is unaltered
	German shorthaired pointer	Episodes of abnormal twisting movements and postures of trunk and extremities	Unknown/case report	–	Paroxysmal hyperkinetic disorder
		Episodes are inducible by stress/excitement/effort
		Duration of episodes: 10 min to 3 h
		Consciousness is unaltered
		Successful treatment with phenobarbital (30 mg/kg)
	Dalmatian dog	Hyperkinetic episodes with rigidity/hyperextension/twisting movements and postures of extremities as well as head and neck (torticollis), rigidity of paraspinal muscles, resulting in scoliosis and loss of balance/falling and immobility	Unknown/case report	–	Paroxysmal hyperkinetic disorder
		Episodes are inducible by excitement/stress and exercise
		Duration of episodes: ~15–60 min
		Consciousness is unaltered
		Successful treatment with azetazolamide (0,1 mg/kg)
	Great Dane	Bilateral blepharospasm	Unknown/case report	–	Focal dystonia (blepharospasm)
		Successful therapy with local application of botulinum toxin A
Horse	Various breeds	Episodic occurrence of involuntary muscle contractions, mostly in the pelvic region and the hind limbs Episodes are inducible by exercise, stress and excitement Duration of episodes: seconds to minutes	Unknown/hereditary? End-terminal neuroaxonal lesion in the deep cerebellar nuclei	Shivering	Paroxysmal dystonia?
		Episodes of involuntary muscle contractions in the rear body parts but also in the nasolabial region	Unknown/	Stiff-horse syndrome	Paroxysmal dyskinesia?
		Episodes are inducible by exercise and excitement
Cattle	Various breeds	Progressive consistent contractions of the hindlimb muscles	Unknown possibly autosomal recessive (reduced penetrance?)	Bovine spastic paresis	Limb dystonia
	Belgian Blue, Chianina, Dutch Improved Red and White	Stress/effort and external stimuli provoke enhanced muscle tone, resulting in hyperflexion of all extremities and disability to stand or walk	Mutation in the gene ATP2A1 (encoding for a Ca2+-ATPase [SERCA1] leads to disturbances in the Ca2+-reuptake from the cytosol in the endoplasmic reticulum)	Congenital muscular dystonia type 1 (CMD1)	Brody myopathy? (not dystonia)
	Belgian Blue	Acoustic or tactile stimuli are leading to episodes of sustained muscle contractions with twisting, repetitive movements and postures	Microdeletion in the gene Glyt2 (SLC6A5) (encoding for a presynaptic transporter of glycine)	Congenital muscular dystonia type 2 (CMD2)	Hyperekplexia/startle disease? (not dystonia)

^aFor references, see text section.