170:
In the early stages of disease, horses with shivers are commonly used as riding and driving animals. However, the disease is often slowly progressive. Muscle spasms usually increase in frequency and severity, and the animal becomes weak, develops muscle wasting, and may become very uncomfortable. The
149:
for a period of time at the height of flexion, before the limb is slowly extended and the foot is placed on the ground. This pause may last for seconds to several minutes, during which time there is spasming of the muscles of the hind limb and tail, leading to trembling ("shivers"). Similar signs may
117:
Clinical signs may be unilateral or bilateral, continuous or intermittent. They often worsen with excitement, stress, when the animal is asked to move on slippery surfaces, or during prolonged periods of standing. While shivers is classically associated with the hind end, horses may also occasionally
158:
Although most horses are usually clinically normal when standing, some may stand rigidly with the hind legs in full extension behind their body, heels lifted, supporting their weight only on their toes. Others may intermittently flex and abduct their hind legs, with associated muscle spasms, when
118:
show spasmodic contraction of the muscles of the head and neck, including twitching of the ears and lips, and rapid blinking. Rarely, horses will show a spastic gait in the front limbs in which the leg is held in full extension or with the knee flexed, with trembling occurring in the upper limb.
90:
Clinical signs usually are present before the age of 5 years old, and slowly progress throughout the horse's lifetime. Affected horses display muscle tremors of the hindquarters, hind limbs, and tail, and a spastic gait when they are asked to back up. Typical signs of shivers include:
154:
work, especially when the foot is hammered during shoeing. Horses may progress to a point where they show hyperflexion and abduction of the hind limbs for a few steps after being asked to move forward or turn. In advanced cases, the horse may be unable to move backwards.
141:
In mild cases, shivers may present only when the horse is asked to move backwards, usually seen as trembling in the muscles of the hind limbs and sudden, upward jerks of the tail. Affected animals may also snatch up their foot when asked to lift it for cleaning.
414:
Draper, A.C.; Trumble, T.N.; Firshman, A.M.; Baird, J.D.; Reed, S.; Mayhew, I.G.; MacKay, R.; Valberg, S.J. (March 2015). "Posture and movement characteristics of forward and backward walking in horses with shivering and acquired bilateral stringhalt".
27:
disorder of horses. It is characterized by muscle tremors, difficulty holding up the hind limbs, and an unusual gait when the horse is asked to move backwards. Shivers is poorly understood and no effective treatment is available at this time.
311:
Valberg, S.J.; Lewis, S.S.; Shivers, J.L.; Barnes, N.E.; Konczak, J.; Draper, A.C.; Armién, A.G. (November 2015). "The equine movement disorder "shivers" is associated with selective cerebellar
Purkinje cell axonal degeneration".
78:
The strong breed predilection suggests a genetic basis to the disease. Despite some similarities in breed prevalence, there is no evidence to suggest a link between equine shivers and
159:
asked to stand still for long periods. Severely affected animals become weak, develop muscle atrophy in the hind limbs, and may fall or become reluctant to lie down when confined.
231:
Draper, A.C.; Bender, J.B.; Firshman, A.M.; Baird, J.D.; Reed, S.; Mayhew, I.G.; Valberg, S.J. (March 2015). "Epidemiology of shivering (shivers) in horses".
192:
79:
461:
167:
There is currently no known effective treatment, although additional dietary vitamin E and selenium is often added following diagnosis.
389:
171:
horse may become unable to hold its feet up for trimming by a farrier, although use of alpha-2 agonist drugs, such as
133:). There are usually no changes on serum biochemistry profile, including measurements of muscle enzymes (CK and AST).
145:
More severely affected horses will produce a backward gait where the hind legs are lifted abnormally high, held
456:
146:
64:
The cause of shivers is currently unknown. Horses with shivers have been shown to have degeneration of the
53:
202:
349:"Prevalences and clinical signs of polysaccharide storage myopathy and shivers in Belgian draft horses"
40:), and they are more commonly male (3:1 ratio of males to females). Shivers is most often seen in
432:
370:
329:
248:
424:
360:
321:
240:
130:
450:
72:
24:
280:
49:
365:
348:
125:, horses with shivers do not show clinical signs typical of cerebellar disease (
45:
37:
197:
180:
176:
122:
69:
347:
Firshman, Anna M.; Baird, John D.; Valberg, Stephanie J. (15 December 2005).
325:
41:
436:
374:
333:
252:
179:, has proven helpful in reducing signs during farriery visits. Eventually,
172:
151:
428:
244:
150:
be seen when the horse is asked to simply lift a hind foot, or during
126:
388:
Baird, John D.; Firshman, Anna M.; Valberg, Stephanie J. (2006).
65:
36:
Most horses with shivers are tall (average affected horse is 17
183:
is often elected due to poor quality of life for the animal.
52:, but has also been reported in light harness horses, hacks,
353:
Journal of the
American Veterinary Medical Association
75:, although Purkinje cell number remains normal.
226:
224:
222:
220:
218:
8:
390:"Shivers (shivering) in the horse: a review"
364:
214:
306:
304:
302:
193:Equine polysaccharide storage myopathy
80:equine polysaccharide storage myopathy
285:University of Minnesota Equine Center
274:
272:
270:
268:
266:
264:
262:
7:
121:Despite histologic changes in the
14:
279:Valberg, Stephanie; Baird, John.
98:Muscle twitching/trembling (85%)
95:Farriery problems (96% of cases)
56:, and other light horse breeds.
1:
287:. University of Minnesota CVM
366:10.2460/javma.2005.227.1958
478:
462:Equine injury and lameness
397:Proc Am Assoc Equine Pract
137:Progression of the disease
110:Exercise intolerance (33%)
417:Equine Veterinary Journal
233:Equine Veterinary Journal
23:, is a rare, progressive
326:10.1177/0300985815571668
101:Elevated tail head (74%)
163:Treatment and prognosis
113:Facial twitching (19%)
107:Reduced strength (33%)
203:Cerebellar abiotrophy
314:Veterinary Pathology
104:Muscle atrophy (44%)
429:10.1111/evj.12259
245:10.1111/evj.12296
131:intention tremors
469:
441:
440:
411:
405:
404:
394:
385:
379:
378:
368:
344:
338:
337:
308:
297:
296:
294:
292:
276:
257:
256:
228:
21:equine shivering
477:
476:
472:
471:
470:
468:
467:
466:
447:
446:
445:
444:
413:
412:
408:
392:
387:
386:
382:
359:(12): 1958–64.
346:
345:
341:
310:
309:
300:
290:
288:
278:
277:
260:
230:
229:
216:
211:
189:
165:
139:
88:
62:
34:
12:
11:
5:
475:
473:
465:
464:
459:
457:Horse diseases
449:
448:
443:
442:
406:
380:
339:
320:(6): 1087–98.
298:
258:
213:
212:
210:
207:
206:
205:
200:
195:
188:
185:
164:
161:
138:
135:
115:
114:
111:
108:
105:
102:
99:
96:
87:
86:Clinical signs
84:
73:Purkinje cells
61:
58:
54:Quarter Horses
33:
30:
13:
10:
9:
6:
4:
3:
2:
474:
463:
460:
458:
455:
454:
452:
438:
434:
430:
426:
423:(2): 175–81.
422:
418:
410:
407:
402:
398:
391:
384:
381:
376:
372:
367:
362:
358:
354:
350:
343:
340:
335:
331:
327:
323:
319:
315:
307:
305:
303:
299:
286:
282:
275:
273:
271:
269:
267:
265:
263:
259:
254:
250:
246:
242:
238:
234:
227:
225:
223:
221:
219:
215:
208:
204:
201:
199:
196:
194:
191:
190:
186:
184:
182:
178:
174:
168:
162:
160:
156:
153:
148:
143:
136:
134:
132:
128:
124:
119:
112:
109:
106:
103:
100:
97:
94:
93:
92:
85:
83:
81:
76:
74:
71:
67:
59:
57:
55:
51:
50:Thoroughbreds
47:
43:
39:
31:
29:
26:
25:neuromuscular
22:
18:
420:
416:
409:
400:
396:
383:
356:
352:
342:
317:
313:
289:. Retrieved
284:
239:(2): 182–7.
236:
232:
169:
166:
157:
144:
140:
120:
116:
89:
77:
63:
60:Pathogenesis
48:breeds, and
35:
32:Presentation
20:
16:
15:
46:draft horse
451:Categories
403:: 359–364.
209:References
198:Stringhalt
181:euthanasia
177:detomidine
123:cerebellum
70:cerebellar
42:Warmbloods
281:"Shivers"
68:of their
437:24612176
375:16379634
334:25714471
253:24802303
187:See also
173:xylazine
152:farriery
147:abducted
82:(PSSM).
291:13 June
17:Shivers
435:
373:
332:
251:
127:ataxia
393:(PDF)
66:axons
38:hands
19:, or
433:PMID
371:PMID
330:PMID
293:2015
249:PMID
425:doi
361:doi
357:227
322:doi
241:doi
175:or
453::
431:.
421:47
419:.
401:52
399:.
395:.
369:.
355:.
351:.
328:.
318:52
316:.
301:^
283:.
261:^
247:.
237:47
235:.
217:^
129:,
44:,
439:.
427::
377:.
363::
336:.
324::
295:.
255:.
243::
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.