Data/hora: 15/06/2024 11:56:44

Biblioteca(s): 	Embrapa Caprinos e Ovinos.	
Data corrente: 	23/04/1996	
Data da última atualização: 	23/04/1996	
Autoria: 	HILL, B. D.; O'DEMPSEY, N. D.; CARLISLE, C. H.	
Título: 	Cervicothoracic vertebral subluxation causing ataxia in sheep.	
Ano de publicação: 	1993	
Fonte/Imprenta: 	Australian Veterinary Journal, v.70, n.4, p.156-157, 1993.	
Idioma: 	Inglês	
Conteúdo: 	In the present cases no gross abnonnalities were observed in . cervical musculature. However, specific muscle groups, such as the longissimus ?rvicis, were not individually dissected for histopathological examination. It is likely that aIl the cases of cervicothoracic vertebral subluxation described above are the same en~ith perinatal myopathy as the precursor lesion. Affected lambs were never seen among the Queensland Merinos, probably because of the more extensive management system employed. Such lambs would have perished unnoticed in the field, whereas those with less severe defonnity would have survived pnd flrst been observed during mustering. The cause of the myopathy is not known, but it bas been suggested that subsequent fibrous contracture of neck muscles results in defor- mity of ?rvical and thoracic vertebrae by interfering with their nonnal growth (Nisbet and Renwick 1961). 
Humpyback. a disease of unknown aetiology affecting Merino sheep in western Queensland (D'Sullivan 1976), was the most important differential diagnosis for cervicothoracic vertebral subluxation in this investigation. Clinical signs, which characteristically appear while sheep are being driven. are a stiff-legged hind limb gait and knuckling over at the fetlocks. Affected sheep eventually stop and stand with their heads lowered and their backs arched. There is Wallerian degeneration throughout the length of the spinal cord. However, cases of humpyback have never been associated with deformities of the ?rvical column. This, together with the characteristic U-neck confonnation of sheep affected with vertebral subluxation should be sought in differentiating the 2 diseases. 
We are grateful for the assistance of Mrs K Reynolds, of the Queensland Veterinary School, for preparing the radiographs. The interest shown and assistance provided by the Lloyd family are gratefully acknowledged. 	
Thesagro: 	Ataxia; Ovino.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Caprinos e Ovinos (CNPC)	
Exemplares: 	CNPC - (2598-1) - ADC - AP - -- -  -  - 1996.00000 - DIS