摘要:

Individual nerve fibres were isolated from the recurrent laryngeal and some distal hindlimb nerves, in an investigation of equine laryngeal hemiplegia. One hundred teased fibres were obtained from each of three sampling sites on both left and right recurrent laryngeal nerves, from 15 thoroughbred horses. These fibres were graded descriptively and internode lengths measured. A distal distribution of pathology was demonstrated in all groups studied, but was most severe in the clinical group of horses. The predominant change was one of short thinly myelinated internodes interspersed amongst normally myelinated internodes, indicating remyelination of previously demyelinated areas of nerve fibre. Such pathological change was also reflected by the decreased mean internode length, and its increased variability associated with disease. However, it was determined statistically that these abnormal internodes were grouped along particular nerve fibres, rather than being randomly distributed between all nerve fibres. This is thought to indicate myelin sheath changes secondary to underlying axonal pathology. Thus it was concluded that the primary pathology was likely to be axonal in nature, while the high incidence of demyelination changes was a reflection of the chronic nature of the disease process. Thus, the distal distribution of pathology, the primary axonal involvement, the presence of changes in left and right recurrent laryngeal and distal limb nerves, all support the classification of equine laryngeal hemiplegia as a distal axonopathy.

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35342

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

This study confirmed that neurogenic muscle pathology exists in intrinsic laryngeal muscles supplied by the recurrent laryngeal nerves in horses subclinically and clinically affected with laryngeal hemiplegia. An important additional observation was the occurrence in three out of four laryngeal hemiplegic horses of neurogenic muscle changes in a hindlimb muscle, theextensor digitorum longus, a muscle supplied by another long peripheral nerve. This finding suggests that a polyneuropathy exists in laryngeal hemiplegic horses, and supports the classification of this disease as a distal axonopathy. Comparison of the degree of pathology in the intrinsic laryngeal muscles and that of the recurrent laryngeal nerves innervating them, demonstrated a strong correlation between the extent of damage in the distal left recurrent laryngeal nerve and the overall degree of muscle pathology. The muscle damage in clinically affected horses is a reflection of the nerve damage present in the most distal portion of the recurrent laryngeal nerve. The more variable pathological changes found in proximal levels of the left and right recurrent laryngeal nerves probably reflects the ongoing nature of the pathological process affecting nerve fibres. The existence of a subclinically affected group of horses, the earliest involvement of an adductor, the leftcricoarytenoideus lateralismuscle, and the presence of changes in the right intrinsic laryngeal muscles all confirmed the findings of previous workers.

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35343

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Evidence of long central nerve fibre degeneration (axonal spheroids) in the lateral cuneate nuclei was found in all eight thoroughbreds affected clinically and subclinically with equine laryngeal hemiplegia, but in only one of six control animals. It was considered that these spheroids may signify a central nervous component of the disease process of laryngeal hemiplegia although until further investigations are performed no firm conclusions regarding the relationship of these findings with laryngeal hemiplegia could be made. Examination of the left and rightnucleus ambiguusof clinical and subclinical laryngeal hemiplegic horses revealed no pathological alterations.

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35344

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

A serological study of hairy shaker disease (HSD) was carried out on a group of 30 Romney two-tooth ewes and their Iambs over a two year period.

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35345

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35347

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35348

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35349

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor