Harris P A
Animal Health Trust, Newmarket, Suffolk.
Vet Rec. 1990 Nov 10;127(19):468-70.
An outbreak of muscle stiffness and poor performance among 59 thoroughbreds at a Newmarket flat racing yard was investigated between the beginning of May and the end of June 1986. Over a third of the horses showed signs of muscular stiffness, and 38 had, at one or more of the sampling times, creatine kinase (CK) activities above 200 iu/litre and, or, aspartate aminotransferase (AST) activities above 300 iu/litre when they were sampled six to eight hours after exercise. The following season, at a similar time and stage of training, only four of 39 horses sampled had CK activities between 200 and 300 iu/litre, and three had AST activities between 500 and 600 iu/litre. Plasma samples from 18 animals sampled at the start of the investigation and 13 days later were tested for the presence of antibodies to equine herpesvirus (EHV). Ten of them showed a response highly suggestive of an EHV-1 infection. No significant abnormality was found in the fractional electrolyte values from seven randomly selected animals. Unusually high numbers of normally sized and stained fibres with centrally placed nuclei as well as groups of small muscle fibres were found in muscle biopsies taken from three animals which continued to have high enzyme activities and show recurrent signs of muscle stiffness.
1986年5月初至6月底，对纽马克特平地赛马场的59匹纯种马中出现的肌肉僵硬和表现不佳的疫情进行了调查。超过三分之一的马匹表现出肌肉僵硬的迹象，38匹马在运动后6至8小时采样时，在一个或多个采样时间点，肌酸激酶（CK）活性高于200国际单位/升，和/或天冬氨酸转氨酶（AST）活性高于300国际单位/升。在接下来的赛季，在类似的训练时间和阶段，采样的39匹马中只有4匹的CK活性在200至300国际单位/升之间，3匹的AST活性在500至600国际单位/升之间。对调查开始时和13天后采样的18只动物的血浆样本进行了马疱疹病毒（EHV）抗体检测。其中10只显示出高度提示EHV - 1感染的反应。从7只随机选择的动物中获取的电解质分数值未发现明显异常。在从3只酶活性持续较高且反复出现肌肉僵硬迹象的动物身上采集的肌肉活检样本中，发现了数量异常多的正常大小和染色的、核位于中央的纤维以及小群肌纤维。
