Urinary incontinence and incoordination in three horses associated with equine protozoal myeloencephalitis

Urinary incontinence, weakness and ataxia associated with equine protozoal myeloencephalitis (EPM) was diagnosed in three horses. Rectal examination of all horses revealed distention of the urinary bladder. Urine was expressed when manual pressure was applied to the bladder of each horse during rectal examination. The anal reflex and tone of the anus and tail were normal in all horses. Two horses had bacterial cystitis associated with Enterococcus sp. All horses were treated with pyrimethamine and a sulfonamide for EPM, but there was a variable response to treatment.     

黄河干流头道拐水文站水沙运动特征及影响因素

为明确黄河干流头道拐水文站水沙运动过程、变化趋势及运动状态特征,以2006—2018年黄河干流头道拐水文站水沙数据为基础,基于累积距平法、R/S极差分析法、河道来沙系数与不协调度等研究方法,对头道拐水文站水沙运动过程进行系统分析。结果表明:头道拐水文站年际间径流与输沙量和年内月均径流与输沙量变化趋势均呈现良好的一致性,但两者的季节性差异特征显著,且输沙量的显著性较径流更突出;冬季径流与输沙量变化趋势同步性相比其他季节较差,季节性的极差Hurst指数揭示了冬季输沙量变化趋势的反持续性和水沙不协调性易引起河道的冲淤演变;以来沙系数为水沙状态的划分依据,春季、夏季和秋季水沙特征多呈现水少沙多的状态,而冬季水沙状态则为水多沙少,水沙协调状态会出现在春季个别年份;季节性水沙不协调度总体呈夏季>秋季>春季>冬季的变化特征,特殊的来水来沙过程、水文气候特征及人类活动变化是造成水沙不协调的主要影响因素。     

Spinal ataxia in a 2-year-old colt caused by a compressive primary vertebral osteosarcoma

Neoplasia is a rare cause of ataxia in horses. This report describes a 2-year-old colt presented with sudden-onset ataxia in which a cervical vertebral osteosarcoma causing severe compression of the spinal cord was diagnosed. Radiological changes included a large osteolytic lesion in the vertebral body, the vertebral arch, the right cranial articular process and the right transverse process of C4, interrupting the borders of the vertebral foramen and the right transverse foramen. Myelography revealed a marked spinal cord compression. Necropsy confirmed the presence of a well-demarcated, invasive and firm mass protruding from the fourth cervical vertebral body that led to severe compression of the spinal cord. In spite of its strongly pleomorphic nature, the detection of osteoid confirmed the diagnosis of a central osteosarcoma of the combined type. To the best of our knowledge, a primary single vertebral osteosarcoma causing ataxia in a juvenile horse has not previously been reported, and findings of this case report could help in the diagnostic work-up of similar cases.     

Cervical extradural haematoma in an ataxic horse

As neurological diseases in horses share many overlapping clinical signs, the veterinarian is required to know how to perform a focused evaluation of this system as well as how to carry out complementary examinations to establish an aetiological diagnosis. This is a case report of an ataxic horse presenting with an extradural haematoma in the region of the 7th cervical vertebra. The 7‐year‐old Criollo mare presented with clinical signs of ataxia grade 3 (scale 1–5) in all limbs and a proprioceptive deficit. Radiological evaluation did not show bone changes or narrowing of the cervical canal. Samples of blood, serum and cerebrospinal fluid were collected and tested negative for antibodies to equine herpes virus type 1–4, Trypanosoma evansi and Sarcocystis neurona. The disease evolution was followed over a 4‐week period, after which the animal showed worsening overall clinical signs, and thus euthanasia was performed. A necropsy did not reveal macroscopic changes in any organs, except for an extradural haematoma in the region of the 7th cervical vertebra causing spinal cord compression. Histological examinations showed that the nodular lesion consisted of fibrovascular tissue, granulation tissue at different stages of maturation, red blood cells, cellular debris, fibrin and macrophages. The white matter of the ventral horn of the spinal cord contained degenerative lesions. In addition, the brain tested negative for rabies virus encephalitis. Based on the history, the laboratory test results, anamnesis and the lesion observed at necropsy, it was concluded that the ataxia was due to spinal cord compression, which was caused by an extradural haematoma in the region of the 7th cervical vertebra. Evaluation of the equine neurological system is highly important in localising the area of lesions, and complementary examinations are useful in differentiating between diseases affecting this system. Spinal cord compression injuries, such as extradural haematomas, are rarely reported in the literature, and their pathophysiology is difficult to understand. Nevertheless, they should be included in the differential diagnosis of ataxia in horses.