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241.
For various anamnestic reasons the cervical vertebral column of 78 horses was examined radiologically. Statistical comparisons showed that male "warmbloods" were more frequently affected than was expected. Our horses were older than comparable animals in the international literature. Independently of their history the radiologic diagnosis of "cervical spondylarthrosis" was established in 56 horses. Arthrosis and other conditions were clinically manifested by spinal ataxia (44 horses) or mechanical impairment of the neck's mobility (21 horses). 10 of the arthrotic patients had synovial cysts causing compression of the spinal cord. 79 percent of all dorsal intervertebral arthrotic joints were found in the caudal column (C6/7 to C7/Th1). With 38 percent, C6/7 was the most frequently affected joint. Clinical and radiological findings could be compared with patho-anatomic results in 29 horses. The correlation was satisfactory.  相似文献   
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The concept of coping can be used to relate the environmental conditions provided for livestock to their responses--their productivity and their welfare. Pigs are "ecological generalists" and hence are "designed" to cope with a wide variety of environmental conditions. They, however, show clear limits to their adaptability both in terms of the space they require and the pen materials they can endure without injury. Even where they adapt to a wide range of conditions, there often is a particular environment that gives optimum performance. Examples of temperature requirements and feeding facilities are discussed. The process of coping is shown to impose a biological "cost" in some instances and, although a pig has adapted to a specific environment, questions still remain concerning whether keeping a pig in that environment is justifiable.  相似文献   
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1. The ostrich industry in South Africa (and elsewhere) experiences a high rate of embryo mortality during artificial incubation of eggs. Most of this mortality takes place in the last 10–14 d of incubation.

2. We carried out post‐mortem examinations on 111 embryos that died within this period to assess the causes of this mortality.

3. Malpositioning and severe oedema were the predominant symptoms of dead‐in‐shell embryos with 55% being malpositioned and 41% showing severe oedema. Of these, 22 embryos (24%) showed both symptoms. Malpositioning generally results from incorrect setting of the eggs or inadequate turning and oedema was significantly correlated with the amount of water lost from the eggs which in turn was correlated with egg size.

4. Myopathy, gross lesions of internal organs, haemorrhage, bacterial infections and congenital deformities were found in less than 10% of chicks examined for these symptoms.  相似文献   

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