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Details of the management, feeding, level of activity and routine health care of horses in Scotland and the five northernmost counties in England were recorded through a stratified random sample of horse owners who had responded to a previous survey. Sixty-eight per cent of the horses were kept where their owners resided, and 32 per cent were kept away from the owner's home. More than 99 per cent were turned out to grazing for at least part of the year and 81 per cent were stabled for at least part of the time, most commonly bedded on straw (50 per cent) or shavings (34 per cent). Hay was fed to 87 per cent, sugar beet pulp to 64 per cent and commercially prepared concentrate mixes to 60 per cent of the horses. Hacking was the most popular activity (52 per cent of horses) followed by riding/pony club events (28 per cent) and showing (21 per cent). The majority of the horses were involved in more than one activity. There were an estimated 0.88 veterinary visits per horse per year and 29 per cent of the horses were reported to suffer from at least one permanent or recurrent health disorder. The median annual numbers of administrations of vaccines (influenza and tetanus) and anthelmintics were one and seven respectively per horse, and each horse was shod a median seven times. There were significant differences in the management of horses kept in different types of premises and in areas of different human population density.  相似文献   
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Two mature breeding stallions were evaluated because of specific ejaculatory dysfunction, and each was found to have aortic-iliac thrombosis occluding 60 to 70% of the aortic lumen. In each case, the stallion had strong libido, normal mounting, and vigorous initial thrusting. With continued exertion, thrusting became weak and dismount was awkward. Treatment aimed at maximizing sexual arousal before mounting and reducing hind limb pain and exertion during breeding allowed these stallions to continue breeding. A program of gradually increasing daily exercise also was associated with improved breeding performance during subsequent breeding seasons. In cases of specific ejaculatory dysfunction, aortic-iliac disease should be included among the differential diagnoses.  相似文献   
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Equine herpesvirus abortion in Australia 1977 to 1982   总被引:1,自引:0,他引:1  
Until 1977 no case of abortion caused by equine herpesvirus 1 (EHV1) had been recorded in Australia although the virus, called equine rhinopneumonitis virus, had been known to have been present at least since 1962. Outbreaks of EHV1 abortion occurred in New South Wales in 1977 and in 1981. Sporadic cases of EHV1 abortion had been confirmed in some parts of Australia each year since 1975. It was concluded that an abortigenic subtype of EHV1 had been introduced to Australia in 1977 and that the previously endemic respiratory subtype occasionally caused abortion. Virus isolation in a variety of cell cultures and histopathological examination of tissue were shown to be satisfactory methods of diagnosis of EHV1 abortion. Lung proved to be the specimen of choice. Slight serological differences between "abortigenic" and "respiratory" subtypes of EHV1 were found in cross neutralisation tests. A serological survey of 219 Sydney horses of various ages revealed that most yearlings had already acquired neutralising antibody to both subtypes.  相似文献   
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An outbreak of perinatal foal mortality associated with a herpesvirus is described. Twenty two foals either were still-born, or died soon after birth, or were weak and soon developed severe respiratory signs, or were normal at birth and developed respiratory symptoms 18 to 24 hours later. Elevated temperatures, heart and respiratory rates were constant features. The animals were severely leucopaenic, and showed an absolute neutropaenia. At autopsy the lungs were enlarged, and showed varying degrees of aeration and moderate to severe oedema and congestion. Histopathology showed an acute focal necrotising bronchiolitis with the presence of intranuclear eosinophilic inclusion bodies. Herpesvirus was recovered from 9 foals in cell culture and identified by electron microscopy.  相似文献   
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笋用竹害虫天敌资源研究   总被引:1,自引:0,他引:1  
本文报道了浙江省笋用竹害虫天敌资源调查的结果,共查明天敌资源44种,经鉴定属于螳螂目1科2种,半翅目1科2种,蛇蛉目1科1种,脉翅目1科2种,鞘翅目2科9种,双翅目2科2种,膜翅目9科22种;蛛形纲蜱螨目1科1种,蜘蛛目3科3种,指出了天敌的寄主和分布。  相似文献   
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Effects of adding different concentrations of melatonin (10?7, 10?9 and 10?11 M) to maturation (Experiment 1; Control, IVM  + 10?7, IVM  + 10?9, IVM  + 10?11) and culture media (Experiment 2; Control, IVC  + 10?7, IVC  + 10?9, IVC  + 10?11) were evaluated on in vitro bovine embryonic development. The optimal concentration of melatonin (10?9 M) from Experiments 1–2 was tested in both maturation and/or culture media of Experiment 3 (Control, IVM  + 10?9, IVC  + 10?9, IVM /IVC  + 10?9). In Experiment 1, maturated oocytes from Control and IVM  + 10?9 treatments showed increased glutathione content, mitochondrial membrane potential and percentage of Grade I blastocysts (40.6% and 43%, respectively). In Experiment 2, an increase in the percentage of Grade I blastocysts was detected in IVC  + 10?7 (43.5%; 56.7%) and IVC  + 10?9 (47.4%; 57.4%). Moreover, a lower number and percentage of apoptotic cells in blastocysts were observed in the IVC  + 10?9 group compared to Control (3.8 ± 0.6; 3.6% versus 6.1 ± 0.6; 5.3%). In Experiment 3, the IVC  + 10?9 treatment increased percentage of Grade I blastocysts with a lower number of apoptotic cells compared to IVM /IVC  + 10?9 group (52.6%; 3.0 ± 0.5 versus 46.0%; 5.4 ± 1.0). The IVC  + 10?9 treatment also had a higher mRNA expression of antioxidant gene (SOD 2) compared to the Control, as well as the heat shock protein (HSPB 1) compared to the IVM  + 10?9. Reactive oxygen species production was greater in the IVM /IVC  + 10?9 treatment group. In conclusion, the 10?9 M concentration of melatonin and the in vitro production phase in which it is used directly affected embryonic development and quality.  相似文献   
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