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71.
Sayin F Dinçer S Karaer Z Cakmak A Inci A Yukari BA Eren H Vatansever Z Nalbantoglu S 《Tropical animal health and production》2003,35(6):521-539
An epidemiological survey for Theileria annulata infection was conducted in 12 selected villages around Ankara in Central Anatolia, Turkey, during the period April 1990 to January 1993. During the survey, 198 cattle of 30 local breeds, 84 Holstein-Friesian×local breeds and 84 Holstein-Friesian breed were examined for antibodies to T. annulata and the presence of the vector ticks. Four species of Hyalomma ticks were identified: Hyalomma anatolicum anatolicum, Hyalomma anatolicum excavtum, Hyalomma detritum and Hyalomma marginatum marginatum. Salivary gland staining indicated that infected adult ticks of all four species were present and, therefore, were implicated in the transmission of tropical theileriosis in the field. Generally, the Hyalomma infestation rate was low, with the heaviest infestations occurring on the older animals. Young adults and calves had very low infestation rates. Most ticks seen on cattle were adults, very few nymphs were found. The blood smear and serological examination of the 198 cattle conducted in March, before the start of the first disease season, showed that the prevalence of piroplasmosis was 11.1% (22 out of 198) and the seroprevalence of T. annulata was 10.6% (21 out of 198). Forty-three animals were then excluded from the study because they were seropositive and/or harboured piroplasms. Ninety-two seronegative animals showed piroplasmosis (92 out of 155) and 34 seronegative animals became seropositive for T. annulata (34 out of 155) during the three disease seasons. One animal became clinically ill with tropical theileriosis and required treatment. The incidence of cattle showing piroplasmosis and disease in the total study sample was 50.7% and 0.5% per disease season, respectively. The seroconversion rate of new infection with T. annulata in the total study was 14.3% per animal season. The number of cattle showing piroplasmosis was much greater than the number of seropositive cattle, which may indicate the presence of another species of Theileria. The two different management systems encountered in the study were considered to have influenced the tick infestation levels. 相似文献
72.
A study was made of bovine dermatophilosis on 540 animals at a high altitude (2400–2500 m above sea level) in Ethiopia. Eighty-two (15.4%) of the animals were affected by the disease which was more prevalent in local animals than was previously assumed. There was a significant (p<0.05) difference in the prevalence among different age groups. However, the difference in the prevalence of the disease between males and females was not significant (p>0.05). Associated risk factors included the relatively high average annual rainfall and humidity, tick infestation (76%) and management, related to the mixed crop-livestock production system. The possible impact of the disease on Ethiopian agriculture is indicated. 相似文献
73.
74.
曹立 《四川畜牧兽医学院学报》2007,5(3):23-26
金融市场是经济发展的资金基础和后盾,中部的发展需要中部金融市场的发展。文章通过对中部金融水平的现状描述,提出以武汉为中心建立区域金融中心的设想及具体措施,及组建中部开发银行,优化发展中部金融市场。 相似文献
75.
调查了紫茎泽兰(Eupatorium adenophorum Spreng)在金阳县的分布规律,为防止紫茎泽兰对金阳县农业生产和生态环境破坏提出了一些依据。本次调查了每个样方内的紫茎泽兰的植株数、平均高度、单株生物量和总生物量,发现紫茎泽兰的总株数从海拔1 650 m的3株增长到580 m的32 640株,极差达到32 637,变化极其显著;紫茎泽兰的平均高度和单株生物量变化也较大;同时发现紫茎泽兰的植株数、平均高度、单株生物量和总生物量随海拔的升高成负相关,其中单株生物量与海拔的相关性最显著,相关系数达到-0.937 4。 相似文献
76.
77.
通过调查资料分析,玉树县现有退化草地597533.3hm2,占可利用草场面积的43.56%。草地退化的主要原因是:超载过牧,鼠虫危害以及滥采乱挖等人为因素。并提出了加强草地建设,实施退耕还林(草),退牧还草和三江源生态保护治理等项目工程以及逐步完善和实行以法治草,建立人工草地等措施。 相似文献
78.
天祝县草产业发展的制约因素及其对策 总被引:1,自引:0,他引:1
通过分析天祝县草产业发展现状,指出天祝县草产业发展存在的问题,提出要大力发展天祝县草产业必须加强天然草原综合改良,科学合理利用草原资源,建立人工草地和牧草种子繁育基地,开发草产品;建立多元化的投入机制,培植草产业开发的龙头企业;进一步完善草地管理制度,全面彻底地落实草原有偿承包责任制;建立信息网络体系,把信息网络纳入畜牧业基础设施建设范围内,建立健全草畜产品信息网络。 相似文献
79.
Objective To measure the prevalence of megabacteria in budgerigar-breeding colonies and to evaluate possible methods to reduce the prevalence.
Design A monitoring study over several years.
Sample population Two budgerigar ( Melopsittacus undulatus ) colonies with over 300 birds each.
Procedure The prevalence of megabacteria in the faeces in two budgerigar breeding colonies, colony 1 and 2, was determined by faecal examination of each bird. Following an initial survey (1990), most of the birds that were scored 2+ or more were culled and a management practice was implemented to discriminate against positive birds. Consecutive yearly surveys (1991, 1992) were conducted on the young birds bred in these colonies. The prevalence of megabacteria in colony 2 was also evaluated in 1994 and 1996 after all the birds were treated with amphotericin B administered in drinking water.
Results The prevalence of megabacteria in the two colonies was significantly (P < 0.001) different. Overall the prevalence of megabacteria adjusted for colony differences was significantly higher (P < 0.025) in males compared to females. Age was not an influencing factor. After the initial survey, the prevalence in the offspring did not significantly (P > 0.05) decrease in the following two annual breeding seasons but by inference it did significantly decrease after amphotericin B treatment.
Conclusion The practice of culling most birds with more megabacteria in faeces and discriminating against positive birds when selecting birds for breeding or culling birds on show quality does not decrease megabacteria prevalence in the offspring. However, a reduction in prevalence does occur with administration of amphotericin B. Birds may have amphotericin B-resistant organisms and these birds need to be identified and culled. 相似文献
Design A monitoring study over several years.
Sample population Two budgerigar ( Melopsittacus undulatus ) colonies with over 300 birds each.
Procedure The prevalence of megabacteria in the faeces in two budgerigar breeding colonies, colony 1 and 2, was determined by faecal examination of each bird. Following an initial survey (1990), most of the birds that were scored 2+ or more were culled and a management practice was implemented to discriminate against positive birds. Consecutive yearly surveys (1991, 1992) were conducted on the young birds bred in these colonies. The prevalence of megabacteria in colony 2 was also evaluated in 1994 and 1996 after all the birds were treated with amphotericin B administered in drinking water.
Results The prevalence of megabacteria in the two colonies was significantly (P < 0.001) different. Overall the prevalence of megabacteria adjusted for colony differences was significantly higher (P < 0.025) in males compared to females. Age was not an influencing factor. After the initial survey, the prevalence in the offspring did not significantly (P > 0.05) decrease in the following two annual breeding seasons but by inference it did significantly decrease after amphotericin B treatment.
Conclusion The practice of culling most birds with more megabacteria in faeces and discriminating against positive birds when selecting birds for breeding or culling birds on show quality does not decrease megabacteria prevalence in the offspring. However, a reduction in prevalence does occur with administration of amphotericin B. Birds may have amphotericin B-resistant organisms and these birds need to be identified and culled. 相似文献
80.
文章根据高职院校的学风管理现状,提出了一些针对性的改善意见,包括突出学生思想品德教育、完善学风管理体系、协调各部门的工作等。 相似文献