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71.
A biological attack on livestock or poultry could result in the loss of valuable animals, costs related to the containment of outbreaks and the disposal of carcasses, lost trade and other economic effects involving suppliers, transporters, distributors and restaurants; however, it is not possible to secure all livestock, and livestock are much less well guarded than human targets. Thus, the vulnerability of the livestock industry to the introduction of biological agents varies for the following reasons: (i) the majority of lethal and contagious biological agents are environmentally resilient, endemic in foreign countries and harmless to humans, making it easier for terrorists to acquire, handle and deploy these pathogens, (ii) with animals concentrated in fewer production facilities and frequently transported between these facilities, a single pathogen introduction could cause widespread infection and (iii) the extent of human travel around the globe makes it difficult to exclude exotic animal diseases as possible biological agents. Historically, many governments have developed and planned to use biological agents for direct attacks on livestock or poultry. In the past, developed nations have actively developed biological weapons to target animals. The potential spectrum of bioterrorism ranges from isolated acts against individuals by individuals to tactical and strategic military attacks and state‐sponsored international terrorism intended to cause mass casualties in animals, humans or both. This review provides an overview of the past development and use of biological weapons and describes potential future attacks. 相似文献
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猪繁殖障碍性主要传染病的血清流行病学研究 总被引:2,自引:0,他引:2
对采自云南省楚雄州10县市22个规模猪场及107户农户的803份猪血清、642份临床无异常的种猪抗凝全血、84头繁殖障碍母猪血清及4头乳猪脏器,应用胶乳凝集试验(LAT)、猪伪狂犬病gE抗体鉴别酶联免疫吸咐试验(ELISA)、多方法酶联免疫吸咐试验、虎红平板凝集试验及试管凝集试验、间接血凝试验(HIA)、细菌学检验、流行病学调查等方法,对PR、PPV、PRRS、PCV-2、CSF、JE、布病、衣原体病共8种病同步进行血清学(猪瘟病原学)调查,结果感染率分别为30.39%、21.05%、3.11%、59.40%、1.71%、24.53%、0.25%和10.71%。流行病学调查结果,繁殖障碍发病场占调查场的68.18%,各场母猪繁殖障碍发病率在75.00%-0之间,农户散养母猪在20.00%-0之间。 相似文献
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Bio—G除臭剂对蛋鸡舍内氨气及产蛋性能的影响 总被引:2,自引:0,他引:2
在面积相等,饲养密度相近的2栋蛋鸡舍内连续15d喷洒Bio-G除臭剂,每天1次,每次5L,结果表明,喷洒Bio-G后,鸡舍氨气含量明显下降,但对蛋鸡产蛋性能无明显影响。 相似文献
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B. Fuerst‐Waltl B. Rinnhofer C. Fuerst C. Winckler 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2010,127(2):113-118
Cross‐sucking and intersucking are considered abnormal behaviours in cattle and constitute a common problem in dairy farming. Cross‐sucking in calves is defined as sucking any body parts of another calf whereas intersucking in heifers and cows is defined as sucking the udder or udder area. The aim of this study was to determine the genetic variability for abnormal sucking behaviour by estimating genetic parameters and examining individual differences between sires with large progeny groups. By means of a questionnaire, cattle breeders in the federal state Lower Austria were requested to identify all currently kept animals which are known of either inter‐ or cross‐sucking (both defined as the same binary trait ‘sucking’ with 0 and 1 referring to the absence and presence of this abnormal behaviour) or allowing sucking (also treated as a binary trait, scored as 1 if an animal was known of allowing herd mates to suck and 0 otherwise). Records of 1222 farms and 13 332 dual purpose Simmental females aged between 21 and 700 days were investigated applying a linear animal model with fixed herd × year × season and random genetic animal effect and a threshold sire model with the herd × year × season effect being treated as random. In total, 8.6% and 4.1% of all calves/heifers were observed sucking and allowing sucking, respectively. Heritabilities of 0.040 ± 0.014 and 0.007 ± 0.006 (linear animal model) and 0.116 ± 0.041 and 0.026 ± 0.024 (threshold model) were found for the traits sucking and allowing sucking, respectively. Breeding values were estimated applying the same models for the trait sucking. Taking all 254 sires into account, the Pearson and Spearman correlation coefficients between breeding values estimated by linear animal and sire threshold model were 0.86 and 0.80. Thus, little difference was observed between the two methods. 相似文献