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121.
Forty-two ewes had an intravenous catheter sewn in place in a prepared area over the jugular vein and beginning at 60 days of gestation received an infusion 3 times daily. The infusion consisted of sterile saline or sterile saline containing arginine. Twenty-six ewes in both control and treatment groups aborted between 81 days of gestation and term. Fetuses from 16 ewes that aborted were examined. Most were autolyzed or had early mummification. Macroscopic placentitis and noncollapsing lungs were noted. Large numbers of coagulase-positive Staphylococcus were isolated from fetal abomasal content, lungs, brains, or placentas. Histologically, suppurative placentitis with necrosis and pulmonary aspiration of meconium and amniotic debris often with suppurative bronchopneumonia were observed in abortuses. Four ewes euthanized and examined after abortion had suppurative endometritis. Three ewes had severe, chronic, jugular thrombophlebitis from which coagulase-positive Staphylococcus was isolated. The fourth ewe had mild phlebitis, and Staphylococcus aureus was isolated from both the catheter and the blood. Catheter-associated staphylococcal abortion was diagnosed. 相似文献
122.
Effects of finishing implants on heifer carcass characteristics and LM Warner-Bratzler shear force (WBSF) were investigated using commercially fed Continental x British heifers (n = 500). Heifers were blocked by initial BW (block 1, BW > or = 340 kg; block 2, BW < 340 kg) and assigned randomly to 12 treatments that utilized 0, 1, or 2 finishing implants to deliver cumulative dosages of trenbolone acetate (TBA) and estradiol 17-beta (E2) ranging from 0 to 400 mg of TBA and 0 to 40 mg of E2 during the finishing period. Heifers in blocks 1 and 2 were slaughtered after 135 and 149 d on feed, respectively. At these endpoints, the treatment groups did not differ (P > 0.05) in adjusted fat thickness or predicted percentage of empty body fat. Compared with a nonimplanted control, implanting heifers once during finishing increased (P = 0.025) HCW by an average of 7.9 kg without affecting the mean marbling score, the percentage of carcasses grading Choice and Prime, or LM WBSF values. Compared with the use of 1 implant, the use of 2 finishing implants resulted in an additional increase (P = 0.008) in HCW of 6.0 kg. Reimplanting also increased (P < 0.001) LM area, reduced (P = 0.024) the percentage of KPH, and improved (P = 0.004) mean yield grade. However, reimplanted heifers produced a lower (P = 0.044) percentage of carcasses grading Choice and Prime and LM steaks with greater (P < 0.05) WBSF values at all postmortem aging times compared with heifers that were implanted once. Among heifers receiving 2 implants, mean 14-d LM WBSF increased linearly (P < 0.05) as the cumulative, combined dosage of E2 plus TBA increased. Heifers implanted with a combination of E2 plus TBA had larger (P = 0.046) LM areas, lower (P = 0.004) mean marbling scores, and greater LM WBSF values after 3 d (P = 0.001), 7 d (P = 0.001), 14 d (P = 0.003), and 21 d (P = 0.045) of postmortem aging than did heifers implanted with TBA alone. Heifers that received combination implants containing both E2 and TBA also produced fewer (P = 0.005) carcasses with marbling scores of modest or greater compared with heifers that received single-ingredient implants containing TBA alone. Implant treatment effects on LM WBSF gradually diminished as the length of the postmortem aging period increased. Postmortem aging periods of 14 to 28 d were effective for mitigating the detrimental effects of mild or moderately aggressive heifer implant programs on the predicted consumer acceptability of LM steaks. 相似文献
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Epidemiology of H5N1 avian influenza 总被引:1,自引:0,他引:1
Yee KS Carpenter TE Cardona CJ 《Comparative immunology, microbiology and infectious diseases》2009,32(4):325-340
High pathogenic (HP) H5N1 avian influenza (AI) infection has been reported in domestic poultry, wildlife, and human populations since 1996. Risk of infection is associated with direct contact with infected birds. The mode of H5N1 spread from Asia to Europe, Africa and the Far East is unclear; risk factors such as legal and illegal domestic poultry and exotic bird trade, and migratory bird movements have been documented. Measures used to control disease such as culling, stamping out, cleaning and disinfection, and vaccination have not been successful in eradicating H5N1 in Asia, but have been effective in Europe. 相似文献
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试验性氟中毒对肉鸭肝细胞凋亡的影响 总被引:1,自引:0,他引:1
为研究肉鸭氟中毒与肝细胞凋亡的关系及其形态学改变,选用8日龄的天府肉鸭160只,随机分成4组,分别在常规饲料中添加0、350、450和550 mg/kg的氟化钠攻毒,攻毒后每隔8 d,每组扑杀5只,采用末端脱氧核苷酸转移酶 (TdT)介导的dUTP缺口末端标记法 (TUNEL)对试验性氟中毒肝组织标本进行处理和标记,光镜下观测24、40、56日龄肉鸭肝细胞凋亡的百分率和形态学改变。TUNEL检测结果显示,在肉鸭氟中毒模型中,DAB着色的阳性细胞呈凋亡细胞的典型形态特征;肝细胞凋亡的百分率较对照组明显升高。结果表明,肉鸭氟中毒时以肝细胞早期和中期凋亡为主,随着摄氟时间的延长和摄氟剂量的加大,肝细胞由凋亡逐渐发展为坏死。表明过量氟在体内毒性作用和肝细胞凋亡密切相关。 相似文献
129.
“互联网+”精准农业航空服务平台体系架构设计与实践 总被引:3,自引:0,他引:3
【目的】为农业航空植保作业服务商和终端农户提供沟通和服务的桥梁,推进农业航空标准的建立,推动科研院校的成果转化,对全国植保无人机实施跟踪和监管,促进农业航空市场规范,普及农业航空技术在精准农业中的应用,实现农药化肥施药零增长。【方法】利用"互联网+"的思维和方法,结合我国农业航空的发展状况与农业航空服务的特点,设计1套"互联网+"精准农业航空服务平台体系架构。采用大数据技术、云计算技术、移动应用技术以及HTML5等新一代信息技术,进行精准农业航空服务平台的底层架构设计、服务作业流程设计、用户界面设计以及数据库设计等。【结果】建立了精准农业航空服务的互联网综合服务平台,包含植保服务管理、作业效果评估管理、无人机检测管理、植保无人机监管、大数据应用等系统功能。它具有良好的平台特性、用户特性、大数据特性和扩展性。【结论】平台的体系架构能满足农业航空植保用户、植保服务商对植保作业服务简化操作的需求,同时实现了政府和有关部门对数据进行信息化有效管理的目的,并且通过数据分析与挖掘等技术手段提供多种增值服务,实现精准农业航空服务生态圈的有效良性循环,让农业航空更好地为我国农业现代化服务。 相似文献
130.
M Ugliano JB Dieval TE Siebert M Kwiatkowski O Aagaard S Vidal EJ Waters 《Journal of agricultural and food chemistry》2012,60(35):8561-8570
The evolution of different volatile sulfur compounds (VSCs) during bottle maturation of two Shiraz wines submitted to controlled oxygen exposure prior to bottling (through micro-oxygenation, MOX) and postbottling (through the closure) was investigated. H(2)S, methyl mercaptan (MeSH), and dimethyl sulfide (DMS) were found to increase during aging. Lower postbottling oxygen exposure, as obtained by different degrees of oxygen ingress through the closure, resulted in increased H(2)S and methyl mercaptan. In one wine MOX increased the concentration of H(2)S and methyl mercaptan during maturation. Dimethyl disulfide and DMS were not affected by any form of oxygen exposure. Overall, postbottling oxygen had a stronger influence than MOX on the evolution of VSCs. Data suggest that dimethyl disulfide was not a precursor to methyl mercaptan during bottle maturation. For the two wines studied, a consumption of oxygen of 5 mg/L over 12 months was the most effective oxygen exposure regimen to decrease accumulation of MeSH and H(2)S during bottle aging. 相似文献