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61.
随着现代生物技术在玉米深加工产业中的发展和应用,副产品的产量越来越大.玉米胚芽粕是一种以玉米纤维和蛋白质为主的高营养物质,生物效价PER值与WHO/FAO推荐值相近,近似于人奶和鸡蛋生物学价值,目前已用于育肥猪、反刍动物和家禽饲料添加.本研究对玉米胚芽粕的品质进行分析,以期将这一廉价的饲料资源进一步合理开发利用,取得更...  相似文献   
62.
The objective of this study was to compare the occurrence and the genotypes and species of Giardia duodenalis and Cryptosporidium spp. in beef and dairy cattle from farms in the Regional Municipality of Waterloo, Ontario, in an effort to determine the potential for zoonotic transmission from these animals. Pooled manure samples were collected from 45 dairy cattle farms and 30 beef cattle farms. The presence of Giardia cysts and Cryptosporidium oocysts was determined by immunofluorescence microscopy, while nested-PCR and DNA sequencing were used to determine genotypes and species. The overall farm prevalence was very high for both Giardia and Cryptosporidium, and was similar for dairy cattle farms (96 and 64%, respectively) and beef cattle farms (97 and 63%, respectively). However, on dairy cattle farms, G. duodenalis and Cryptosporidium spp. were detected in 44% and 6% of total pooled pen manure samples, respectively, with the occurrence of both parasites being generally higher in calves than in older animals. Most Giardia isolates were identified as either the host-adapted genotype G. duodenalis Assemblage E or the zoonotic Assemblage B. Cryptosporidium parvum and Cryptosporidium andersoni were the most frequently identified species in dairy cattle, while the non-zoonotic species Cryptosporidium ryanae and Cryptosporidium bovis were also found. On beef cattle farms, 72% and 27% of the total pooled pen manure samples were positive for Giardia and Cryptosporidium, respectively, with no obvious correlation with age. All Giardia isolates in beef cattle were identified as G. duodenalis Assemblage E, while all Cryptosporidium isolates were identified by sequence analysis as C. andersoni, although microscopic analyses, and subsequent restriction fragment length polymorphism analyses, indicated that other Cryptosporidium species were also present. The results of this study indicate that although Giardia and Cryptosporidium were identified in a higher overall percentage of the pooled beef cattle manure samples than in dairy cattle, firmly established zoonotic genotypes and species were much more common in dairy cattle than in beef cattle in this region. Dairy cattle, and especially dairy calves, may, therefore, pose a greater risk of infection to humans than beef cattle. However, these results may also provide evidence of potential zooanthroponotic transmission (human to animal).  相似文献   
63.
The present study examined sequence variability in a portion of the mitochondrial cytochrome c oxidase subunit 1 (pcox1) and NADH dehydrogenase subunits 4 and 5 (pnad4 and pnad5) among 39 isolates of Fasciola spp., from different hosts from China, Niger, France, the United States of America, and Spain; and their phylogenetic relationships were re-constructed. Intra-species sequence variations were 0.0-1.1% for pcox1, 0.0-2.7% for pnad4, and 0.0-3.3% for pnad5 for Fasciola hepatica; 0.0-1.8% for pcox1, 0.0-2.5% for pnad4, and 0.0-4.2% for pnad5 for Fasciola gigantica, and 0.0-0.9% for pcox1, 0.0-0.2% for pnad4, and 0.0-1.1% for pnad5 for the intermediate Fasciola form. Whereas, nucleotide differences were 2.1-2.7% for pcox1, 3.1-3.3% for pnad4, and 4.2-4.8% for pnad5 between F. hepatica and F. gigantica; were 1.3-1.5% for pcox1, 2.1-2.9% for pnad4, 3.1-3.4% for pnad5 between F. hepatica and the intermediate form; and were 0.9-1.1% for pcox1, 1.4-1.8% for pnad4, 2.2-2.4% for pnad5 between F. gigantica and the intermediate form. Phylogenetic analysis based on the combined sequences of pcox1, pnad4 and pnad5 revealed distinct groupings of isolates of F. hepatica, F. gigantica, or the intermediate Fasciola form irrespective of their origin, demonstrating the usefulness of the mtDNA sequences for the delineation of Fasciola species, and reinforcing the genetic evidence for the existence of the intermediate Fasciola form.  相似文献   
64.
据世界动物卫生组织(OIE)和世界口蹄疫参考实验室(WRLFMD)样品检测报告,2018年全球共有50多个国家或地区报告发生口蹄疫疫情或检测到口蹄疫病毒。在亚洲、非洲,口蹄疫继续呈地方性或暴发流行,在欧洲(如俄罗斯和土耳其)及南美洲(哥伦比亚)的部分国家呈散发性流行。本文介绍了2018年全球口蹄疫发生情况,分析总结了全球口蹄疫流行特点,简述了全球防控进展,同时结合我国口蹄疫流行情况,对我国口蹄疫防控提出了相关建议。  相似文献   
65.
畜禽注水肉的卫生检验与卫生处理   总被引:1,自引:0,他引:1  
注水肉系指不法经营者无视国家的屠宰法规和食品卫生法规 ,对畜 (牛、猪、兔等 )、禽 (鸡、鸭 )等在宰前或宰后人为地采用某种手段器械(注射器、皮管、压力泵 )通过畜禽口腔、食道、肛门直肠、动脉血管、皮下等部位注射入一定量的水分 ,以此增加畜禽重量 ,使胴体、肌肉、内脏的含水量剧增 ,达到饱和状态。近几年来 ,畜禽注水肉多见于牛肉、猪肉、鸡鸭肉 ,尤其在农贸集市非常普遍 ,已引起广大消费者和有关部门的关注。1畜禽注水的途径与方法1.1宰前活体注水灌食强行固定猪体灌水姿势 ,用皮管塞入口腔或肛门注入水 ,注水量可占体重的20%…  相似文献   
66.
人工牧草热量指标的研究   总被引:4,自引:0,他引:4  
  相似文献   
67.
通过在不同日龄对海兰褐蛋鸡进行禽流感(H9)灭活疫苗的免疫,探讨禽流感灭活疫苗的免疫间隔期。结果表明,开产以后不管防疫2次、3次、4次禽流感灭活疫苗,抗体水平均在6log2以上,且鸡的日龄越大,免疫次数越少,免疫抗体持续期越长。因此,建议从育成到鸡群淘汰的饲养全程中,四次时机恰当、搭配合理的禽流感(H9)疫苗免疫基本上能使得95%以上产蛋期抗体维持于7log2以上。  相似文献   
68.
OBJECTIVE: To radiographically evaluate the Zurich cementless total hip (ZCTH) cup and correlate lucency with clinical signs of implant instability, time since surgery, and implant generation, using zonal analysis. STUDY DESIGN: Retrospective study. ANIMALS: Client-owned dogs (n = 53). METHODS: Radiographs of dogs that had ZCTH arthroplasty (>1 year) were evaluated using zonal analysis, for lucency surrounding the cup-bone interface (number of zones, length, area). Dogs were examined for clinical signs of implant instability (lameness, hip pain). Lucency was correlated with lameness, time after surgery, and implant generation. RESULTS: Radiographs of 68 implants (18 generation I, 50 generation II) were evaluated. Eight dogs were lame (11.8%). Dogs with lameness were more likely to have lucency in > or =2 zones of analysis (per view), have >2 times the average curvilinear length of lucency, and have >4 times the average area of lucency surrounding the implant compared with non-lame dogs. A weak relationship was observed between time after surgery and implant generation; however, there was no relationship between time after surgery and lucency. CONCLUSIONS: Dogs with lameness after ZCTH arthroplasty were more likely to have lucency at the cup-bone interface. Lucency was better evaluated by radiographic projection than zonal analysis. Temporal progression of lucency was weakly correlated with implant generation. CLINICAL RELEVANCE: Dogs with lucency in > or =2 zones of analysis should be evaluated more frequently for clinical signs of implant loosening. Further investigation of serial radiographs after ZCTH arthroplasty is warranted.  相似文献   
69.
OBJECTIVE: To describe a percutaneously controlled static hydraulic urethral sphincter (SHUS) and evaluate urodynamic effects of the SHUS in canine cadavers. SAMPLE POPULATION: Cadavers of 6 adult female dogs. PROCEDURE: Cadavers were obtained immediately after dogs were euthanatized. Baseline maximal urethral closure pressure (MUCP) and cystourethral leak point pressure (CLPP) were measured by use of a urethral pressure profilometer. An SHUS system was constructed by use of a silicone vascular occluder and subcutaneous infusion port. The SHUS system was then placed around the pelvic urethra in each cadaver. Measurements of MUCP and CLPP were repeated after varying occlusion of the SHUS (0%, 25%, and 50% occlusion). Baseline MUCP and CLPP values were compared with values obtained at 0%, 25%, and 50% occlusion of the SHUS by use of repeated-measures ANOVA. RESULTS: Mean +/- SD MUCP for canine cadavers was 7 +/- 1.3 cm H2O at baseline, which increased to 127 +/- 53 cm H2O after 50% occlusion of the SHUS. Mean CLPP was 11 +/- 8.6 cm H2O at baseline, which increased to 73 +/- 38 cm H2O after 50% occlusion of the SHUS. Mean MUCP and CLPP were significantly associated with the amount of occlusion. CONCLUSIONS AND CLINICAL RELEVANCE: The SHUS had positive effects on MUCP and CLPP in canine cadavers. Therefore, additional evaluation of the SHUS in live dogs is warranted.  相似文献   
70.
OBJECTIVE: To investigate the effects of acupuncture on neural activity detected by use of manganese-enhanced functional magnetic resonance imaging (fMRI) and elucidate the relationship between somatic acupoint stimulation and brain activation. ANIMALS: 40 New Zealand White rabbits. PROCEDURE: Manganese-enhanced fMRI was performed in anesthetized rabbits manipulated with electroacupuncture (EA) on Zusanli (ST-36) and Yanglingquan (GB-34) acupoints. Image acquisition was performed on a 1.5T superconductive clinical scanner with a circular polarized extremity coil. T1-weighted images were acquired sequentially as follows: baseline, after mannitol injection, after manganese infusion, and 5 and 20 minutes after initiation of EA. RESULTS: Changes in focal neural activity were detected by use of manganese-enhanced fMRI. Stimulation on Zusanli (ST-36) for 5 minutes resulted in activation of the hippocampus, whereas stimulation on Yanglingquan (GB-34) resulted in activation of the hypothalamus, insula, and motor cortex. Activation became less specific after 20 minutes of EA. Furthermore, stimulation on ipsilateral acupoints led to bilateral brain activation. CONCLUSIONS AND CLINICAL RELEVANCE: Each acupoint has a corresponding cerebral linkage, and stimulation on these points resulted in time-dependent neural activation. Understanding the linkage between peripheral acupoint stimulation and central neural pathways may provide a useful guide for clinical applications of acupuncture.  相似文献   
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