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61.
随着市场的开放 ,经济的发展 ,我国畜禽生产持续高速增长 ,畜禽产品市场丰富 ,大大改善了人民的生活。在发展的同时 ,由于畜禽饲养量大增 ,导致饲料需求大幅增加 ,部分养殖户及饲料厂为了片面追求自身利益 ,在饲料中任意添加药物或使用违禁药物 ,从而造成严重的畜禽产品药物残留问题 ,给人民群众的身体健康造成极大的危害 ,肉食品安全的问题已经成为当今社会备受关注及具有较大影响的问题。为此 ,如何做好肉食品安全的管理工作 ,不仅涉及到广大人民的利益 ,也是我国畜牧业适应国际需求、参与市场竞争的必然选择。要真正做好这项工作 ,应抓好…  相似文献   
62.
Diversity of the ovine DQA2 gene   总被引:6,自引:0,他引:6  
Variation in the ovine DQA2 gene was investigated in approximately 2,000 sheep from six breeds. Fragments of DNA containing the ovine DQA2 exon 2 were amplified using PCR. Single-strand conformational polymorphism analysis and DNA sequence analysis were employed to detect genetic variation. Twenty-three nucleic acid sequences, encoding 22 DQA2 amino acid sequences, were identified. This increases the number of alleles identified from 10 to 23. In some cases, three or four unique sequences were isolated from individual sheep, suggesting that these DQA2 sequences may represent two loci. Phylogenetic tree analysis revealed that 5 of these 23 sequences were more closely related to cattle DQA3 or DQA4 sequences than to other sheep DQA2 sequences. These sequences clustered together and were called DQA2-like to differentiate them from other DQA2 sequences. There was no evidence of DQA5-like sequences in sheep. Information theory-based analysis indicated that some of the DQA2-like sequences had low information content at splice sites, suggesting that these alleles may have low functional activity. Allelic lineages were observed not only at the DQA2 locus, but also at the DQA2-like locus, supporting the trans-species mode of evolution of MHC genes. Comparison of the allelic sequences suggests that polymorphism seems to have arisen largely by point mutation and gene conversion, and a recent gene conversion event seems to have occurred between the DQA2 and DQA2-like loci. The high level of sequence polymorphism detected and varied number of loci demonstrate the extensive diversity of the ovine DQA2 gene.  相似文献   
63.
记者:公安部警犬技术学校被业界喻为中国警犬技术人才培养的摇篮,作为校长,请您介绍一下学校在办学方面有哪些特色?南会林:我校经历了几十年的办学实践,已经形成了培养优秀的警犬技术专业人才与训练优良警犬相结合的鲜明特色.  相似文献   
64.
阅读提示:"6.26"国际禁毒日前后,媒体有关缉毒犬的报道让读者领略了这一神秘武器的风采。不少读者向本刊反映,很想进一步了解中国缉毒犬训练使用的幕后故事,为飨读者,本刊专门采写了下文。  相似文献   
65.
中国狄斯瓦螨(Varroa destructor,大蜂螨)研究进展   总被引:4,自引:1,他引:4  
狄斯瓦螨(Varroa destructor Anderson & Trueman 2000,通称“大蜂螨”)是对世界养蜂业威胁最大的蜜蜂病虫害。2000年重新命名之前,它一直被称为雅氏瓦螨(Varroa jacobsoni Oudemans1904)。2000年初,澳大利亚安德森(Denis L.Anderson)对采集自亚洲各地东方蜜蜂(蜂螨原始寄主)和世界各地西方蜜蜂的大量大蜂螨样本进行线粒体(mtDNA)测序的综合研究。结果表明:原被归入雅氏瓦螨的东方蜜蜂寄生螨,应划分为2个种,一个是新界定的雅氏瓦螨,主要分布在印尼和马来西亚,已发现9个基因型;另一个是新定名的狄斯瓦螨,分布于亚洲大陆的东方蜜蜂和世界各地的西方蜜蜂,已发现11个基因型。  相似文献   
66.
Understanding the utilisation patterns of milk assists in designing appropriate dairy development schemes in rural communities. The objective of the study was to determine milk utilisation patterns in different smallholder farming systems in the Eastern Cape Province of South Africa. Data were collected through the administration of recording sheets to 130 randomly selected households in Alice, Fort Beaufort and Queenstown districts. Amounts of milk produced per household ranged from 9 to 21 l per household per day. Milk consumption/household/day was similar among the three districts. Milk consumption in the early lactation doubled the amount consumed in late lactation (P < 0.05). Milk in the communal areas was largely utilised as fresh or sour milk. Fresh milk was mostly used in tea/coffee or to make porridge for children. Sour milk was consumed with thick boiled maize meal. Fort Beaufort (10.2 ± 1.37 l/day) had the highest sour milk sales whilst Queenstown had the highest fresh milk sales (9.7 ± 5.57 l/day). It was concluded that quantities of milk consumed or sold as fresh or sour were generally low and varied across smallholder farming systems.  相似文献   
67.
Nematode infections are a serious constraint to pig production, especially where free range pig keeping is practiced. This study investigated the epidemiology of nematodes in free range pigs in Busia District, Kenya. Three hundred and six pigs from 135 farms were sampled for faeces that were analysed for nematode eggs per gram (EPG) of faeces using the McMaster technique. The nematode eggs were also identified to genus and species based on morphology. A questionnaire on risk factors was also administered to the pig owners. The overall prevalence and mean nematode EPG were 84.2% and 2,355, respectively. The nematode eggs were identified as those belonging to Oesophagostomum spp. (75%), Strongyloides ransomi (37%), Ascaris suum (18%), Metastrongylus spp. (11%), Trichuris suis (7%) and Physocephalus sexalatus (3%). The prevalence of nematodes was positively correlated (p < 0.05) with the amount of rainfall in the division of the pigs' origin (all nematodes except S. ransomi). The prevalence of nematodes was also associated with the age of the pigs. A lower burden of nematodes was associated (p < 0.05) with a history of deworming (A. suum) and the provision of night housing (S. ransomi and Metastrongylus spp.). In conclusion, this study has provided information on nematode infections and the associated risk factors for free range pigs in Busia District, which can be used when implementing integrated control measures.  相似文献   
68.
小肽营养素对奶牛泌乳性能的影响   总被引:31,自引:0,他引:31  
试验选择泌乳期中国荷斯坦奶牛32头,随机分为4组,A组(对照组)为基础精料日粮组;B、C、D组分别为基础精料日粮 0.1%、0.3%、0.5%小肽营养素。正试期28d。结果表明,添加0.1%、0.3%、0.5%小肽营养素后,奶牛头日平均产奶量分别提高1.67kg(6.38%)(P<0.05)、1.75kg(6.69%)(P<0.05)和1.64kg(6.27%)(P<0.05)。添加小肽营养素后,乳蛋白和乳脂率均有所提高,其趋势随小肽营养素添加量的增加而提高。添加0.1%、0.3%、0.5%小肽营养素后,奶牛头日净增效益3.52元、3.40元、2.86元。综合生产性能和经济效益,以添加0.1%-0.3%小肽营养素为适宜。  相似文献   
69.
影响饲料制粒的因素及其控制方法分析   总被引:4,自引:0,他引:4  
影响制粒的因素很多,有制粒机自身性能、待制粒原料理化性质、生产操作和工艺条件等。本文从饲料组分、物料理化性质、配方组成、压模和压辊等几个方面作了简要阐述,为提高饲料制粒效率,保证制粒质量提供参考。  相似文献   
70.
[目的]掌握安徽省规模猪场高致病性蓝耳病的感染状况和免疫抗体水平。[方法]采用抗体阻断ELISA、荧光RT-PCR方法检测了24个猪场的588份血清样本和28个场点的790份组织样品。[结果]高致病性蓝耳病个体抗体免疫合格率为78.1%,群体免疫合格率为75.0%;中型猪场的平均免疫抗体合格率为87.1%、小型猪场为63.9%。高致病性蓝耳病病毒核酸个体阳性率为28.7%,群体阳性率为75.0%;中型猪场、小型猪场和生猪屠宰场的高致病性蓝耳病病毒核酸个体阳性率分别为41.7%、19.5%和6%。[结论]2015年安徽省规模猪场的高致病性蓝耳病抗体免疫合格率较高,但存在带毒现象,建议加强疫病的免疫和综合防控。  相似文献   
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