基于风险因素分析的布鲁氏菌病渐进式控制实践

动物疫病渐进式控制路径(Progressive control pathway,PCP)是国际组织推荐的疫病净化和无疫认证风险测量与管理技术。本研究利用PCP策略,基于布鲁氏菌病主要传播风险因素分析与控制,在陕西省榆林市开展了陕北白绒山羊市场价值链研究和风险管理经济学评估。结果表明:在相关假定风险因素中,外购混养饲养模式、随意丢弃流产物、产羔地不严格消毒、近1年内有羊只引进、生产区与生活区不分离、2011年以后新建养殖场等因素是该地布鲁氏菌病传播的主要风险因素(P≤0.05);该市羊只交易频繁,大批量引进以从辽宁营口、内蒙古乌审旗、陕西横山为主;榆林市的府谷、佳县、清涧、靖边、定边等县引进羊只较为频繁;该市羊只以本地销售为主,部分销往陕西西安,以及内蒙古、宁夏、山西等地;榆阳区、绥德县、神木县、子洲县形成的规模化羊只集散市场是榆林市羊只流通的重要环节,成为疫病传播风险控制的关键节点。针对上述主要风险因素,通过PCP策略中的风险管理实施,该市饲养羊只平均增加生产效益18.75元/只;按照全市年饲养量1 000万只羊估算,每年可增加经济收入1.875亿元。该研究为切实提高布鲁氏菌病防控技术水平,探索有效防控模式提供了参考。     

浅谈母猪低温不食症的原因与治疗

笔者在日常从事动物疾病诊治中经常碰到妊娠母猪低温不食症。本病是母猪低温症是一种因饲养管理不当,营养失调,体内产热不足或散热过多而引起母猪体温下降的一种临床综合症,患猪都表现为突然发病,体温降至35～37℃,食欲明显下降甚至废绝。如不及时治疗或治疗方法不当,往往造成母、仔猪共同死亡,较严重的影响了广大农户的经济效益。     

反思HPAI疫情频发探讨行业应对策略

自2003年12月26日至2005年11月14日,全世界共报告126人感染禽流感病例,其中64人死亡。2004年1月27日,我国首次公布确诊湖北鄂州、广西隆安等地发生高致病性禽流感(HPAI)疫情。2005年5月至11月30日,我国的青海、湖南、安徽、新疆等地又相继发生高致病性禽流感疫情30起,发生的疫情已得到较好的控制,确诊有3例人感染禽流感病例,其中2例死亡。近两年频发的高致病性禽流感疫情给我国家禽养殖业带来了严峻挑战。疫情发生后,家禽生产销售均普遍受阻。汉川广东温氏家禽有限公司是湖北省家禽养殖的龙头企业,年出栏肉鸡1000多万只,60%在湖北省内销售…     

鸡肉质鲜味特性相关基因的克隆及序列分析

本研究对泰和乌骨鸡、隐性白羽肉鸡腺苷琥珀酸裂解酶基因的cDNA进行了克隆,并对序列进行了分析,共发现有6处碱基突变249 G→A(TH)、717 C→G(TH)、985 A→G(TH)仅在泰和乌骨鸡中出现;992 T→C(RW)、1400 C→T(RW)仅在隐性白羽肉鸡中出现;而在泰和乌骨鸡和隐性白羽肉鸡中均检测到突变1179 A→C(TH,RW).其中985 A→G(TH)、1400C→T(RW)处突变导致两处氨基酸突变Thr→Ala(305)、Ala→Val(443),其它4处碱基突变均为同义突变.另外对几种脊椎动物Adsl基因核苷酸序列水平、蛋白质水平同源性进行了比较分析.     

Low expression of mitofusin 1 is associated with mitochondrial dysfunction and apoptosis in porcine somatic cell nuclear transfer embryos

Mitochondria are necessary for the transition from oocyte to embryo and for early embryonic development. Mitofusin 1 is the main mediator of mitochondrial fusion and homeostasis. We investigated Mitofusin 1 expression levels in porcine somatic cell nuclear transfer (SCNT) embryos. The rate of blastocyst formation in SCNT embryos was reduced significantly compared with that of parthenogenetic activation embryos. SCNT embryos showed significantly decreased Mitofusin 1 expression and mitochondrial membrane potential, while exhibiting increased reactive oxygen species and apoptosis. Mitochondrial functional changes were observed in the SCNT embryos and may be correlated with low levels of Mitofusin 1 to negatively affect development.     

Cryptosporidium scrofarum n. sp. (Apicomplexa: Cryptosporidiidae) in domestic pigs (Sus scrofa)

We describe the morphological, biological, and molecular characteristics of Cryptosporidium pig genotype II and propose the species name Cryptosporidium scrofarum n. sp. to reflect its prevalence in adult pigs worldwide. Oocysts of C. scrofarum are morphologically indistinguishable from C. parvum, measuring 4.81–5.96 μm (mean = 5.16) × 4.23–5.29 μm (mean = 4.83) with a length to width ratio of 1.07 ± 0.06 (n = 400). Oocysts of C. scrofarum obtained from a naturally infected pig were infectious for 8-week-old pigs but not 4-week-old pigs. The prepatent period in 8-week-old Cryptosporidium-naive pigs was 4–6 days and the patent period was longer than 30 days. The infection intensity of C. scrofarum in pigs was generally low, in the range 250–4000 oocysts per gram of feces. Infected pigs showed no clinical signs of cryptosporidiosis and no pathology was detected. Cryptosporidium scrofarum was not infectious for adult SCID mice, adult BALB/c mice, Mongolian gerbils (Meriones unguiculatus), southern multimammate mice (Mastomys coucha), yellow-necked mice (Apodemus flavicollis), or guinea pigs (Cavia porcellus). Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. scrofarum is genetically distinct from all known Cryptosporidium species.     

甘肃茵陈蒿超临界CO2萃取产物化学成分的差异性分析

采用超临界CO2萃取联合气相色谱-质谱法检测了茵陈蒿Artemisia capillaris萃取产物化学成分,并与水蒸气蒸馏法相比较。结果从超临界CO2萃取提取物成分中确定了76种化合物,从水蒸气蒸馏提取物成分中确定了48种化合物。其中长马鞭草烯酮含量分别为37.35%和26.68%,2种方法测得的成分有所差异。与传统水蒸气蒸馏法相比,采用超临界CO2法更能真实、全面地反映茵陈蒿的化学组分,实验为进一步研究利用茵陈蒿植物资源提供了科学依据。     

Unrecognized diversity in New Guinean crayfish species (Decapoda,Parastacidae): The evidence from molecular data

The phylogenetic relationships among imported ornamental crayfish belonging to the genus Cherax were inferred from a combined dataset of 3 mitochondrial genes (COI, 16S and 12S) and by comparison with available GenBank sequences of 14 Cherax species. Furthermore, the concordance of previously described species obtained from a wholesaler (Cherax boesemani, C. holthuisi and C. peknyi) with available GenBank sequences was verified based on COI with special respect to comparison with sequences assigned as Cherax species. Recently described species C. gherardiae, C. pulcher and C. subterigneus belong to the northern group of Cherax species. Comparison and analysis with other GenBank COI sequences show previously unreported diversity of New Guinean species, suggesting 5 putative new species. Surprisingly, species assigned to the subgenus Astaconephrops do not form a monophyletic clade; this subgenus should be reappraised relative to the purported typical morphological characteristic of the uncalcified patch on male chelae. Increasing importation of crayfish underscores the importance of accurate species identification. Use of basic molecular methods is a necessary requisite for documenting occurrence, abundance and population trends of target species. Consequently, it helps to support eventual conservation decision‐making by stakeholders.     

不同品系杜洛克后代商品猪胴体性状的比较分析

为研究不同品系杜洛克作为终端父本对其后代商品猪胴体性状的影响,选取214和108头分别由美系和加系杜洛克公猪配种、出生时间相近(±2 d)和体重相近(35±5 kg)的后代三元商品猪进行育肥饲养,结束饲养后开展屠宰试验,测定背膘厚度、眼肌厚度、瘦肉率和肋骨数.结果显示:加系杜洛克商品后代的背膘厚度、眼肌厚度显著(P<0...