猪瘟活疫苗(脾淋源)污染外源性兔出血症病毒的检测与启示

在进行2批猪瘟活疫苗（脾淋源）效力检验时,出现效力检验家兔突然死亡现象,为了查明家兔死亡原因,采用无菌检验、支原体检验、血凝试验、兔体中和试验、酶联免疫吸附试验（ELISA）对疫苗或注苗后死亡家兔肝脏、脾脏混合病料进行了检测。结果显示,疫苗的无菌检验、支原体检验结果均为阴性;疫苗及注射疫苗死亡家兔肝脏、脾脏混合病料具有较低的血凝价,血凝试验结果均为可疑;在兔体中和试验中,中和组家兔2／2健康存活,未中和的疫苗对照组家兔2／2死亡;疫苗及注射疫苗死亡后家兔肝脏、脾脏混合病料的ELISA检测结果均为阳性。检测结果证实疫苗中含有兔出血症病毒（Rabbit Haemorrhagic Disease Virus,RHDV）。猪瘟活疫苗（脾淋源）污染RHDV的现象启示：应该加强猪瘟活疫苗（脾淋源）抗原制备过程的控制;同时有必要对猪瘟活疫苗（脾淋源）质量标准进行修订使之进一步补充完善。     

Characterization of the village goat production systems in the rural communities of the Eastern Cape,KwaZulu-Natal,Limpopo and North West Provinces of South Africa

Expansion of goat improvement programs requires exploration of the factors that influence the production system and breeding initiatives. Characterization of goat breeds or populations is crucial in providing information on prevalent goat types and their attributes and may suffice as a guideline on conservation, development, and selection for improved productivity. This study investigated the existing village goat production system and phenotypic diversity of the different village populations from four South African provinces. The study further investigated the use of phenotypic attributes to classify goats to breeds or populations. Data was collected from 142 households in 26 villages of the Eastern Cape (n?=?2 villages), KwaZulu-Natal (n?=?6 villages), Limpopo (n?=?13 villages), and North West (n?=?5 villages) provinces through a survey. Individual interviews and focus group discussions revealed that the mean goat herd size per household was least in Limpopo at 13.2?±?12.40 and highest in Eastern Cape (34.18?±?28.36). Flocks had more (p?<?0.05) adults than kids, and the distribution of breeding animals was biased towards does and less bucks. Goats were kept mainly for meat, for selling, and for ritual ceremonies. The goat production system was mainly scavenging. Goat health was a major challenge across households and villages. Qualitative traits such coat, horn, ears, and wattle characteristics were recorded for populations of village goats (n?=?319) and a feral Tankwa breed (n?=?50). The dominant coat pattern was plain (74.53%) with black as the most common coat color (31.98%). Across breeds, a majority (88.08%) of the goats had horns, and 7.59% had wattles while 56.64% had beard. Adult goats (<3 years; n?=?398) were further analyzed for five quantitative traits of chest girth, height, length, and pin bone and there were significant (p?<?0.05) breed differences in all. A stepwise discriminatory procedure was used to rank the quantitative traits according to their discriminatory power to separate breeds or populations. Significant traits were then subjected to canonical discriminant analysis for principle component analysis. Based on the quantitative traits, the Tankwa, Xhosa, and Tswana goats formed their own cluster separated from commercial meat type breeds and the Venda and Zulu ecotypes. The discriminant function analysis correctly classified 90.41% of the Zulu goats and 82.93% of the Xhosa village populations. None of the Savanna goats were correctly classified. The study demonstrated diversity in village goat populations and production systems, which would allow for within population selection in genetic improvement programs. The heterogeneity in the phenotypic traits in the village goats is reflective of the role of village production systems in the maintenance of animal diversity in local populations.     

Limited awareness of animal influenza prevention and control among Dai Lue smallholder farmers in Southwest China

Awareness of animal influenza and its prevention and control is important for ensuring livestock health, production and welfare. In China, a country stereotyped as a major source of emerging zoonotic infectious diseases, research on the public understanding of animal influenza is limited to the Han, the main ethnic group. The present qualitative study in Southwest China investigated awareness of animal influenza among the Dai, an ethnic minority. The participants (15 men and 10 women, ages 18–83) were smallholder farmers of pigs and poultry in rural areas of Jinghong, Xishuangbanna, Yunnan Province. A mixture of interviews and group discussions took place in homes and villages. The participants were asked about their knowledge of avian influenza (H7N9), swine influenza (H1N1), precautions taken to protect against influenza, procedures when animals were sick and perceived risk of animal influenza. The data were analysed following coding and thematic analysis. The findings demonstrated a limited understanding of animal health and welfare among participants. Specifically, they were largely unaware of animal influenza (H7N9, H1N1) including its causes, symptoms, prevention and treatment. The farmers were also uninformed of the risks they faced and unknowingly engaged in behaviours which increased direct or indirect exposure to infected animals, a risk factor for human infection. They also reported poor usage of veterinary services. In order to guarantee the health, welfare and production of their livestock, immediate action is needed to enable Dai smallholder farmers to prevent and respond to animal influenza effectively and timely.     

沼液浸种对黑麦草种子发芽的影响

为了研究沼液浸种对黑麦草种子发芽的影响,设置4个浓度沼液分别浸泡黑麦草种子,分析种子各项发芽指标的变化。结果表明:各处理均能正常发芽,黑麦草种子的发芽率和发芽势等4项发芽指标均随着浸种沼液浓度的增加呈现先上升后下降的趋势,以75%沼液浓度浸种效果最优,但沼液浸种对发芽率和发芽势的影响要高于苗高和根长。综合分析认为利用沼液浸泡黑麦草种子是提高其生产性能的有力措施,适宜在生产中推广利用。     

Temporal-spatial epidemiology of foot-and-mouth disease outbreaks in Mongolia, 2000 – 2002

Prior to 2000, foot-and-mouth disease (FMD) had not been observed in Mongolia since 1973; however, between April 2000 and July 2002, Mongolia reported 44 FMD outbreaks that affected cattle, sheep, goats, and camels. The objectives of this study were to describe the distributions of the 44 reported FMD outbreaks in Mongolia and to assess their spatial clustering and directions of movement. Official reports were collected to obtain the number and species of animals both affected and at risk, and the date and geographical coordinates of each outbreak. Significant global and local spatial clusters of reported FMD outbreaks were identified. Disease spread during the second epidemic moved 76° northeast and the spread of the disease during the third epidemic moved 110° northwest. FMD outbreaks were clustered intensely close to other FMD-positive counties. These findings can be used in the future to help plan prevention and control measures in high risk areas.     

动物、动物产品药物残留及应对措施

动物性食品中的药物残留量虽然很低,但对人体健康的潜在危害却甚为严重,对畜牧业生产影响巨大,而且影响深远,是国内外普遍关注的     

Accuracy of genomic prediction using different models and response variables in the Nordic Red cattle population

Breeding animals can be accurately evaluated using appropriate genomic prediction models, based on marker data and phenotype information. In this study, direct genomic values (DGV) were estimated for 16 traits of Nordic Total Merit (NTM) Index in Nordic Red cattle population using three models and two different response variables. The three models were as follows: a linear mixed model (GBLUP), a Bayesian variable selection model similar to BayesA (BayesA*) and a Bayesian least absolute shrinkage and selection operator model (Bayesian Lasso). The response variables were deregressed proofs (DRP) and conventional estimated breeding values (EBV). The reliability of genomic predictions was measured on bulls in the validation data set as the squared correlation between DGV and DRP divided by the reliability of DRP. Using DRP as response variable, the reliabilities of DGV among the 16 traits ranged from 0.151 to 0.569 (average 0.317) for GBLUP, from 0.152 to 0.576 (average 0.318) for BayesA* and from 0.150 to 0.570 (average 0.320) for Bayesian Lasso. Using EBV as response variable, the reliabilities ranged from 0.159 to 0.580 (average 0.322) for GBLUP, from 0.157 to 0.578 (average 0.319) for BayesA* and from 0.159 to 0.582 (average 0.325) for Bayesian Lasso. In summary, Bayesian Lasso performed slightly better than the other two models, and EBV performed slightly better than DRP as response variable, with regard to prediction reliability of DGV. However, these differences were not statistically significant. Moreover, using EBV as response variable would result in problems with the scale of the resulting DGV and potential problem due to double counting.     

Mapping B-cell linear epitopes of NS3 protein of bovine viral diarrhea virus

Bovine viral diarrhea virus (BVDV) is a member of the genus Pestivirus within the family Flaviviridae. NS3 is one of the immunodominance regions of the BVDV viral proteins. To identify the potential B-cell linear antigenic epitopes within BVDV NS3 region, serial overlapping truncations covering the whole region were expressed and purified, and screened by multistep of Western-blot. We found (₁VCKKITEHERCHVNI₁₅), (₂₀AFFGVMPRGTTPRAPVR₃₆), (₄₆RRGLETGWAYTHQGGI₆₁), (₂₈₁EGDMATGITYASYGYFC₂₉₇), (₄₂₆YSGEDPANLRVVTSQSPYVVVATNAIESGV₄₅₅) and (₄₈₁FIVTGLKRMAVTVGEQA₄₉₇) can be recognized by the BVDV infected bovine serum. These proteins have been confirmed by indirect enzyme-linked immunosorbent assay (I-ELISA). The results of this study might open new perspectives on the structure and antibody–antigen reaction of the non-structural proteins and may aid in the clinical application as well.     

果蔗不同器官在不同生育期的同工酶聚类相关分析

为了解过氧化物酶(POD)和酯酶(EST)同工酶在果蔗生长中的变化规律,本研究选择不同的取样时期和植株不同器官,对8个果蔗品种利用垂直平板聚丙烯酰胺电泳得出的叶片、根组织不同生育时期POD、EST同工酶酶谱进行聚类分析,并检测其相关性。结果表明：（1）不同品种间同工酶谱的遗传相似系数存在差异,特别是外引黑皮果蔗(Badila)与中国地方品种之间存在着一定的遗传差异;（2）不同生育时期叶片或根部的POD同工酶和EST同工酶酶谱的聚类图都存在着差异;（3）叶片中的POD、EST酶谱在各个生育时期均达到极显著相关。说明叶片是这两种酶基因表达的最重要活性部位,因此叶片可以作为同工酶分析较为稳定和适宜的采样部位。