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991.

Background

Swine influenza is an infectious acute respiratory disease of pigs caused by influenza A virus. We investigated the time of entry of swine influenza into the Finnish pig population. We also describe the molecular detection of two types of influenza A (H1N1) viruses in porcine samples submitted in 2009 and 2010.This retrospective study was based on three categories of samples: blood samples collected for disease monitoring from pigs at major slaughterhouses from 2007 to 2009; blood samples from pigs in farms with a special health status taken in 2008 and 2009; and diagnostic blood samples from pigs in farms with clinical signs of respiratory disease in 2008 and 2009. The blood samples were tested for influenza A antibodies with an antibody ELISA. Positive samples were further analyzed for H1N1, H3N2, and H1N2 antibodies with a hemagglutination inhibition test. Diagnostic samples for virus detection were subjected to influenza A M-gene-specific real-time RT-PCR and to pandemic influenza A H1N1-specific real-time RT-PCR. Positive samples were further analyzed with RT-PCRs designed for this purpose, and the PCR products were sequenced and sequences analyzed phylogenetically.

Results

In the blood samples from pigs in special health class farms producing replacement animals and in diagnostic blood samples, the first serologically positive samples originated from the period July–August 2008. In samples collected for disease monitoring, < 0.1%, 0% and 16% were positive for antibodies against influenza A H1N1 in the HI test in 2007, 2008, and 2009, respectively. Swine influenza A virus of avian-like H1N1 was first detected in diagnostic samples in February 2009. In 2009 and 2010, the avian-like H1N1 virus was detected on 12 and two farms, respectively. The pandemic H1N1 virus (A(H1N1)pdm09) was detected on one pig farm in 2009 and on two farms in 2010.

Conclusions

Based on our study, swine influenza of avian-like H1N1 virus was introduced into the Finnish pig population in 2008 and A(H1N1)pdm09 virus in 2009. The source of avian-like H1N1 infection could not be determined. Cases of pandemic H1N1 in pigs coincided with the period when the A(H1N1)pdm09 virus was spread in humans in Finland.  相似文献   
992.
AIM: To determine if migratory birds arriving in New Zealand in the Southern Hemisphere spring of 2004 were infected with the highly pathogenic avian influenza (AI) virus, H5N1.

METHODS: Cloacal and faecal samples were collected from migratory red knots following their arrival in New Zealand in October 2004. Two species of resident sympatric birds, wrybill and mallard duck, were sampled prior to, and following, the arrival of migratory birds.

RESULTS: No AI viruses were isolated from migratory or resident shorebirds. Non-pathogenic AI viruses were isolated from six resident mallard ducks, comprising the endemic subtypes H4 (n=2), H7 (non-pathogenic), H10, and H11 (n=2).

CONCLUSIONS: Highly pathogenic AI H5N1 virus was not detected in migratory shorebirds or sympatric water birds in the Firth of Thames, New Zealand, in 2004-2005, despite the possible proximity of migratory birds to outbreaks of the disease in East Asia in 2004.  相似文献   
993.
994.
The objective of this study was to investigate the effects of total dietary fiber level on nutrient digestibility and the relationship between apparent total tract digestibility of total dietary fiber, and soluble dietary fiber, insoluble dietary fiber and available energy. Sugar beet pulp was as the only fiber source. The experiment was designed as a 6 x 6 Latin square with an adaptation period of 7 d followed by a 5-d total collection of feces and urine. Feed intake tended to decrease (P =0.] O) as total dietary fiber level increased. The apparent total tract digestibility of dry matter, crude protein and gross energy decreased (P 〈0.0]) when total dietary fiber increased but the digestibility of soluble dietary fiber and insoluble dietary fiber increased (P 〈0.01). The digestible energy and metabolizable energy content of diets decreased (P 〈0.01) as the total dietary fiber increased.  相似文献   
995.
The correlation between IgY levels of the serum and the yolk has been well documented in wild and domestic birds. The levels of total yolk IgY can be an index of the general health status of birds and may contribute to breeding programs when fitness of the offspring is a concern. We measured the levels of total serum IgY and yolk IgY in three different breeds (White Leghorn, Silkie and Dongxiang blue-shell) using indirect ELISA, and found that there was a significantly positive correlation between the levels of total serum IgY and total yolk IgY in all three breeds (White Leghorn: r = 0.404, P 〈 0.001, n = 100; Silkie: r = 0.561, P 〈 0.001, n = 70; Dongxiang blue-shell: r = 0.619, P 〈 0.001, n = 30). We also measured the total serum IgY levels in the 3-day-old offspring hatched from the Silkie hens and results were significantly correlated for serum IgY levels (r = 0.535, P 〈 0.001, n = 70) and the yolk IgY levels (r = 0.481, P 〈 0.001, n = 70). The regression analysis showed simple linear regression between IgY levels in hen serum, yolk and offspring serum. Our results suggest that total IgY level could be used as an index for chicken fitness.  相似文献   
996.
We report a fall 2010 cluster of pandemic influenza A/H1N1 (pH1N1) infections in pet ferrets in Lehigh Valley region of Pennsylvania. The ferrets were associated with one pet shop. The influenza cluster occurred during a period when the existing human surveillance systems had identified little to no pH1N1 in humans in the Lehigh Valley, and there were no routine influenza surveillance systems for exotic pets. The index case was a 2.5‐month‐old neutered male ferret that was presented to a veterinary clinic with severe influenza‐like illness (ILI). In response to laboratory notification of a positive influenza test result, and upon request from the Pennsylvania Department of Health (PADOH), the Pennsylvania Department of Agriculture (PDA) conducted an investigation to identify other ill ferrets and to identify the source and extent of infection. PDA notified the PADOH of the pH1N1 infection in the ferrets, leading to enhanced human surveillance and the detection of pH1N1 human infections in the surrounding community. Five additional ferrets with ILI linked to the pet shop were identified. This simultaneous outbreak of ferret and human pH1N1 demonstrates the important link between animal health and public health and highlights the potential use of veterinary clinics for sentinel surveillance of diseases shared between animals and humans.  相似文献   
997.
[目的]对一种新的多酚氧化酶的提取方法与几种常用提取方法的综合效果进行比较.[方法]以苹果梨为研究对象,对匀浆法、匀浆吸附法、匀浆后丙酮抽提法、丙酮粉法、丙酮抽提后吸附法这5种多酚氧化酶提取方法所得酶液进行了多酚类化合物残余、总酶活及酶的稳定性的比较.同时,还对几种氨基酸对酪氨酸酶的抑制情况进行了检测.[结果]试验得出,以改进的丙酮抽提后吸附法所得酶液多酚残余少,总活力保持良好,为几种方法中最佳的提取方法.谷胱甘肽、谷氨酰胺、半胱氨酸、谷氨酸对酪氨酸酶的活力均有抑制作用,其IC50值分别为(0.48±0.028)、(0.59±0.032)、(0.37±0.016)和(1.87±0.087) mmol/L.[结论]研究可为多酚氧化酶的相关研究提供参考.  相似文献   
998.
[目的]研究不同来源金线莲中总黄酮含量差异。[方法]用微波萃取法对台湾、福建金线莲进行提取;以芦丁为对照品,采用紫外分光光度法测定提取物中总黄酮的含量。[结果]两处来源的金线莲总黄酮含量有差异,台湾的总黄酮含量较高,福建的总黄酮含量较低。[结论]台湾金线莲总黄酮含量比福建金线莲高,该研究结果对保证金线莲的质量和提高金线莲临床应用有着重要的意义。  相似文献   
999.
[目的]中药淫羊藿中总黄酮的含量测定。[方法]试验采用紫外分光光度法,以淫羊藿苷为对照品,以无水甲醇作空白对照,在270 nm波长处测定吸光度,计算总黄酮含量。[结果]淫羊藿苷浓度在1.68~10.08μg/ml范围内与吸光度的线性关系良好,R=0.999 4,总黄酮的平均回收率为100.36%,RSD为1.16%,淫羊藿中总黄酮的含量为(8.09±0.01)%。[结论]采用紫外分光光度法测定淫羊藿总黄酮的含量,操作快速,简便,准确。  相似文献   
1000.
[目的]研究海拔高度对短葶飞蓬总黄酮含量和酶活性的影响。[方法]通过对云南省不同海拔高度下短葶飞蓬野生植株总黄酮含量和苯丙氨酸解氨酶(PAL)及4-香豆酸辅酶A连接酶(4CL)活性的研究,探讨黄酮合成过程和海拔高度的关系。[结果]短葶飞蓬总黄酮含量和酶活性都与生长地海拔高度呈负相关关系,但相关程度不高,说明短葶飞蓬总黄酮合成过程可能还受其他原因的影响。[结论]海拔高度对短葶飞蓬总黄酮含量和酶活性有一定的影响。  相似文献   
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