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21.
Through the lens of the Health Belief Model and Protection Motivation Theory, we analyzed interviews of 36 agricultural advisors in Indiana and Nebraska to understand their appraisals of climate change risk, related decision making processes and subsequent risk management advice to producers. Most advisors interviewed accept that weather events are a risk for US Midwestern agriculture; however, they are more concerned about tangible threats such as crop prices. There is not much concern about climate change among agricultural advisors. Management practices that could help producers adapt to climate change were more likely to be recommended by conservation and Extension advisors, while financial and crop advisors focused more upon season-to-season decision making (e.g., hybrid seeds and crop insurance). We contend that the agricultural community should integrate long-term thinking as part of farm decision making processes and that agricultural advisors are in a prime position to influence producers. In the face of increasing extreme weather events, climatologists and advisors should work more closely to reach a shared understanding of the risks posed to agriculture by climate change.  相似文献   
22.
The pathogenicity of serotype 8 group I avian adenovirus (GIAAV) strains (TR630 and Saga97 strains) from inclusion body hepatitis (IBH) against cyclophosphamide (CY)-treated 3-wk-old specific-pathogen-free (SPF) chickens was examined. SPF chickens were inoculated intramuscularly with 10(7) plaque-forming units of viruses. Both strains from IBH could produce hydropericardium and mortality in CY-treated chickens as hydropericardium syndrome (HPS) that serotype 4 GIAAV strains cause, although they could not induce either hydropericardium or mortality in nontreated chickens. Histologically, hepatocytic necrosis with intranuclear inclusions, pancreatic acinar necrosis with intranuclear inclusions, and epicardial edema were seen in CY-treated chickens inoculated with GIAAV from IBH. Immunohistochemically, these inclusions were positive against GIAAV antigen. There were neither histologic lesions nor positive reactions against GIAAV antigen in nontreated chickens inoculated with GIAAV from IBH. From the present findings, pathogenic characteristics of IBH strains and HPS strains in the chickens were essentially the same.  相似文献   
23.
To understand the epidemiology of Avian paramyxovirus serotype-1 (APMV-1) in pigeons in Japan, phylogenetic analysis was comprehensively conducted based on partial fusion protein gene using isolate from the surveillance of this virus with previously known Japanese pigeon strains. This surveillance was conducted using feces obtained from domestic pigeons collected in 40 prefectures throughout Japan from June 2011 to March 2013. From a total of 1,021 samples, a single virus (APMV1/pigeon/Japan/Kanagawa/2013: JP/Kanagawa-pg/2013) was isolated. All Japanese pigeon APMV-1 strains were clustered into a single genetic lineage, which was termed VIb/1 by phylogenetic analysis based on the F gene including the sequence of the cleavage site. These APMV-1 strains were further subdivided into four subgroups identified over 4 separate timeframes: 1984–1995 (group 1), 1995–2000 (group 2), 2001–2007 (group 3) and the novel subgroup isolated in 2013 (group 4). Each subgroup has specific amino acid motifs at a cleavage site of the F protein, namely, 112GRQKR-F117(except for one strain), 112RRKKR-F117, 112RRQKR-F117 and 112RRQKR-F117, respectively. Our data suggest that Japanese APMV-1 strains from pigeons were diverse and reinforced the possibility that there were multiple introduction routes from foreign countries into Japan.  相似文献   
24.
Nine fowl adenoviruses (FAdVs) isolated from chickens with inclusion body hepatitis (IBH) in Japan from 2009 to 2010 were characterized serologically and genetically. These isolates were all neutralized by antisera against the SR-48 strain (FAdV-2). Phylogenetic analysis based on the part of the hexon gene that included the L1 region revealed that all isolates were almost identical except one isolate in 2009. This suggests a common ancestor for the FAdVs obtained from chickens with IBH in Japan in 2010.  相似文献   
25.
Radiation mutant 415-1, which is the first known diploid pollen-part self-compatible mutant of pears (Pyrus spp.), has a decreased ability to produce pollen. To determine whether the self-compatibility trait is associated with this defect, we directly analyzed the genotypes of individual pollen grains by using polymerase chain reaction amplification of DNA from single pollen grains. We isolated single pollen grains from 415-1 and succeeded in genotyping the S-RNase gene and three simple sequence repeat (SSR) markers in linkage group 17. Out of 173 individual pollen grains, 28 (16 %) were S-heteroallelic. These pollen grains had two alleles each of the S-RNase gene and of two linked SSR loci, all on a duplicated chromosomal segment, but only one allele of a non-duplicated locus farther away on the same chromosome. The segregation ratio of each marker in the pollen from 415-1 was approximately the same as that observed in outcross progeny. This suggests that the decrease in frequency of pollen with the duplicated S-haplotype occurred during meiosis or pollen formation, but that the probability of fertilization by S-heteroallelic pollen is equal to that of single-allelic pollen. However, the partial sterility in 415-1 can also be attributed to one or more unidentified lethal mutations unlinked to the duplicated segment encompassing the S-haplotype. Single-pollen genotyping can be used in a variety of applications in genetic research because in cases where all pollen genotypes are proportionately represented in the progeny, segregation ratios can be obtained without producing the next generation.  相似文献   
26.
To evaluate the possibility of virus transmission through feathers of call ducks, we performed two experiments, intranasal infection study and transmission study, using the Japanese H5N1 highly pathogenic avian influenza virus (HPAIV) A/chicken/Yamaguchi/7/2004 (Ck/Yama/7/04). In Experiment 1, 1-day-old, 2-wk-old, and 4-wk-old birds were inoculated intranasally with Ck/Yama/7/04. Birds in all age groups exhibited necrosis and/or viral antigens in the feather epithelium. Nonpurulent encephalitis and focal necrosis of the pancreas and heart also were common to inoculated birds. In Experiment 2, nine 2-wk-old birds that were orally inoculated with feathers of an infected call duck exhibited the nonpurulent encephalitis, necrosis of the feather epithelium, and focal necrosis of the pancreas and heart, accompanied by viral antigens. These lesions were similar to those in intranasal infection. Some birds were positive for the virus isolation from cloacal swabs and hemagglutination inhibition antibody. The infection was confirmed in seven of nine birds. This study confirmed that the Japanese HPAIV can replicate in the feather epithelium, causing necrosis in call ducks through the natural infection route. It also suggests that feathers of call ducks infected with Ck/Yama/7/04 can be a potential source of infection for unaffected birds in nature.  相似文献   
27.
An experimental infection study was performed using pigeons reared for racing or meat production in Japan and clade 2.2 and 2.3.2 isolates of H5N1 highly pathogenic avian influenza virus to evaluate the possible role of pigeons in virus transmission to poultry. In experiment 1, when 20 pigeons were intranasally inoculated with high or low viral doses, no inoculated pigeon exhibited clinical signs for 14 days. Drinking water and almost all swab samples were negative for virus isolation. Virus isolation was positive in 3 oral swab samples from 2 pigeons from day 2 through 4 postinoculation, but viral titers of positive samples were extremely low. Immunohistochemical analysis for virus detection was negative in all tissue samples. Along with seroconversion in a limited number of pigeons postinoculation, these results suggest that pigeons have limited susceptibility to the virus used for experimental infection. In experiment 2, when uninoculated chickens were housed with virus-inoculated pigeons, all pigeons and contact chickens survived for 14 days without exhibiting any clinical signs. According to serological analysis, the chickens did not exhibit seroconversion after close contact with inoculated pigeons. Our data suggest that the risk posed by pigeons with respect to the transmission of the H5N1 highly pathogenic avian influenza virus to poultry would be less than that for other susceptible avian species.  相似文献   
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The mortality and pathology caused by serotype 4 adenovirus, isolated from chickens with hydropericardium syndrome (HPS) in Japan, was investigated in specific-pathogen-free (SPF) chickens. One-day-old to 15-mo-old SPF chickens were inoculated intramuscularly, orally, and intranasally with liver homogenates from HPS chickens or isolated serotype 4 adenovirus. There were no clinical signs before death. The mortality rate in all groups of 1-day-old chicks was 100%, irrespective of the inoculum or inoculation route. Four-week-old chickens inoculated with liver homogenate also had a 100% mortality rate. Five-week-old chickens inoculated with cell culture of HPS adenovirus had a 40% mortality rate. The mortality rates of 7-mo-old hens inoculated with liver homogenates intramuscularly and orally were 75% and 25%, respectively. In 15-mo-old hens inoculated with liver homogenates intramuscularly, the mortality rate was 70%. Gross lesions were hydropericardium and swelling and congestion of the liver with occasional petechial hemorrhages. Histologically, the liver had diffuse or multifocal hepatic necrosis and hemorrhage with intranuclear inclusion bodies noted within hepatocytes. In the spleen, macrophages containing erythrocytes and yellow pigment were prominent in the red pulp. In the lung, a moderate diffuse macrophage infiltration was noted throughout the lung parenchyma, and these macrophages contained yellow pigment. In the pancreas of the chicks inoculated at 1 day old, there was multifocal necrosis of glands with intranuclear inclusion bodies. Intranuclear inclusion bodies were seen also in the gizzard, proventriculus, duodenum, cecum, kidney, and lung of the chicks inoculated at 1 day old. Immunohistochemically, the intranuclear inclusion bodies of various organs showed positive reactions against group I avian adenovirus. Adenovirus was recovered from the liver of chickens with HPS. This study indicates that HPS adenovirus is able to reproduce HPS lesions and mortality in SPF chicks and even adult chickens and that it is a highly pathogenic strain.  相似文献   
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