| the occurrence of avian influenza a subtype h6n2 in commercial layer flocks in southern california (2000-02): clinicopathologic findings. | between february 2000 and february 2002, the california animal health and food safety laboratory system diagnosed 26 cases of low-pathogenic h6n2 avian influenza from 12 commercial egg-laying farms. the most common gross and histologic lesions observed in infected chickens were fibrinous yolk peritonitis, salpingitis, oophoritis, and nephritis. edema of the mesentery of the oviduct and pale, swollen kidneys were also observed. mortality in infected flocks ranged from 0.25% to 3%, and egg product ... | 2003 | 14575145 |
| multiple genotypes of nonpathogenic h6n2 influenza viruses isolated from chickens in california. | from february 2000 through september 2001, a limited number of h6n2 influenza viruses were isolated from chickens in california. this report describes the genetic characterization of nine of these h6n2 viruses. all of the viruses analyzed had phylogenetically similar hemagglutinin (ha) and neuraminidase molecules that suggested the viruses shared a recent common ancestor. the analysis of the ha sequence of these viruses with all available h6 viruses from different hosts and locations showed that ... | 2003 | 14575084 |
| reassortment and interspecies transmission of north american h6n2 influenza viruses. | h6n2 influenza viruses were isolated from california chickens in 2000 and 2001. here we report the characterization of these h6n2 viruses, one of the few descriptions of non-h5, non-h7 subtype influenza viruses in this host. the h6n2 viruses were nonpathogenic in experimentally infected chickens and could be divided into three genotypes. all three genotypes of virus had similar surface glycoproteins and all contained an 18 amino acid deletion in the neuraminidase, a characteristic of other chick ... | 2002 | 12033764 |
| persistence of highly pathogenic and low pathogenic avian influenza viruses in footbaths and poultry manure. | a questionnaire was designed in order to gather information about bedding material and footbath preparation and maintenance in different productive units across the state of california.this information was used to plan two experiments. in the first experiment, we tested the effectiveness of footbaths in inactivating highly pathogenic (hp) and low pathogenic (lp) avian influenza viruses (aivs) on rubber boots. surprisingly, quaternary ammonia- and quaternary ammonia + glutaraldehyde-based footbat ... | 2017 | 28301246 |
| field detection of avian influenza virus in wild birds: evaluation of a portable rrt-pcr system and freeze-dried reagents. | wild birds have been implicated in the spread of highly pathogenic avian influenza (hpaiv) of the h5n1 subtype, prompting surveillance along migratory flyways. sampling of wild birds is often conducted in remote regions, but results are often delayed because of limited local analytical capabilities, difficulties with sample transportation and permitting, or problems keeping samples cold in the field. in response to these challenges, the performance of a portable real-time, reverse transcriptase- ... | 2010 | 20206650 |
| an evaluation of transmission routes for low pathogenicity avian influenza virus among chickens sold in live bird markets. | many theories about the modes of avian influenza virus (aiv) transmission have been proposed, but few have been quantified, and none within a flock or live bird market (lbm) setting where birds are often kept in stacked cages. we describe a novel experimental design and the results collected for the purpose of estimating transmission rates specific to the potential modes of aiv transmission within an lbm. chickens of the strains and ages found in california lbms were inoculated with low pathogen ... | 2009 | 19747706 |
| low-pathogenicity avian influenza virus (h6n2) in chickens in california, 2000-02. | during 2000, 2001, and january 2002, avian influenza virus was isolated from chickens from 12 different locations in california. all the isolates were typed as h6n2 and determined to be of low pathogenicity for chickens. nine of the isolates came from commercial layer flocks; one from a backyard flock; one from a mixed age flock, where ducks and squabs were also present; and one from a primary broiler breeder. although a drop in egg production and increased mortality were among the disease signs ... | 2003 | 14575080 |
| a flock-tailored early warning system for low pathogenic avian influenza (lpai) in commercial egg laying flocks. | the aim of this study was to develop and evaluate an early warning system (ews) for commercial egg laying flocks to detect the subtle mortality and egg production changes that characterize low pathogenic avian influenza virus (lpaiv) infections. an ews will create an alert when the recommended 'trigger point' is reached or exceeded. previously used ewss are based on fixed alert levels, while the proposed ews customizes the alert level to each flock. while a fixed approach may be valid for highly ... | 2009 | 19767114 |
| prevalence of low pathogenicity avian influenza virus during 2005 in two u.s. live bird market systems. | oropharyngeal and cloacal swabs were collected from poultry sold in two live bird market (lbm) systems to estimate the prevalence of low pathogenicity avian influenza virus (lpaiv) shedding during the summer and fall of 2005. random sampling was conducted in three lbms in minnesota where 50 birds were sampled twice weekly for 4 wk, and in three lbms in a california marketing system. a stratified systematic sampling method was used to collect samples from southern california lbms, where lpaiv was ... | 2011 | 21793439 |