| molecular epidemiology of subgroup c avian pneumoviruses isolated in the united states and comparison with subgroup a and b viruses. | the avian pneumovirus (apv) outbreak in the united states is concentrated in the north-central region, particularly in minnesota, where more outbreaks in commercial turkeys occur in the spring (april to may) and autumn (october to december). comparison of the nucleotide and amino acid sequences of nucleoprotein (n), phosphoprotein (p), matrix (m), fusion (f), and second matrix (m2) genes of 15 u.s. apv strains isolated between 1996 and 1999 revealed between 89 and 94% nucleotide sequence identit ... | 2002 | 11980943 |
| a single subtype of avian pneumovirus circulates among minnesota turkey flocks. | the recent emergence of avian pneumovirus (apv) infection among us turkey flocks has resulted in a major economic threat to the turkey industry. in order to elucidate the molecular epidemiology of apv, comparative sequence analysis of the fusion (f) protein gene of apv was performed for 3 cell culture-adapted isolates and 10 apv positive clinical samples recovered from us turkey flocks. relatively modest levels of nucleotide and amino acid sequence divergence were identified, suggesting the prev ... | 2002 | 12296387 |
| isolation of avian pneumovirus from an outbreak of respiratory illness in minnesota turkeys. | antibodies to avian pneumovirus (apv) were first detected in minnesota turkeys in 1997. virus isolation was attempted on 32 samples (28 tracheal swabs, 4 pools of trachea and turbinates) that were positive for apv by reverse transcriptase polymerase chain reaction (rt-pcr). the cell cultures used were chicken embryo fibroblast (cef), vero cells, and qt-35 cells. five virus isolates were obtained from these samples, and the identity of the isolates was confirmed by rt-pcr. four isolates were obta ... | 2000 | 10730950 |
| susceptibility of ducks to avian pneumovirus of turkey origin. | to determine the susceptibility of ducks to avian pneumovirus (apv) of turkey origin. | 2001 | 11453499 |
| avian pneumovirus (apv) rna from wild and sentinel birds in the united states has genetic homology with rna from apv isolates from domestic turkeys. | nasal turbinates or swabs were collected from wild ducks, geese, owls, sparrows, swallows, and starlings and from sentinel ducks placed next to turkey farms experiencing avian pneumovirus (apv) infections and were analyzed for apv genome and infectious particles. apv rna was detected in samples examined from geese, sparrows, and starlings. apv rna and antibodies were also detected in two different groups of sentinel ducks. infectious apv was recovered from sentinel duck samples. the apv m gene i ... | 2000 | 11060113 |
| specific detection of avian pneumovirus (apv) us isolates by rt-pcr. | this report details the development of an rt-pcr assay for the specific detection of us isolates of avian pneumovirus (apv). of the several primer pairs tested, two sets of primers derived from the matrix gene of apv were able to specifically detect the viral rna of apv. the nucleotide sequence comparison of the pcr products of apv isolates from minnesota suggested that these viruses were closely related to the colorado strain of apv, but were distinct from subtypes a and b european isolates of ... | 2000 | 10948996 |
| avian pneumovirus infection in minnesota turkeys: experimental reproduction of the disease. | avian pneumovirus (apv) is an emerging viral respiratory disease agent of turkeys in minnesota. clinical signs of apv infection include open mouth breathing, ocular and nasal discharge, and swelling of infraorbital sinuses. the virus spreads rapidly among flocks of susceptible turkeys and is associated with increased mortality rates. a flock of 11-wk-old turkeys experienced a respiratory problem characterized by coughing, sneezing, swollen sinuses, and nasal discharge. the reverse transcriptase- ... | 2000 | 10737667 |
| experimental and serologic observations on avian pneumovirus (apv/turkey/colorado/97) infection in turkeys. | an avian pneumovirus (apv) was isolated from commercial turkeys in colorado (apv/colorado) showing clinical signs of a respiratory disease. the results of virus neutralization and indirect fluorescent antibody tests showed that the apv/colorado was partially related to apv subgroup a but was unrelated to apv subgroup b. turkeys experimentally inoculated with the apv/colorado were observed for signs, lesions, seroconversion, and virus shedding. thirty-six 7-wk-old turkeys were distributed into th ... | 2000 | 10737640 |
| seroprevalence of avian pneumovirus in minnesota turkeys. | avian pneumovirus (apv) causes respiratory tract infection in turkeys and was first seen in the united states in colorado in late 1996. in early 1997, the disease was recognized in minnesota and caused estimated losses of up to 15 million dollars per year. this virus has not been reported in the other turkey producing states. we here report the seroprevalence of apv in minnesota from august 1998 to july 2002. the average rate of seroprevalence has been 36.3% (range = 14.2%-64.8%). a seasonal bia ... | 2003 | 14562899 |
| characterization of avian metapneumoviruses isolated in the usa. | avian pneumovirus (apv; officially known as turkey rhinotracheitis virus) is an emergent pathogen of birds in the usa that results in upper respiratory tract disease in turkeys. six years after the first outbreak in the usa, the disease continues to ravage turkey flocks, primarily in the state of minnesota. from 1997 to 2000, the industry recorded losses estimated at 15 million us dollars per annum. researchers have developed sensitive diagnostic techniques, including the enzyme-linked immunosor ... | 2002 | 12665110 |
| experimental and field evaluation of a live vaccine against avian pneumovirus. | the attenuation of an avian pneumovirus (apv) isolate (apv/mn/turkey/1-a/97) by 63 serial passages in cell culture (seven in chicken embryo fibroblasts and 56 in vero cells) and its evaluation as a live attenuated vaccine in turkey poults is described. the birds were vaccinated with two different doses of attenuated virus (10(4.5) median tissue culture infectious dose (tcid(50))/ml and 10(2.5) tcid(50) /ml) at 2 weeks of age, and were challenged 2 weeks later with virulent apv. no clinical signs ... | 2002 | 12396339 |
| pathogenesis of avian pneumovirus infection in turkeys. | avian pneumovirus (apv) is the cause of a respiratory disease of turkeys characterized by coughing, ocular and nasal discharge, and swelling of the infraorbital sinuses. sixty turkey poults were reared in isolation conditions. at 3 weeks of age, serum samples were collected and determined to be free of antibodies against apv, avian influenza, hemorrhagic enteritis, newcastle disease, mycoplasma gallisepticum, mycoplasma synoviae, mycoplasma meleagridis, ornithobacterium rhinotracheale, and borde ... | 2002 | 12014494 |