oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Epidemiological aspects of astrovirus and coronavirus in poults in the South Eastern Region of Brazil
Silva, S.E.L. da;Bonetti, A.M.;Petrocelli, A.;Ferrari, H.F.;Luvizotto, M.C.R.;Cardoso, T.C.;
Brazilian Journal of Microbiology , 2009, DOI: 10.1590/S1517-83822009000200008
Abstract: a survey of turkey coronavirus (tcov) and astrovirus (tastv-2) prevalence was carried out from february to december during 2006 year in semiarid region of brazil, from a turkey producer area, localized in south eastern of brazil. to asses the risk factor related to clinical material, climatic condition and type of rt-pcr applied, cloacal swabs (cs), faeces, sera, bursa of fabricius (bf), thymus (th) and spleen (sp) and ileum-caeca region were collected from 30-day-old poults suffering of enteritis episode characterized as poult enteritis mortality syndrome (pems). the pems clinical features were characterized by watery to foamy faeces, light brown-yellow in colour and low mortality rate. meteorological data (rainfall and relative humidity) observed during along the study presented monthly average temperature ranging from 39.3 and 31.2oc, precipitation in rainy season from 40 to 270.3 mm/month, and no rain during dry season. simplex rt-pcr gave odds ratio (or) values suggesting that ileum-caeca region is at higher chance (or=1.9; p=0.9741) to have both viral rna than faeces (or=1.5; p=0.7319). however, multiplex rt-pcr showed 3.98 (p=0.89982) more chance to give positive results in faeces than cs at dry season. the major risk factors seem to be low rate of humidity and high temperatures at winter, probably responsible for spread, easily, the tcov and tastv-2 among the flocks. the positive results of both virus suggested that they can play an important role in enteric disorders, associated to low humidity and high temperatures frequently found in tropical countries.
Novel Coronavirus and Astrovirus in Delaware Bay Shorebirds  [PDF]
Kirsi S. Honkavuori, Thomas Briese, Scott Krauss, Maria D. Sanchez, Komal Jain, Stephen K. Hutchison, Robert G. Webster, W. Ian Lipkin
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0093395
Abstract: Background Wild birds are an important but to some extent under-studied reservoir for emerging pathogens. We used unbiased sequencing methods for virus discovery in shorebird samples from the Delaware Bay, USA; an important feeding ground for thousands of migratory birds. Findings Analysis of shorebird fecal samples indicated the presence of a novel astrovirus and coronavirus. A sanderling sample yielded sequences with distant homology to avian nephritis virus 1, an astrovirus associated with acute nephritis in poultry. A ruddy turnstone sample yielded sequences with homology to deltacoronaviruses. Conclusions Our findings highlight shorebirds as a virus reservoir and the need to closely monitor wild bird populations for the emergence of novel virus variants.
Coronavirus–associated enteritis in a quail farm  [cached]
Elena Circella,Vito Martella,Giordano Bruni,Eleonora Lorusso
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2007.326
Abstract: An enteric syndrome observed in semi-intensively reared quails is described. The affected birds showed depression, severe diarrhoea and dehydration. The mortality occurred particularly in young birds. At necropsy, the prominent lesion was catarrhal enteritis. Laboratory investigations demonstrated the presence of coronavirus in the gut of dead animals. No additional pathogens were detected. To our knowledge, this is the first evidence for the presence of CoVs in quail with enteritis.
Detection of Antibodies against Turkey Astrovirus in Humans  [PDF]
Victoria A. Meliopoulos, Ghazi Kayali, Andrew Burnham, Christine M. Oshansky, Paul G. Thomas, Gregory C. Gray, Melinda A. Beck, Stacey Schultz-Cherry
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0096934
Abstract: Astroviruses are a leading cause of gastroenteritis in mammals and birds worldwide. Although historically thought to be species-specific, increasing evidence suggests that astroviruses may cross species barriers. In this report, we used enzyme-linked immunosorbent assays to screen sera from three distinct human cohorts involved in influenza studies in Memphis, TN or Chapel Hill, NC, and Midwestern poultry abattoir workers for antibodies to turkey astrovirus type 2 (TAstV-2). Surprisingly, 26% of one cohort’s population was TAstV-2 positive as compared to 0 and 8.9% in the other cohorts. This cohort was composed of people with exposure to turkeys in the Midwestern United States including abattoir workers, turkey growers, and non-occupationally exposed participants. The odds of testing positive for antibodies against turkey astrovirus among abattoir workers were approximately 3 times higher than the other groups. These studies suggest that people with contact to turkeys can develop serological responses to turkey astrovirus. Further work is needed to determine if these exposures result in virus replication and/or clinical disease.
Effect of Chelated Calcium Proteinate Fed in the Maternal Diet of Turkey Breeders on Embryo Cardiac Physiology and Poult Quality  [PDF]
V. L. Christensen,J.L. Grimes,R.D. Rowland,D.T. Ort
International Journal of Poultry Science , 2006,
Abstract: Embryo and hatchling survival diminish as turkey breeder hens age. Recent data indicated that a chelated calcium proteinate (CCP) additive given to turkey breeder hens improved embryo survival as hens aged but did not affect shell thickness. We hypothesized that the mechanism by which this occurred may be by improved functional shell quality and its consequent effect on cardiac physiology. To test the hypothesis, CCP was supplemented to the diet of Large White turkey breeder hens for a 25 week egg production period and compared with controls without supplementation. Eggshell conductance, conductance constants, poult growth and cardiac physiology were measured at weeks 10, 18 and 25 of production. Because elevated temperatures increase heart rates and reduce heart weight and survival, half of the eggs was incubated at 37.9°C whereas the remaining eggs were incubated at 37.5°C. Embryos and poults from the CCP group exhibited increased heart weights and improved cardiac health. The hatching poults from CCP-fed hens also grew faster for the first 3 d of life. We conclude that CCP improves eggshell conductance, and the subsequent eggshell conductance constant (k) of eggs from turkey breeder hens. The change in k improved embryo cardiac health and poult BW after hatching.
Haemorrhagic enteritis seroconversion in turkey breeders: field observations  [cached]
Raffaella Ceruti,Marco Della Valentina,Luigi Gavazzi,Annalisa Venni
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2007.321
Abstract: Seroconversion to viral haemorrhagic enteritis (HE) was studied in seven flocks of turkey breeders (17.974 birds in total), after 20 weeks of the onset of egg production. They showed no clinical signs, and mortality rate was normal. However, the infection caused a drop in egg production lasting about five weeks (-2.32 eggs laid during this period), but had no effect on hatching parameters.
Severe enteritis in Italian Mediterranean buffalo calves associated with a novel bovine-like coronavirus
N. Decaro,M. Campolo,V. Mari,C. Desario
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2007.s2.854
Abstract: An outbreak of severe enteritis in Italian Mediterranean buffalo calves is reported, which was associated to infection by a novel bovine-like coronavirus (CoV). By conventional and real-time RT-PCR assays for bovine-like CoVs, the virus was demonstrated in the intestinal contents of two 20-day-old buffalo calves that died of a severe form of enteritis, as well as in the fecal specimens of additional 17 buffalo calves with diarrhea. Biological and genetic characterization showed that the bubaline strain can be considered as prototype of a novel group 2 CoV, namely bubaline CoV (BuCoV).
Effects of Diacetoxyscirpenol and Fusaric Acid on Poults: Individual and Combined Effects of Dietary Diacetoxyscirpenol and Fusaric Acid on Turkey Poult Performance  [PDF]
A.S. Fairchild,J.L. Grimes,J.K. Porter,W.J. Croom
International Journal of Poultry Science , 2005,
Abstract: Turkey poults were randomly placed in batteries and fed one of four dietary treatments: control (C); control plus 4ppm diacetoxyscirpenol (DAS); control plus 300 ppm (FA); and control plus 4ppm DAS and 300ppm FA (FD). There were 10 poults per pen with 6 replicate pens per treatment. Individual BW, BW gains (BWG) and feed consumption by pen was determined at d6, d12, and d18. Period and cumulative feed to gain was calculated. Mouth lesions were scored for treatments at d18. On d18 poults were euthanized for determination of organ weights and jejunal histomorphometrics. FA had no effect on BW or BWG at any period compared to C. Poults fed FD had reduced BW and BWG compared to C, while poults fed DAS had lower BW than all treatments at every period. Poults fed FA or C had better feed to gain (P<0.05) than poults fed DAS or FD at d6. There were no differences among the treatments at d12 or d18. Poults fed FA had significantly lower relative intestine wt than poults fed other diets, and significantly higher relative bursa wt at d18 when compared to poults fed DAS or FD. DAS, FA and FD altered intestinal architecture. Poults fed DAS or FD had higher mouth lesion scores than poults fed FA or C, but mouth lesion scores in DAS and FD poults were not different from each other. Dietary DAS resulted in decreased poult performance, while dietary FA had little or no effect. Fusaric acid fed in combination with DAS resulted in some protective effect towards DAS.
First report of bovine rotavirus and bovine coronavirus seroprevalance in goats in Turkey  [PDF]
Gumusova Okur S.,Yazici Z.,Albayrak H.,?akiroglu D.
Veterinarski Glasnik , 2007, DOI: 10.2298/vetgl0702075g
Abstract: In this study, bovine coronavirus (BCV) and bovine rotavirus (BRV) seroprevalances were detected by ELISA in 107 goat blood serum samples obtained from five different provinces of Northern Turkey. The results of the study reflected 41.12% and 82.24% seropositivity against BCV and BRV, respectively, in the goat sera. BCV seroprevalance in mature goats is determined for the first time with this study. Furthermore, this is the first statement of BRV and BCV seroprevalances in the mature goat population in Turkey.
Metagenomic analysis of the turkey gut RNA virus community
J Michael Day, Linda L Ballard, Mary V Duke, Brian E Scheffler, Laszlo Zsak
Virology Journal , 2010, DOI: 10.1186/1743-422x-7-313
Abstract: Enteric disease syndromes such as Poult Enteritis Complex (PEC) in young turkeys and Runting-Stunting Syndrome (RSS) in chickens are a continual economic burden for poultry producers. The only reliable method to reproduce the clinical signs of these syndromes in experimental birds is oral inoculation with crude preparations of intestinal contents from naturally infected birds. Further, the full spectrum of the field signs observed associated with these syndromes is difficult to reproduce experimentally with isolated viruses [1,2]. Numerous viruses are known to be circulating in turkey flocks in the United States, with recent research efforts targeting RNA viruses such as the turkey astroviruses, novel turkey-origin reovirus, and avian rotavirus, and DNA viruses such as the recently described turkey parvovirus [3-6]. However, there remains a possibility that an unidentified virus or combination of viruses may play a role in poultry enteric disease. Despite the isolation and characterization of many of these suspect viruses, the etiology of the poultry enteric disease syndromes remains elusive, and many enteric viruses can be detected in otherwise healthy turkey and chicken flocks [3,4]. Regional and national enteric virus surveys have revealed the ongoing presence of avian reoviruses, rotaviruses and astroviruses in turkey and chicken flocks, with combinations of viruses often present in the poultry gut [3,4]. A non-biased, comprehensive approach to virus discovery that would not require viral cultivation would reveal a great deal about the complex viral community in the turkey gut. Further, a community-based understanding of the viruses in the poultry gut will be an invaluable asset in ongoing studies of the enteric disease syndromes and would be welcome knowledge to poultry producers who rely upon efficient conversion of feed in the gut to produce an economically important commodity. A recent study utilizing a sequence-independent molecular screen of virus particle
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.