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Coronaviruses in avian species – review with focus on epidemiology and diagnosis in wild birds
2018
Miłek, Justyna | Blicharz-Domańska, Katarzyna
Coronaviruses (CoVs) are a large group of enveloped viruses with a single-strand RNA genome, which continuously circulate in mammals and birds and pose a threat to livestock, companion animals, and humans. CoVs harboured by avian species are classified to the genera gamma- and deltacoronaviruses. Within the gamma-CoVs the main representative is avian coronavirus, a taxonomic name which includes the highly contagious infectious bronchitis viruses (IBVs) in chickens and similar viruses infecting other domestic birds such as turkeys, guinea fowls, or quails. Additionally, IBVs have been detected in healthy wild birds, demonstrating that they may act as the vector between domestic and free-living birds. Moreover, CoVs other than IBVs, are identified in wild birds, which suggests that wild birds play a key role in the epidemiology of other gammaCoVs and deltaCoVs. Development of molecular techniques has significantly improved knowledge of the prevalence of CoVs in avian species. The methods adopted in monitoring studies of CoVs in different avian species are mainly based on detection of conservative regions within the viral replicase, nucleocapsid genes, and 3’UTR or 5’UTR. The purpose of this review is to summarise recent discoveries in the areas of epidemiology and diagnosis of CoVs in avian species and to understand the role of wild birds in the virus distribution.
اظهر المزيد [+] اقل [-]Occurrence of reovirus (ARV) infections in poultry flocks in Poland in 2010–2017
2018
Czekaj, Hanna | Kozdruń, Wojciech | Styś-Fijoł, Natalia | Niczyporuk, Jowita Samanta | Piekarska, Karolina
Introduction: Avian reovirus (ARV) infections in poultry populations are reported worldwide. The reovirus belongs to the genus Orthoreovirus, family Reoviridae. The aim of the study was to evaluate the incidence of ARV infections in the poultry population based on diagnostic tests performed in 2010–2017. Material and Methods: Samples of the liver and spleen were collected from sick birds suspected of ARV infection and sent for diagnostics. Isolation was performed in 5–7-day-old SPF chicken embryos infected into the yolk sac with homogenates of internal organs of sick birds. Four primer pairs were used to detect the σNS, σC, σA, and µA ARV RNA gene fragments. A nested PCR was used for the detection of the σNS and σC genes. Results: In 2010–2017, ARV infection was found in birds from 81 flocks of broiler chickens and/or layers, 8 flocks of slaughter turkeys, and in 4 hatchery embryos at 17–20 days of incubation. The primers used in RT-PCR and nested PCR did not allow effective detection of ARV RNA in all virus-positive samples. Conclusion: The problem of ARV infections in the poultry population in Poland still persist. The primers used for various ARV segments in RT-PCR and nested PCR did not allow effective detection of RNA in the visceral organs of sick birds. The presented results confirm the necessity of using classical diagnostic methods (isolation in chicken embryos, AGID).
اظهر المزيد [+] اقل [-]An overview of highly pathogenic avian influenza (H5N1) outbreak cases in Kelantan, west Malaysia in year 2017
2018
Wan Norulhuda W. A. W. | Tariq J.
Malaysia has experienced four waves of H5N1 outbreak but no humandeaths were recorded which is in 2004, 2006, 2007 and latest outbreak in 2017 at Kelantan. The objective of this paper is tocollect, analyse and summarise the data of HPAI cases from the outbreak from 1 March to 22 June 2017. A total of 1,634 cases, 8,544 samples were received at the Registration Unit and Virology Section, Regional Veterinary Laboratory in Kota Bharu (RVLKB) for diagnosis and surveillance of H5N1 during this period. The samples received were pooled organs and intestines from post-mortem (41 cases) and cloaca swabs in tryptose phosphate buffer from surveillance (1,593 cases), which were sent to RVL, Kota Bharu and Veterinary Research Institute, Ipoh, Perak (VRI). They were processed and diagnosed using quantitative real-time reverse transcriptase PCR (RT qPCR) technique to detect and subtyping of the virus. Total positive cases for H5N1 were 53 out of 1,634 with 18 diagnostic cases and 35 surveillance cases. All positive cases during outbreak were detected from 43 locations from six districts of Kota Bharu, Bachok, Pasir Puteh, Pasir Mas, Tumpat and Tanah Merah, with 19 locations in Kota Bharu which is thehighest affected by H5N1, seven locations in Bachok, four in Pasir Putih, six in PasirMas, six in Tumpat and one in Tanah Merah. Many factors could have led to the acute spread of the virus between the districts like chicken smuggling, legal and illegal poultry trade, migration of infected wild birds and others. Understanding the source of outbreak and how it spread is important to control, eradicate and prevent the spread of the disease as it is zoonotic and infects human.
اظهر المزيد [+] اقل [-]A case report on the 2017 highly pathogenic avian influenza (H5N1) outbreak in poultry in Kelantan
2018
Zubaidah, M. A. | Tariq J. | Nur Raihan M. A. | Abd Halim H.
Highly pathogenic avian influenza (HPAI) is caused by influenza virus A from the family Orthomyxoviridae. It is a severe, systemic disease with high mortality in avians. The mortality can be as high as 100% in a few days. On 28 February 2017, HPAI virus of H5N1 subtype was confirmed in village chickens at Kampung Pulau Tebu, Batu 5, Tunjong Kota Bharu, Kelantan. It wasthe second outbreak of HPAI in Kelantan after the first reported case at Tumpat Kelantan on 17 August 2004. Most of the dead poultry showed similar clinical signs of sudden death with high mortality, cyanosis and oedema of head, comb, wattle and snood as well as red discolouration of shanks and feet. Post-mortem was performed on dead poultry and there were generalised haemorrhages of all internal organs, congested mesenteric blood vessels andpinpoint haemorrhages on proventriculus. Histopathological examination revealed generalised pulmonary haemorrhages with moderate interstitial pneumonia, generalised hepatic haemorrhages and hepatitis with multifocal area of hepatic necrosis, generalised haemorrhagic myocarditis and generalised haemorrhagicnephritis. Confirmation test was performed using RT-PCR and viral isolation at Veterinary Research Institute, Ipoh. 36 foci wereaffected involving five districts (Kota Bharu, Tumpat, Bachok, Pasir Mas and Tanah Merah) causing depopulation of 56,953 poultryand 17,531 eggs. Surveillance and control measures were taken by Department of Veterinary Services to contain the disease from spreading to other areas.
اظهر المزيد [+] اقل [-]Comparison of growth rate of salmonella for antigen production
2018
Zarrahimah Z. | Dahlia H. | Harnita E. | Muhammad Marwan I. | Chee, W. K. | Nor Liyana M. R.
Salmonella stained antigen has been widely used in Malaysia for detection of Salmonella infection in poultry. Growth phase of four Salmonella enterica serovar Pullorum (SP 9-25, SP 14/11, SP 690/79 and SP 7107/07) used in the antigen production were investigated based on colony enumeration and turbidity. This study aimed to determine the growth curve and the difference between S. Pullorum isolates based on turbidity measurement and spread plate technique for optimisation towards biomass production of salmonella antigen using bioreactor. Current production of the antigen used conventional methods and the number of bacterial cells is low and with several other drawbacks. The isolates were cultured in nutrient broth, incubated aerobically with constant shake for 48 hours to determine the lag, exponential, stationary and the death phase of the bacteria. Turbidity of the bacterial cells was measured using spectrophotometer and the colony was counted using total plate count every four hours. Based on the colony forming unit per milliliter, SP 690/79 strain showed the fastest growth where this bacteria achieved its mid-exponential growth at 8 hours. This is followed by SP 14/11 where this strain demonstrated the mid-exponential growth at 12 hours. The other two strains (SP 9-25 and SP 7107-07) are the slowest growth where their mid-exponential growth was measured at 14 hours. However, SP 690/79also the fastest strain entering the death phase which demonstrates the difference growth of the S. Pullorum strains. This study demonstrates that each S. Pullorum strains multiplying and dying at different phase though in the same serovar.
اظهر المزيد [+] اقل [-]Effects of a nutrient-enriched water with and without poultry flavoring on water intake, urine specific gravity, and urine output in healthy domestic cats fed a dry kibble diet
2018
Zanghi, Brian M. | Wils-Plotz, Emma | DeGeer, Staci | Gardner, Cari L.
OBJECTIVE To investigate water intake and urine measures in healthy cats provided free-choice access to a nutrient-enriched water with (NWP) or without (NW) added poultry flavoring offered at 3 different volumes in addition to tap water (TW). ANIMALS 36 domestic shorthair cats. PROCEDURES Control group cats (n = 4) received dry food with TW ad libitum throughout the study. Cats of the NW and NWP groups (n = 16/group) received the same food with TW only (period 1; 7 days) followed by TW and the assigned treatment ad libitum at 1X, 1.5X, and 2X the volume of TW consumed in period 1 during periods 2 (17 days), 3 (10 days), and 4 (10 days), respectively. Liquid consumption, food intake, and total water intake (from all sources) were measured; urine collected over 48 hours in each period was measured, and urine specific gravity (USG) was determined. Data were analyzed with mixed-effects models. RESULTS TW and food calorie intake were similar among groups in period 1; TW consumption by control cats did not differ during the study. Liquid consumed by drinking increased 18%, 57%, and 96% for the NWP group in periods 2, 3, and 4, respectively, with increases of 25% and 44% for the NW group in periods 3 and 4, respectively, compared with period 1 values for the same groups. Increased urine output and decreased USG were significantly associated with period and treatment. CONCLUSIONS AND CLINICAL RELEVANCE Increasing the volumes of NW or NWP offered to healthy cats led to increased free liquid consumption and was associated with greater urine output and dilution as measured by USG. Studies are warranted to determine whether these treatments provide health benefits for cats in need of greater water consumption.
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