细化搜索
结果 1-4 的 4
Preparation of Turkey Pox Vaccine in SPF Eggs
2018
Olfat E. Nakhla | Manal Awad | Soad M. Soliman | A. Michael
An identified local virulent Egyptian strain of turkey pox virus (TPV) was attenuated on specific pathogen free (SPF) embryonated chicken eggs (ECE) for production of specific turkey pox vaccine. Forty serial passages of the virus were applied on the chorioallantoic membrane (CAM) of SPF ECE, so titration of the serial passages were undergone in which the highest titres (107.0, 107.1 and 107.1 EID50/ml) were recorded for the passages 30, 35 and 40, respectively. The pathogenicity of the 10th, 20th, 30th and 40th passages were tested by inoculation in susceptible turkeys. The passage of 30th and 40th passages produced the most acceptable post vaccinal reaction (pvr) beside giving the highest virus titre of the attenuated passages. The selected field dose which gave only takes (swelling of the skin) at the site of injection in susceptible turkeys and withstood challenge with the virulent turkey pox virus one month later was 104.0 EID50/ml. The prepared vaccine tested for sterility, safety and potency tests and proved to be potent for the vaccinated turkeys which resisted the challenge for 9 months post vaccination. Antibody levels in the serum of vaccinated turkeys were estimated by serum neutralization test, where neutralizing antibodies expressed as neutralizing index were appeared from the 1st week (1.0 NI) and reached its peak on the 3rd week (2.2 NI) post vaccination
显示更多 [+] 显示较少 [-]Inactivated H5 antigens of H5N8 protect chickens from lethal infections by the highly pathogenic H5N8 and H5N6 avian influenza viruses
2018
Jin, Myongha | Jang, Yunyueng | Seo, Taehyun | Seo, Sang Heui
Introduction: Highly pathogenic Asian H5-subtype avian influenza viruses have been found in poultry and wild birds worldwide since they were first detected in southern China in 1996. Extensive control efforts have not eradicated them. Vaccination prevents such viruses infecting poultry and reduces the number lost to compulsory slaughter. The study showed the efficacy of inactivated H5 vaccine from the H5N8 virus against highly pathogenic H5N8 and H5N6 avian influenza viruses in chickens. Material and Methods: Reverse genetics constructed an H5 vaccine virus using the HA gene of the 2014 H5N8 avian influenza virus and the rest of the genes from A/PR/8/34 (H1N1). The vaccine viruses were grown in fertilised eggs, partially purified through a sucrose gradient, and inactivated with formalin. Chickens were immunised i.m. with 1 µg of oil-adjuvanted inactivated H5 antigens. Results: Single dose H5 vaccine recipients were completely protected from lethal infections by homologous H5N8 avian influenza virus and shed no virus from the respiratory or intestinal tracts but were not protected from lethal infections by heterologous H5N6. When chickens were immunised with two doses and challenged with homologous H5N8 or heterologous H5N6, all survived and shed no virus. Conclusion: Our results indicate that two-dose immunisations of chickens with H5 antigens with oil adjuvant are needed to provide broad protection against different highly pathogenic H5 avian influenza viruses.
显示更多 [+] 显示较少 [-]Contamination of soils with Toxocara eggs in several playgrounds of Ipoh, Perak
2018
Erwanas A. I. | Zary S. | Nurulaini R. | Adnan M. | Debbra M. | Azizah D. | Azima Laili H.
Toxocariasis is an important cosmopolitan zoonotic disease mainlycaused by Toxocara spp., a type of soil transmitted helminth (STH) on cats and dogs. In this study, 80 soil samples were taken from four public playgrounds and six neighbourhood playgrounds in Ipoh, Perak between October and December 2016 to determine the status of soil contamination with the eggs of Toxocara spp. Results showed that 32.5% from the total soil samples were positive with Toxocara spp. eggs. Overall, five out of ten of the sampling sites were contaminated with Toxocara spp. eggs. Besides that, the relationship between the soil condition and the occurrence of the Toxocara spp. eggs in soils were also investigated. The findings showed that increase of moisture and pH of the soils contributed to the increase of contaminationwith Toxocara spp. eggs. Sandy soils were found significantly contaminated with the eggs of Toxocara spp. compared to theother types of soil. Therefore, appropriate preventive measures such as treatment of soil, regular monitoring and deworming of dogs and cats as well as awareness programmes to the public are important.
显示更多 [+] 显示较少 [-]A survey of parasite pathogens in stray dogs from Pudu pasar and Chow Kit area of Kuala Lumpur
2018
Jamnah O. | Chandrawathani P. | Mariappan C. | Ramlan M. | Premaalatha B. | Losheni S. | Zaini C. M. | Banumathy G.
Stray dogs are carriers of several zoonotic diseases such as leishmaniasis and canine monocytic ehrlichiosis (CME) as a result of poor nutrition, low hygienic conditions and lack of veterinary care. Thus, the Veterinary Research Institute (VRI) conducted a survey to determine the parasite pathogens such as blood protozoans, gastrointestinal parasites and ectoparasites in stray dogs with the collaboration of the Kuala Lumpur City Council Pest Control Unit. Skin, organ, faecal and blood samples were analysed and results indicate that Babesia canis, Babesia gibsoni, Ehrlichia canis, Hepatozoon canis and microfilaria of Dirofilaria immittis are the common parasites species found in the blood and organ samples in 2014. The faecal floatation technique showed the presence ofhelminth ova such as Trichuris, Ancylostoma and Toxocara species. All skin samples were positive for Rhipicephalus sanguineus ticks. As strays are closely linked to human habitats such as market and housing areas, it is vital that stray population control is strategically implemented to safeguard these common zoonotic infections from spreading to humans.
显示更多 [+] 显示较少 [-]