Isolation and identification of the Newcastle disease virus from field outbreaks in broiler and layer flocks in Iraq

Abstract

<jats:p> Newcastle disease is one of serious pathological problems and causes of vast economic losses during 2011-2016 in Iraq. The disease caused high mortalities in all types of poultry nevertheless of vaccination. In this study all samples were collected from infected flocks with clinical signs of the disease. Inoculation of chicken embryonated eggs was carried out for virus isolation, identification, Haemagglutination and Haemagglutination Inhibition assay. Using Reverse Transcriptase-Polymerase Chain Reaction to confirm the presence of the virus, Intra Cerebral Pathogenicity Index and Mean Death Time were used to confirm all the isolates that were velogenic. The important determinant of Newcastle disease virus pathogenicity is fusion protein that has been used for phylogenetic analysis. sequencing and compared genetically of Newcastle disease virus Iraqi isolate to publish sequences acquired from GenBank showed 99% sequence similarity to the Iran isolate IRI 1392k (KJ176996.1). It can concluded from these data that introduction new virus was occurred in Iraq.</jats:p>

Using T cell lymphokines to enhance the immune response against Newcastle disease in vaccinated broiler chickens fed naturally contaminated diet with different mycotoxins

“…Group 5 which showed opposite results because birds were not vaccinated and not protected against NDV and these results went with (16). Also Group 4 shows opposite results Due to the mycotoxins toxic effects, which is in agreement with (10).…”

“…Immune response in G1 was better than G2 the results were consistent with (10), who demonstrated that the immunogenicity of the live vaccine was a cellular immunity primarily dependent on Cytokines and its role in stimulating many defense cells against infectious antigens, While the vaccination with killed vaccines stimulating Humoral immunity, which relies on the stimulation of B cells that produce Ab according to amount of Ag in the killed vaccine without reliance on other defense cells, which explains the slow immunity available from the killed vaccines. The reason of increase in immune response in G5 after challenge virulent local isolate of ND, return to not vaccinated against ND to protect the chicks from infection, These results agreed with (16), who proved that the chicks were exposed to NDV infection in the third week after decline the maternal immunity and highly increase of Abs with high mortality in chicks due to acute infection. But the low Ab titre in G4 return to toxic effect of mycotoxin these results agree with (4) show that mycotoxins damage the proteins found in cell junctions and thus reduce the transmission of electrical impulses, that transfer of cytokines between immune cells.…”

“…Also agree with results of (18), whom proved decrease in oxidative status and increase in antioxidant defense in bird vaccinated with live vaccines of ND and challenge with virulent local isolate of ND. While G5 which showed opposite results because birds were not vaccinated and not protected against NDV these results go in the line with (16). A Group 4 shows opposite results because of the toxic mycotoxins effects which have been closely associated with ROS generation mainly include hydroxyl (OH-), O2 and hydrogen peroxide (19).…”

Evalution of the Best Vaccinal Routes Against Newcastle in the Production Stage of Laying Hens

“…The respiratory and digestive tracts of birds are part of their mucosal immune system. While parenterally delivered vaccinations mainly trigger systemic reactions, mucosal immunization promotes mucosal immune responses with S-IgA antibody as well as systemic humoral and cellular immunological responses (17,29). When compared to other vaccination methods, mucosal delivery offers a number of benefits, including a wide epithelial surface with a lot of microvilli, a porous endothelium membrane, a highly vascularized mucosa that facilitates absorption, and ready accessibility (28).…”