tetano
Editor, Senior Moderator
Avian Dis. 2016 May;60(1 Suppl):226-31. doi: 10.1637/11145-050815-Reg.
[h=1]Comparative Effectiveness of Two Oil Adjuvant-Inactivated Avian Influenza H9N2 Vaccines.[/h] Kilany WH[SUP]1[/SUP], Bazid AH[SUP]2[/SUP], Ali A[SUP]3[/SUP], El-Deeb AH[SUP]4[/SUP], El-Abideen MA[SUP]1,[/SUP][SUP]5[/SUP], Sayed ME[SUP]5[/SUP], El-Kady MF[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Low pathogenic avian influenza H9N2 virus infection has been an important risk to the Egyptian poultry industry since 2011. Economic losses have occurred from early infection and co-infection with other pathogens. Therefore, H9N2 vaccination of broiler chicks as young as 7 days old was recommended. The current inactivated H9N2 vaccines (0.5 ml/bird) administered at a reduced dose (0.25 ml/bird) do not guarantee the delivery of an effective dose for broilers. In this study, the efficacy of the reduced-dose volume (0.3 ml/bird), compared with the regular vaccine dose (0.5 ml/bird) of inactivated H9N2 vaccines using two different commercially available adjuvants, was investigated. The vaccines were prepared from the local H9N2 virus (Ck/EG/114940v/NLQP/11) using the same antigen content: 300 hemagglutinating units. Postvaccination (PV) immune response was monitored using the hemagglutination inhibition test. At 4 wk PV, both vaccinated groups were challenged using the homologous H9N2 strain at a 50% egg infective dose (EID50) of 10(6) EID50/bird via the intranasal route. Clinical signs, mortality, and virus shedding in oropharyngeal swabs were monitored at 2, 4, 6, and 10 days postchallenge (DPC). The reduced-dose volume of vaccine induced a significantly faster and higher immune response than the regular volume of vaccine at 2 and 3 wk PV. No significant difference in virus shedding between the two vaccine formulas was found (P ≥ 0.05), and both vaccines were able to stop virus shedding by 6 DPC. The reduced-dose volume of vaccine using a suitable oil adjuvant and proper antigen content can be used effectively for early immunization of broiler chicks.
[h=4]KEYWORDS:[/h] AIV; LPAI H9N2; SPF chickens; inactivated vaccine
PMID: 27309059 [PubMed - in process]
[h=1]Comparative Effectiveness of Two Oil Adjuvant-Inactivated Avian Influenza H9N2 Vaccines.[/h] Kilany WH[SUP]1[/SUP], Bazid AH[SUP]2[/SUP], Ali A[SUP]3[/SUP], El-Deeb AH[SUP]4[/SUP], El-Abideen MA[SUP]1,[/SUP][SUP]5[/SUP], Sayed ME[SUP]5[/SUP], El-Kady MF[SUP]3[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] Low pathogenic avian influenza H9N2 virus infection has been an important risk to the Egyptian poultry industry since 2011. Economic losses have occurred from early infection and co-infection with other pathogens. Therefore, H9N2 vaccination of broiler chicks as young as 7 days old was recommended. The current inactivated H9N2 vaccines (0.5 ml/bird) administered at a reduced dose (0.25 ml/bird) do not guarantee the delivery of an effective dose for broilers. In this study, the efficacy of the reduced-dose volume (0.3 ml/bird), compared with the regular vaccine dose (0.5 ml/bird) of inactivated H9N2 vaccines using two different commercially available adjuvants, was investigated. The vaccines were prepared from the local H9N2 virus (Ck/EG/114940v/NLQP/11) using the same antigen content: 300 hemagglutinating units. Postvaccination (PV) immune response was monitored using the hemagglutination inhibition test. At 4 wk PV, both vaccinated groups were challenged using the homologous H9N2 strain at a 50% egg infective dose (EID50) of 10(6) EID50/bird via the intranasal route. Clinical signs, mortality, and virus shedding in oropharyngeal swabs were monitored at 2, 4, 6, and 10 days postchallenge (DPC). The reduced-dose volume of vaccine induced a significantly faster and higher immune response than the regular volume of vaccine at 2 and 3 wk PV. No significant difference in virus shedding between the two vaccine formulas was found (P ≥ 0.05), and both vaccines were able to stop virus shedding by 6 DPC. The reduced-dose volume of vaccine using a suitable oil adjuvant and proper antigen content can be used effectively for early immunization of broiler chicks.
[h=4]KEYWORDS:[/h] AIV; LPAI H9N2; SPF chickens; inactivated vaccine
PMID: 27309059 [PubMed - in process]