Assessment of vaccination of pigeons against paramyxovirus type 1 infection with inactivated aqueous‐suspension or oil‐emulsion vaccines

Abstract

SUMMARYThe immune response and resistance to PMV1 challenge of pigeons vaccinated with inactivated oil-emulsion (OE) or aqueous-suspension (AS) vaccines were compared. ASa was based on NDV LaSota strain, ASb on NDV Terumo strain, OEa on NDV Poletti strain and OEb on NDV Ulster 2C strain. Groups were each vaccinated subcutaneously with one of ASa (0.2ml), ASb (0.2ml), OEa (0.5ml), OEa (0.2ml) and OEb (0.5ml). An unvaccinated group was kept as control. The immune response measured by HI tests was the highest with the single 0.2ml dose of ASa vaccine. The single 0.2ml dose of OEa vaccine produced a poor HI response. Challenge with 'pigeon' PMV1 (intramuscular + intranasal/ocular) one month after vaccination resulted in the vast majority of unvaccinated pigeons excreting virus in the laryngeal secretions and the faeces and all . birds died. In comparison, virus shedding and morbidity-mortality were significantly reduced in the five challenged vaccinated groups. However, morbidity-mortality was higher in the OE groups than in the AS groups. No ASa vaccinated pigeon developed clinical signs and only one ASb vaccinated pigeon presented nervous signs. In contrast, morbidity-mortality reached 30 and 35% in the OE vaccinated groups.Only the inactivated aqueous-suspension vaccines, especially that prepared from NDV LaSota strain, gave, after one dose injection (0.2ml), high resistance to a severe challenge with 'pigeon' PMV1.

Efficacy of an inactivated aqueous‐suspension Newcastle disease virus vaccine against paramyxovirus type 1 infection in young pigeons with varying amounts of maternal antibody

“…The inactivated aqueous-suspension vaccine is based on the purified NDV-La Sota strain (10 9 EID 50 before inactivation, 0.2 ml dose) (Colombovac® PMV, Duphar AHD of Solvay) (Vindevogel et al, 1984;Duchatel et al, 1985;Duchatel & Vindevogel, 1986a).…”

“…Pigeons were kept under blind regular surveillance for 28 days, and virus isolation was attempted from the birds from laryngeal and cloacal swabs 3, 7 and 10 days after inoculation, as previously described (Duchatel & Vindevogel, 1986a). Percentages of pigeons shedding virus and cumulative percentages of nervous signs/mortality were compared by the Fisher test (Fisher, 1973).…”

“…Blood samples were taken from the mother pigeons before mating, and from squabs before and after vaccination at regular intervals as well as from the control pigeons. The antibody titrations were assessed by HI tests using the PMV-1 'pigeon' strain 135/81 as antigen (Vindevogel et al } 1982) as previously described (Duchatel & Vindevogel, 1986a).…”

“…This vaccine has been shown to induce a 1-year immunity in pigeons, when administered to PMV-1 seronegative pigeons (Duchatel et al, 1986;Duchatel & Vindevogel, 1986b. As the maternally-derived antibodies may interfere with induction of immunity, the aim of this study was to test the efficacy of the IASLV in young pigeons with and without maternally-derived antibodies born from vaccinated mothers.…”

“…An inactivated aqueous-suspension LaSota vaccine (IASLV) has been developed for the prevention of paramyxovirus infection in pigeons (Vindevogel et al, 1984;Duchatel et al, 1985;Duchatel & Vindevogel, 1986a) and is now licensed for use in the Netherlands, Belgium, Germany and England. This vaccine has been shown to induce a 1-year immunity in pigeons, when administered to PMV-1 seronegative pigeons (Duchatel et al, 1986;Duchatel & Vindevogel, 1986b.…”