Interaction between live avian pneumovirus and Newcastle disease virus vaccines in specific pathogen free chickens

Figures & data

Table 1.  Experimental design to study the effects of vaccination with APV or NDV alone or together

Vaccine	Inoculum	Number of chicks	Group designation	Dose
Unvaccinated	SW	12	C	–
Nemovac^®	APV	16	A	2.4 log10 CCID50 ^a
Avinew^®	NDV	16	N	5.6 log10 EID50 ^b
Nemovac^®+Avinew^®	APV + NDV	16	AN	Both N and A mixed together
All vaccines given via the oculo-oral route at 1 day old.
^aCCID50, median cell culture infective dose.
^bEID50, median egg infective dose.

Table 2.  Detection of APV in swabs and tissues by RT-PCR and passage in tracheal organ cultures

Sample	Group		Days post-vaccination
OP swabs				10 days		16 days		24 days
IOS swabs and tissues			7 days		14 days		21 days		28 days
OP swab	Nemovac^® (N)	RT-PCR^a		+b		–		–
		VI^c		3d		0		0
	Nemovac^®+Avinew^® (AN)	RT-PCR		–		+		+
		VI		0		1		0
IOS swab	Nemovac^® (N)	RT-PCR	+		+		–		–
		VI	1		0		0		0
	Nemovac^®+Avinew^® (AN)	RT-PCR	–		+		–		–
		VI	0		1		0		0
Turbinate	Nemovac^® (N)	RT-PCR	+		+		–		–
		VI	0		0		0		0
	Nemovac^®+Avinew^® (AN)	RT-PCR	+		+		–		–
		VI	0		1		0		0
Trachea	Nemovac^® (N)	RT-PCR	–		–		–		–
		VI	0		0		0		0
	Nemovac^®+Avinew^® (AN)	RT-PCR	–		–		+		–
		VI	0		1		1		0
^aVirus detection by RT-PCR.
^bPositive or negative from pooled OP swabs or tissues.
^cAttempted virus isolation.
^dNumber positive of four pools of OP or tissues examined.

Table 3.  Attempted isolation of NDV from swabs and tissues by passage in embryonated chicken eggs

Sample	Group	Days post vaccination
OP swabs		2 days	5 days
IOS^b swabs and tissues				7 days	14 days
OP swab	Avinew^® ^(A)	2^a	4
	Nemovac^®+Avinew^® (AN)	4	3
IOS swab	Avinew^® (A)			2^b	0
	Nemovac^®+Avinew^® (AN)			3	0
Trachea	Avinew^® (A)			1	0
	Nemovac^®+Avinew^® (AN)			4	0
Lungs	Avinew^® (A)			2	0
	Nemovac^®+Avinew^® (AN)			4	0
Proventriculus	Avinew^® (A)			1	1
	Nemovac^®+Avinew^® (AN)			2	0
Caecal tonsil	Avinew^® (A)			2	2
	Nemovac^®+Avinew^® (AN)			3	1
Liver	Avinew^® (A)			2	2
	Nemovac^®+Avinew^® (AN)			4	0
^aNumber positive of four pools examined.
^bNumber positive of four tissues examined.

Figure 1. NDV haemagglutination inhibition antibodies in the unvaccinated (C), APV (N), NDV (A) or dual-vaccinated (AN) groups. Different superscripts at similar sampling times indicate that titres differ significantly (P<0.05).

Figure 2. APV ELISA antibodies in the unvaccinated (C), APV (N), NDV (A) or dual-vaccinated (AN) groups measured using APV type B-coated ELISA plates. The birds were vaccinated with same strain as the ELISA antigen. Different superscripts between groups indicate that the values differ significantly (P<0.05).

Figure 3. 3a: NDV-specific IgA in lachrymal fluid of unvaccinated (C), APV (N), NDV (A) or dual-vaccinated (AN) chickens. 3b: NDV-specific IgG in lachrymal fluid of unvaccinated (C), APV (N), NDV (A) or dual-vaccinated (AN) chickens.

Figure 4. NDV-specific IgG in tracheal washes of unvaccinated (C), APV (N), NDV (A) or dual-vaccinated (AN) chickens.

Figure 5. 5a: APV-specific IgA in lachrymal fluid of unvaccinated (C), APV (N), NDV (A) or dual-vaccinated (AN) chickens. 5b: APV-specific IgG in lachrymal fluid of unvaccinated (C), APV (N), NDV (A) or dual-vaccinated (AN) chickens.