TABLE 4.

Detection of virus in nasal swabs, tonsil scrapings, and blood samples obtained after challenge of N1v-vaccinated animals with virulent BICv

Group	Sample	No. of animals positive for virus isolation/ total no. of challenged animals at daya:
		C	4	6	8	12	14	21
Group challenged	Nasal	0/4	0/4	0/4	0/4	0/4	0/4	0/4
3 dpi	Tonsil	0/4	0/4	0/4	0/4	0/4	0/4	0/4
	Blood	0/4	4/4 (3.96)	0/4	0/4	0/4	0/4	0/4
Group challenged	Nasal	0/4	0/4	0/4	0/4	0/4	0/4	0/4
28 dpi	Tonsil	0/4	0/4	0/4	0/4	0/4	0/4	0/4
	Blood	0/4	0/4	0/4	0/4	0/4	0/4	0/4
Control group	Nasal	0/3	0/3	1/1 (6.63)	1/1 (4.3)
	Tonsil	0/3	1/3 (1.97)	1/1 (4.8)	1/1 (1.97)
	Blood	0/3	1/3 (2.47)	1/1 (7.8)	1/1 (7.8)

^aDay C, day of challenge. Other days are days postchallenge. Numbers in parentheses indicate average virus titers expressed as log₁₀ TCID₅₀/ml.