The introduction of a highly virulent PRRSV strain in pig farms is associated with a change in the pattern of influenza A virus infection in nurseries

Table 1 Sneezing and cough indexes as recorded at 1, 3, 5, and 8 weeks of age

		Weeks of age (n° animals)	Sneezing	Cough	Deep cough
FARM 1		1 (n = 144)	0	0	0
		3 (n = 140)	0.079	0	0
	L1	5 (n = 262)	0.047	0.007	0
		8 (n = 202)	0.107	0.111	0.004
		1 (n = 222)	0	0	0
		3 (n = 210)	0.009	0.001	0
	L2	5 (n = 260)	0.003	0.005	0
		8 (n = 240)	0.050	0.001	0
FARM 2		1 (n = 460)	0	0	0
		3 (n = 460)	0.072	0	0
	L1	5 (n = 261)	0.085	0.001	0.002
		8 (n = 254)	0.070	0.080	0.001
		1 (n = 429)	0.115	0.32	0.004
		3 (n = 268)	0.080	0.016	0.007
	L2	5 (n = 253)	0.077	0.013	0.003
		8 (n = 190)	0.137	0.017	0.009

L1, longitudinal study 1; L2, longitudinal study 2.
Each index was calculated as the average count of sneezes or coughs recorded in 1 min divided by the number of pigs present.

ISSN: 1297-9716