Table 3.

Consumption of two main class C antibiotics, florfenicol and lincomycin, and two main class D antibiotics, amoxicillin and spectinomycin, in the pig production chain differentiated by the occurrence of porcine reproductive and respiratory syndrome (expressed as mg of active compound per total kg of meat produced).

Rearing phase:	Weaning		Fattening		SEM	Year				SEM	P -value
Productive chain1:	PRRS–	PRRS+	PRRS–	PRRS+		2017	2018	2019	2020		Chain	Phase	C × P	Year
Florfenicol	2.2A	32.8B	1.0A	4.1A	4.7	17.1	13.1	4.81	5.1	4.7	0.006	0.01	0.02	0.25
Lincomycin	7.4	30.5	5.8	24.8	10.9	11.1	11.8	10.6	35	10.9	0.10	0.75	0.86	0.33
Amoxicillin	8.0	32.9	0.7	1.7	10.9	15.6	13.3	8.01	6.4	10.9	0.24	0.08	0.28	0.93
Spectinomycin	16.5	19.7	0.4	1.9	2.1	11.5	12.1	6.0	8.9	2.1	0.31	<0.0001	0.71	0.22

¹PRRS–, the production chain originated from sows seronegative for porcine reproductive and respiratory syndrome; PRRS+, the production chain originated from sows seropositive for porcine reproductive and respiratory syndrome.

¹Means with differently labeled letters are significantly different at p < 0.01.