Antimicrobial use in lactating sows, piglets, nursery, and grower-finisher pigs on swine farms in Ontario, Canada during 2017 and 2018

Table 9 The quantities of antimicrobial active ingredients used in lactating sow feed as measured in weight-based and dose-based metrics (25 sow herds in the province of Ontario, Canada, May 2017–April 2018)

ROA	Antimicrobial active ingredients	Class	Number of herds	Mg/kg biomass	Doses_CA/pig^a	Dose_CA rate^a
Feed	Bacitracin	Bacitracins	1	12.25	2.72	118.4
	Chlortetracycline	Tetracyclines	3	19.73	1.90	82.5
	Oxytetracycline	Tetracyclines	2	15.13	1.99	86.6
	Procaine penicillin G	Penicillins	2	3.17	0.24	10.4
	Sulfamethazine	Sulfonamides	1	0.69	0.16	6.8
	Tilmicosin	Macrolides	1	0.31	0.31	13.6
Injection	Benzathine penicillin G (with other antimicrobials)	Penicillins	2	0.36	0.30	12.89
	Ceftiofur	Cephalosporins	1	0.02	0.01	0.31
	Oxytetracycline	Tetracyclines	7	1.50	0.25	11.07
	Procaine penicillin G	Penicillins	10	4.34	0.32	13.97
	Procaine penicillin G LA	Penicillins	3	0.58	0.09	3.76
	Sulfadoxine (with trimethoprim)	Sulfonamides	9	2.76	0.21	9.03
	Trimethoprim (with sulfadoxine)	Dihydrofolate reductase inhibitors	9	0.55	0.23	10.01

ROA route of administration
^aDoses_CA per pig = number of Canadian defined daily doses per pig; Dose_CA rate = number of Canadian defined daily doses per 1000 pig-days

ISSN: 2055-5660