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

Table 11 The quantities of antimicrobial active ingredients used in nursery feed, water, and by injection as measured in weight-based and dose-based metrics (25 nursery 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	Avilamycin	Orthosomycin	1	1.2	0.4	7.2
	Chlortetracycline	Tetracyclines	18	204.3	19.7	377.9
	Lincomycin	Lincosamides	2	3.2	0.6	12.1
	Procaine penicillin G	Penicillins	8	28.9	2.2	42.1
	Sulfamethazine	Sulfonamides	6	26.0	5.9	113.5
	Tiamulin	Pleuromutilins	11	12.9	2.3	43.6
	Tylosin	Macrolides	1	20.9	6.7	129.8
	Tylvalosin	Macrolides	1	1.3	0.8	14.9
Injection	Benzathine penicillin G (with other antimicrobials)	Penicillins	2	0.01	0.007	0.14
	Enrofloxacin	Fluoroquinolones	2	0.02	0.002	0.04
	Lincomycin	Lincosamides	1	0.03	0.003	0.06
	Oxytetracycline	Tetracyclines	2	0.06	0.004	0.08
	Procaine penicillin G	Penicillins	11	1.13	0.084	1.61
	Procaine penicillin G LA	Penicillins	2	0.01	0.001	0.02
	Sulfadoxine (with trimethoprim)	Sulfonamides	2	0.43	0.018	0.34
	Trimethoprim (with sulfadoxine)	Dihydrofolate reductase inhibitors	2	0.09	0.018	0.34
	Tulathromycin	Macrolides	3	0.02	0.076	1.47
Water	Amoxicillin	Penicillins	5	32.2	2.01	38.7
	Apramycin	Aminoglycoside	2	6.9	0.69	13.3
	Penicillin G potassium	Penicillins	3	5.5	0.31	6.0
	Sulfamethazine	Sulfonamide	1	9.8	0.12	2.4
	Sulfathiazole	Sulfonamide	1	4.9	0.11	2.0
	Trimethoprim (with sulfadiazine)	Dihydrofolate reductase inhibitors	1	0.9	0.13	2.5
	Tylvalosin	Macrolides	1	1.1	0.23	4.4

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