Table 3.

Drug use before the time of second sampling, by class

Drug Class	Total ADD's Analyzeda	% of ADD's	No. of Cattle Exposed	% of Cattle Exposed
Parenteral Betalactam	211	0.4	73	1.5
Parenteral Quinolone	57	0.1	19	0.4
Parenteral Phenicol	81	0.2	27	0.5
Parenteral Macrolide	3,166	5.7	1,158	23.3
Parenteral Sulfonamide	51	0.1	17	0.3
Parenteral Tetracycline	4,540	8.2	1,563	31.4
In‐feed Tetracycline	47,178	85.2	4,979	100.0
In‐feed Macrolide	63	0.1	477	9.6
Total	55,346

^aADD = animal daily dose, defined as the number of days that a single treatment remains in the target tissue(s) at therapeutic concentrations.