Packaging and storage—
Preserve in tight containers, protected from light.
Labeling—
Label it to indicate that it is intended for oral veterinary use only.
Loss on drying 
731
—
Dry about 100 mg, accurately weighed, in a capillary-stoppered bottle in vacuum at a pressure not exceeding 5 mm of mercury at 60
for 3 hours: it loses not more than 2.0% of its weight.
Assay—
Assay preparation 1
(where it is labeled on a weight basis)—Dissolve about 3 g of Powder in an accurately measured volume of 0.01 N hydrochloric acid sufficient to obtain a solution containing not less than 1000 µg of chlortetracycline hydrochloride (C22H23ClN2O8·HCl) per mL.
Assay preparation 2
(where the label states the amount of chlortetracycline in the immediate container)—Transfer the contents of 1 container of Powder to an accurately measured volume of 0.01 N hydrochloric acid sufficient to obtain a solution containing not less than 1000 µg of chlortetracycline hydrochloride (C22H23ClN2O8·HCl) per mL.
Procedure—
Proceed with Powder as directed for chlortetracycline under
Antibiotics—Microbial Assays 81, using an accurately measured volume of
Assay preparation diluted quantitatively and stepwise with water to yield a
Test Dilution having a concentration assumed to be equal to the median dose level of the Standard.
