INTENDED USE

The Veterinary Thyroxine (T4) Test Kit is a fluorescence immunoassay intended for the quantitative determination of total thyroxine (T4) concentration in canine and feline serum or plasma. It is designed as a primary screening test for canine hypothyroidism and feline hyperthyroidism and to monitor response to thyroid hormone replacement or antithyroid therapy. Results should be interpreted with clinical signs and, where appropriate, TSH measurement. For veterinary use only.

PRINCIPLE

The test employs a competitive fluorescence immunoassay format appropriate for the small-molecule hormone thyroxine. Endogenous T4 in the specimen competes with a fluorescently labeled T4 analog for binding sites on anti-T4 antibodies, and the unbound fluorescent conjugate is captured at the test line (T line) immobilized with T4 antigen. Consequently, the T-line fluorescence intensity is inversely proportional to the T4 concentration in the sample. A control line (C line) verifies the procedure. The fluorescence analyzer reads the T-line/C-line signal ratio and reports a quantitative T4 value.

SPECIMEN

Serum or plasma (S/P). Fresh specimens are preferred; separate promptly, avoid hemolysis, and do not use serum separator tubes if specified by the platform.