Feline Total Thyroxine (fT4)
Feline total T4 measurement is a primary screening aid for feline hyperthyroidism.
Fact Table
| Species | Feline |
|---|---|
| Biomarker | Total thyroxine (fT4) |
| Method | Fluorescence immunoassay (FICT) |
| Unit | nmol/L or µg/dL |
| Category | Endocrine |
Clinical Context
Feline total T4 measurement is a primary screening aid for feline hyperthyroidism.
Interpretation should always combine the quantitative result with the patient's signalment, history, clinical signs, and any other laboratory findings. A single value is rarely diagnostic on its own; serial measurements often provide more useful information.
Reference Range
Reference ranges vary by species, age and laboratory method — always interpret against the kit IFU and your in-house validation.
Related Test Kits
Related Articles
- Feline Hyperthyroidism: The T4 Test and Its Misses Hyperthyroidism is the most common endocrine disease of older cats, but early disease and concurrent illness can leave T4 normal. Here's the grey zone.
- Thyroid Testing in Dogs and Cats: T4 and TSH Explained A guide to thyroid testing in dogs and cats: total T4 and TSH ranges, hyperthyroidism in cats, hypothyroidism in dogs, and monitoring.
Manufacturer documentation + clinical literature cited in related articles
2026-09-12
MEDIUM — reference ranges are method-specific
FAQ
What does the Feline Total Thyroxine (fT4) test measure?
Migibio's Feline Total Thyroxine (fT4) test is a quantitative fluorescence immunoassay (FICT) run on the FIA680/FIA880 analyzer. It is intended as an aid in clinical assessment: Feline total T4 measurement is a primary screening aid for feline hyperthyroidism. The exact specimen, sample handling, and reporting units are specified in the kit IFU.
When is feline T4 testing most useful?
When clinical signs suggest a hormonal disorder, during breeding planning, or to monitor thyroid or adrenal function over time. Serial quantitative results are usually more informative than a single value. For cats, use the result with the clinical history, physical examination, and any other laboratory findings.
Why does this Data Hub not publish a universal reference range?
Reference ranges vary by species, age and laboratory method — always interpret against the kit IFU and your in-house validation.