Thyroxine dosage (total T4 or T4T)

Thyroxine (T4) is one of the main hormones secreted by the thyroid gland. Its measurement, particularly in total form (T4T), is a fundamental indicator of thyroid activity in animals. In animal health, this analysis makes it possible to identify hormonal imbalances linked to pathologies such as hypothyroidism or hyperthyroidism, but also to monitor the effects of enriched diets or functional food supplements.

T4 analysis is also used in animal nutrition studies, the development of new veterinary products or breeding programs.

Analytical methods: immunoassay or LC-MS/MS spectrometry

The dosage of total thyroxine is carried out according to two main approaches:

• LC-MS/MS (liquid chromatography coupled with tandem mass spectrometry): This method offers high sensitivity, increased specificity and allows precise quantification even at very low concentrations.
• Enzyme-linked immunosorbent assay (ELISA or similar): can be used for routine analyses on standard matrices, when sensitivity requirements are lower.

Analyzed matrices

The method applies to a wide variety of matrices from the veterinary and nutritional sectors, such as:

• Animal serums
• Plasmas or biological extracts
• Food supplements for animals
• Fortified foods

These matrices can concern various species (dogs, cats, cattle, horses, etc.) depending on the intended applications.

Industrial applications and challenges

Total thyroxine measurement is used in many contexts:

• Endocrine monitoring in pets
• Quality control of veterinary formulations
• Optimization of nutritional supplements enriched with iodine or thyroid-active extracts
• Assessment of biological response in veterinary clinical trials
• Monitoring side effects in drug treatments

Our analytical guarantees

At YesWeLab, we work with a network of expert and carefully selected partner laboratories, the majority of which are ISO 17025 certified and/or COFRAC accredited. We select the most suitable laboratory for each project based on:

• From the matrix to analyze
• Necessary analytical techniques
• Sensitivity or regulatory standards to be respected

Thanks to our digital platform, you can centralize, track and simplify your requests for thyroxine analyses and many other veterinary biomarkers.

Other useful additional analyses

For professionals in the veterinary sector, several additional analyses are often requested in parallel with the T4 dosage:

• Calprotectin dosage : for monitoring inflammatory conditions
• Lactate dehydrogenase (LDH) assay : to assess cellular integrity
• Transferrin loading capacity (TIBC) assay : an indicator of iron status
• Biomarker assay

You can also consult our complete catalog of animal health analyses to explore all our solutions.

Entrust your thyroid tests to YesWeLab

Since 2020, YesWeLab has been supporting manufacturers, distributors, veterinarians, and analysis laboratories in the outsourced management of their analytical needs. Our approach guarantees you:

• A single point of contact
• Rapid handling of your specific requests
• Reliable, traceable results that comply with current standards

Contact our scientific team now to obtain a personalized quote or discuss your technical specifications.