Send to

Choose Destination
J Small Anim Pract. 2014 Mar;55(3):153-9. doi: 10.1111/jsap.12181. Epub 2014 Jan 20.

Measurement of thyroxine and cortisol in canine and feline blood samples using two immunoassay analysers.

Author information

Small Animal Hospital, School of Veterinary Sciences, University of Bristol, Langford, Bristol, BS40 5DU.



The AIA-360 (Tosoh Corporation) is an automated immunoassay analyser. The aims of this study were to estimate the precision of thyroxine and cortisol AIA-360 immunoassays in canine and feline samples and to compare the results produced with those obtained by a chemiluminescence analyser (Immulite® 1000, Siemens).


Blood samples from 240 clinical cases (60 dogs and 60 cats for both thyroxine and cortisol) were analysed using both instruments.


Deming regression calculations showed excellent correlation (thyroxine, canine rs  = 0 · 94, feline rs  = 0 · 97; cortisol, canine rs  = 0 · 97, feline rs  = 0 · 97). Agreement between the two instruments was examined by Bland-Altman difference plots, which identified wide confidence intervals and outliers for thyroxine (canine n = 6, feline n = 4) and cortisol (canine n = 3, feline n = 4) results. Inter/intra-run precision of the AIA-360 was excellent for both cortisol and thyroxine (coefficients of variation <7%).


The instrument showed excellent correlation for cortisol and thyroxine in canine and feline samples demonstrating that the AIA-360 can be used in clinical practice. The agreement studies suggest that the results from the AIA-360 cannot be used interchangeably with those generated by the Immulite 1000 and should be interpreted using reference intervals that have been established specific to the AIA-360.

Comment in

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center