Abstracts | EQUINE
Evaluation of dynamic testing for pituitary pars intermedia
dysfunction diagnosis in donkeys
S. Mejia‐Pereira A. Perez‐Ecija B. R. Buchanan R. E. Toribio F. J. Mendoza
First published: 26 October 2018
Background
Endocrine disorders are common in donkeys. Pituitary
pars intermedia dysfunction (PPID) is thought to be a
frequent disturbance in donkeys due to their longevity.
However, information on PPID dynamic testing in
donkeys is lacking.
Objectives
The objective of this study was to evaluate the
previously described guidelines for PPID diagnosis in
horses in donkeys with suspicion of PPID.
Study design
Prospective experimental study.
Methods
Eighty
donkeys
were
evaluated
for
PPID
suspicion based on clinical signs and baseline
adrenocorticotropic hormone (ACTH) concentrations.
Six mix‐breed donkeys (one jack and five non‐pregnant
jennies) fulfilling inclusion criteria were subjected to
dexamethasone suppression test (DST), thyrotropin‐
releasing hormone stimulation test (TRH) and
combined DST–TRH challenge. Tests were interpreted
according to guidelines for PPID diagnosis in horses.
failed to detect those animals and showed conflicting
results. Similarly, cortisol basal concentrations were
not consistent with PPID suspicion.
Main limitations
Characterisation of seasonal and geographical location
effect on baseline ACTH concentrations and response
to TRH is compelling in this species. Further studies
with a larger number of donkeys are needed.
Conclusions
This is the first study in donkeys to evaluate common
dynamic tests used for PPID diagnosis in horses.
Preliminary results agree with the guidelines for PPID
diagnosis in horses and baseline ACTH measurement
followed by TRH challenge are recommended tests for
diagnosis of PPID in donkeys.
https://doi.org/10.1111/evj.13034
Results
Donkeys fulfilling inclusion criteria were diagnosed
with PPID by TRH stimulation test (six of six). Both
DST (three of six) and DST–TRH (4/6) challenges
• Volume 21 Issue 1 | March 2019 •
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