Abstracts | EQUINE
Evaluation of dynamic testing for pituitary pars
intermedia dysfunction diagnosis in donkeys
S. Meija-Pereira, A. Perez-Ecija, B. R. Buchanan, R. E. Toribio F. J. Mendo
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.
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://onlinelibrary.wiley.com/doi/pdf/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 failed to
detect those animals and showed conflicting results.
• Volume 21 Issue 1 | March 2019 •
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