Abstract
Proventricular dilatation disease (PDD) is characterised by weight loss, physical weakness,
regurgitation and/or neurological signs. PDD is a serious problem for the population of Spix’s
macaws (Cyanopsitta spixii) at Al Wabra Wildlife Preservation (AWWP), Doha, Qatar. During their
annual health checks, radiographs are taken in accordance with the official health programme
guidelines for the species. Radiograph image measurements of proventriculus diameter,
hourglass waist, liver width and keel height enable calculation of the proventriculus diameter-tokeel
height ratio which might be a useful indicator of a birds PDD status. In addition, the change
in these values from 2004 to 2007 was evaluated. From the measurements of proventriculus
width, we did observe a trend of increased large proventricular diameters in positive birds, lower
in birds suspicious for PDD and lowest in birds with no obvious PDD lesions, as diagnosed by
crop biopsy. Proventriculus diameter-to-keel height ratio did not differ significantly between
positive and non positive birds (classified by crop biopsy), but reflected a similar trend to
proventriculus width. Therefore, radiographic proventricular diameter measurements might be a
useful initial indicator for carrying out crop biopsies in birds to detect PDD. From January 2007 to
September 2007, there was a significant decrease of proventriculus diameter, hourglass waist
and liver width that was interpreted as an effect of significant dietary changes instigated in 2005
and further refined in 2007.