FEATURE


Undigested seed in droppings, indicative of digestive dysfunction - most commonly PDD.


Stained histological slide of tissue (pink) showing infiltration of inflammatory cells (blue) around a nerve


clinical signs may be seen if foreign bodies, intestinal parasites, or yeast infections are involved, but at PME the stomach wall in these examples is usually thickened. Heavy metal poisoning (zinc and lead) can also result in vomiting and weight loss, but usually with blood in the droppings. However, the intensity of clinical signs is


Radiograph showing distended proventriculus (arrowed) so thin-walled that seed material can be seen within. Barium has been given as a contrast medium, as shows as white in the crop (left) and the intestine (right)


Typical signs in clinically affected birds


are weight loss, the passing of undigested seeds in the droppings, and vomiting. Radiography (X-ray examination) in these cases will show an enlarged proventriculus, and post-mortem examination (PME) confirms the enlargement, with extreme thinning of the stomach wall. Similar


very variable, and can be very gradual in onset. Many birds will also show neurological signs, including balance issues and blindness. Julia showed a video of a cockatoo having difficulty in holding on to its perch, and picking up food items awkwardly. Feather plucking can also be a side effect in infected parrots. The virus produces these variable signs by invading nerve bundles and ganglia, and depending on which nerves are inflamed, so the clinical signs will vary. Definitive diagnosis rests on identifying this ganglioneuritis histologically, with masses of inflammatory


BIRD SCENE 19


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50