212 DISEASE IN WILD MAMMALS AND BIRDS 
mens had not been put upon the correct flooring or 
caging. Unbroken seeds may obstruct the lumen. 
Mechanical Obstruction. 
Although the following is not constipation it is well to 
cite at this place an experience which amounted to 
mechanical intestinal obstruction. A number of finches 
were subjected to postmortem and found to have whole 
white millet seeds in their intestines, tliis being the only 
discoverable cause of death. Investigation revealed that 
during the night mice ate the canary seed in the pans, 
lea^dng only the millet, which the hungry birds consumed 
whole. Small birds can take a few millet and crack them 
when eating leisurely, but apparently not when hungry. 
When the food was removed at night the trouble ceased. 
Obstruction by sand is well illustrated by a peculiar 
form of pica, in a goose, which is w^orth citing, and calls to 
mind the sand disease of horses : 
Canada Goose 6 {Branta canadensis canadensis). 
Diagnosis. — Masses of sand in entire intestinal tract. The general 
condition externally and internally is good. The crop is distended like 
a sausage, quite firm and the overfilling is obviously due to sand in 
which veiy few stones, which could be called pebbles, are found. This 
mass continues into the esophagus making the whole tract impassable 
for food. The mucosa is a little pink and dirt-stained in places but is 
not visibly inflamed. The gizzard is contracted over a mass of sand 
but no food. Sand in more or less definitely packed condition is found 
all along the gut tract, in one place in the small coil it being quite as 
tight as in the crop and no lumen remaining. Sand and bits of shale 
are found in ceea. The organs are apparently healthy, slightly pale 
perhaps, but certainly not distinctly anemic. No infection exists. The 
aorta, just above renals, has a 15 mm. x 2 mm. pale opacity of same 
consistency as the rest of the vessel, just perceptibly higher than sur- 
rounding surface. 
"Sand disease" has occurred in a Persian Wild Ass 
(Equus onager) causing in this case ulceration, perfora- 
tion and peritonitis, a Common deer {Mazama virginiana) 
and a Chapman's zebra {Equus hurcheUi cJiapmani). 
The collection of sand is always greatest in the caput coli, 
but may coat the large bowel to the anus. 
