A. E. Hamerton—Diseases of Aviary Birds



75



inflammation and gangrene of this part of the bowel. It is a most

destructive disease amongst gallinaceous birds and pigeons.


Spiroptera, or hair worms, infest the gizzard and proventiculous of

Waterfowl and gallinaceous birds, and cause death by burrowing under

the mucosa and setting up severe inflammation.


A Filaria- like worm ( Diplotrixna tricuspis) is sometimes found in

the body cavity of Jays that have died of pneumonic consolidation

of the lungs. This worm causes fatal avian pneumonia by laying its

eggs in vast numbers in the tissues of the lung, in which they can be

readily detected on microscopical examination of the affected organ.


Tapeworms (Cestodes ) are common intestinal parasites of aviary

birds. They do not usually cause disease, except when found in very

large numbers, they may then cause death by intestinal obstruction

or inflammation.


Flukes or flatworms (Trematodes) are sometimes found infesting the

kidneys of Egrets, and possibly other water birds. If in large numbers

they may set up a verminous nephritis, resulting in death from dis¬

organization of the kidneys. The eggs of the parasite are readily found

on microscopical examination of the contents of ureters or cloaca.


Microfilaria. —The larval forms of filaria worms are sometimes found

concentrated in great numbers in the capillaries and alveoli of the lungs

of birds that have died from pulmonary congestion and oedema, and

they can hardly be acquitted of being concerned in causing the fatal

lesion.


The air-sac mite (Cytolechus nuedus ) infests the air sacs, and may

cause purulent inflammation therein.


Coccidia are protozoal parasites infesting the intestinal epithelium

of birds. They set up intractible diarrhoea that is most destructive

to young birds. Coccidiosis can be diagnosed only by microscopical

examination of the excreta, in which the characteristic oocyst can easily

be recognized. When the parasites infest the caecal epithelium the lesions

produced may closely resemble those caused by heterakis worms ;

minute inspection with the naked eye or hand lens will exclude the

worm infection.


Other protozoal parasites of birds, viz. those of bird malaria

{Plasmodium) , are of special interest, in that they were studied by Ronald



