H. D.
SRIVASTAVA
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mornings, the birds should not be let loose in the morning until the dragon-
flies are out of the weeds.
Another fluke, Lepoderma arcuatum, has also been reported from the
oviduct of the fowl in Russia, but nothing is definitely known about its patho-
genicity and life-history.
The intestine may harbour large numbers of worms of different species
of the families Echinostomidae, Strigeidae and Plagiorchiidae. Members of
the family Echinostomidae occur in the duodenum, small intestine, rectum
and rarely caeca of the fowl, duck and goose. The eggs are discharged in the
gut of the host and pass out with the droppings. Under favourable condi-
tions, the eggs hatch and the miracidia penetrate into a suitable molluscan
host and develop into cercariae. The latter come out and encyst either on
another snail, an amphibian or fish. The final host acquires infection by
ingesting the second intermediate host bearing encysted larvæ. In light
infestations, these parasites do not produce any marked symptoms, but when
present in large numbers they may be responsible for severe enteritis. The
birds show inappetence, diarrhœa and emaciation. Diagnosis is made by
finding eggs of the parasite in the droppings. The most successful method
of treatment is the administration of carbon tetrachloride, in doses of 1 to 2
c. c. with about 3 c. c. of liquid paraffin, by means of a syringe and 10 cm.
long narrow rubber tubing which is pushed into the oesophagus.
Representatives of the family Strigeidae occur usually in the intestine of
aquatic birds. Their life-cycle is similar to those of the Echinostomids ; the
second intermediate hosts being a fish, snail, leech, etc. These parasites
live firmly attached to the mucosa of the intestine and draw in a number of
villi into the anterior cup-shaped part of their body. The blood vessels in
the villi become hyperanaemic and burst and the parasite feeds on the tissue
and blood of the host. The degenerated villi are digested by the secretion of
the glands of the adhesive organ. By their peculiar mode of feeding the
worms, in heavy infestation, cause severe irritation and haemorrhagic enteritis,
resulting in anaemia, loss of condition and at times death. As the worms are
blood-suckers, carbon tetrachloride in doses of 1 to 2 c. c. is indicated, but it
would appear from the mode of feeding of these parasites that no drug will
be ingested from the lumen of the intestine and hence therapy via the blood
may be more successful. In the development of all flukes, snails serve as
intermediate hosts, hence their extermination should also be attempted.
Certain species of Plagiorchis are known to occur in the gut of ducks,
turkeys and wild birds and, when present in large number, they may be res-
ponsible for acute enteritis and frequent death. Recently, an outbreak of
parasitic necrosis in turkeys caused by P. laricola has been reported from
Ireland. Out of a flock of 23 birds all but one died. All the birds
showed similar symptoms, viz. droopiness and failure to put on weight, and
ultimately died. There was marked necrotic enteritis affecting the whole of
the small intestine and duodenum. Treatment with ten grains of Kamala per
bird was entirely unsuccessful. Carbon tetrachloride was not tried.
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