402
Important Helminth Parasites of Poultry
fasting. Though nicotine sulphate in doses of 2.5 minims to 0.3 c. c. is effec-
tive and reasonably safe, its two serious demerits are: its depressing action
on laying birds and the toxic symptoms which follow its use in birds in poor
condition.
The use of ' Iodine Vermicide' has already been indicated in the treat-
ment of taeniasis in poultry. It is highly effective both against tapeworms and
the intestinal round-worms and is also lethal to their eggs. It has been found
to possess a hundred per cent efficiency against ascaridia. The drug is not
only harmless but is definitely beneficial and safe for birds in poor condition.
Repeated treatments with this drug result in improvement in health and rate
of production. The drug is introduced directly into the gizzard. Another
organic compound of iodine, the glycerine-ester of 9-10 di-iodo-12 oxy.-octade-
cylic acid has also been found to be safe and 100 per cent effective against
these parasites.
Carbon tetrachloride is also very effective against ascaridiasis in poultry.
It is given at the rate of 0.75 c. c. per pound body-weight with a maximum
dose of 2 c. c. by means of a syringe and rubber tubing or preferably in capsules.
Starvation overnight is necessary. Following the administration of carbon
tetrachloride, the birds may suffer from diarrhœa and incoordination of
movement and activity, but these symptoms do not persist for long. Tetra-
chlorethylene, though quite effective, is more toxic to birds than is carbon
tetrachloride. Oil of chenopodium is also used in ascaridiasis. After fasting
the birds overnight, it is given at the rate of four drops per kilo-live-weight
in 3 to 4 c. c. of olive or raw linseed oil.
Flock treatment consists in feeding over a period of seven to eight days
of a mash containing 0.5 c. c. of nicotine sulphate (40 per cent nicotine) in
150 c. c. of water per lb. weight of dry mash. It has been found to be
harmless to birds and 82.5 per cent effective against the large intestinal
round-worm and 54.5 per cent against the caecum worm. Some people mix
into the mash two per cent by weight of tobacco dust and feed this daily for
a month to the infested birds. This is, however, much less effective than the
previous treatment. Both the individual and flock treatments are more
effective in the case of old birds than the young ones; and the surviving
worms are usually the immature forms of the parasite.
As the eggs develop to the infective stage in a minimum period of eight
days, it is essential for the control of ascaridiasis to remove droppings regular-
ly at intervals of at least five or six days. Occasionally lime dressing may be
applied and the soil dug over. Special attention should be paid to keep the
birds free from infection till they are three or four months old. Feed and
water should be free from contamination with the eggs of the parasite. Above
all, utmost care should be taken to provide a well-balanced feed, with adequate
quantities of vitamins-A and-B and of animal protein.
The commonest round-worms found in poultry are those occurring in
the caeca of birds. These belong to the genus Heterakis and inhabit the caeca
of the fowl, guinea-fowl, peafowl, turkey, duck, goose and a number of other