484 Tapeworms of Chickens and Turkeys

J. L. GARDINER

AT LEAST ten different species of intestine immediately behind the giz- tapeworms may exist in chickens in zard) as the site of its activities. It is the United States. About a dozen one of the smallest species infesting species are found in turkeys and a half poultry and can be seen only by careful dozen, in ducks. Geese, guinea fowl, examination. Mature worms are about peafowl, and pigeons also harbor a one-sixth inch long and consist usually few species. of two to five segments, although there The total number of kinds of tape- may be as many as nine. worms infesting American poultry is Poultry kept in damp areas are most smaller than the figures might indi- likely to harbor the small chicken cate, however, because in most in- tapeworm, which is understandable stances a given species lives in more enough, as its intermediate hosts are than one kind of host. Tapeworms of several kinds of snails and slugs. poultry are less important than round- The small chicken tapeworm occa- worms or protozoans. Nevertheless, sionally occurs in turkeys, which also should any of them be present in play host to another species of the same sufficient numbers, particularly in genus, Davainea meleagridis. Neither has young birds, they will make their been reported as doing any harm to presence felt—to the detriment of both turkeys. the bird and its owner. The nodular tapeworm, Raillietina Tapeworms are parasites in the true echinobothrida, is one of the largest sense. Most of the creatures that we of poultry tapeworms. It may become call parasites are, strictly speaking, several inches long. It is distributed micropredators—they attack and eat widely through the country, Vjut it is their victim, just as a weasel attacks less common than somx other species. and eats its prey. The weasel, like most Ants arc its intermediate host. The so-called parasites, prefers to confine adult tapeworms infest chickens, tur- its feeding to certain favored portions keys, and occasionally pigeons, and of its kill. produce bumps, or nodules, in the Tapeworms, however, do not cat lower third of the small intestine their host. They live within it and wherever they attach themselves to the partake of its food, thus robbing it of intestinal w^all. The nodules are like nourishment. If many of them are the nodules caused l;y tuberculosis and present, they cause the host to lose may fool the poultry man into thinking weight and appetite and to become his flock has that disease. droopy and unthrifty. Intestinal Ants also are the intermediate hosts catarrh and diarrhea frequently are of the related Raillietina te tragona^ a linked with the presence of tapeworms. parasite of chickens, turkeys, guinea Young birds are affected more seri- fowl, and peafowl. ously by tapeworms than are older birds. The broad-headed tapeworm, Rail- The most serious tapeworm parasite lietina cesticillus, is common in chickens, of poultry throughout the United turkeys, and guinea fowl. Its name States probably is the small chicken describes it. It generally locates itself tapeworm, Davainea proglotiina. It in the front and middle parts of the occurs in the small intestine, and par- small intestine of its host. Tw^o dozen ticularly favors the duodenum (the or more species of beetles may be its horseshoe-shaped part of the small intermediate hosts. Among them are Tapeworms of Chickens and Turkeys 485

Roundvvorms in stomach; ta I )e worms in iiilestines

2 Chicken acquires Konndworm parasite by eating ejigs; in termed iale host tapeworm , I v,,^ segments ^^>i CJ33Q ^ with eggs passed in Larval ydrop})ings tapeworm (d eveloj) s Larval round- inside worm in cyst intermediate host)

apeworm egg

Roundworm egg

Eggs (enlarged) eaten by beetles, flies, slugs, earthworms, grasshoppers, etc. (intermediate hosts) The varions stages in an indirect life history of a tapeworm and a roundworm of poultry. the common meal-beetles that infest Choanotaenia infundibulum lives in both poultry feeds. chickens and turkeys. Domesticated fowls harbor a num- The pigeon tapeworm, Aporina dela- ber of other species of tapeworms, but fondi, which is confined to the pigeon none seems to be important. among domesticated fowl, has been re- Seven species of Hymenolepis occur in ported occasionally. ducks and geese. Two other species of No drug has yet been found that will that genus are parasites of chickens remove all tapeworms in poultry. For and turkeys. The hymenolepids have the species that do not fasten them- no common name, but you might call selves too deeply in the intestinal wall them the fragile tapeworms because of the host (such as the broad-headed of the way in which they break into tapeworm and Hymenolepis carioca)^ pieces when they are handled. butynorate, he:xachlorophene, and cer- Metroliasthes lucida^ a common tape- tain tin compounds have proved effec- worm of turkeys, also is found in tive. The catch to using these drugs is chickens and guinea fowl. Amoebo- that you have to be sure you are deal- taenia sphénoïdes is a species primarily ing with one of the tapeworms against parasitic in chickens. which they are of value. 486 Yearbook of Agriculture 1956 The best way to control tapeworms residual sprays. Malathion is a recom- is to attack them at their most vulner- mended fly poison for use in baits. able point—the developing stage in the Several substances, such as DDT, intermediate host. lindane, chlordane, and methoxy- If the droppings of the fowls are re- chlor, make good residual sprays. moved and attended to in such a way Keeping the poultry yards and that they are not usable as a breeding houses as free as possible of boards, place or shelter for beetles, ants, flies, boxes, and trash, which shelter the earthworms, slugs, or snails, the tape- potential intermediate hosts, is another worm eggs in the droppings cannot step in control. reach the intermediate host, which is Other helpful measures are the lim- necessary for their further develop- ing of damp places, especially near ment, and the tapeworms die. feed and water containers, and the The droppings may be treated with plowing up of poultry yards and seed- some substance, such as benzene hexa- ing them to low-growing vegetation. chloride dust, that kills the insects and other invertebrates that arc attracted JOHN L. GARDINER, a parasitologist in to them. the Agricultural Research Service, has The fly problem may be greatly re- worked in the field oj poultry parasites since duced by the use of poison baits and 1948,

Roundworms

J. U. GARDINER

MANY kinds of roundworms attack worked out for some kinds of round- poultry. Two or three of them occur worms, such as the gapeworm, cecal in all parts of the country and are worm, and large intestinal round- troublemakers everywhere. Several worm, but no drugs hav'C been found others occasionally cause severe losses. that will deal adequately with most of A roundworm that gets out of hand the roundworm parasites of poultry. has a great potential for harm. Prevention is better than cure. The digestive tract of the host is the Taking first things first: The location habitat favored by most poultry round- of the poultry runs should be chosen worms, but some roundworms attack with sanitation in mind. The ideal spot the eyes, air sacs, thoracic and abdomi- is a gently sloping piece of land with nal cavities, and the windpipe. Among sandy or gravelly soil and the best those that favor the digestive tract are possible drainage. specialists that prefer such an unlikely It is wise to rotate the runs. The organ as the gizzard for their base of four-yard system is perhaps the most operations, satisfactory. The ground assigned to Roundworms do damage in two one kind of fowl (chicken, turkey, or ways: By a direct attack on the tissues whatever it may be) is divided into of the host, which serve them as food, four equal lots by cross-fencing. The and by the elimination of toxic sub- poultryhouse is placed in the center, stances into the host's system. with a door opening into each lot. The Satisfactory treatments have been birds are rotated from one lot to an-