Ctahr.hawaii.edu

Livestock Management
April 2007
Parasites Important to Poultry in Hawai‘i
and Their Control
Hawai‘i is home both to a commercial poultry in­ Important parasites of poultry in Hawai‘i
dustry and to many small rural homesteads that The most common and economically important internal raise chickens for subsistence, hobby, show, or simply poultry parasites in Hawai‘i include the large roundworm for pleasure. The owners of many of these smaller farm (Ascarida galli), the gapeworm (Syngamus trachea), flocks have often adopted a free-range type of manage­ tapeworms (Davainea proglottina and Raillietina spp.) ment. The free-range management is certainly an ac­ and coccidiosis (Eimeria sp.) The common red mite, or ceptable type of husbandry practice, but there are some the roost mite (Dermanyssus gallinae), is an important special health considerations to keep in mind, especially external parasite that can cause great economic loss if in the area of parasite control. Free-ranging birds have an increased opportunity to encounter the infective eggs, The large roundworm (Ascarida galli) is about larvae, and intermediate hosts of parasites that can cause 11⁄2–3 inches long and lives in the intestines of the bird. Symptoms of infection with this parasite include poor Healthy birds are a prerequisite for success in raising flesh, unthriftiness, weakness, reduced egg production, poultry, regardless of the overall goals of the owner. weight loss, and pale head and legs. Parasite eggs are Unhealthy birds result in financial losses in terms of passed in the feces and develop to an infective stage in death and treatment costs. It is well documented that about 10–20 days. Parasite eggs are then ingested by diseases and parasites are the cause for millions of dollars another chicken, and the larval or baby worms hatch in of losses to poultry producers each year. Death losses the host’s intestine and grow to maturity in 6–8 weeks. are an obvious loss, but even greater economic losses The common earthworm can serve as a transport host. are associated with decreased growth, egg production, Good management and husbandry is important to control and feed efficiency among the living. Parasites are an this parasite. Young birds should be separated from older important cause of this hidden economic loss. Not all birds, yards and pens should be rotated and cleaned, and poultry losses can be prevented, but they can be reduced, deep-lit er pens must be kept dry. Droppings should and the more knowledgeable the producers, the more be removed frequently. Several wormers, including thiabendazole, fenbendazole, cambendazole, pyrantel, Prevention and control of parasites is one of the mebendazole, and levamisole, are effective in killing quickest, cheapest, and most dependable methods of increasing production, with no requirements for extra Originally published in 1995 as Hawaii Animal Health Series Fact birds or additional feed costs. Only a small increase in Sheet #95-1; reissued with minor revisions. Brad LeaMaster is a for­ mer veterinarian with the CTAHR Department of Animal Sciences. Published by the College of Tropical Agriculture and Human Resources (CTAHR) and issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in coopera­tion with the U.S. Department of Agriculture. Andrew G. Hashimoto, Director/Dean, Cooperative Extension Service/CTAHR, University of Hawai‘i at Mänoa, Honolulu, Hawai‘i 96822. An equal opportunity/affirmative action institution providing programs and services to the people of Hawai‘i without regard to race, sex, age, religion, color, national origin, ancestry, dis­ability, marital status, arrest and court record, sexual orientation, or status as a covered veteran. CTAHR publications can be found on the Web site Parasites Important to Poultry in Hawai‘i and Their Control Ascarida galli
Syngamus trachea
(Davainea proglottina) and the broad-headed tapeworm (Raillietina cesticellus). Both species of adult tapeworm live in the intestines of the birds. The segments of the minute tapeworm pass out in the feces, and eggs con­ The gapeworm (Syngamus trachea) lives in the tra­ tained in the segments hatch after being swallowed by chea, or windpipe of chickens. Adult worms are red and any of several species of slug, which serve as the inter­ range in length from 3 to 8 inches. Young birds are the mediate host. Within the slug, the tapeworm develops most seriously affected. Infected birds crouch, extend to an intermediate stage called a cysticercoid in about their necks, and gasp for breath because of mechani­ 3 weeks. When the slugs containing the tapeworm are cal obstruction of the trachea by adult worms. There is eaten by a chicken, the intermediate tapeworm stage usual y a mucus excretion and convulsive head shaking. is released and develops to an adult in about 2 weeks. Death may result from asphyxia or progressive emacia­ The intermediate hosts for the broad-headed tapeworm tion and weakness. Birds become infected directly by are many species of beetles or the housefly. The min­ ingestion of embryonated eggs or by the ingestion of ute tapeworm is considered to be highly pathogenic. earthworms containing free or encysted gapeworm lar­ Infected birds show marked weight loss, general debil­ vae. Gapeworm larvae may remain infective in the earth­ ity, unthriftiness, and stunted growth. Egg-laying may worm for over 4 years. Passage through earthworms is stop. Birds on range are more liable to become infected thought to render larvae more highly infective, enabling than those in pens and dry yards. Slug, fly, and beetle strains to transfer more readily from one bird species to control is necessary. Infected birds can be treated with another.After ingestion, the larvae travel via the blood to niclosamide (Yomesan® in the food) or mebendazole to the lungs and migrate via the air passages to the trachea. The prepatent period is 2–3 weeks and the adults live Coccidiosis disease of poultry is caused by a single- 4–8 months. Control of this parasite is by avoiding pens celled protozoan parasite (Eimeria sp.). Disease is most and yards with wet, organic soils with large numbers of frequently seen in young birds 4–6 weeks of age. De­ earthworms. Place birds on fresh ground; contact with pending on the size of the bird, the immune status and wild birds should be control ed. The drugs used to control the infective dose, signs of infection can range from no the large roundworm will also have efficacy against the apparent signs to death. It is frequently an acute disease with bloody droppings. Birds are ruffled, sleepy, and Several species of tapeworms infect chickens. The unthrifty. A severe anemia may occur because of blood two most common in Hawai‘i are the minute tapeworm loss. Droppings of infected birds transmit the disease. Parasites Important to Poultry in Hawai‘i and Their Control Eimeria species
Raillietina species
The coccidia eggs (or oocysts) can persist in the environ­ ment for a long time, especially in warm moist climates such as Hawai‘i . Good management, such as raising young birds apart from older birds, keeping litter dry, Dermanyssus gallinae
cleaning feeders and waterers weekly, and sanitation, is required to prevent and control this disease. Many anti-coccidias are effective in preventing infections but have little value in treatment. For treatment, the most commonly used drugs are the sulfonamides and amp­ rolium. These drugs can be given in the feed or water. Use of reventive measures, without complete reliance on drugs, is the most prudent program to follow. The common red mite or roost mite (Dermanyssus gallinae) is an important external parasite of chickens, wild birds, and occasionally man. The mite breeds in the bird’s environment and attacks its host at night. After a blood meal, the adult mite is red, about 1 mm long, and in large numbers they are sometimes described as “mov­ ing paprika.” The eggs of the mite are usually laid after a blood meal and are deposited in cracks and crevices in the walls of the poultry house or in the nest boxes. Eggs hatch in 2–3 days, and the life cycle may be completed in 7–9 days under optimal conditions. Adults may survive 4–5 months without feeding. Mites are spread by direct contact with infested birds or contaminated equipment during the day, cleaning of equipment, cages, and bird’s and poultry litter. Infested birds are frequently uneasy quarters is more important than treating individual and do not rest well at night. Birds in production may birds. Contact with wild birds such as sparrows should refuse to lay in infested nests. Decreased egg produc­ be prevented. Sevin® (carbaryl) controls this mite and tion, anemia, paleness, droopiness, and death are signs should be applied every 2–3 weeks. Dusts and sprays of of infection. Because this mite is generally off the host Parasites Important to Poultry in Hawai‘i and Their Control A program of health, disease prevention, and
parasite control
6. Use a veterinarian and a diagnostic laboratory. A Preventing disease is much more economical than treat­ veterinarian and a diagnostic laboratory can assist in ing a disease outbreak. Although the exact program will making the right treatment choices. thereby avoiding vary according to the specific conditions on each indi­ heavy losses if the wrong medication is given.
vidual farm, the basic principles are the same.
7. Dispose of carcasses properly. Sanitary disposal of 1. Get clean stock. Clean stock simplifies the problem dead birds is essential for the control of disease, flies, of disease control by reducing the number and severity of problems that are present when the flock is established. 8. Periodical y vacate and clean. All poultry buildings Purchase stock from breeders who participate in orga­ should periodically be vacated, thoroughly cleaned. and disinfected. This is an effective way to prevent the 2. Avoid bringing infection in. Quarantine newly acquired birds and watch for any signs of disease. Keep out unnecessary visitors and equipment.
References
3. Fol ow a vaccination program. Vaccination is cheap Calnek, B.W. 1991. Diseases of poultry. Iowa State Univ. insurance against losses from certain diseases.
4. Control internal and external parasites and reduce Foreyt, W.,J. 1990. Veterinary parasitology reference stresses. Feed is too costly to feed to parasites. Control­ manual. Washington State Univ., Pullman, Washing­ ling parasites helps maintain birds in good condition so 5. Recognize disease early. A good caretaker should Disclaimer. Trade names are included for the benefit of set aside a time each day for the purpose of observing the reader and do not imply endorsement by the Uni­ the flock. Note changes in birds’ actions, eating and drinking, and unusual sounds like sneezing or rattling. Good recordkeeping helps recognize the early stages of Drawings of life cycles reproduced with permission trouble by showing slumps in feed and water consump­ Parasites Important to Poultry in Hawai‘i and Their Control Table 1. Important parasites of poultry in Hawai‘i, the common symptoms of infection, and products for treatment.
Parasite
Symptoms
Treatment
Fenbendazole (Panacur®, Safe-Guard® 30 mg/lb/day, 3days) Mebendazole (TelminB®, 20 mg/lb/day, 3 days) Levamisole (Levasole®, Tramisol®, 10–20 mg/lb) Piperazine (Piperazine-17%®, 1 oz/gal water/l00 birds <6 Mebendazole (TelminB®, 20 mg/lb/day for 3 days) Amprolium in water, 0.12–0.24%/day for 3– days Treat host and environment for 3 days (Coumaphos, 0.% NOTE: Piperazine is the only drug listed here approved for use in poultry. The others have been mentioned in the literature as being useful. Use of these products is recommended only under the supervision of a licensed veterinarian.

Source: http://www.ctahr.hawaii.edu/oc/freepubs/pdf/LM-18.pdf