Many small farms in Kansas raise turkeys for Thanksgiving and other home use. Kansas also is a major producer of game birds used for restocking programs across the state. Kansas State University often receives calls from producers who describe symptoms of their birds that may be related to Preventing a disease known as Histomoniasis or Blackhead. Although many of the symptoms described by producers are common to a number of diseases, it is likely that a large number of Blackhead these flocks are indeed infected with Blackhead. Most flock owners have heard of this disease; however, few understand Disease in the cause and development of the illness.

Turkeys and Turkeys seem to be most History and Life-cycle susceptible to Blackhead. In There is an old saying that Game Birds fact, Blackhead may be the many producers may be most serious poultry disease familiar with, which is that you R. Scott Beyer confronting the small turkey can’t raise turkeys and chickens Extension Specialist, Poultry Science producer. However, chukkar together. We now know that Animal Sciences and Industry partridge also are susceptible chickens are carriers of several as well as pheasants, quail and J.S. Moritz diseases that can be transmitted other game birds. Graduate Research Assistant to turkeys. Blackhead disease falls under this criterion. Symptoms of Blackhead A milder form of this same It is not unusual for many disease often occurs in chick- producers to note the first ens. Chickens usually do not observation to be an unusually fall ill from this disease, but if high degree of mortality. infected, can potentially Mortality has been reported to contaminate facilities. There- reach up to 70 percent in some fore rearing chickens and flocks. Early signs of this turkeys in the same facility disease may include drowsi- should be avoided. ness, drooping of the head and Blackhead is caused by a wings, walking with an single celled organism Histomo- unusual gait, soiled vent nas meleagridis, which damages feathers due to diarrhea and the cecal wall of the infected bright yellow feces resulting bird and has the potential to from the infection of the liver. damage the liver. This organ- The bird also may become ism can find its way to the bird anorexic leading to a consider- by first being ingested by the able loss of weight and a common earthworm where it depressed, weak appearance. can survive for long periods of Sometimes, the head of the bird time. If infected earthworms appears to be cyanotic, which is are available for flocks of birds a bluish or black discoloration to eat, a Blackhead outbreak of the skin due to deficient becomes a possibility. Once a oxygenation of the blood— bird internalizes the Blackhead hence the name, Blackhead. organism, the organism can The primary lesions of infect a common parasite of the Blackhead develop in the ceca bird’s digestive tract, known as and the liver. These lesions can the cecal worm. Cecal worms Kansas State University promote bloody cecal dis- produce many microscopic Agricultural Experiment Station and charges, which are sometimes eggs that also can be pen- Cooperative Extension Service wrongfully interpreted as a etrated and infected by the symptom of Coccidiosis. Blackhead organism. Cecal

1 worm eggs are shed from numbers and are consumed by the purchase too expensive. infected birds in their drop- turkeys and game birds reared However, some feed mills are pings. It then is possible for on the ground. A 3 to 4 inch willing to purchase this healthy birds as well as earth- layer of crushed limestone additive; checking with a local worms to pick up and ingest covered by dry litter in a feed supplier about its avail- these eggs, thus, becoming ground rearing facility often ability is always a good idea. infected themselves and reduces the prevalence of Also this additive should be perpetuating the disease cycle. Blackhead since earthworms used with extreme caution As with many parasite eggs, usually do not burrow into this since it is extremely toxic to the cecal worm egg is highly type of material. In addition, waterfowl such as ducks and resistant to heat, cold and most manure should not be allowed geese. Currently, Histostat-50 disinfectants. As a result of this to build up in the facility is the only approved medica- resistance, a contaminated because of the concern over tion for use in the treatment of premise remains contaminated transmittance from droppings. Blackhead. Flock owners must for a long time. Reducing the number of cecal keep in mind, however, that worms the birds carry also will Histostat-50 is a preventative Prevention and control reduce risk. Small flock owners medication and is not effective of Blackhead should medicate their flock to in treating flocks already The causative organisms of prevent worms at least annually showing clinical illness. Blackhead cannot survive more with an approved medicine. Although Blackhead can be than minutes without the Once infected, it often is a devastating disease causing presence of a host. Therefore, difficult to eliminate Blackhead high mortality in turkeys and any successful prevention and from a flock. Therefore, game bird flocks, routine control of Blackhead must prevention is the best strategy. prevention strategies can include the elimination of the One medication that can be reduce or eliminate its occur- intermediate host. Because used as a preventative is called rence. For proper diagnoses, a chickens carry many cecal Nitarsone, which also is known diagnostic clinic should be worms, which could be in- by the trade name, Histostat-50 contacted. Any additional fected, rearing chickens away (Alpharma, Fort Lee, New information on the disease can from production turkeys and Jersey). Histostat-50 is a premix be obtained from your local game birds is a good preventa- that can be added to the feed Research and Extension agency. tive measure. Producers should and fed to the birds on a also consider moving facilities to continuous basis up to 5 days References new ground if at all possible. prior to processing or market- Diseases of Poultry, 10th Growing the birds on wire ing. Few local feed mills carry edition, B.W.Clark, editor. will eliminate the bird’s Histostat-50 since they are Acknowledgements: Uni- exposure to earthworms and required to purchase a mini- versity of Nebraska publication fecal droppings. In wet mum amount of the premix number G94-1226-A weather, earthworms often which exceeds the needs of come to the soil surface in large area flock owners and makes

Brand names appearing in this publication are for product identification purposes only. No endorsement is intended, nor is criticism implied of similar products not mentioned. Publications from Kansas State University are available on the World Wide Web at: http://www.oznet.ksu.edu Contents of this publication may be freely reproduced for educational purposes. All other rights reserved. In each case, credit R. Scott Beyer and J.S. Moritz, Preventing Blackhead Disease in Turkeys and Game Birds, Kansas State University, March 2000.

Kansas State University Agricultural Experiment Station and Cooperative Extension Service EP-69 March 2000 It is the policy of Kansas State University Agricultural Experiment Station and Cooperative Extension Service that all persons shall have equal opportunity and access to its educational programs, services, activities, and materials without regard to race, color, religion, national origin, sex, age or disability. Kansas State University is an equal opportunity organization. Issued in furtherance of Cooperative Extension Work, Acts of May 8 and June 30, 1914, as amended. Kansas State University, County Extension Councils, Extension Districts, and United States Department of Agriculture Cooperating, Marc A. Johnson, Director. File Code: Animal Sciences

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