Blackhead disease also known as histomoniasis is a common parasitic infection that affects turkeys and other poultry. It is caused by the microscopic protozoan Histomonas meleagridis. This disease can result in serious health complications and even death in infected birds. But an important question that emerges is – can you still eat the meat from a turkey infected with blackhead disease? Let’s find out.
Understanding Blackhead Disease in Turkeys
Blackhead disease gets its name from the darkened head and neck region seen in some infected turkeys. The disease typically spreads through the ingestion of H. meleagridis eggs that are shed in the droppings of carrier birds like chickens and pheasants. Earthworms can also transmit the infection by ingesting the eggs and then being eaten by susceptible turkeys.
Once inside the bird, H meleagridis invades the ceca and liver, causing severe inflammation and necrosis Infected turkeys exhibit symptoms like listlessness, diarrhea, weight loss, droopiness and yellowish droppings. The disease progresses rapidly and results in death within 2-4 weeks in acute cases. Morbidity and mortality rates in turkey flocks can be as high as 100% and 70% respectively.
Can You Eat the Meat of an Infected Turkey?
The concerning aspect about blackhead disease is that H. meleagridis can be transmitted to humans through consumption of raw or undercooked meat from infected turkeys. This can lead to a condition called human histomoniasis which causes nausea, vomiting, diarrhea, and liver enlargement.
So should you eat a turkey with blackhead disease? The short answer is no, you should avoid eating the meat of a turkey infected with blackhead disease. Even though thorough cooking can destroy the parasite, the weakened health of the infected bird makes the meat quality poor. Moreover, there is still a risk of cross-contamination with the raw infected meat in the kitchen.
The U.S. Department of Agriculture advises against selling turkey meat from flocks infected with blackhead disease. From a safety standpoint, it is best not to take a chance with infected meat.
Other Concerns with Consuming Infected Turkey Meat
Here are some other important reasons why consumption of blackhead infected turkey meat should be avoided:
- The H. meleagridis parasite can penetrate deep into the liver and muscles of infected turkeys. So cooking may not eliminate the risk fully.
- Infected birds are immunocompromised and prone to secondary bacterial infections like E. coli and Salmonella. These can also be transmitted through undercooked meat.
- The weakened infected birds have very little muscle mass and fat. So the meat quality and quantity is very poor.
- Cross-contamination risks are high during raw meat handling in the kitchen. This can lead to inadvertent ingestion of the parasite.
- Even cooked infected meat may retain a rubbery and unpalatable texture and rancid taste. The overall eating experience will be unpleasant.
- Why take the health risk when so many disease-free turkey options are easily available? Better to be safe than sorry.
So the consensus is clear among food safety experts. Consuming blackhead infected turkey meat is an unnecessary health risk that is best avoided. The wise approach is to only buy and eat turkey meat from reputable sources that follow good biosecurity practices. Preferably, inspect the farm yourself before purchasing the birds.
How to Prevent Blackhead Disease in Turkeys
Since treatment of blackhead disease is very difficult, prevention is the best approach for turkey farmers. Here are some tips:
- Maintain an all-in, all-out turkey flock. Avoid mixing birds of different ages.
- Keep chickens, which are carriers, away from turkeys.
- Follow strict biosecurity protocols. Restrict outsider access to the farm.
- Provide turkeys with optimally balanced feed and clean drinking water.
- Reduce stress through proper ventilation, temperature control and low stocking density.
- Follow an effective sanitation routine. Remove droppings and litter frequently.
- Incorporate antioxidants like vitamin E in feed to support immunity.
- Use anticoccidials like amprolium in the feed for the first 14 weeks.
- Consult a vet at the first sign of the disease for advice and testing.
- Immediately isolate and euthanize sick birds showing symptoms to prevent spread.
With sound biosecurity and management practices, blackhead disease can be kept at bay. This ensures healthy turkeys and safe meat for human consumption.
FAQs Related to Blackhead Disease and Turkey Meat Consumption
Here are answers to some common queries on consuming meat from blackhead infected turkeys:
Is it safe to eat the eggs from an infected turkey?
No, eggs from infected turkeys can also transmit the H. meleagridis parasite. Avoid consumption.
Can you eat a turkey that survived blackhead disease?
Recovered birds can still carry H. meleagridis. So it is best not to consume the meat.
What if I cook the infected meat well?
Thorough cooking kills the parasite but does not eliminate the risks fully. Avoid eating such meat.
Is blackhead disease meat safe for dogs?
No, the parasite can also infect dogs if they consume raw infected meat. Cooked meat may be safer.
Can I tell by looking if a turkey has blackhead disease?
Not necessarily. Infected birds may not always show symptoms externally. Internal lesions are seen upon necropsy.
Is there a vaccine available for blackhead disease?
Unfortunately there is no effective commercial vaccine yet. Following preventive measures is critical.
Does freezing kill the H. meleagridis parasite?
Freezing may reduce parasite counts but does not completely eliminate the infection risk.
What temperature kills the blackhead organism?
The H. meleagridis organism can be killed by cooking the meat to an internal temperature of 165°F (74°C).
How long can the parasite survive in infected meat?
The parasite can survive for several weeks in moist infected meat stored at 40–50°F (4-10°C).
Should I avoid eating turkey altogether?
No, only avoid meat from flocks infected with blackhead disease. Purchase turkeys from reputable disease-free sources.
The Takeaway on Eating Turkey with Blackhead Disease
Blackhead disease in turkeys poses a genuine risk of transmission to humans through consumption of infected meat. The wise approach is to play it safe and avoid eating meat from turkeys showing any symptoms of this disease. Prevention is the best cure, so turkey farmers should follow rigorous biosecurity protocols and maintain optimal bird health through proper care and nutrition. As a consumer, only purchase turkey meat from trusted sources with ensured health standards. With some care and caution, we can enjoy delicious and nutritious turkey on the table without worries.
What is FDA doing about the lack of approved drugs against blackhead disease in poultry?
The National Turkey Federation asked FDA to determine if controlling blackhead disease in turkeys qualifies as a “minor use in a major species.” Based on information provided to the agency by the federation and on information from other references, FDA’s Office of Minor Use and Minor Species Animal Drug Development determined that using a drug to control mortality caused by blackhead disease in flocks of turkeys diagnosed with the disease qualifies as a minor use. Because of this assessment, any drug company or other group that is pursuing an approval of a new animal drug for this specific use is entitled to various incentives, including user fee waivers, grants, exclusive marketing rights, and eligibility for conditional approval.
Lifecycle and Signs of Disease
The lifecycle of the protozoa H. meleagridis is complex:
- The protozoa multiply in an infected bird’s cecum, a part of its digestive tract;
- They move to the bird’s intestines where the roundworm H. gallinarum lives;
- The roundworm eats the protozoa;
- The roundworm’s eggs become infected with the protozoa;
- The bird sheds the protozoal-infected roundworm eggs in its droppings.
Healthy birds become infected when they eat food, invertebrates (such as earthworms), or bird droppings that are contaminated with the protozoa. Direct bird-to-bird transmission can also occur within a flock. Because chickens, partridges, and pheasants commonly have the roundworm in their intestines, they often are the source of the protozoal infection for other birds.
Birds with blackhead disease are usually listless and have drooping wings, unkempt feathers, and yellow droppings. Typically, the cecum and liver of an infected bird will become inflamed and develop ulcers. Young birds become sick quickly and usually die within a few days after signs appear. The disease develops more slowly in older birds and they often become emaciated and may eventually die.
Turkeys are highly susceptible to blackhead disease. Once a turkey flock has been infected, 70 to 100% of the birds may die. In one survey, U.S. turkey industry professionals reported at least 50 outbreaks of the disease each year since 2009.1 Blackhead disease is less severe in chickens but can lead to poor health and reduced egg production.
Histostat (nitarsone), an arsenic-based animal drug, was the only FDA-approved drug to prevent blackhead disease in poultry. But in 2015, the drug company voluntarily stopped marketing Histostat and asked FDA to withdraw the drug’s approval due to concerns about inorganic arsenic levels in birds treated with the drug. Currently, there are no animal drugs approved to prevent, treat, or control blackhead disease in the U.S.
More Information on the withdrawal of Histostat (nitarsone):