Steven Clark, DVM

"And it has remained No. 1 since the survey began 16 years ago," said Steven Clark, DVM, Fairmont, Minnesota, and a veterinarian for Devenish Nutrition.

It’s a pattern the US turkey industry knows all too well:

• Dimetridazole, which was extremely effective against blackhead disease (histomoniasis) and once approved for use in turkeys, was banned in 1987.
• In 2005, a New Animal Drug Application was withdrawn for enrofloxacin, leaving the industry with no adequate therapeutic response to colibacillosis or fowl cholera.
• Nitarsone, effective for prevention of blackhead, was withdrawn 31 December 2015.

Other recently lost turkey medications are roxarsone and penicillin-100 Type A medicated feed article, the veterinarian said.

The result: The turkey industry has no effective, FDA-approved medications for blackhead disease, which can result in significant mortality, said Dr Clark, who serves as chairman of the turkey health subcommittee, US Animal Health Association Committee on the Transmissible Diseases of Poultry and Other Avian Species.

"The ability to control and prevent animal disease and/or treat those that are sick is critical to any animal’s wellbeing," Dr Clark told Poultry Health Today. "But increased outside pressure to reduce and even eliminate the use of microbial drugs in animals challenges the industry to develop alternative control measures, including novel nutrition and vaccination and ventilation practices."

Other health issues

The survey results cover experience from August 2015 through August 2016 and are based on responses from 21 veterinarians and other professionals representing the US turkey industry, Dr Clark reported.

A shortage of approved, effective medications has been the top health issue for the US turkey industry for years. Other problems high on the list of health issues cited by respondents in the latest survey include colibacillosis, clostridial dermatitis (cellulitis), Ornithobacterium rhinotracheale (ORT) and leg problems.

Clostridial dermatitis, Dr Clark noted, remains a major disease issue across all geographic regions and is most often seen in commercial male turkeys nearing market age. Mortality in affected flocks is greater than or equal to 0.5 dead per 1,000 birds.

The highly contagious bacterial respiratory disease ORT was a major cause of respiratory disease in Midwestern states in 1995 but has since become endemic across most of the US, he said.

In a previous survey, leg problems ranked No. 10 on the list of health issues but moved up to the No. 5 slot in this most recent survey. They are attributed to a variety of causes including novel reovirus tenosynovitis, pododermatitis, fractured femurs, fractured tibia, osteomyelitis, tibial dyschondroplasia and spondylolisthesis.

Blackhead ranked No. 9, up from No. 13 in a previous survey. The lack of effective, available treatments is especially a concern regarding valuable turkey breeder-candidate flocks, Dr Clark said.

New organic rule

One other important development — one that’s affecting organic turkey production — is the new Organic Livestock and Poultry Practices rule recently issued by the the Agricultural Marketing Service (AMS).

The proposed rule had some worrisome requirements regarding indoor and outdoor space and year-round outdoor access for turkeys as young as 4 weeks of age.

The National Turkey Federation and others in the industry expressed concern that the space requirements would substantially increase land and housing needed, increase the environmental impact and negatively affect production. Requiring outdoor access exposes birds to inclement weather, disease, pests and predation, and could substantially increase mortality. As a result, the AMS final rule eliminated the specific space requirements and won’t require outdoor access until turkeys are fully feathered.

The rule still has several requirements that will affect organic turkey producers. For example, toe clipping must be accomplished with infrared at the hatchery. The rule also addresses artificial-light requirements and confinement in case of a disease outbreak. The new rule was published in the Federal Register and can be accessed here.