The lack of effective treatments for persistent diseases continues to be the largest health issue facing the turkey industry, according to National Turkey Federation research.
The research was presented in an October 2018 report written by Dr. Steven Clark, a poultry veterinarian with Devenish Nutrition, and Victoria Ahlmeyer, scientific and regulatory affairs coordinator for the NTF. For the 2018 edition of this report, a total of 24 turkey industry professionals and veterinarians were surveyed about the health of turkeys raised between August 2017 and August 2018.
The annual survey helps establish which health and industry issues are seen as the most important. The largest concerns for turkey health in 2018 were similar to the 2017 findings except that blackhead fell to number 11 from number 8 on the list. In spite of this, the number of reported cases of the disease increased by 15 percent during the survey period.
The report said the top 10 most critical issues are: lack of efficacious drugs, colibacillosis, ORT, coccidiosis, cellulitis, Bordatella, Salmonella, poult enteritis of unknown etiologies, leg problems and cholera. Going forward, Clark said the industry’s key research needs to center on blackhead, turkey reovirus, also known as TR-DFTR, and ORT.
With antibiotics falling out of favor, more turkey producers are turning to alternative treatment methods. | Photo by Austin Alonzo
1. Lack of approved, efficacious drugs
The turkey industry continues to deal with a shortage of drugs to treat its most serious diseases and this continues to be the top concern of the industry’s health professionals. Turkey is already disadvantaged due to its size compared to other animal protein industries and other economic factors surrounding drug development. The continuing reduction of antibiotic use due to antibiotic-free (ABF) or no-antibiotics-ever (NAE) growing programs and the veterinary feed directive (VFD) is further limiting the options for disease treatment.
The report said the industry is without adequate therapeutic responses to colibacillosis or fowl cholera due to the unavailability of enrofloxacin. It also mentioned the unavailability of the drugs roxarsone, penicillin-100 type A medicated article and nitarsone. Along with the aforementioned diseases, the report said the industry lacks drugs for ORT, clostridial dermatitis, coccidiosis, Bordetella and Salmonella.
2. Colibacillosis
Colibacillosis, a disease caused by an infection of Escherichia coli, ranked as the second largest health concern among the turkey industry. Since the 2005 withdrawal of the New Animal Drug Application (NADA) for enrofloxacin, the poultry industry has not had a therapeutic response to the disease.
3. ORT
ORT is a highly contagious respiratory disease caused by the bacteria Ornithobacterium rhinotracheale. The disease originates in Europe and South Africa. The first case was confirmed in the U.S. in 1993 and, in 1995, it spread around the Midwest, causing a major respiratory health problems. Since then, it’s become endemic to most of the country.
Management systems, like brood-and-move, can increase exposure to ORT in finisher barns. Biosecurity measures and sanitation can help control the severity and spread of the disease. Vaccination options against the disease are limited – no commercial vaccine is approved – and the results of vaccination are varied. Controlled exposure efforts on individual flocks show some value in recent research.
Going forward, ORT is classified as a critical research need. Currently, genomic research of the bacteria is underway that could help in the development of effective vaccination options for individual farms.
4. Coccidiosis
Coccidiosis continues to elevate in concern, it was ranked as 6 on this list in 2017 and 13 in 2016, as the industry’s adoption of ABF and NAE programs grows. These programs don’t allow ionophore anticoccidials and many programs prohibit chemical anticoccidials as well, so the current programs rely on vaccinations or alternative treatment options.
According to the survey, ionophores still represent the majority of coccidia control programs. The report said 44 percent of the survey respondents used ionophores for part of the 12 month survey period. The level of ionophore use dropped by 11 percent, from 55 percent in the 2017 report, in the 2018 findings. Chemical anticoccidials accounted for 30 percent and coccidia vaccination for 10 percent of treatment strategies, respectively.
Adoption of alternative treatments to control coccidia doubled compared to the previous year. Alternatives, called phytonutrients in the report, were used for coccidia control by 28 percent of those surveyed. In 2017, 14 percent used alternatives. Thesee treatments may be used in addition to other coccidia control measures or as the sole supplement for coccidia control. Phytonutrients include plant extracts, prebiotics and essential oils.
5. Clostridial dermatitis
The disease, also called Cellulitis, is most commonly seen in commercial male turkeys nearing market age but is not limited to those birds. An affected flock can experience mortality greater than or equal to 0.5 dead per 1,000 birds for two, consecutive 24 hour periods. There’s disagreement about the risk factors and potential causes of the problem, but there’s some limited success with vaccinating at-risk flocks with autogenous bacterins and toxoids.
The report said the best ways to control the disease are:
- Early recognition
- Removal of mortality two or three times a day
- Medicating affected flocks with appropriate antimicrobials
- Promptly managing all water spills, wet litter and feed outages
- Avoiding composting litter within 200 feet of the poultry barn
Turkey producers are dogged by the lack of effective drugs to treat challenging diseases. | Photo by Austin Alonzo
6. Bordetella
Bordetella avium is a highly contagious respiratory disease caused by a species of the Bordetella bacteria. The disease is a significant challenge in several regions of the country and is magnified by limitations of antibiotics usage.
Birds between two weeks and eight weeks of age are most severely affected by the disease. When the disease is present, 80 to 100 percent of the flock may experience clinical signs. Associated mortality is between 2 and 5 percent and can be as high as 10 percent in complicated cases.
Bordetella can be controlled with sanitation of drinking water, ventilation and biosecurity.
7. Salmonella
Salmonella, a bacteria pervasive among the poultry industry alongside Campylobacter and Clostridium perfringens, is widely recognized as a health issue in the industry but not a severe problem. Food is the primary source of these infections, so the poultry industry is constantly working to contain foodborne illnesses caused by the bacteria. The U.S. Centers for Disease Control and Prevention estimates Salmonella causes about 1.2 million illnesses, 23,000 hospitalizations and 450 deaths in the U.S. annually.
8. Poult Enteritis of unknown etiologies
Poult enteritis of unknown etiologies rose to 8 from 10 in the 2018 survey of industry concerns. As a disease of unknown etiology, the enteric disease can come from a variety of bacterial or viral sources. It affects the intestines of young turkeys. By comparison, the report said, turkey coronavirus – a defined cause of enteritis – ranked 30 out of the 36 diseases included in the survey.
9. Leg problems
Leg problems include a number of conditions – such as spiral fractures of the tibia or femur and lameness – and can be caused by disorders like pododermatitis, fractured femurs, fractured tibia, osteomyelitis, tibial dyschondroplasia, spondylolisthesis and so-called Shaky Leg syndrome.
The year 2017 saw an increase in the incidence of valgus and varus leg deformities, which contributed to increased mortality in affected flocks. The cause of those conditions is not determined. These issues were less prevalent in 2018.
10. Cholera
Fowl cholera is a highly contagious disease caused by Pasteurella bacteria which can affect avian species including turkeys. The disease is typically treated with antibiotics, so a reduction of their use may play a role in the disease challenge.
In an interview, Clark said the survey data showed the disease was an isolated, regional issue rather than a widespread challenge during the survey period. He said cholera prevention depends upon biosecurity measures such as the control of rodents and pests coming onto the farm and into the production areas.
The survey, covering market conditions from August 2017 through August 2018, asked turkey industry professionals to use a 1-5 rating system to describe how concerned they are with disease challenges.
US turkey production up in 2017
According to National Turkey Federation research, U.S. turkey production increased slightly in 2017, to 7.495 billion pounds live weight from 7.487 billion pounds live weight the prior year. Conversely, per capita turkey consumption fell to 16.4 pounds in 2017 from 16.5 pounds the prior year.
Additionally, live production in 2017 decreased to 242.5 million head, from 243.3 million head. Average live weight in 2017 was 30.92 pounds, compared to 30.7 pounds the prior year.
Read more:
2 new microbial treatments to improve animal health, www.wattagnet.com/articles/35210
