Zootecnica International - World Poultry Journal

¹DVM, ACPV
Keck and Associates, Inc, West Fork, AR
²National Center for Appropriate Technology
University of Arkansas
Poultry Science Department, Fayetteville, AR
U.S.A.

Organic and natural poultry production has been growing in the U.S. for the past decade and is now the fastest growing sector in the poultry industry. In some ways, it is a return to principles used many years ago before the advent of intensified rearing, pharmaceutical products, pesticides, and other chemical agents used to control disease or kill microorganisms. The organic poultry market has grown due to concern about chemical residues, animal welfare, and sustainable agriculture beliefs.
Organic and natural poultry, antibiotic-free, and other types of production may differ in their goals but all tend to have features that are common to all types of poultry production, including conventional. Many of the present antibiotic feed usages in poultry continue to decline due to voluntary or regulatory reductions. As a consequence, there has been increased emphasis placed on the development of alternative specialized production practices, which would eliminate and/or reduce the use of antimicrobials while maintaining health and comfort.
Organic production must rely strongly on biosecurity and excellent management practices since reliance on antibiotics, anticoccidials, growth promotants and synthetic chemicals is not permitted. Alternative strategies must consider factors such as animal management, nutrition, feed additives, disease eradication, genetics, vaccines, etc. Producers are encouraged to explore new and emerging technologies that reduce synthetic chemical dependence (e.g. probiotics help by competitive exclusion).

Organic poultry health management is based on prevention

It is important to:

• Prevent the introduction of diseases by proper biosecurity and sanitation to minimize the disease level. Biosecurity encompasses the measures that are used to prevent the introduction of diseases and procedures used to contain or prevent spread when diseases occur.
• Reduce stress to improve the immune status. This includes good management, temperature, adequate spacing, proper ventilation and litter conditions, good nutrition, and clean water/feed for the birds. It may also include natural intervention strategies such as the use of prebiotics, probiotics, and competitive exclusion to alleviate severe GI problems such as Necrotic enteritis and Coccidiosis. Maintaining a normal healthy gastro intestinal (GI) system is a vital component of organic production.
• Vaccinate to prevent infectious diseases when necessary.

Treatment is used only as a last resort

Unique aspects of organic poultry production include the USDA National Organic Program standards that do not permit synthetic drugs. Treatment cannot be withheld if needed, however, and birds should be removed from the organic program after treatment. Outdoor access is required in organic production, but production systems vary, often depending on the size of the operation. Large operations usually use stationary houses with fixed yards while small operations use portable housing. It is important to rotate pastures for optimal disease control. Many organic producers are small, independent producers who often have different species and ages of poultry on the same farm. Ducks, geese, and turkeys may be carriers of diseases that affect chickens and vice versa. Likewise older birds may be carriers of disease that can be detrimental to younger birds with less developed immune systems.
The prevention of predation is basic to protecting bird health. Ground predators such as skunks and opossums can be excluded with adequate fencing. Because many predators will dig, a wire skirt around the fence is useful. Fencing may be permanent or portable. Portable electronet fencing is particularly effective in excluding ground predators and is available with a tight mesh at the bottom. Because many ground predators are nocturnal, enclosing birds in secure poultry housing will protect them at night. Stray dogs roam in the day and are particularly problematic during daytime hours. Overhead predators such as hawks and owls are problematic but can be excluded by netting over the yards. Instead of netting, some small producers string filaments or threads across yards to interfere with the stealth hunting of hawks. Adequate hiding places such as bushes or overhangs help chickens escape. Other producers use scare tactics such as flashing lights.
Biosecurity is crucial in preventing the introduction of disease and one of the main aspects is the concept of isolation. The poultry house should be in a location isolated from other poultry and access to it should be restricted. Only necessary visitors such as vets should be permitted. Visitors should not have been around other poultry or should have showered and changed clothes. Young birds should be cared for before any older birds to prevent the introduction of disease to young birds. Only clean birds should be purchased, preferably day-olds from hatcheries approved by the National Poultry Improvement Plan (NPIP). Sanitation is crucial. Prevent the introduction of pathogens into a poultry house by using a footbath with disinfectant. Vehicles and other equipment must also be sanitized with a spray before entering the farm, particularly vehicles that visit other farms such as fed trucks or gas delivery trucks. Physical washing with a detergent removes the soil and most of the pathogens. Then any remaining microbes should be killed with a sanitizer such as chlorine bleach. Organic matter such as soil will render the disinfectant much less effective. Sunlight (UV) is also a useful disinfectant and the process of drying slows biological activity and kills many pathogens. It is important to completely depopulate poultry farms regularly. "All-in, all-out" practices result in the destruction of many pathogens that only thrive around live poultry. "Dilution is the solution to pollution" is a common saying in biosecurity and health management. Carcasses should be disposed of by a proper method such as incineration or composting.
Vaccination programs are an important way to prevent disease. For broilers (meat birds), vaccination is recommended for Newcastle, Infectious Bronchitis, and Infectious Bursal Disease. These should be administered at hatch and/or at 10-14 days of age. Some producers also vaccinate for Salmonella, especially if their customers require it. For broiler breeders and layers, a combination of modified live vaccines is used, followed by injectable inactivated vaccines. Turkey vaccination programs are best customized. It should be noted by those who purchase day-old chicks that many hatcheries routinely inject chicks with antibiotics. Confer with the hatchery manager if you do not want these antibiotics given.
Major poultry diseases include:

• Respiratory: Newcastle, Infectious Bronchitis
• Immunosuppressive: Infectious Bursal Disease
• Intestinal: Necrotic Enteritis, Coccidiosis.

Producers should learn to recognize signs of these diseases. Necropsy of dead or sick poultry can provide valuable information. For example, the size of the bursal gland indicates the presence of immunosuppressive disease.
Organically-raised poultry have specific health concerns due to outdoor access, particularly from contact with wildlife. Birds may contact fowl cholera (Pasturella multocida), salmonella from skunks and raccoons, and fowl pox from wild turkeys and pigeons. Organic birds may also contact avian influenza from waterfowl, which are carriers. Avian influenza (AI) may be in a highly pathogenic form (high-path) or a low-path form. Low-path AI is endemic in the live bird market on the east coast.
Routine medication may not be used to control coccidiosis in organic production. Management focuses on reducing the number of coccidia to keep infection at a minimum until immunity is established. In low-density, small-scale production, the birds tend to stay ahead of the parasites and may not require medication. Keep litter dry and brooding areas clean. It is important to control areas of high traffic outdoors to reduce the number of oocysts or coccidia eggs. The location of the waterer and feeder should be rotated; the yard should also be rotated. Many organic producers use vaccines such as Coccivac® to control coccidiosis.
Biosecurity information is available on the Internet and from other sources.
See http://animalscience.ucdavis.edu/Avian/Biosecsmfl.pdf and http://www.aphis.usda.gov/vs/birdbiosecurity/.
Necrotic enteritis is a disease of the gut caused by the bacteria Clostridium perfringens and has high mortality. In the conventional poultry industry, it has traditionally been controlled by adding antibiotics to the feed. Since routine antibiotics are being removed in the conventional industry and are not permitted in organic production, necrotic enteritis has been a problem for large-scale producers and methods of replacing antibiotics have been a focus. Methods include feed conditioning and competitive exclusion. Feed can be a source of pathogens, so feed should be properly treated or conditioned to ensure any pathogens are killed. Organic acids are moderately effective in replacing antibiotics. Competitive exclusion is a method in which beneficial microbes outcompete pathogenic bacteria in the gut and improve the health status of the host. The inoculation of young chicks with gut bacteria obtained from healthy disease free adult chickens enhances the resistance of the young chick to colonization by pathogens. Probiotics are cultures of desirable, beneficial live microorganisms which, when added to the diet, improve the balance of indigenous microflora, thereby promoting the health of the host. Probiotics change (increase) the rate of volatile fatty acid (VFA) (butyric or propionic acid); some mechanisms of action are not understood, but they alter normal gut flora.
An example of probiotics is the lactobacillus species in the product FMB-11. These microbes share the same niche in the gut as Clostridium perfringens and can outcompete them. This product was developed at the University of Arkansas where research indicated that other products were low in live organisms or sterile. FMB-11 performs as well or better than antibiotics and costs less. FMB-11 has been successful in curbing an outbreak of necrotic enteritis in one antibiotic-free company, reducing mortalities from 400 per day to 36 in just 72 hours. These bacteria perform even better when used with a "prebiotic" such as lactose (fed at 0.1% of the diet). FMB-11 is available from Wynco/Iowa Vets and is in the process of becoming OMRI-listed.
Prebiotics have been defined as "non-digested food ingredients that beneficially affect the host by stimulating the growth and activity of one or a limited number of bacterial species already residing in the large intestine". A prebiotic would ideally alter the microbial balance such that the potentially beneficial microorganisms become predominant. Oligosaccharides, a type of prebiotics, are complex carbohydrates poorly digested by higher animals but utilized as substrates by beneficial microorganisms.
Food safety is a concern with organic poultry products as well as conventional and food-born pathogens such as salmonella, campylobacter, and E. coli can cause problems.
Additional health problems in organic poultry production include feather-pecking and cannibalism, especially in layer flocks, and parasitism. Feather pecking has both genetic and environmental causes. While geneticists select for birds that do not have the feather-pecking trait, environmental causes are not completely understood. It may be a misdirected behavior. Natural levels of lighting used in organic production may encourage it. Internal parasites such as roundworms can be particularly problematic because there are few organic controls. Pasture rotation will help reduce parasitism. External parasites, such as mites and lice, can be controlled by a management focus and pyrethrin products. Sulfur powder was effective against external parasites in the past.
Alternative natural treatments for disease will continue to be of interest in organic production. For example organic selenium acts as an immune enhancer and antioxidant. Botanicals such as garlic, oregano, and rosemary may hold potential.
Additional details for proper sanitation on organic poultry farms are useful. Bleach can be used at a 1:32 dilution in footbaths or in cleaning. Iodine can also be used. Water lines should be cleaned with organic acids, vinegar, and hydrogen peroxide. A 3-step process is used: remove debris from inside the pipe and nipple with an acid; drain the debris that has broken loose by flushing, and add a sanitizer or disinfectant such as chlorine to prevent bacteria from growing. Chlorine can be included in drinking water only at drinking water levels. Rodents should be excluded from facilities to prevent the introduction of diseases. Forage should be kept short and feed spills cleaned. Sticky traps or bait traps with toxic levels of vitamins can be used.
Additional preventative practices for organic poultry health management include testing the feed for aflatoxin. Levels should be less than 20 ppb. Blood should be drawn from birds at processing to monitor for respiratory diseases. Diagnostic labs can run these tests. Mortality rate for broilers should be less than 5%.
Producers should work closely with an avian vet and should develop a health management plan. The Association of Avian Vets (www.aav.org) can help locate an avian vet. Small operations without a vet should work with state diagnostic labs for health monitoring and to develop a health management plan. A list of state diagnostic labs is provided at the website of the National Poultry Improvement Plan http://www.aphis.usda.gov/vs/npip/.

References

• National Organic Program: www.ams.usda.gov/nop/ http://www.organic-vet.reading.ac.uk
• Feed Management. March 2003. Vol. 54, No. 3. Page 18. Shipp and Madsen (www.feedindustrynetwork.com)
• Wikon, JLS. Raising antibiotic-free poultry. Poultry Digest On-Line Vol 3, No. 11.
• Bedford, Michael R. and Andrew Fotherfill. No date. Alternatives to antibiotics: Nutritional strategies to manage microfloral population. Eastern Nutrition Conference.
• Guoe, F.C. et al. 2003. Immunoactive, medicinal properties of mushroom and herb polysaccharides and their potential use in chicken diets. World's Poultry Science Journal. Vol. 59, No. 4.
• Food Safety:
• Magkos, Faidon, Fotini Arvaniti and Antonis Zampelas. 2003. Putting the safety of organic food into perspective. Nutrition Research Reviews. Vol. 16. P. 211-221.
• Biosecurity http://www.aphis.usda.gov/vs/birdbiosecurity/
• Probiotics
• Estrada, A. et al. 2001. Administration of Bifidobacterium bifidum to broilers reduces the number of carcass condemnations for cellulitis at the abattoir. Journal of Applied Poultry Research. Vol. 10, page 329-334.

From Proceedings of the "Midwest Poultry Federation Convention", St. Paul, Minnesota, U.S.A.