How much ammonia is your litter producing? Wide variations are found between flocks in how much ammonia is released every hour from the litter. In ten week old turkey flocks, moist, composted litter can produce 300 times as much ammonia each hour as dry litter with ample fresh straw added. If the ammonia level in the air exceeds 10 ppm, the turkey’s ability to fight respiratory disease is impaired. Even when the ventilation system is able to keep ammonia levels in the air low, litter which produces high levels of ammonia tends to increase breast blisters due to irritation of the bird’s skin when it sits on the litter. It is important to be able to control both ammonia production and air ammonia levels in your barn to help maintain bird health and carcass quality.

Strategies for Managing Ammonia Production in Your Barn

• Add extra straw once or twice a week after 6 weeks of age
• Build up a 10 cm base of litter
• Use fans and heat to keep the litter below 35% moisture.
• Manage drinkers to reduce spillage.
• Lower barn temperature.
• Use an acid litter treatment to help trap ammonia in the litter moisture.

Carbon and Nitogen Required by Ammonia-Producing Bacteria

The bacteria in turkey litter need a supply of carbon and nitrogen before they can grow and produce ammonia in your barn. As the flock grows older, the manure builds up and the straw breaks down, providing ready sources of these nutrients. If you compost or re-use litter, the ammonia-producing bacteria will multiply at a much earlier age in the flock because the old litter already contains a large supply of available nitrogen and carbon. Higher bird density will also encourage ammonia production as the manure builds up more quickly.

Conflicting Role of Moisture in Producing and Trapping Ammonia

A minimum level of moisture, approximately 30%, is required to support growth of the ammonia-producing bacteria and this growth will accelerate as moisture levels increase from 30% to 40%. In practice, it is very difficult to keep moisture levels below 30% throughout the life of the flock without incurring high ventilation and heating costs or using very low bird densities. Even if you do manage to keep the litter dry, dust levels will increase and cause the airsac damage that you are trying to avoid by controlling ammonia levels. In practice, it should be possible to keep litter moisture in the 30 to 35% range at any location in the barn that is 1.0 m or more away from a drinker. Litter in that moisture range will not be wet but will still stick together if you squeeze it in your hand.

While the role of moisture in increasing ammonia production is well known, its ability to trap ammonia should not be overlooked. Significant quantities of the ammonia produced in the litter become dissolved into the litter moisture, preventing the ammonia from being released as a gas into the air. Litter treatments which acidify or lower the litter pH will increase the amount of ammonia trapped in the litter moisture. The ammonia holding capacity of the litter will provide a temporary buffer against increased ammonia production.

If the litter starts to dry, ammonia trapped in the moisture will be freed as a gas into the air and ammonia will build up in the barn if ventilation rates are not increased. Roto-tilling or turning the litter will also increase ammonia release by exposing the wet, ammonia saturated litter to the air. The litter may need to be tilled twice a week to avoid releasing large quantities of ammonia each time the litter is turned.

The litter in the “donut” or “ring” around the drinker contains 60 to 75% moisture, a level which traps most of the ammonia produced and reduces the activity of the bacteria. The crust which forms on top of the drinker ring also acts as a physical barrier to ammonia release. At a distance of 0.3 to 1.0 m from the drinker ring, ammonia release increases because the moisture level in the litter is high enough to support rapid growth of ammonia-producing bacteria but not high enough to trap all of the gas produced. Producers who move their drinkers on a regular basis to prevent rings from forming will not decrease ammonia production because they are simply redistributing the moisture around a wider area of the barn. Drinker management, which decreases total water spillage, will reduce the total amount of moisture in the barn and lower ammonia production in the litter.

Adding Fresh Litter

Adding fresh litter has an immediate effect on ammonia production because it forms a dry, physical barrier which prevents ammonia release into the air. If new straw is added on a regular basis, ammonia production will be further reduced because the litter will stay drier and the available carbon in the litter will be reduced. The fresh straw has a larger particle size and bacteria have more difficulty extracting carbon from it than the smaller, broken down particles in old litter. A deeper litter base will also encourage water to drain away from the litter surface and help keep the ammonia trapped in the litter pack. Barns where the litter is 10 cm deep or deeper tend to have less ammonia production because of the cumulative effect of the litter addition.

Importance of Barn and Litter Temperature

Dropping the barn air temperature below 18C will cause a noticeable decline in the growth of ammonia-producing bacteria and this decline will continue if temperature is reduced even more. To crudely gauge ammonia production in the litter and to find “hot spots” in the barn, you can measure the temperature 1 cm below the litter surface. After 6 weeks of age, litter that is 27C or higher will likely be producing high levels of ammonia. In a cool barn, (e.g. 15C), the litter will likely be cooler than 27C but any areas where the litter is 5C warmer than the barn air will still be producing significant levels of ammonia. The litter is usually warmer than the barn air because of the heat produced by the litter bacteria.

The Challenges Facing Turkey Growers

 The increasing urban expansion into rural areas creates numerous challenges for livestock producers to various types of farming operations. A strong livestock industry is essential to the nation’s economic stability, the viability of many small rural communities, and the sustainability of a healthful, plentiful and high quality food supply for the American public.

Introduction

Arkansas turkey growers produced 29.5 million turkeys in 2002 ( USDA, 2003), making the state third in turkey production behind North Carolina and Minnesota. As any grower can verify, raising commercial turkeys is no easy task. In comparison to broiler chickens, turkeys are extremely difficult to start, the brooding period is a much more stressful time for both poult and grower, and turkeys remain on the farm for a much longer period increasing the likelihood that something may go wrong before the flock sells. Let’s look at some of the challenges faced by Arkansas turkey growers and how to meet these challenges.

Summertime Temperatures

Turkeys are generally most comfortable when temperatures range from 70-79° F (Anonymous, 2003). Feed intake and growth may be affected as temperatures rise above 80° F and temperatures exceeding 90° F, can result in heat exhaustion or heat prostration. High temperatures are particularly stressful when coupled with high humidity levels.

Heat stress is always a concern of Arkansas turkey producers during summer months and can produce significant losses if growers are not properly prepared. Several factors affect heat production and the turkey’s ability to deal with heat. The digestion of food, the growth process and bird activity all create heat, which the turkey must dissipate (Nixey, ND). As the temperature increases, feed consumption decreases and turkeys begin to pant which negatively affects the performance and profitability of the flock.

A turkey’s first objective is simply to stay alive. Turkeys are warm-blooded and must maintain a relatively uniform body temperature of 105-107°F over a wide range of environmental conditions. If heat produced by the bird is greater than heat that is lost, the bird’s body temperature rises; if it rises 9-11°F and reaches 116° F the turkey dies from heat prostration.

Several methods exist for the turkey to lose heat (Cereno, 1998

How efficiently turkeys can lose heat will depend on air temperature, humidity, air movement over the bird, and stocking density. Turkeys pant to increase the rate of heat loss by evaporative cooling. However, older, heavier birds produce more internal heat and are less able to cool themselves through convection and evaporation. The extra weight might be why higher temperatures are more stressful on toms than hens (Anonymous, 2003). Also, be aware that birds suffering respiratory problems will have a reduced ability to cool themselves through panting. In addition, the more birds in the house, the more heat they generate and they will tend to absorb each other’s radiant heat load.

Air movement (ventilation) is critical if turkeys are to survive summer conditions. Maximize natural ventilation by keeping grass and weeds cut around buildings. Do not park tractors or equipment alongside houses as this restricts air movement through the buildings. You are better off with grass around your houses to absorb heat (if you keep it cut) instead of bare ground because bare ground will reflect heat back into the houses. Make sure your fans are properly maintained.

Keep blades, shutters and safety grills free of dirt and debris. Change fan belts at least once per year. Worn or loose belts can reduce fan efficiency by 20-30 %. Turn fan thermostats down low enough that the fans will run late enough after sundown to give the birds a chance to cool off. Flush water lines regularly to provide cool water to the turkeys; cool water allows the turkey to transfer body heat to the water they drink.

If you have a generator, make sure it is maintained and ready in event of a power failure. If you don’t have a generator, seriously consider purchasing one. They are a somewhat expensive investment if the power stays on, but a generator can pay for itself in one afternoon if the power goes off for an extended period.

Some growers supplement the drinking water with vitamins and electrolytes to reduce heat stress. Vitamins in the water are a good way to insure turkeys are getting what they need during hot weather when feed intake may be reduced. Electrolytes help maintain adequate blood pH which becomes elevated when turkeys pant for extended periods. Always talk to your service technician before starting any supplementation program since they know what works and what doesn’t.

Turkeys normally decrease their activity level and stay away from feeder pans to avoid creating additional internal body heat when the weather is hot. Thus, keeping birds as quiet as possible during the heat of the day and considering an intermittent lighting program to encourage nighttime feeding may help. However, turkeys must be offered a period of complete darkness because it is during this time that the tibia (leg bone) grows at its optimal rate (Monk, 1998). Sprinkling turkeys with water can help fight heat stress when temperatures exceed 80-85°F. However, the amount of water used will vary greatly with condition of the house and the birds and producers should avoid using too much water since it can increase humidity to dangerous levels. Again, consult your service technician before changing your lighting program or starting a sprinkling program.

Pathogen Load

Management programs that will allow turkeys to perform to their genetic potential should be the goal of all producers. Obviously, pathogens can reduce turkey performance and should be controlled. Unfortunately, with the technologies currently available to the industry, complete eradication of the pathogen load in live production is not possible. We can, however, make every attempt to reduce the microbial population through Best Management Practices that include a strict biosecurity program.

Be aware of comings and goings on your farm and make it a rule that no one gets on your farm who doesn’t belong. Feed truck drivers and technical service personnel must have access, but after these folks are accounted for, the list becomes extremely short. Friends, neighbors or other visitors have no vital purpose around your operation and should be excluded. It is up to you to enforce this. You may politely make visitors aware that it is not that you are antisocial, but you have thousand dollars and many hours of “sweat equity” invested in your operation and you cannot afford to have a disease challenge on your farm. Each farm has its own unique microbial population that the turkeys “become accustomed to,” but visitors tend to introduce organisms that are not common to your operation and lead to production or disease troubles. You must minimize traffic flow on your farm, the risk is simply too great to do otherwise. Therefore, take necessary steps to ensure that the only visitors to your farm have a good reason to be there.

The live production process in the turkey industry is a combination of management practices, bird health, the nutrition program and the unique farm environment  Nutrition, like management, must be focused on insuring that the turkey can perform to its genetic potential. Proper bone development is vital in insuring that turkeys achieve their full genetic potential. Any factor that negatively influences bone development will result in stress when the turkey attempts to walk, leading to decreased activity, reduced feed intake, and diminished growth rates (Monk, 1998).

The farm environment directly impacts bird performance. A favorable environment optimizes growth and strengthens the bird’s ability to resist disease. The environment also influences the microbial population unique to each farm. Published research has demonstrated that birds in “clean” environments grew 15% better than those in dirty environments (Fernandez, 1998a). If bird health is compromised, the turkey will likely never reach its genetic potential regardless of your management program. Fernandez (1998b) indicated a vector control program and a clean water supply are also critical to reducing pathogen loads.

Effective rodent control programs involve a rational, systematic baiting procedure, preventive facilities management and constant monitoring. Rodents are often vectors that transmit disease organisms from one flock to the next. Even if facilities are cleaned and disinfected, the presence of rodents can jeopardize sanitation efforts. Darkling beetles are another vector which has been implicated in many poultry diseases.

Beetles have been found to be a source of transmission for Salmonella, Marek’s Disease, E. coli, Infectious Bursal Disease, Newcastle Disease, Clostridium and numerous other diseases (Watkins, 2001). Approved insecticides are available for use after house cleanout for beetle control.

The role of water is certainly underestimated in both turkey and broiler production. High quality drinking water is critical for a healthy environment in both turkey and broiler facilities. Fernandez (1998b) indicated that 45 of 95 (47%) of untreated water samples from various turkey farms were contaminated with bacteria. The most common bacteria found were Pseudomonas, followed by E. coli. Bordetella (which causes turkey coryza). Bordetella has also been isolated from the inside of nipple drinkers and from the rubber seal in the water line regulator in houses with Bordetella-positive turkey flocks (Watkins, 2002). Thus, it is important to reduce the microbial load in the water system by treat water lines during house cleanout, and sanitizing watering equipment during house preparation (Fernandez, 1998b).

Other Challenges

Pathogen load and heat stress are only two of numerous challenges faced by Arkansas turkey growers. Producers must also be alert for coccidiosis which causes economic loss through poor performance and secondary infections. Coccidiosis in turkeys is difficult to diagnose compared to chickens since , in turkeys, visible lesions are rarely seen and an accurate diagnosis requires the use of a microscope. Clinical signs include, weight loss, decreased rate of gain, listlessness, and loose droppings (possibly with blood or mucus), but these are the same symptoms that a variety of other diseases or ailments may exhibit.

The proper house environment during winter is also a major challenge. Houses are usually closed tightly and ventilation is at a minimum during cold weather to conserve fuel. Be aware, however, that adequate ventilation is necessary to guarantee sufficient air exchange, provide needed oxygen, and prevent carbon dioxide (CO2) buildup in the house. Carbon dioxide levels are always a concern in turkey production facilities. In research trials, seven times the normal level of CO2 did not significantly affect livability at 14 days, but average body weights were up to 15% poorer in non-ventilated houses (Fernandez, 1998b). Equally important was the deterioration of bird uniformity that accompanied the depression in weight. Proper winter ventilation is critical if the flock is to perform up to its genetic potential.

Summary

Turkey growers must be constantly vigilant of conditions within the turkey house. High summertime temperatures are always a threat, especially when accompanied with dangerous humidity levels.

Significant costs in lost performance and/or mortality can be expected if measures are not taken to reduce heat stress. Proper winter ventilation is also important to provide an environment that will allow the turkey to perform at its best. Steps must also be taken to control the pathogen load in turkey production facilities. Practice stringent biosecurity and do not allow anyone on your farm unless they have a reason to be there. Monitor bird health and contact your service technician at the first sign of a possible disease outbreak. Turkey production requires that numerous challenges be met along the way to producing a healthy, profitable flock. To be successful, Arkansas turkey producers must meet and overcome these challenges on a daily basis.

References

Anonymous. 2003. Heat stress can be managed. Available at: http://www.cvm.umn.edu/avian/Gob Managingheatstress.html. Accessed March, 2003.

Cereno, T. 1998. Growers have to help turkeys cope with high temperatures. The Feather File. Cuddy Farms. Summer 1998.

Fernandez, D. 1998a. Production performance optimized by reducing pathogen load. The Feather File. Cuddy Farms. Summer 1998.

Fernandez, D. 1998b. Reducing pathogen load optimizes turkeys’ production performance. The Feather File. Fall 1998.

Monk, J. Nutritional, management factors can interfere with development. The Feather File. Cuddy Farms. Fall 1998.

Nixey, C. No Date. Optimising performance in the summer. Available at: http://www.ansci.umn.edu/poultry/ resources/buta-pubs.htm. Accessed March, 2003.

USDA. 2003. Poultry production and value, 2002 Summary. USDA National Agricultural Statistics, Pou 3-1 (03).

Watkins, S. E. 2001. Improving darkling beetle control in poultry facilities. Avian Advice 3(1):14-15.

Watkins, S. E. 2002. The campaign for quality drinking water continues. Avian Advice 4(3):7-9.