In accordance with the Raised by a Canadian Farmer Animal Care Program, ammonia must be measured, at minimum once weekly starting at week four of grow-out and the measurements must be taken on each floor at bird level using an ammonia monitoring device. If the levels exceed 25 ppm, corrective actions must be taken. Weekly ammonia levels must be recorded in the Flock Specific Record Form along with the corrective actions taken, if any.
It is highly recommended that when ammonia levels exceed 10 ppm, steps should be taken to try to address it to avoid any risk of respiratory damage to the birds. These levels are the national standards set by the NFACC based on available research on the subject.
What is ammonia?
Ammonia is an irritant. It is a colorless, water-soluble alkaline gas that is hazardous to the environment. Ammonia can be found naturally in animal production during breakdown of nitrogenous wastes in animal excrement. Concentrations of ammonia increases as broiler chickens grow and are affected by several factors including litter type, bird activity, stocking density, manure handling and ventilation rate. When present in higher concentrations, ammonia gas is hazardous to workers and the animals.
Potential effects of Ammonia on birds’ health and performance
The impact of ammonia on bird’s health and performance not always easy to measure. Birds can detect ammonia at 5 ppm and health and welfare may be compromised at levels as low as 10 ppm. Concentrations above 25 ppm can cause short-term damage to respiratory systems and feet and can lead to corneal ulcerations. Potential consequences of ammonia exposure depending on the exposure level and duration includes:
- Mild skin irritation
- Decreased feed efficiency
- Reduced weight gain
- Reduced immunoglobulin levels
- Dirty pads or footpad dermatitis
- Compromised ocular health
- Difficulty breathing
- Death
Mitigating ammonia
The goal is to avoid high concentrations of ammonia in the first place and thereby reduce the negative impacts on bird health and performance. Stocking density, ventilation rate, litter management, and temperature adjustments are some management strategies that can be used to control ammonia. Best results can be seen when strategies are used in combination rather than individually.
- The ambient temperature and moisture level of the litter are related to ammonia level in the barn. A rise of 1-2°C can increase ammonia levels, and that effect can be enhanced when combined with rising litter moisture levels.
- Good litter management and ventilation will minimize the level of ammonia, improve productivity, reduce the likelihood of respiratory diseases, improve the birds’ welfare and provide a pleasant, safe environment for workers. It is important to point out that ventilation does not inhibit the formation of ammonia once formation has already begun in the barn. Ventilation is used for barn air quality control where ammonia from the barn is removed and clean air is brought in.
- Research has indicated the potential to reduce ammonia production by treating litter with chemical compounds.
- Environmental conditions, including ammonia, are significantly affected by stocking density. As the stocking density increases with bird age and size, airflow at the bird’s level is often reduced. Ensuring that birds are stocked at the proper density specific to your barn and adjusting ventilation setting according to bird age and external conditions can help in preventing atmospheric ammonia.
Monitoring ammonia
Can I detect ammonia with my nose?
A human nose that has not been exposed to ammonia may be able perceive levels of 10 ppm or above. However, if you have been in the chicken business for a while, your nose likely has been exposed to it for a while. Prolonged or frequent ammonia exposure causes chronic inflammation of the sinuses and olfactory losses. Therefore, relying solely on smell is not sufficient since individual’s sense of smell can become accustomed to the odor. Monitoring ammonia levels using commercially available instruments can help you control it before it reaches significant levels.
Why use Colorimetric paper?
Commercially available ammonia detecting devices include ammonia test paper (colorimetric paper), short and long duration detection tubes, fixed gas detection monitors and portable gas monitors. These devices are manufactured by several companies and can cost as much as $3,500. Colorimetric paper is the least expensive, most accessible and the simplest way of measuring ammonia. Typically, the test strips can detect ammonia between 0-100 ppm. They are designed and calibrated to detect ammonia at trace levels. Within 15 seconds of a moist strip of paper being exposed to air, ammonia level can be determined. The test strips do not need to re-calibrated upon purchase given proper procedures for storage is followed.
While you may not be able to get an exact value for the ammonia level in the barn, the accuracy of the range provided should not be questioned. Knowing the range of ammonia present in the barn will be beneficial in figuring out the next steps in controlling ammonia. As indicated earlier it is a requirement to explore techniques to reduce ammonia once it is measuring above 25 ppm.
With the use of colorimetric paper, you can keep track of ammonia levels and take action prior to reaching that high-risk level. Since most brands of colorimetric paper are unable to differentiate ammonia between 20 ppm and 25 ppm or 20 ppm and 50 ppm, it is important take action at 20 ppm readings. By utilizing proper technology for routine monitoring of ammonia you can provide birds the best environment for production and welfare.
