Tackling Ammonia Buildup in Poultry Litter?

In poultry farming, a major social concern—besides flies—is the strong manure odor caused by ammonia buildup. Ammonia is an invisible, pungent, water-soluble gas released during the decomposition of droppings and urine. In summer higher temperatures increase microbial activity in the litter, speeding up the breakdown of uric acid and urea, which produces more ammonia. High levels not only create foul smells but pose serious health risks to both birds and workers, contributing to respiratory issues, dermatitis, foot burns, gastrointestinal irritation, and ascites. Reducing ammonia emissions significantly improves overall flock and human health.

Ammonia’s Impact on Poultry and Humans

About 70–80% of dietary nitrogen is excreted, with uric acid being the major form, later converted to ammonia via urease enzymes in the presence of moisture and oxygen.

Ammonia and ammonium exist in equilibrium, influenced by litter pH—lower pH favors ammonium, which stays in the litter, while higher pH promotes ammonia gas release. Factors like litter pH, temperature, and moisture affect this balance. For instance, a 5% increase in moisture (from 20% to 25% at 75°F) can cause a 140% rise in ammonia levels. Factors like poor litter management, high humidity, overcrowding, and inadequate ventilation exacerbate emissions.

Ammonia is water-soluble and easily absorbed through the eyes, skin, and respiratory tract, posing health risks. Poor litter management, high humidity, overcrowding, and inadequate ventilation lead to wet litter and increased ammonia release. Other contributing factors include litter type, bird activity, manure handling, and removal frequency.

Ammonia, poultry health and performance

According to OSHA, humans can detect ammonia at 5 ppm, with a safe exposure limit of 50 ppm over 8 hours. In poultry houses, experts recommend keeping levels below 25 ppm, ideally under 10 ppm. Prolonged exposure can cause chronic respiratory issues like bronchitis and asthma in humans.

In poultry, high ammonia levels (20–25 ppm and above) lead to poor performance, increased disease risk, and economic loss. Ammonia irritates the eyes and respiratory system, forming corrosive ammonium hydroxide on moist tissues, which damages tracheal linings, destroys cilia, and allows bacterial infections like E. coli to reach the lungs.

Birds exposed to ammonia may show signs like labored breathing, conjunctivitis, air sac inflammation, and weakened immunity. Chronic exposure reduces feed intake, growth, egg production, and vaccine response. It also damages gut lining, affecting nutrient absorption and increasing vulnerability to oxidative stress.

Common Clinical Signs:

• Eye irritation, conjunctivitis, and corneal damage
• Swelling and reddening of eyelids, conjunctiva, and nictitating membrane
• Almond-shaped eyes in affected birds
• Increased risk of Swollen Head Syndrome during viral respiratory infections

Ammonia Blindness:

• Characterized by cloudiness, opacity, and eventual blindness
• Often accompanied by eye discharge, squinting, and redness
• Caused by ammonia fumes from wet litter and poor ventilation
• Blind birds struggle to find food, water, and navigate social interactions

20 – 30 ppm: No drop in egg production and weight loss. Slight respiratory lesions.

50 – 60 ppm: No change in egg production, lower feed intake, weight loss, respiratory and eye lesions visible.

100 – 200 ppm: Reduce egg production, severe weight loss, ammonia blindness (kerato-conjunctivitis), loss of cilia from respiratory epithelium, increased number of mucus secreting cells, haemorrhages in trachea and bronchi. Heart rate and breathing are affected.

Measure ammonia in poultry houses

• Chemical test kits: Inexpensive, quick, but not continuous.
• Gas sensors/meters: Accurate, real-time, but costly and require maintenance.
• Electronic nose technology: Fast, sensitive VOC detection.
• Colorimetric detector tubes: Easy and fairly accurate.

Mitigation Strategies

1. Nutritional Management
   • Use amino acid-based formulations instead of crude protein.
   • Inculcation of Yucca schidigera in the formuation as a feed additive
   • Lower dietary protein by 3–5% to reduce nitrogen excretion and water intake.
   • Add dietary fibre (e.g., soy hulls, wheat middlings) to shift nitrogen excretion and lower manure pH.
   • Use feed additives like zeolite, bentonite, diatomaceous earth, and Yucca extracts to bind or reduce ammonia.
2. Litter and Environmental Control
   • Maintain litter moisture at 20–25%.
   • Apply treatments like sodium bisulfate, alum, or zinc sulfate to reduce pH and microbial activity.
   • Use organic acids (citric, tartaric, salicylic) to acidify litter and suppress pathogens.
   • Ensure proper ventilation to reduce humidity and dry litter.
   • Compost litter to retain nutrients and reduce ammonia loss.
3. Operational Practices
   • Prevent feed/water waste to reduce nutrient-rich excreta.
   • Provide adequate floor space to prevent wet litter.
   • Use enzymes, probiotics, and prebiotics to improve gut health and nutrient absorption.