It’s no secret that antibiotic-free production presents a variety of challenges to producers with litter being one of the challenges that presents far reaching effects. At the Chicken Marketing Summit, Matt Salois, Chief Economist and Veterinary Economics Division Director, American Veterinary Medical Association, discussed the increased health risks caused by wet litter in antibiotic-free environments.
Eliminating antibiotic use in broilers can lead to increased problems with wet litter, said Salois, which in turn can cause an increase in three significant health risks.
Corneal ammonia burns
The occurrence of ammonia-caused burns to the eyes, and specifically the corneas, are 3.5 times greater in flocks raised without antibiotics according to Salois. The severity of damage depends on the concentration of ammonia and duration of exposure. When ammonia levels reach 50-100 PPM, ammonia dissolves on the eyes to produce ammonium hydroxide. This irritating alkali can cause keratoconjunctivitis. If levels greater than 100 PPM persist, corneal ulceration and blindness may occur. Visible signs of ammonia damage include swollen or red eyelids, and partial or complete closure of the eyes. By the time ammonia levels are high enough to cause blindness, the birds have already lost a significant amount of weight and feed conversion.
Severe footpad lesions
Footpad dermatitis (FPD), or the erosion/ulceration on the bottom of a bird’s foot, occurs 1.4 times more in flocks raised without antibiotics, according to Salois. Most frequently caused by the presence of liquid ammonia on the litter surface, FPD is greatly impacted by the severity and moistness of the litter cake. When birds step on wet litter, it sticks to their feet and the ammonia begins to erode the skin.
The risk of contracting airsacculitis is 1.5 greater in broilers raised without antibiotics as compared to conventionally raised broilers, according to Salois. A serious respiratory condition, airsacculitis is a lower respiratory-associated disease defined as inflammation of one or more of the air sacs. When air sacs become inflamed, they thicken and accumulate caseous material, usually due to a bacterial or fungal infection.
Ammonia is the primary reason birds’ respiratory defenses are breached, which then allow viral and bacterial invaders entrance into their respiratory system. At 25 PPM of ammonia, birds’ cilia will become paralyzed and at 40 PPM the cilia will die off. Ammonia levels of 25-50 PPM can result in reduced body weights, feed efficiency, larger lung size and increased airsacculitis.
Trachea damaged by ammonia
Controlling Ammonia in Antibiotic-Free Operations
The link between ammonia and wet litter, and an increased incidence of footpad lesions, corneal burns and airsacculitis clearly demonstrate the importance of proper litter management and ventilation to control moisture and ammonia.
Quick tips for better litter management:
- Preheat houses 48-96 hours prior to bird placement to dry the bedding, purge ammonia, and warm the floor. Be sure to maintain a relative humidity of 50% to 70% by ventilating as needed otherwise caking will occur.
- Keep litter depth at about 5-8 inches. This will provide sufficient moisture absorbing capacity without being too deep. Litter less than five inches deep often has excessive caking which can lead to high bedding replacement costs. Add an extra inch or two of litter along sidewalls in houses with concrete footers for better insulation. The extra litter will absorb the excess moisture in these high challenge areas.
- Apply PLT® litter treatment to eliminate ammonia prior to bird placement, and reapply mid-flock as needed. An EPA Safer Choice Product, PLT® seeks moisture from the floor to activate and neutralize ammonia.
Facing increased challenges with your antibiotic-free flocks? Schedule a consultation with your Jones-Hamilton representative to learn how litter management best practices can help you address them.