Researchers have examined how natural zeolites can be applied in barns and feedlots to combat odors and reduce ammonia levels. Odors emitted from these environments often result from ammonia and sulfur compounds that generate from manure handling or storage facilities (Lemay, 1999). Ammonia poses additional challenges because of the stress and irritation it causes to reparatory tracts and mucous membranes, both of which can compromise the overall health of livestock, horses, and poultry (Ullman et al., 2004).
A study by Mumpton (1985) found that spreading 25 tons of zeolite per month on the floors of a swine- raising facility absorbed excess liquid waste and reduced the moisture content of excrement. Buildings were described as dry, clean, and significantly less odorous.
Koelliker et al. examined the use of zeolite in poultry houses to reduce ammonia concentrations in the air. Essentially, the researchers constructed a device that allowed them to pass ammonia-laden air over six stacked trays holding fine (1.17 to 2.36 mm) and coarse (2.36 to 4.70 mm) zeolite beads. The device removed 15 to 45 percent of ammonia in a contact time of 1 second (Ullman, 2004).
A study by Kithome et al. (1999) also found that zeolite is effective at reducing ammonia vapors. The researchers added natural zeolite (38 percent weight) to poultry droppings and yielded a 44 percent reduction in ammonia loss. As an added benefit, the droppings treated by zeolite contained higher nitrogen levels, as it was not released from the waste in the form of ammonia (Ullman, 2004).
Karamanlis et al. (2008) fed a group of 5,200 broiler chickens a basil diet supplemented with zeolite and also mixed zeolite with sawdust used as bedding material. The objective of the study was to examine the effect of clinoptilolite on the performance of broilers and on the quality of their litter.
Results indicated that chickens on the zeolite diet and bedding grew at a faster rate (p<0.05) and scientists noted a decrease in the level of organic content in litter samples. Overall, the mean ammonia concentration in litter was significantly lower when compared to other groups of broilers.
Researchers concluded that the incorporation of clinoptilolite zeolite in feed and bedding had a positive effect on growth and the quality of litter (Karamanlis et al., 2008).