air quality

Ammonia (NH₃)

Produced from manure; causes odor, air quality issues, and animal/human health concerns

Dust (PM)

Particulate matter (TSP, PM10, PM2.5); comes from animals, feed, litter, and manure

Odors

Complex mix of gases from manure, litter, and microbial activity

Greenhouse gases

CO₂, CH₄, N₂O; produced from respiration, manure, and microbial processes

Primary emission sources

Animal buildings, manure storage, and land application

Occupational air issues

Dust, NH₃, and H₂S exposure inside barns and pits

Local air issues

Odor, dust, flies, chemical drift affecting neighbors

Regional air issues

PM10, PM2.5, NH₃ deposition, VOCs/ozone

Global air issues

Greenhouse gases (CO₂, CH₄, N₂O)

Why ammonia matters

Irritates eyes/lungs, reduces animal performance, contributes to PM formation

NH₃ generation

Produced when urea/uric acid in manure breaks down

NH₃ control priority

Reduce generation first; then capture or disperse

Effect of bedding on NH₃

New bedding reduces NH₃ emissions compared to built‑up litter

Dietary protein effect

Higher crude protein increases NH₃ emissions

What increases dust

Dry manure, animal activity, feed, litter disturbance

Dust health effects

Respiratory irritation, pathogen transport, reduced air quality

Outdoor dust drivers

Loose manure depth, animal activity, manure moisture

Odor sources

Manure, litter, anaerobic decomposition, dust carrying odor compounds

Odor control approach

Prevent generation → capture/destroy → disperse

Main livestock GHGs

CO₂, CH₄, N₂O

GHG sources

Respiration, manure storage, microbial fermentation

Poultry GHG contribution

Poultry = 0.07% of U.S. GHG emissions

Cleanliness

Frequent manure removal reduces NH₃, odor, and dust

Proper bedding

Absorbs moisture; reduces microbial activity and NH₃ release

Dietary manipulation

Lower crude protein reduces NH₃; results vary

Acidifiers

Lower pH → convert NH₃ to NH₄⁺ → reduce emissions

Common acidifiers

Alum, ferric sulfate (Klasp), PLT (sodium bisulfate)

Zeolite

Adsorbs NH₄⁺; reduces NH₃ release

Bedding treatment benefits

Lower NH₃, better welfare, reduced pathogens

Vegetative environmental buffers (VEBs)

Trees/grasses reduce dust and NH₃ by 21–74%

Biofilters

Filter exhaust air; reduce odor, NH₃, and dust

Scrubbers

Capture NH₃ and dust; effective but costl

Oil sprays

Reduce dust and odor; inexpensive

Water sprays

Control dust in outdoor lots

NH₃ measurement

Chemical tubes, electronic sensors, or analytical instruments

Dust measurement

Filters (gravimetric) or laser sensors (real‑time)

Odor measurement

GC‑MS‑O or human olfactory panels