Animal Confinement

Livestock confinement buildings, which house mass-production operations and are semiautomated, have replaced outdoor, low-volume livestock production over the past two decades.

1. Infectious agents, dusts, and gases concentrate in livestock confinement buildings.

a. Swine confinement buildings appear to be the worst in terms of the number at risk and the frequency and severity of health problems that result. Swing confinement workers' health problems have also been more completely studied.

b. Dusts in swine confinement houses contain feed grain dust, dried feces, bits of hair, animal dander, pollen, insect parts, bacteria and endotoxins, and fungal spores.

c. Dusts are heavier when animals are handled or moved and in winter when confinement buildings are closed to keep in heat.

d. Irritant, toxic, and asphyxiant gases may build up to unhealthy levels in confinement buildings because of breakdown of animal wastes on floors and in manure pits. those present in highest concentrations and most commonly include hydrogen sulfide, methane, ammonia, and carbon monoxide and dioxide.

2. Health effects.

a. Short-term health effects include nonspecific airway hyperactivity and bronchitis with productive cough, chest tightness, and wheezing.

b. A flu-like illness with fever, myalgia, cough, chest tightness, and headache may occur after four to six hours delay after working in a confinement building in especially dusty procedures like moving, handling, and sorting animals.

c. Long-term health effects include symptoms typical of airway obstruction and chronic bronchitis.

d. Hydrogen sulfide causes irritation (especially of the eyes) and cellular asphyxiation. If hydrogen sulfide exposure is sufficiently high, sudden death may occur.

e. Ammonia exposures may result in upper airway irritation, adult respiratory distress syndrome (ARDS,) bronchiolitis obliterans, and chronic bronchiectasis as well as alkali skin burns and eye injuries.

3. Prevention and reduction of exposures.

a. Engineering and management controls ensure that ventilation, cleaning of the buildings, and other measures to reduce the buildup of hazardous substances are adequate.

b. Personal protective equipment may be used to reduce exposures but is not as effective as engineering and management controls.