Author
Miles, Dana | |
Branton, Scott | |
LOTT, B - MISS STATE UNIVERSITY | |
MILLER, W - ANIMAL OPTHAL. CLINIC |
Submitted to: International Poultry Forum Proceedings
Publication Type: Abstract Only Publication Acceptance Date: 1/20/2003 Publication Date: 1/20/2003 Citation: Miles, D.M., Branton, S.L., Lott, B.L., Miller, W.W. 2003. Broiler cornea and body weight response to low level ammonia exposure [abstract]. International Poultry Forum Proceedings 82:126. Interpretive Summary: None required. Technical Abstract: Recommended ammonia levels in broiler houses are 25 to 50 ppm, the lower of which is set by U.S. regulatory agencies, NIOSH, and OSHA, for the human 8-hour exposure limit. Ammonia concentration in a commercial house can easily exceed 150 ppm, especially during the brooding phase. Two trials were conducted where 60 male commercial broilers at 1d of age were placed in each of eight environmentally controlled chambers on 10 cm of fresh, kiln-dried pine shavings. Birds had ad libitum water and food under continuous lighting. Anhydrous ammonia was metered into six of the chambers to maintain 25, 50, and 75 ppm (2 chambers for each level). No ammonia was added to the remaining two chambers (control). At the beginning of each trial, 10 birds were randomly selected from each chamber, permanently identified and had weekly ocular examinations through the remainder of the study. The examiner did not know the chamber origin of each bird. At four weeks, ammonia addition was discontinued and birds were grown to market weights. Broilers in each chamber were weighed weekly. Birds exposed to 25 ppm ammonia demonstrated keratitis at 3 weeks of exposure similar to keratitis observed in birds exposed to 75 ppm ammonia for 1 week. Body weights were most affected by the 75 ppm level; this group was 75% of the control at 3 weeks of age, but had recovered to 91% of the control at 7 weeks. Birds exposed to low levels of ammonia demonstrate ocular disease and increasing concentrations of ammonia increase the severity of ocular disease and reduce growth rates. |