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Conference paper, 2005

Ammonia release in floor housing systems for laying hens

Gustafsson, Gösta; von, Wachenfelt Eva


Ammonia Release in Floor Housing Systems for Laying Hens G. Gustafsson and E. von Wachenfelt Swedish Univ. Agric. Sciences, Dept. of Agr. Bios. and Technology, 230 53 Alnarp, Sweden., eva ABSTRACT Investigations about how different factors affect concentration and release of ammonia have been carried out at JBT:s research station Alnarp Södergård. A climate chamber was equipped with a floor housing system for laying hens which also was supplied with a manure system with conveyors below a draining floor. How age, storage time of manure, ventilation rate, ventilation technique, bedding materials, concentration and release of ammonia was investigated during two production batches. The age of the hens had no influence on the release of ammonia. However, the age had an effect on the amount of manure stored in the building which influenced the release of ammonia. The investigations clearly showed that long time storage of manure will cause a rapid increase in ammonia concentrations. After about 7 days storage of manure in a bin the ammonia concentration exceeded the hygienic threshold limit value of 25 ppm. The release of ammonia from the bedding was considerably lower than from manure stored in a bin below a draining floor. The major reason why the release increased more rapidly from manure stored in a bin is probably that the major part of the manure is left on the elevated slatted floor. It was possible to keep the ammonia concentration below the hygienic threshold limit value when manure was removed daily in a bin. Housing systems with elevated slatted floors should therefore be equipped with manure systems that enable daily removal of manure. Ammonia concentration decreased when ventilation rate increased. However, the decrease did not correspond to the increase in ventilation rate. The reason is that a high ventilation rate creates a high driving force for the evaporation of ammonia from the manure. Ammonia release was also investigated when using six different bedding materials, namely; gravel, clay pellets, peat, wood shavings, shopped straw and shopped paper . The ammonia release between the materials differed a factor two. The lowest release occurred wit shopped paper and peat as bedding materials. However, using peat resulted in dirty eggs and a poor classification of the eggs. The highest release occurred with gravel as bedding material. Keywords: Manure, laying hens, ammonia, emissions, climate

Published in

Publisher: Nordiska Jordbruksforskares förening


Manure - an agronomic and environmental challenge

Authors' information

Von Wachenfelt, Eva
Swedish University of Agricultural Sciences, Department of Agricultural Biosystems and Technology

UKÄ Subject classification

Veterinary Science
Animal and Dairy Science

URI (permanent link to this page)