Abstract:
A total of 236 lagoon and 35 hoop barn manure samples were collected during 2000
from Kansas swine operations to determine
the effects of production phase and season of
the year on their nutrient concentration.
Lagoon analyses revealed that nitrogen
concentrations were lower during the summer
and fall seasons compared to winter and
early spring. In addition, levels of nitrogen
were highest in nursery, wean to finish, and
finishing lagoons compared with sow and
farrow-to-finish lagoons. Phosphorus levels
for all lagoons increased from February until
June, but then declined steadily throughout
the remainder of the year. The concentration
of phosphorus also was highest for wean-tofinish and finishing lagoons and the lowest
for farrow-to-finish lagoons. No seasonal changes in nitrogen and phosphorus concentrations were observed in manure from hoop barns. Therefore, season and type of production phase affects the nutrient content of Kansas swine lagoons, and producers will benefit from obtaining individual analyses from their lagoons when developing nutrient management plans rather than utilizing published reference values.