2013 Annual Report
The second component will be conducted in a production system to determine MP by both the pigs and the housing systems. Two swine houses located at the USMARC will be used for these studies. Air temperature, RH, and CO2 concentration of both inside and outside will be recorded at 15-min intervals for a 24 hour period at least one time a week for the duration of the production cycle. Prior to initiation of the experiment each of the exhaust ventilation fans will be calibrated in-situ at various static pressures to develop the actual fan performance curves. Operational status of each exhaust fan will be monitored continuously. THP and MP data will be fitted to regression models each for barrows and gilts with main effects of temperature and body weight, using appropriate interaction, linear, and quadratic terms.
The grant was written to support four calorimeter laboratory studies, with the objective of collecting total heat production (THP) from both barrows and gilts ranging in size from nursery age pigs through slaughter weight. The grant supported a series of field measurements, which included a range of ages from farrowing, nursery, finishing, and gestating. The objective of the field measurement was to collect field scale moisture production and verify our THP collected during the calorimeter laboratory studies.
The laboratory studies and field measurements have been concluded, the data have been summarized and a final report and a publication have been submitted. Overall, HP was found to be 16% higher than current standards. In order to predict moisture production (MP) from the entire facility rather than just the animals, the waste handling systems, sprinkle cooling systems, and non-vented gas-fired heaters were monitored and found to contribute significantly to the overall MP. Continuous measurements showed a diurnal HP pattern that was higher during light than dark periods, with peaks just after lights came on and just before lights went off. With this data, equations to predict HMP from the pigs have been generated. In addition, prediction of the building’s contributing moisture has been estimated at 51g hr-1 m-2. With these updated HP and MP equations and the estimation of the building component of moisture production, the standards for heat and moisture production can be updated. Updated standards will ensure new swine facilities have properly sized fans and heater systems which contribute to adequate climate control and increase building life. The remaining objective on this grant is presentation of the results, which is scheduled for January, 2014.