Swine Ventilation Design Based on Heat Production Simulation

摘要

Growing and finishing swine weight gain can be highly affected by heat stress, that often occurs in the tropical countries. Ventilation rate is an important factor to reduce the thermal load within swine housing, and it can be provided by either natural or mechanical means, or the association of both ways. The upper critical temperature for growing-finishing swine is influenced by the ventilation rate, the presence of cooling devices and the temperature of drinking water. The swine benefits from the convection effect, by increasing its upper critical temperature, within the thermoneutral zone, in nearly 2 deg C, at an air flow of 0,5 m~3 /s. The objective of this research was to verify the change in the swine heat production, as well as the totalheat balance within the building, by simulating the number of fans and it's convection efficiency, as well as its response as a cooling alternative management to reduce the heat load. The research was carried on a production farm, in Southeastern of Brazil, and the data were collected from July to September of 1995. Four hundred swine were used in the trial kept in the experiment from 80 to 100 kg of liveweight. The heat load production were compared and showed the benefit in the housing thermal confort