BIOCLIMATIC LIVESTOCK ZONING OF MARANHÃO STATE, BRAZIL

Abstract

The production environment in which animals are kept can be classified by bioclimatic indexes expressing the conditions of thermal comfort to different species. In the state of Maranhão (MA), located in Northeast Brazil region, stand out in the livestock sector the beef cattle, pig and poultry production. In order to check the conditions of thermal comfort in the state for these species was held a bioclimatic zoning, taking into account the temperature and humidity index (THI) and Black Globe Temperature and Humidity Index (BGTHI). Estimates of the indexes were performed from meteorological data obtained from the database of the National Institute of Meteorology (INMET). Seven county were considered, and were chosen taking into account the greater amount of information available over the years. The variables analyzed were: air temperature, relative humidity and atmospheric pressure. Bioclimatic indexes were determined by using mathematical equations applied in Microsoft Excel®. Using the Surfer 8.0® program, were generated maps with bioclimatic zones to the state. Taking into consideration the comfort levels recommended as safe for poultry, pigs and cattle in all stages of production (THI 70-74 and BGTHI 72-75), the analyzed bioclimatic zones showed no conditions for comfort and optimal performance of these species, considering that the THI ranged from 74.1 to 75.8. and BGTHI from 80.0 to 82.3. Can be concluded that in the cities checked, the production systems of these species need investment in measures to promote the correction of microclimate to establish optimal levels of animals thermal comfort.