Análise do conforto térmico para frangos de corte no RS em cenários de mudança climática

Abstract

Studies that evaluate the possible impacts of climate change on animal production are important for planning and defining production strategies that ensure food sovereignty and safety. Therefore, the objective of this work is to analyze the thermal comfort for broilers in Rio Grande do Sul in climate change scenarios in seven municipalities of the state, considered the largest producers of chicken. The temperature values used in the research were obtained from the INMET weather station database for the period 2000 to 2020. Average, maximum and minimum monthly values were analyzed for each municipality, denominated as current values. From these, climate change scenarios were created with temperature increases as follows: +1.5ºC (scenario 1); + 3ºC (scenario 2); + 5ºC (scenario 3). Subsequently, the temperature values obtained were compared with the thermal comfort values for broilers from the first to the sixth week of life, available in the literature. Under current conditions, cold stress can occur in all months of the year and for all weeks of life of the animals, and there is no change in this condition with climate change scenarios, even the most severe ones. Heat stress is prevalent for animals from the fourth week of life onwards and is accentuated in climate change scenarios, especially in the summer months. The thermal comfort that currently occurs in the afternoon in some months of the year for animals from the first to the fourth week of life will suffer a reduction in the period of 26%, 41% and 61%, respectively, for scenarios 1, 2 and 3, if climate change is confirmed. In order to maintain ideal thermal conditions for the animals, thermal conditioning practices are necessary, both to increase and reduce the temperature inside the aviary. The incrementof heat stress in scenarios of climate change may require a greater amount of equipment than is used today, and more than one strategy may be implemented for the mitigation of heat, which will possibly impact a higher cost of production.