To Provide a Double Feeder in Growing Pigs Housed under High Environmental Temperatures Reduces Social Interactions but Does Not Improve Weight Gains

SIMPLE SUMMARY: Competition for food can increase if pigs concentrate feeding times in the cool hours of the day during the warmest seasons. The present study addresses whether providing the animals with a double feeder would benefit the performance of pigs when subjected to high environmental temperatures. The results showed that high environmental temperatures reduced the final body weight of pigs and increased the percentage of fat in the carcass of the animals. When provided with two feeders instead of one, the animals reduced the number of social interactions, so less competition for food was achieved. However, an unexpected result was a decrease in the body weight of the animals with two feeders when compared to the animals with one, so in terms of performance, the strategy failed in providing the expected results. ABSTRACT: Heat stress and competition for food are two major challenges in pigs reared in intensive conditions. The aim of the present work was to study the effect of providing a double feeder for pigs reared under two different environmental temperatures. In addition, two types of flooring, of 100% slat and 30% slat 70% concrete, were also considered. A total of 256 pigs in the growing-finishing period (from 27 kg to 110 kg) were housed using two environmental temperatures: control (from 18 °C to 25 °C) and heat stress (above 30 °C six hours a day). They were housed in 32 pens of 8 pigs each, distributed into 4 rooms (16 with one feeder and 16 with two). Pigs subjected to temperatures above 30 °C up to six hours had lower body weight gains than pigs subjected to a maximum temperature of 25 °C, confirming that thermal stress negatively affects performance in pigs. In addition, heat stress affected the final product by decreasing the lean percentage of carcasses by 2.6%. A double feeder reduced the presence of negative social behavior, especially in the feeding area, but body weight was lower than when one single feeder was used. A 30% slat 70% concrete floor showed better results in the pig stress indicators and body weights than 100% slat. It is concluded that providing a double feeder in the pens, although reducing the presence of negative social interactions, negatively affected body weight, in comparison to pigs fed with just one feeder.