ABSTRACT The objective of this study was to characterize the thermal environment and evaluate the behavior of finishing pigs housed in deep bedding and conventional systems. The work was carried out in the Department of Animal Science of the Federal Institute of Education, Science and Technology of Southeast Minas Gerais, Rio Pomba campus. Three pens were used in an installation for breeding pigs in their finishing phase. Two pens contained deep bedding, with wood shavings and rice husks. The remaining pen was a conventional system. The behavior of the piglets was observed from 8 a.m. to 5:30 p.m., noting the behaviors with the use of an ethogram, while data relating to the thermal environment in the stalls were automatically collected using data loggers. Thermal environment data for all systems presented thermal stress conditions. Regarding behavioral variables, animals in conventional systems had a higher frequency of visits to feeders, while animals in the deep bedding system were more active and visited the drinking fountains more frequently. Despite the higher level of activity of the animals in the deep bedding system, it is not possible to confirm that the deep bedding provides a better degree of well-being for the animals under thermal stress conditions.

ABSTRACT Although dry bulb temperature (T) is the environmental variable most commonly used to classify thermal comfort in pigs, environmental assessment ratios provide more accurate information. The objective of this study was to correlate the sound pressure levels (SPL) produced by piglet vocalization with the thermal environment observed during the nursery phase, and subsequently establish thermoneutrality ranges. The experiment was conducted on a pig farm where T, relative humidity (RH), and SPL data were recorded between 9 am-5 pm for 42 days. The association between SPL and T in nursery phase piglets was verified; for thermal comfort to be possible, SPLs were 56.3 to 60.3 dB. The SPLs were subsequently used in predictor equations of ratios, and thermal comfort ranges were 74.4-78.3 for temperature and humidity ratio (THI), and 71.6-75.8 for globe temperature and humidity ratio (BGHI). Although the SPL proved to be a convenient indicator of thermal comfort for the evaluation of pigs, further studies developed in different phases of the production system are required.

RESUMO O objetivo do trabalho foi avaliar a concentração de gases em três instalações de crescimento e terminação para suínos, com tipologias construtivas diferentes no que tange ao piso e divisórias. Compararam-se três tratamentos: baia com lâmina d’água, baia com piso parcialmente vazado nas laterais e baia com piso parcialmente vazado nas laterais e no centro. Foram feitas medições das concentrações instantâneas de amônia (NH3, ppm) e dióxido de carbono (CO2, ppm) a nível dos animais; também foram registrados os níveis de pressão sonora (dB) a nível dos animais e a 1,50 do piso. Observou-se que a baia com lâmina d’água foi a que apresentou o maior valor médio de concentração de NH3. Apesar de haver ocorrido diferenças significativas nas concentrações de CO2, os valores encontrados estão dentro dos limites permitidos pelas normas brasileiras, presumindo-se, assim, que as instalações não ocasionam desconforto em relação aos níveis de CO2. A baia com lâmina d’água demostrou proporcionar um possível desconforto aos animais, com nível de concentração de NH3 acima de valores que já podem acarretar problemas aos animais de acordo com o preconizado pela literatura. Não foi observada influência do tipo de piso da baia sobre a pressão sonora em nenhum horário.

ABSTRACT The objective of this study was to evaluate the concentration of gases in three swine growing and finishing facilities with different building typologies, regarding floor and dividers. The experiment compared three treatments: pen with water depth, pen with partially slotted floor on the sides, and pen with partially slotted floor on sides and in the center. Measurements of instantaneous concentrations of ammonia (NH3 ppm) and carbon dioxide (CO2 ppm) were taken at animal level. The levels of sound pressure (dB) at animal level and at 1.50 m from the floor were also recorded. It was observed that the pen with water depth was the one with the highest average concentration of NH3. Although there was a significant difference in CO2 concentrations, the observed values are within the limits allowed by the Brazilian standards; thus, it is assumed that the facilities do not cause discomfort in relation to CO2 levels. The pen with water depth possibly caused discomfort to the animals, since the NH3 concentration was above the values that can cause problems to the animals, according to the recommendation of the literature. There was no influence of the type of pen on the sound pressure at any time.

ABSTRACT This study aimed to evaluate gas levels and the acoustic environment (noise) of growing-finishing swine in different facilities, one composed of shallow pool (SP) and another of partially slatted floor (PSF). Sensors and a sound level meter were used to measure gas concentrations (CO2 and NH3) and noise at 1.50 meters above the ground and at animal height. Data on gas concentrations and noise levels were measured at 9am, 12pm, and 3 pm. Results showed differences (P<0.05) between noise levels at animal height and gas concentrations measured in relation to stall type and data collection time. The highest noise values were found in the shallow pool stall, measured at animal level. The highest NH3 (13 ppm) and CO2 (1174.5 ppm) values were observed in the shallow pool stall at 3pm. The stall floor with shallow pool seems to provide greater welfare in relation to noise level for growing-finishing swine.