Maria Luísa Appendino Nunes

Caracterização bioclimática de sistemas ao ar livre e confinado para a criação de matrizes suínas gestantes

O confinamento de matrizes suinas foi criado com o intuito de maximizar a produtividade; entretanto, existem problemas relacionados ao bem-estar animal. Objetivou-se avaliar a criacao de matrizes suinas gestantes no sistema de confinamento e ao ar livre, com relacao ao ambiente termico e as respostas fisiologicas. O experimento foi realizado em Monte Mor/SP. A avaliacao fisiologica foi realizada por meio do registro das variaveis: frequencia respiratoria e temperatura de pele. Foram registradas as variaveis meteorologicas: temperatura de bulbo seco, temperatura de bulbo umido e temperatura de globo negro, caracterizando o ambiente por meio da entalpia e indice de temperatura de globo e umidade. Foram utilizados seis animais por tratamento. O delineamento experimental foi inteiramente casualizado em parcelas subdivididas, e as medias comparadas pelo teste de Tukey. As variaveis fisiologicas e meteorologicas apresentaram valores superiores no confinamento. O sistema de criacao ao ar livre potencializou as trocas termicas entre os animais e o ambiente, o que refletiu em menor estresse por calor observado nos animais.

Physiological evaluation of heat stress in gestating sows under different housing systems in bedding and concrete floor

The purpose of this paper was to observe the use of bedding (wood shavings) in physiological variables that indicate thermal stress in gestating sows. The experiment was conducted in order to evaluate the effect of two types of floor (concrete and wood shavings). Worse microclimatic conditions were observed in bedding systems (P 0.05) but the skin surface temperature was higher in the bedding systems. The same occurred with the respiratory rates. The physical characteristics of the floor material influenced the rate of heat loss by conductance. Estimated values were 35.04 and 7.99 W m-2 for the conductive heat loss between the animal and floor for treatments with or without bedding, respectively. The use of bedding in sow rearing has a negative impact on microclimatic conditions, what implies in thermoregulatory damages.

Evaluation of the thermal efficiency of materials used as roofing systems in poultry houses.

The objective was to evaluate the reduction of radiant thermal load (RTL) and in characteristics related to thermal comfort provided by different combinations of tiles and commercial linings, through reduced and distorted scale models. This aimed to evaluate the efficiency of lining as an element to attenuate solar radiation two types of tiles (ceramic and fibrous cement) were studied associated with three different liners (linings A and B and thermal reflective C). The liners A and B, were installed under the inside part of the roof in the scale models and the thermal reflective blanket C was placed over the installation in order to simulate the thermal comfort provided by the roof shading. Meteorological variables were recorded, to the subsequent calculation of thermal comfort environmental indexes (enthalpy, black globe temperature and humidity index GTHI and radiant thermal load). Variations on the surface temperature of tiles and liners were also recorded to identify the spatial variation of temperature at different times of the day. The results showed a statistical difference between the materials used for roofing and lining. Liner B presented the highest reductions of RTL and GTHI values. The thermal mapping of the surface temperature of tiles showed that the lowest temperature were found in fibrous cement roofs white painted, while the highest surface temperatures were found in the unpainted ceramic tiles. The use of roof shading in reduced and distorted scale models did not improve the thermal conditions of the evaluated environment.

Bioclimatic Evaluation of Gestating Sows housed in Bedding and Concrete Floor Systems

Abstract: Regarding to heat stress at animal facilities, the use of bedding and pig production might be meaning of trouble, besides that, there is few literature talking about this type of system during the gestation. The objective of this work was to verify the effect of using shallow wood shavings bedding to improve the thermal comfort in gestating sows when they are housed at different systems during the gestation period. 1) full-period group housing + shallow wood shavings bedding; 2) full-period group housing + concrete floor (no bedding); 3) group housing after 28 days of gestation in the cage + shallow wood shavings bedding and 4) group housing after 28 days of gestation in the cage + concrete floor (no bedding). Rectal temperature (RT) and superficial temperature (ST) responses of gestating sows were taken during 8 periods at 3 days by 3 different hours per day. Environmental variables were taken using the same methodology. Bedding utilization has increased mean air temperature and enthalpy inside the facilities. Means of enthalpy showed values of 55.25kJ/kgdry air (shallow wood shavings bedding) and 52.88kJ/ kgdry air (concrete floor). However, rectal temperature has not changed doing the bedding system. On the other hand, the superficial temperature on the head showed higher when bedding treatment was applied compared back to concrete floor (34.47C and 33.947C, respectively). The superficial temperature of the shoulder, loin and ham have showed statistical significance (P<0.05) between bedding effect and housing systems, then, bedding showed higher values. The range of temperature for thermal comfort was changed since bedding was used. It was possible to conclude that for using bedding during summer time there is some disadvantages during gestation period for sows. However, this system should be analyzed in general, emphasizing alternative ways to minimize loss by heat stress at tropical conditions.