ABSTRACT
Um condicionador de ar para biotérios foi montado com módulos termoelétricos de efeito Peltier. Para troca térmica foram empregados dissipadores externos a água, obtendo-se Δt de 21 ºC, rendimento de 46,02%, consumo de 524 W/h. A simulação matemática de operação, com mistura de ar não condicionado, mostrou que o sistema pode servir a aproximadamente 137 microisoladores padrão rato com dissipação externa a água. O sistema termoelétrico mostrou ainda, precisão de ± 0,1 ºC, nas temperaturas experimentais, o que é impossível num sistema de freon. Foram ensaiadas as seguintes temperaturas: 22º, 24º, 26º, 28º e 30 ºC, obtendo sempre estabilidade e precisão, independentemente da temperatura ambiental onde o equipamento estava em operação.
An air conditioner for animal facilities was mounted with thermoelectric modules of Peltier effect. For heat exchange, a water dissipation system was employed.The air temperature difference (Δt) was 21 ºC, the performance was 46.02% and the power consumption was 524 W/h. The mathematical simulation of operation, with mixture of no conditioned air showed that the system can serve approximately 137 standard mouse microisolators, with water dissipation system. The thermoelectric system also showed an accuracy of ± 0.1 ºC at the experimental temperatures, which is impossible in a system of Freon Gas. We tested the following temperatures: 22º, 24º, 26º, 28º and 30 ºC, always getting stability and accuracy at any outside temperature.
Subject(s)
Animals , Air Conditioning , Temperature , Animals, LaboratoryABSTRACT
Ratos wistar foram mantidos individualmente, em gaiolas metabólicas de arame, sem abrigo, em sistema microambiental, sob fluxo direto de ar a 0,6 m/s, nas temperaturas de 22°, 24º, 26º, 28º e 30º C. O consumo de ração e o ganho de peso foram comparados do final de 5 dias (ANOVA; Tukey-Kramer). No total, sete grupos de 10 animais cada foram comparados. Para a faixa de 22ºC foram utilizados três grupos, sendo um grupo experimental e dois grupos controles.Um deles foi mantido em condições ambientais semelhantes a biotérios convencionais sob ventilação geral diluidora (VGD) C1.O outro grupo controle (C2) foi mantido no interior do equipamento de ventilação microambiental, porém, sem o direcionamento de ar, simulando a VGD. Os resultados obtidos demonstram claramente que animais mantidos sob ventilação microambiental direta a 26º, 28ºe 30ºC apresentam o mesmo ganho de massa corpórea que animais do grupo C1. Os grupos de animais mantidos a 22º e 24ºC, apresentaram menor ganho de massa corpórea quando comparados a C1 (p<0,001 e p<0,01 respectivamente). O ganho de peso de todos os grupos experimentais, quando comparado ao C2, apresenta diferenças estatísticas, exceto o mantido a 30°C que apresentou índice de ganho de peso equivalente a C2. O consumo de ração de todos os grupos se manteve constante. Somente o grupo E5 apresentou uma redução no consumo de ração quando comparado aos grupos C1 eC2 (p<0,05 para as duas comparações).
Wistar rats had been kept individually, in metabolic wire cages, without shelter, in microenvironmental system, under direct air flow at 0,6m/s, under temperatures of 22°, 24º, 26º, 28º and 30º C. The food consumption and the weight gain had been compared in the end of 5 days (ANOVA; Tukey-Kramer). In the total, 7 groups, 10 animal seach, had been compared. For the 22ºC temperature, had been used 3 groups, one experimental and two controls. One of them was keptin similar ambient of conventional laboratory animal rooms conditions (general diluitory ventilation, GDV) - C1. The other control group (C2) was kept in the interior of the equipment of microenvironmental ventilation, however, without the direct air flow,simulating the GDV. The gotten results demonstrate clearly that animal kept under direct microenvironmental ventilation at 26º, 28º and 30º Chave the same gain of corporal mass that C1 group. The groups keptat 22º and 24ºC, had less corporal mass gain when compared to C1(p<0,001 and p<0,01 respectively). The weight gain for all the experimental groups, when compared to C2, presents statistical differences, except 30°C group, that was equal to C2. The food consumption of all the groups was constant. Only the 30°C group presented a reduction in the food consumption when compared with the groups C1 and C2 (p<0,05 for the two comparisons).
Subject(s)
Animals , Animals, Laboratory , Air Pollution, Indoor/adverse effects , Rats , Animal Feed/adverse effects , Temperature , Ventilation/methods , Weight GainABSTRACT
Previous studies reported that rats (Rattus norvegicus) kept under microenvironmental ventilation systems (MEV) present better productive and health parameters when compared to animals kept under general diluting ventilation (GDV). The objective of the present research trial was to evaluate hematological and biochemical profiles of rats kept under MVS. In order to achieve this objective, two different trials were designed: Trail 1 (E1), in which it was evaluated the reproductive performance of males and females submitted to two different air speed limits - FV1, from 0.03 to 0.26 m / sec and FV2, from 0.27 to 0.80 m / sec. In Trial 2 (E2) it was evaluated different bed change intervals (3, 5, 7 and 9 days), for males kept under constant air speed (0.5 m / sec). Values for hemogram and biochemical patterns of these animals were compared to those of rats kept under GDV. Results show statistical differences in some of the studied parameters not only for the comparison between GVD and E1 and GVD and E2, but also between both groups submitted to MEV (E1 and E2). However, values found for all studied parameters are inside the normal range reported for this species, what indicates that MEV does not induce important changes in the physiological parameters evaluated