The effect of microwave radiation on the primary IgM response to sheep red blood cells in mice.

We investigated the changes in the number of plaque-forming cells (PFC) in spleens of CBA mice after microwave (MW) irradiation. The mice were immunized with sheep red blood cells, the number of PFC was determined on days 4 and 5 after immunization. Mice received single doses of MW irradiation on days 1, 2, or 3 after immunization (exposure duration 1 to 9 min). It was found that the number of PFC was changed after MW irradiation and that this effect depended on the absorbed dose. Shorter exposures for 1, 3, and 5 min (SA = 4, 12, and 20.1 kJ/kg) stimulated the formation of PFC, exposures for 7 and 9 min did not change the number of PFC. After MW heating (exposure 5 min), the rectal temperature of mice was elevated by 2.5 degrees C. If the same thermal effect was induced by elevating the environmental temperature, the number of PFC was not increased. The observed changes in PFC number are probably due to the specific effect of MW radiation.

[An electric dynamic katathermometer and the thermal environment in pig farrowing pens]. / Elektrický dynamický katatermometr a tepelné prostredí v porodnách prasat.

Temperature conditions were measured with an electric dynamic catathermometer (EDC) and thermometers in pig farrowing houses 13 and 90 cm above the floor of the central and side corridors, boxes for sows and in piglet pens, heated with electric infra-radiators (input 525 W). The heat flow density of the EDC sensor, characterizing the cooling properties of the environment, was higher near the floor, at the ends of stables, on the sides exposed to wind, and after turning on the fan. The thermal conditions in the farrowing houses were therefore highly variable. In the piglet pens the heat flow density was usually kept at a very low level, owing to the thermal radiation of the electric infra-radiators, with possible bad implications for production. However, these facts cannot be documented just by the current measurements of air temperature.

[An electricodynamic cathethermometer and heat conditions in pens for piglets]. / Elektrický dynamický katatermometr a tepelné podmínky v doupatech pro selata.

In the farrowing houses the electric dynamic katathermometer (EDK) was used to determine the thermal conditions in boxes for piglets heated by electric infraradiators (EIZ) with an input of 525 W. The density of heat flow of the EDK sensor in the boxes which characterizes the cooling properties of this environment was zero or only very low if the infraradiators were installed 60 to 70 cm above the floor of the boxes, i. e. so as to temper the air to a temperature recommended by the standard. This is apparently caused by the relatively great radiation from the infraradiator which is not registered by the mercury thermometer but is absorbed by the body surface of the piglets and may lead to their overheating. A desirable increase in the cooling properties of the box environment and of the other spaces of the farrowing house was achieved by decreasing the infraradiator input to 260 W and suspending them 50 cm above the floor of the boxes. Their fixation at a greater height allowed the further effective regulation of the heat conditions in the boxes while at the same time cutting down electric energy consumption by a half.