Seven goats were used to study the effects of heat exposure (33°C, relative humidity 70%) for 4 days on the disappearance rate of injected acetate. Significant changes in several physiological responses were observed during heat exposure. Intravenous inj ection of acetate (1.25 mmole kg^-1 of body weight) caused a marked increase in the peripheral acetate concentration at both 20°C and 33°C. At 20°C, plasma glucose increased and plasma free fatty acids decreased immediately after injection. On the 4th day of heat exposure, plasma glucose changed in a similar manner to that at 20°C, but plasma free fatty acids changed little. The fractional disappearance rate of blood acetate after injection was similar in the two environments. These results suggest that the potency of acetate utilization does not change during heat exposure.

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As materials, bivoltine silkworm races were used. The eggs were incubated continuosly at 20°C in the dark and the larvae were reared on artificial diets. Effects of photoperiod and content of soybean meal or mulberry-leaf powder in the diet on growth and development of the silkworm were investigated. Especially, diapause of the embryos in the next generation was examined. As the light source, fluorescent lamp with the wavelength above 450 nm was used, and the illumination energy adjusted to 0.32±0.01W/m²/sec.
The growth of the silkworm was influenced to a large extent by photoperiodic conditions, and the effect had the turning point at LD6: 18; namely, when the larvae were reared under LD6: 18, the shortest duration of larval period and the lightest weights of cocoon and cocoon shell were obtained. In this photoperiodic condition, both survival and diapause ratios were the highest among those in other conditions. It was assumed that this reaction might be ascribed to the direct effect of light to the larvae, not due to the deterioration effect of the diets by the light.
When the content of soybean meal was varied in the diets, distinct differences in diapause were detected only under the photoperiodic conditions, LD6: 18 and D24. Namely, the non-diapause egg rate was increased with increasing amount of soybean meal in the diets. In this case, the weight of cocoon and cocoon shell also increased as a result of the addition. However, the relationship between the appearance of diapause and the content of the mulberry leaf powder in the diet was not recognized.

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