Temperature & Humidity Requirements for Mulberry Silkworm Rearing

The natural temperature and humidity that are not suitable for sericulture production are adjusted manually to reach the temperature and humidity suitable for sericulture production. Under natural conditions, due to the influence of high temperature and humidity, as well as the influence of the continuous activities of people and silkworms themselves, the temperature and humidity around the silkworms fluctuate and must be adjusted. Airflow also plays a role in regulating temperature and humidity, which is an available natural condition.

Feeding temperature requirements

Silkworms are temperature-changing animals, and their body temperature changes with changes in temperature. Generally, the body temperature of the small silkworm is slightly lower than the temperature, and the body temperature of the large silkworm is slightly higher than the temperature. Looking at the influence of temperature from the growth and development of silkworms: at 7.5℃, only mulberry can be eaten; above 10℃, the higher the temperature, the faster the development, but if the temperature is above 30℃ for a long time, it will be difficult to develop, especially when the silkworm is large. Decrease; when the temperature reaches 37℃, the silkworms are in a state of depression, or are inactive and die; when the temperature is above 40℃, they can only live for a short time. In the low temperature below 15℃, the body of the silkworm becomes cold, the movement is inactive, the development is slow, the weight is light, the body is small, and the cocoon formation is small; when the temperature is below 7.5℃, it does not eat and stops developing. Temperature also has an effect on cocoon quality and silk quality. Generally, the small silkworm stage has a small influence, while the large silkworm stage has a large influence. The most significant effect of temperature on silkworm rearing is the passage of instar and the strength of the silkworm. The feeding temperature is within the range of 15～35℃, and the whole instar period is 68.22 days for those raised at 15℃; for those raised at 30℃, it is shortened to 18.15 days; for those raised at 35℃, the instar is 18.23 days. It shows that the effect of temperature on shortening the instar is limited. In terms of the robustness of silkworms, the life rate of silkworms raised at 15°C and 35°C is very low, especially for the 5th instar if raised at 35°C, almost all of them died. But feeding at 20°C, 25°C, and 30°C, compared with 15°C and 35°C feeding, its life rate is greatly improved. The comprehensive results of many experiments proved that the temperature’s influence on the life rate of silkworms is best in the range of 20-30°C. However, each instar has the most suitable breeding temperature for each instar. The breeding temperature of silkworms should be suitable for the healthy growth of silkworms, strong vitality, high-quality cocoons, high cocoon production, good silk quality, and a relatively short and short development process. Together again.

Feeding humidity requirements

Humidity has an important impact on the growth and development of silkworms and the speed of water distribution in mulberry leaves. Silkworms mainly rely on the water in mulberry leaves to obtain external water. Part of the water loss is excreted in the form of silkworm urine and silkworm feces, and the other part is emitted from the surface of the silkworm body through the air valve and the skin in a gaseous form. However, whether the water is easy to disperse or not is restricted by the humidity in the air. In addition, the water divergence, due to the large difference in instar of silkworms, is usually easier for small silkworms to diverge in water, but difficult for large silkworms. The water divergence of the 3rd instar silkworm is more than twice that of the 5th instar silkworm. Humidity also affects the length of the silkworm’s instar, that is, the higher the humidity, the shortening of the silkworm. Humidity affects the vitality of the silkworm. Because the size of the silkworm instar is very different, usually the small silkworm stage has a strong vitality at 90% humidity, and the large silkworm stage. Strong vitality at 75%. The proper humidity for sericulture is that the silkworms can fully feed on the mulberry leaves without hindering the divergence of water from the silkworm body, so that the silkworms grow strong and form excellent cocoons. Humidity suitable for each instar: 85-90% for the first instar, 80-85% for the second instar, 75-80% for the third instar, 70-75% for the fourth instar, 65-70% for the fifth instar.